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Carbon dioxide insufflation in open-chamber cardiac surgery: A double-blind, randomized clinical trial of neurocognitive effects
Abstract
The aims of this study were first to analyze neurocognitive outcomes of patients after open-chamber cardiac surgery to determine whether carbon dioxide pericardial insufflation reduces incidence of neurocognitive decline (primary end point) as measured 6 weeks postoperatively and second to assess the utility of carbon dioxide insufflation in cardiac chamber deairing as assessed by transesophageal echocardiography.
A multicenter, prospective, double-blind, randomized, controlled trial compared neurocognitive outcomes in patients undergoing open-chamber (left-sided) cardiac surgery who were assigned carbon dioxide insufflation or placebo (control group) in addition to standardized mechanical deairing maneuvers.
One hundred twenty-five patients underwent surgery and were randomly allocated. Neurocognitive testing showed no clinically significant differences in z scores between preoperative and postoperative testing. Linear regression was used to identify factors associated with neurocognitive decline. Factors most strongly associated with neurocognitive decline were hypercholesterolemia, aortic atheroma grade, and coronary artery disease. There was significantly more intracardiac gas noted on intraoperative transesophageal echocardiography in all cardiac chambers (left atrium, left ventricle, and aorta) at all measured times (after crossclamp removal, during weaning from cardiopulmonary bypass, and at declaration of adequate deairing by the anesthetist) in the control group than in the carbon dioxide group (P < .04). Deairing time was also significantly longer in the control group (12 minutes [interquartile range, 9-18] versus 9 minutes [interquartile range, 7-14 minutes]; P = .002).
Carbon dioxide pericardial insufflation in open-chamber cardiac surgery does not affect postoperative neurocognitive decline. The most important factor is atheromatous vascular disease.
... The major concern in operation on the beating heart is the prevention of air embolism, which occurs when air presents in the left ventricle and LV pressure is greater than that in the aorta root. 14 We prevented this complication using following principles: (1) maintain high arterial line pressure, 14,15 (2) keep LA and LV to be always filled with blood, 16 sucker only sucked on a part of LA in certain stages, (3) insufflation of pericardial and pleural space by CO 2 , 15,17 and deairing by inflating the lungs right before completing the ASD closure. Mo et al 14 believed that high pressure of arterial line played important role in preventing air from the left heart going to the aorta. ...
... The major concern in operation on the beating heart is the prevention of air embolism, which occurs when air presents in the left ventricle and LV pressure is greater than that in the aorta root. 14 We prevented this complication using following principles: (1) maintain high arterial line pressure, 14,15 (2) keep LA and LV to be always filled with blood, 16 sucker only sucked on a part of LA in certain stages, (3) insufflation of pericardial and pleural space by CO 2 , 15,17 and deairing by inflating the lungs right before completing the ASD closure. Mo et al 14 believed that high pressure of arterial line played important role in preventing air from the left heart going to the aorta. ...
... In addition, the use of CO 2 in operation on the beating heart has been shown to not be associated with any neurological complications. 15 Thapmongkol et al performed ASD closure surgery for 63 patients on the beating heart. To prevent air embolism, they did not use neither CO 2 nor aortic root vent. ...
The aim of the study was to investigate the effectivity and safety of totally endoscopic cardiac surgery without robotic assistance for atrial septal defect (ASD) closure on beating hearts.
... 24 Two articles described randomized controlled trials of interventions to mitigate cognitive decline after VHD surgery. 27,29 Intraoperative infusion of gastrodin, a Chinese herb with a range of purported neuroprotective and antiinflammatory actions, reduced risk of cognitive decline 3 months after VHD surgery, 27 but in the second randomized trial, intracardiac carbon dioxide insufflation was not found to improve cognitive outcomes. 29 ...
... 27,29 Intraoperative infusion of gastrodin, a Chinese herb with a range of purported neuroprotective and antiinflammatory actions, reduced risk of cognitive decline 3 months after VHD surgery, 27 but in the second randomized trial, intracardiac carbon dioxide insufflation was not found to improve cognitive outcomes. 29 ...
... 34 The relationship between cognitive decline and comorbid medical and psychiatric conditions with VHD also deserves investigation. For instance, hyperlipidemia and coronary heart disease in individuals with VHD are predictors of postoperative cognitive decline, 29 and calcific aortic valve disease is a known cause of calcific cerebral emboli that can result in brain ischemia and stroke. Specifically, our subgroup analysis according to valve type is susceptible to confounding according to age; it remains unclear whether age may have played an even more important role in cognitive outcome than valve type. ...
OBJECTIVES:
To summarize evidence on cognitive outcomes after heart valve surgery; secondary aim, to examine whether aortic and mitral valve surgery are associated with different cognitive outcomes.
DESIGN:
Preferred Reporting Items for Systematic Reviews and Meta-Analyses systematic review and meta-analysis.
SETTING:
Cardiac surgery.
PARTICIPANTS:
Individuals undergoing heart valve surgery.
MEASUREMENTS:
We searched MEDLINE, EMBASE, and PsycINFO for peer-reviewed reports of individuals undergoing heart valve surgery who underwent pre- and postoperative cognitive assessment. Our initial search returned 1,475 articles, of which 12 were included. Postoperative cognitive results were divided into those from 1 week to 1 month (early outcomes, npooled = 450) and from 2 to 6 months (intermediate outcomes; npooled = 722). No studies with longer-term outcomes were identified.
RESULTS:
Subjects had moderate early cognitive decline from baseline (Becker mean gain effect size (ES)=-0.39 ± 0.27) that improved slightly by 2 to 6 months (ES=-0.25 ± 0.38). Individuals undergoing aortic valve surgery-who were older on average than those undergoing mitral valve surgery (68 vs 57)-had greater early cognitive decline than those undergoing mitral valve surgery (ES=-0.68 vs -0.12), but both cohorts had similar decline 2 to 6 months postoperatively (ES=-0.27 vs -0.20).
CONCLUSIONS:
Heart valve surgery is associated with cognitive decline over the 6 months after surgery, but outcomes beyond 6 months are unclear. These findings highlight the cognitive vulnerability of this population, especially older adults with aortic stenosis.
... The major concern in operation on the beating heart is the prevention of air embolism, which occurs when air presents in the left ventricle and LV pressure is greater than that in the aorta root. 14 We prevented this complication using following principles: (1) maintain high arterial line pressure, 14,15 (2) keep LA and LV to be always filled with blood, 16 sucker only sucked on a part of LA in certain stages, (3) insufflation of pericardial and pleural space by CO 2 , 15,17 and deairing by inflating the lungs right before completing the ASD closure. Mo et al 14 believed that high pressure of arterial line played important role in preventing air from the left heart going to the aorta. ...
... The major concern in operation on the beating heart is the prevention of air embolism, which occurs when air presents in the left ventricle and LV pressure is greater than that in the aorta root. 14 We prevented this complication using following principles: (1) maintain high arterial line pressure, 14,15 (2) keep LA and LV to be always filled with blood, 16 sucker only sucked on a part of LA in certain stages, (3) insufflation of pericardial and pleural space by CO 2 , 15,17 and deairing by inflating the lungs right before completing the ASD closure. Mo et al 14 believed that high pressure of arterial line played important role in preventing air from the left heart going to the aorta. ...
... In addition, the use of CO 2 in operation on the beating heart has been shown to not be associated with any neurological complications. 15 Thapmongkol et al performed ASD closure surgery for 63 patients on the beating heart. To prevent air embolism, they did not use neither CO 2 nor aortic root vent. ...
Objective:
The aim of the study was to investigate the effectivity and safety of totally endoscopic cardiac surgery without robotic assistance for atrial septal defect (ASD) closure on beating hearts.
Methods:
Twenty-five patients (adults/children: 15/10) underwent ASD closure using nonrobotically assisted totally endoscopic approach on beating heart. Three 5-mm trocars and one 12-mm trocar were used, only the superior vena cava is snared, filling the pleural and pericardial cavities with CO2, and the heart was beating during the surgery. Twenty-three patients had isolated secundum ASD (2 of which had severe tricuspid regurgitation) and two patients had ASD combined with partial anomalous pulmonary venous connection. All ASDs were closed using artificial patch, continuous suture; tricuspid regurgitations were repaired and the anomalous pulmonary veins were drained to the left atrium.
Results:
No postoperative complications or deaths occurred. Mean ± SD operation time and mean cardiopulmonary bypass time were 267.2 ± 44.6 and 156.1 ± 33.6 min, respectively. These patients were extubated within the first 5 hours, and the volume of blood drainage on the first day was less than 80 mL. Four days after surgery, patients did not need analgesics and were able to return to normal activities 1 week postoperatively.
Conclusions:
Totally endoscopic operation for ASD closure on beating heart is safe, with short recovery period, and surgical scars are of high cosmetic value, especially in a woman and girl.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
... Hence, it is supposed that with the usage of CDI, we will get a faster and more effective de-airing procedure, and above all, a better organ protection against gaseous embolism. The protection for myocardium and cerebrum of CDI has been reported since 1967 in open heart surgery (9).Although there are also some researchers opposed to CDI for the incompetence of organ protection, they suppose that an insufficient de-airing was not the major source of gaseous emboli (10). What is more, someone reported that CDI caused hypercarbia (11,12). ...
... We identified a total of 335 citations through our search strategy. After the screen process, four articles were identified and fulfilled inclusion criteria (10,(13)(14)(15). Details of study selection are shown in Fig. 1. ...
... Three studies provided data on neurological complications (10,13,15), one of the three studies offered sorted cerebral events data (15), and thus we amalgamated them as total neurological complications. The overall pooled RR for neurological complications was 1.59, 95% CI = [0.57, ...
In spite of widespread application around the world, there has been controversy on the cerebral and cardiac protection efficacy of carbon dioxide insufflation (CDI) during open heart surgery. To make a comprehensive evaluation, we screened all relevant published randomized controlled trials to perform the first systematic review and meta-analysis for CDI during open heart surgery. We searched PubMed, EMBASE, the Cochrane Controlled Clinical Trial register, WANFAN, CQVIP, and CNKI database for published articles. Randomized controlled trials were included when the research provided data of neurological complications postoperatively, creatinine kinase, MB isoenzyme (CK-MB) on the first postoperative day, or all-cause mortality. We chose a fixed-effects model when the trials showed low heterogeneity, otherwise a random effects model was used. The quality of studies was assessed by modified Jadad scale. Four studies were included in this meta-analysis. The overall pooled relative risk (RR) for neurological complications was 1.59, 95% confidence interval (CI) = [0.57, 4.46], and the z-score for overall effect was 0.89 (P = 0.37). The standardized mean difference of the CK-MB between groups was 1.15, 95% CI = [-1.27, 3.56], and the z-score for overall effect was 0.93 (P = 0.35). The overall pooled RR for all-cause mortality was 0.5, 95% CI = [0.16, 1.64], and the z-score for overall effect was 1.14 (P = 0.25). There was no significant difference between groups. Because of the insufficiency of powerful evidences, the cerebral and cardiac protection efficacy of CDI during open heart surgery needs to be further verified by more high-quality trials.
... surgery. 173 Rather than intracardiac gas volume, the main predictor of cognitive decline in this study was atheromatous vascular disease. 173 Microemboli can also be detected by postoperative diffusion-weighted magnetic resonance imaging (MRI) 174 though preoperative MRI scans are needed to differentiate new microemboli from prior lesions. ...
... 173 Rather than intracardiac gas volume, the main predictor of cognitive decline in this study was atheromatous vascular disease. 173 Microemboli can also be detected by postoperative diffusion-weighted magnetic resonance imaging (MRI) 174 though preoperative MRI scans are needed to differentiate new microemboli from prior lesions. The percentage of cardiac surgery patients with detectable microemboli vastly outnumber the percentage with clear postoperative stroke(s). ...
For half a century, it has been known that some patients experience neurocognitive dysfunction after cardiac surgery; however, defining its incidence, course, and causes remains challenging and controversial. Various terms have been used to describe neurocognitive dysfunction at different times after cardiac surgery, ranging from "postoperative delirium" to "postoperative cognitive dysfunction or decline." Delirium is a clinical diagnosis included in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Postoperative cognitive dysfunction is not included in the DSM-5 and has been heterogeneously defined, though a recent international nomenclature effort has proposed standardized definitions for it. Here, the authors discuss pathophysiologic mechanisms that may underlie these complications, review the literature on methods to prevent them, and discuss novel approaches to understand their etiology that may lead to novel treatment strategies. Future studies should measure both delirium and postoperative cognitive dysfunction to help clarify the relationship between these important postoperative complications.
... surgery. 173 Rather than intracardiac gas volume, the main predictor of cognitive decline in this study was atheromatous vascular disease. 173 Microemboli can also be detected by postoperative diffusion-weighted magnetic resonance imaging (MRI) 174 though preoperative MRI scans are needed to differentiate new microemboli from prior lesions. ...
... 173 Rather than intracardiac gas volume, the main predictor of cognitive decline in this study was atheromatous vascular disease. 173 Microemboli can also be detected by postoperative diffusion-weighted magnetic resonance imaging (MRI) 174 though preoperative MRI scans are needed to differentiate new microemboli from prior lesions. The percentage of cardiac surgery patients with detectable microemboli vastly outnumber the percentage with clear postoperative stroke(s). ...
For half a century, it has been known that some patients experience neurocognitive dysfunction after cardiac surgery; however, defining its incidence, course, and causes remains challenging and controversial. Various terms have been used to describe neurocognitive dysfunction at different times after cardiac surgery, ranging from “postoperative delirium” to “postoperative cognitive dysfunction or decline.” Delirium is a clinical diagnosis included in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Postoperative cognitive dysfunction is not included in the DSM-5 and has been heterogeneously defined, though a recent international nomenclature effort has proposed standardized definitions for it. Here, the authors discuss pathophysiologic mechanisms that may underlie these complications, review the literature on methods to prevent them, and discuss novel approaches to understand their etiology that may lead to novel treatment strategies. Future studies should measure both delirium and postoperative cognitive dysfunction to help clarify the relationship between these important postoperative complications. (Anesthesiology 2018; XXX: 00-00)
... AF as cause of microembolism is considered the most important factor for cognitive dysfunction after cardiac surgery [25]. Although previous findings point to the higher impact of solid microemboli compared with gaseous microemboli on the late postoperative neurocognitive decline [26], similar pathways for early postoperative delirium are yet unknown. Whereas ateromatous microembolism is rather related to age, aortic cannulation and clamping [27], opening of the cardiac chambers for valve/aortic surgery may subject the brain to additional air microembolism. ...
Objectives:
The pathophysiology of delirium after cardiac surgery is complex. The present study aims to determine perioperative risk factors and construct a scoring system for postoperative delirium based on the type of surgery.
Methods:
Three hundred patients undergoing coronary artery bypass grafting (CABG; n = 150) or valve and/or aortic surgery ± CABG (n = 150) were retrospectively evaluated.
Results:
The incidence of delirium (32%) was similar in subgroups (28.7% and 33.33%, P = 0.384). Delirium patients were older [71.3 (standard deviation: 8.5) vs 66.6 (standard deviation: 9.5), P < 0.001; 70.0 (standard deviation: 9.6) vs 62.5 (standard deviation: 12.6), P < 0.001] and required more packed red blood cell units [2.1 (standard deviation: 2.1) vs 4.2 (standard deviation: 4.0), P < 0.001; 2.4 (standard deviation: 3.3) vs 5.4 (standard deviation: 5.9), P < 0.001] and fresh frozen plasma units [6.1 (standard deviation: 2.9) vs. 8.0 (standard deviation: 4.2), P < 0.001; 6.3 (standard deviation: 3.4) vs 10.8 (standard deviation: 7.2), P < 0.001] in CABG and valve/aortic subgroups, respectively. Delirium was associated with longer operation time [298.3 (standard deviation: 98.4) vs 250.6 (standard deviation: 67.8) min, P < 0.001], cardiopulmonary bypass (CPB) time [171.5 (standard deviation: 54.9) vs 140.98 (standard deviation: 45.8) min, P < 0.001] and cardiac arrest time [112 (standard deviation: 35.9) vs 91.9 (standard deviation: 28.6), P < 0.001] only in the valve/aortic group (versus non-delirium). Multivariate regression analysis identified an association between delirium and age [odds ratio: 1.056 (95% confidence interval: 1.002-1.113), P = 0.041], CPB time [odds ratio: 1.1014 (95% confidence interval: 1.004-1.025), P = 0.007], fresh frozen plasma transfusion [odds ratio: 1.127 (95% confidence interval: 1.006-1.262), P = 0.039] and atrial fibrillation [odds ratio: 4.801 (95% confidence interval: 1.844-12.502), P < 0.001] after valve/aortic surgery (area under the curve 0.835, P < 0.001) and between delirium and age [odds ratio: 1.089 (95% confidence interval: 1.023-1.160), P = 0.007] and ventilation time [odds ratio: 1.068 (95% confidence interval: 1.026-1.113), P = 0.001] after isolated CABG (area under the curve 0.798, P < 0.001). The cross-validation of the results by k-fold logistic regression revealed for the entire patient cohort an overall average accuracy of the prediction model of 0.764, with a false-positive rate of 0.052 and a false-negative rate of 0.18.
Conclusions:
Age, CPB time, ventilation, transfusion and atrial fibrillation are differently associated with delirium depending on the operative characteristics. Optimization of intraoperative parameters and use of risk calculators may enable early institution of pharmacotherapy and improve overall outcome after cardiac surgery.
... To reduce the nitrogen content, in order to prevent gas embolism, the administration of CO 2 in the operative field during "open chamber" cardiac surgery is a widespread clinical practice due to the higher molecular weight of the CO 2 and consequently it reduces the nitrogen percentage in the heart chambers. 8 There are mini-invasive extra-corporeal circuits (MiECC, Figure 2) that do not have a venous reservoir and use a closed bag for volume management. This strategy is the "conventional" ECC in some European regions, but in our paper we'll use the denomination conventional/standard for the "open reservoir" approach. ...
The inflammatory response in cardiac surgery using extracorporeal circulation (ECC) has been widely discussed in the literature with analysis on cytokines released in humans; demonstrating manifold trigger causes. To mitigate this response—mainly linked to the contact and recognition by the blood of a “non-self” surface—many efforts have been made to make the circuits of the extra-corporeal circulation “biomimetics”; trying to emulate the cardio-vascular system. In other words, biomedical companies have developed many biocompatible products in order to reduce the invasiveness of the ECC. One of the techniques used to reduce the contact of blood with “nonself” surfaces is the “coating” of the internal surfaces of the ECC. This can be done with phospholipidic, electrically neutral, and heparin derivates with anticoagulant activity. The coating can be divided into two categories: the “passive coating” with Phosphorylcholine by biomedical companies and the administration of albumin added to the “priming” during the filling of the circuit by the perfusionist. Alternatively, we have the “active” coating: treatment of the internal surfaces in contact with the blood with neutral proteins and heparin. The latter are different according to the production company, but the aim is always to maintain high levels of systemic and local anticoagulation, inactivating the “contact” coagulation between the blood and the surfaces. A recent study demonstrates that the use of an “active coating” is associated with better preservation of the endothelial glycocalyx compared with “passive coating” circuits.
... 43 Carbon dioxide (CO 2 ) flow is used to fill the pleural cavity and reduce the volume of retained intracardiac gas usually is run at 0.5-1 l/min and, however, can be maintained at higher levels. 10.5-mm port placed in the fifth to seventh intercostal space at the midaxillary line is used for CO 2 gas insufflations and afterward also for cardiotomy suction (69,70) . ...
Minimally invasive techniques impose itself on cardiac surgery in order to collaborate and overcome the advance in new technology in cardiology and fit the patient demands "psychic, physical and cosmetic", However proper utilization of resource and comparable outcome had been detected. Minimally invasive mitral valve surgery "repair or replacement" was one of the recently explored by cardiac surgeons over the past 20 years
Merits of minimally invasive mitral valve surgery in well trained hands are enormous. The rather routine use of minimally invasive mitral valve surgery showed less surgical trauma with its sequel, less postoperative pain, less blood loss and usage, less ventilation time, less intensive care unit stay, and total hospital stay, also lower load on postoperative rehabilitation services, better utilization of resources, increase turn over, less cost, better cosmesis, and earlier resumption of activities. In addition to the expected lower postoperative complications which could be noted in conventional method
It was proved that stress response in minimally invasive surgery is much less than conventional. Stress hormones, including catecholamines, steroids and thyroxin were
lower in minimally invasive surgeries
The reported possible preoperative risks in conventional mitral valve surgery is more hazardous in minimally invasive, with special emphasis on atherosclerosis, as there is no enough room to deal with in addition to local mechanical femoral vessels especially retrograde thoracic aortic dissection as proved by transesophageal echo, so careful patient selection is crucial to avoid vascular complications from femoral artery cannulation and retrograde perfusion. The presence of any atheromatous debris in the ascending and descending aorta must rule out preoperatively
Aim of the Work
The aim of this study is to compare the early postoperative pain, cost, hospital stay, recovery speed, residual mitral regurgitation and pulmonary function between minimally invasive and conventional mitral repair.
... The only RCT that performed psychological testing at 6 weeks was not able to show the beneficial effects of CO 2 flooding, although a significantly lower amount of intracardiac gas was noted on the intraoperative TOE in all cardiac chambers at any measured time point in the CO 2 group compared to the control group. Furthermore, the de-airing time was significantly shorter in the CO 2 group (median 9 vs 12 min, respectively; P = 0.02) [143]. ...
... The only RCT that performed psychological testing at 6 weeks was not able to show the beneficial effects of CO 2 flooding, although a significantly lower amount of intracardiac gas was noted on the intraoperative TOE in all cardiac chambers at any measured time point in the CO 2 group compared to the control group. Furthermore, the de-airing time was significantly shorter in the CO 2 group (median 9 vs 12 min, respectively; P = 0.02) [143]. ...
... Furthermore, the de-airing time was significantly shorter in the CO 2 group (median 9 vs 12 min, respectively; P ¼ 0.02). 143 The technique used for administering CO 2 flooding is an important issue, because inefficient administration can result in up to 50% of the air remaining inside the thoracic cavity. 144 Ineffective de-airing may lead to conclusions that underestimate the potential benefits of CO 2 flooding. ...
... The CPB perfusion pressure which was greater than 50 mmHg was recommended in children to keep aortic valve from opening [16]. CO 2 which has strong ability to dissolve in water has been shown to play an important role in preventing air embolism and can replace aortic root needle [17,18]. With these principles, we have successfully performed ASD repair on beating heart for more than 150 patients (included small children and adults). ...
Objective
To evaluate the effectiveness and safety of right anterolateral mini-thoracotomy without inferior vena cava (IVC) cannulation for closing atrial septal defect (ASD) in small children.
Methods
From February 2016 to August 2017, 10 patients (the mean age was 18.5 ± 10.1 months and the mean weight was 8.3 ± 2.1 kg) underwent ASD closure via right anterolateral mini-thoracotomy. The superior vena cava cannula was placed through the right internal jugular vein. A 3–4 cm incision was made on the right chest. The pleural and pericardial cavities were filled with CO2 and the heart was beating during the surgery. Blood returned from IVC was drained by a right heart sucker. All ASDs were closed using artificial patch, continuous suture. Mean follow-up was 18 months (range, 15–22 months).
Results
No post-operative complications or deaths occurred. Mean operation time and mean cardiopulmonary bypass time were 140.5 ± 27.8 min and 50.3 ± 16.5 min, respectively. These patients were extubated within the first 6 h. The intensive care unit stay time and the post-operative hospital stay time were 19.6 ± 2.6 h and 7.1 ± 1.2 days, respectively. Follow-up transthoracic echocardiography showed no residual shunts or lung atelectasis.
Conclusions
The right anterolateral mini-thoracotomy without IVC cannulation is feasible for repairing ASD in small children. This technique is effective and safe and can be used as a therapeutic option for ASD.
... However, the behavior of carbon dioxide in the actual operating field (ie, open thorax) has not been well studied. 2,3 In the present study, Vandenberghe and colleagues 1 successfully visualized the current of carbon dioxide using a Charged Coupled Device camera and the Schlieren technique. They demonstrated that carbon dioxide behaviors varied depending on the diffusor types, gas delivery flow rate, hand motions, and use of suction in the field. ...
... We prevent this complication based on the following rules: (1) maintaining the arterial line pressure >50 mmHg throughout the repair of ASD, (2) filling the pericardial and the pleural space with CO 2 with a pump rate of 0.5 l/min, and (3) inflating the lung to remove the air from the left atrium when completing the repair. The use of CO 2 in surgery on the beating heart has been shown to play an important role in preventing air embolism and can replace aortic root needle [9,10]. These rules have been applied successfully in >120 patients diagnosed with ASD undergoing TES without aortic root needle. ...
Introduction
Although totally endoscopic surgery (TES) has been widely applied for the treatment of atrial septal defect (ASD), small children receive few benefits from this technique due to risks of the femoral cannulation.
Case presentation
A 23-month-old boy, weighing 10.5 kg, with the diagnosis of sinus venosus ASD underwent successful repair by TES. We performed this surgery through 4 small trocars (one 12 mm trocar and three 5 mm trocars), without robotic assistance. In this case, we inserted the arterial cannula directly into the ascending aorta instead of the femoral artery (FA). The defects were repaired on the beating heart with CO2 insufflation.
Discussion
Femoral cannulation in small children pose some risks, such as increased arterial line pressure, critical lower limb ischaemia, and post-operative iliac or femoral arterial stenosis. Putting the arterial cannula directly into the ascending aorta is a good solution but is difficult to be performed through TES, especially in small children. The major concern of operating on the beating heart is the air embolism, which requires special preventative methods.
Conclusion
Transthoracic aortic cannulation may facilitate TES in small children. However, the safety and efficacy of this approach needs to be validated by larger studies preferably randomised controlled trials.
... Arterial anastomosis models demonstrated that the main reasons for lumen stenosis are smooth muscle cell proliferation and intimal damage [1][2][3]. The pathological cause of restenosis and endothelial cell proliferation is migration of proliferated smooth muscle cells from media to intima [3]. ...
Introduction
Use of carbon dioxide (CO2) insufflation (CDI) on the surgical field during heart surgery has become widespread, and in some units routine.
Aim
To assess the effects of CDI on endothelial dysfunction in a carotid artery model in rabbits.
Material and methods
Twelve randomly selected rabbits were divided into two groups. Right carotid arteries of the animals were transected and sutured with running suture technique. Then, 1 l/min CO2 insufflation was initiated with a 45° angle. In the control group, the anastomotic field was irrigated with 0.1 ml/s flow of 0.9% saline. At day 28, the carotid artery segments were removed and prepared for histological specimens.
Results
In the cross-sections of the control group vessel samples, thickening of the tunica intima was observed. Scoring the quantity of endothelial nitric oxide synthase (e-NOS) and α-smooth muscle actin (α-SMA) positive staining revealed a nonsignificant difference between the experimental groups (p = 0.07). In the CO2 group, the intimal hyperplasia (p = 0.2) and the thickness of the tunica media (p = 0.2) were indistinguishable when compared to the control group. The mean luminal diameters and luminal areas of the experimental groups were all evaluated by histomorphometry and a significant differences was found between luminal areas (p = 0.016). On the other hand, no significant difference was found between mean luminal diameters (p = 0.055).
Conclusions
Our study indicated that CDI can affect endothelial cell damage and the mean luminal diameters.
... 4,[32][33][34][35][36] Moreover, the use of CO 2 atmosphere has been debatable. 37,38 Nevertheless, we believe that notwithstanding shortages in our randomization assumptions, our study still offers important insights that are relevant to surgical practice. ...
Introduction
The risk of air microembolism during cardiopulmonary bypass (CPB) is high and influences the postoperative outcome, especially in elderly patients. The use of carbon dioxide (CO2) atmosphere during cardiac surgery may reduce the risk of cerebral air microembolism. The aim of our study was to assess the influence of CO2 field flooding on microembolism-induced brain damage assessed by the level of S100ß protein, regarded as a marker of brain damage.
Materials and methods
A group of 100 patients undergoing planned mitral valve operation through median sternotomy using standard CPB was recruited for the study. Echocardiography was performed prior to and after the CPB. CO2 insufflation at 6 L/minute was conducted in the study group. Blood samples for S100ß protein analysis were collected after induction of anesthesia, 2 hours after aorta de-clamping, and 24 hours after operation.
Results
The S100ß level in blood plasma did not differ significantly between the study and the control group (0.13±0.08 µg/L, 1.12±0.59 µg/L, and 0.26±0.23 µg/L and 0.18±0.19 µg/L, 1.31±0.62 µg/L, and 0.23±0.12 µg/L, P=0.7, 0.14, and 0.78). The mean increase of the S100ß concentration was 13% lower in the group with CO2 protection than in the control group (0.988 µg/L vs 1.125 µg/L), although statistically insignificant. Tricuspid valve annuloplasties (TVAs) had significant impact on the increase in S100ß concentration in the treatment group after 24 hours (TVA [−] 0.21±0.09 vs TVA [+] 0.42±0.42, P=0.05). In patients <60 years, there were significant differences in the S100ß level 2 and 24 hours after the procedure (1.59±0.682 µg/L vs 1.223±0.571 µg/L, P=0.048, and 0.363±0.318 µg/L vs 0.229±0.105 µg/L, P=0.036) as compared with younger patients.
Conclusion
The increase in S100ß concentration was lower in the group with CO2 protection than in the control group. Age and an addition of TVA significantly influenced the level of S100ß concentration in the tests performed 2 hours after aortic clamp release.
... [2][3][4][5] Potential alternative explanations for cognitive decline include the effects of age, pre-existing cognitive decline, and pre-existing cardiovascular disease, combined with peri-operative stressors, such as the use of anaesthesics, haemodynamic changes during cardiopulmonary bypass, impact of particulate emboli, impaired regulation of cerebral blood flow, and inflammatory responses. Although studies of decompression sickness [1] and experiments on animals [6] clearly demonstrate the potential for clinical symptoms if bubbles are present in sufficient quantities, interventional trials conducted in a cardiac surgery setting find no cognitive benefit in reducing the volume of air entering the bloodstream during surgery [3,7]. Since there is currently no method for determining the size distribution and volume of bubbles reaching the cerebral circulation, it is difficult to assess whether quantities of air typically introduced during surgery are high enough to result in cognitive decline. ...
Background
Thousands of air bubbles enter the cerebral circulation during cardiac surgery, but whether high numbers of bubbles explain post-operative cognitive decline is currently controversial. This study estimates the size distribution of air bubbles and volume of air entering the cerebral arteries intra-operatively based on analysis of transcranial Doppler ultrasound data.
Methods
Transcranial Doppler ultrasound recordings from ten patients undergoing heart surgery were analysed for the presence of embolic signals. The backscattered intensity of each embolic signal was modelled based on ultrasound scattering theory to provide an estimate of bubble diameter. The impact of showers of bubbles on cerebral blood-flow was then investigated using patient-specific Monte-Carlo simulations to model the accumulation and clearance of bubbles within a model vasculature.
Results
Analysis of Doppler ultrasound recordings revealed a minimum of 371 and maximum of 6476 bubbles entering the middle cerebral artery territories during surgery. This was estimated to correspond to a total volume of air ranging between 0.003 and 0.12 mL. Based on analysis of a total of 18667 embolic signals, the median diameter of bubbles entering the cerebral arteries was 33 μm (IQR: 18 to 69 μm). Although bubble diameters ranged from ~5 μm to 3.5 mm, the majority (85%) were less than 100 μm. Numerous small bubbles detected during cardiopulmonary bypass were estimated by Monte-Carlo simulation to be benign. However, during weaning from bypass, showers containing large macro-bubbles were observed, which were estimated to transiently affect up to 2.2% of arterioles.
Conclusions
Detailed analysis of Doppler ultrasound data can be used to provide an estimate of bubble diameter, total volume of air, and the likely impact of embolic showers on cerebral blood flow. Although bubbles are alarmingly numerous during surgery, our simulations suggest that the majority of bubbles are too small to be harmful.
Introduction: Perioperative neurocognitive disorders(PND)is one of the most common postoperative complications among elderly patients (above 65 years old) undergoing cardiac surgery. However, thus far, there have not been any effective therapies for managing PND. Recent research has shown that repetitive transcranial magnetic stimulation (rTMS) alters brain plasticity and improves cognitive function in several neurodegenerative disorders and psychiatric disorders. However, the potential benefits of rTMS in reducing PND in patients undergoing cardiac surgery have not been investigated. Therefore, the current protocol is designed to determine whether rTMS can reduce the incidence of PND in patients undergoing cardiac surgery.
Methods and analysis: The study will be a single-blinded, randomized controlled trial. Participants undergoing elective cardiac surgery will be randomized to receive either rTMS or sham stimulation with a focal figure of eight coils over the right dorsolateral prefrontal cortex. A series of neuropsychological tests will be completed to evaluate cognitive function in surgery patients before, on day 7, and on day 30 after cardiac surgery. The primary outcome is the prevalence of PND in cardiac surgery patients. The secondary outcomes will be the incidence of postoperative delirium, pain, sleep quality, depressive symptoms, activities of daily living, length of hospital stay and ICU length of stay, and rate of complication and mortality during the hospital stay.
Ethics and dissemination: Beijing Chaoyang Hospital Ethics Committee approved this study and has number 2022-ke-487. It is registered with Clinical Trials (trial number NCT 05668559). Informed consent must be provided by all participants. The study result will be published in a peer-reviewed journal.
Trial registration number: NCT05668559
Objective
To evaluate the safety and efficacy of the Hanoi ASD procedure, which is totally endoscopic surgery for atrial septal defect (ASD) repair on beating heart. In addition, the present study also aimed to analyze the learning curve for this procedure.
Methods
From May 2016 to February 2023, 198 consecutive ASD patients weighing ≥20 kg were enrolled in the retrospective study. The Hanoi ASD procedure includes (1) unilateral or bilateral femoral arterial cannulation; (2) two or three 5 mm trocars and a 15 mm port; (3) ASD repair on beating heart, preventing air embolism with CO 2 insufflation and keeping the left atrium full of blood; and (4) not snaring the inferior vena cava. Cumulative sum (CUSUM) analysis was used to evaluate the cardiopulmonary bypass (CPB) and operation time learning curves. Variables among the learning curve phases were compared.
Results
The CPB and operation times were 90 (72 to 115) min and 180 (150 to 220) min, respectively. Total drainage volume was 190 (120 to 290) mL. No endoscopic failure or major complications were recorded. After excluding factors causing bias, the CUSUM CPBtime analysis for the remaining 131 patients included 3 phases. Phase 1 was the initial learning period (cases 1 to 34), phase 2 represented the technical competence period (cases 35 to 54), and phase 3 was the challenging period (cases 55 to 131).
Conclusions
The Hanoi ASD procedure is safe and feasible for repairing ASD in patients weighing ≥20 kg. According to the learning curve analysis, 34 cases were required to achieve technical efficiency, and 54 cases were required to address highly challenging cases.
Introduction:
Thoracic endovascular aortic repair (TEVAR) carries a 3%-6.1% stroke risk, including risk of 'silent' cerebral infarction (SCI). Stent-grafts are manufactured in room air and retain air. Instructions for use recommend saline flushing to 'de-air' the system prior to insertion, but substantial amounts of air are released when deploying them, potentially leading to downstream neuronal injury and SCI. Carbon dioxide (CO2) is more dense and more soluble in blood than air, without risk of bubble formation, so could be used in addition to saline to de-air stents. This pilot trial aims to assess the feasibility of a full-scale randomised controlled trial (RCT) investigating the neuroprotective benefit against SCI with the use of CO2-flushed aortic stent-grafts.
Methods and analysis:
This is a multicentre pilot RCT, which is taking place in vascular centres in the UK, USA and New Zealand. Patients identified for TEVAR will be enrolled after informed written consent. 120 participants will be randomised (1:1) to TEVAR-CO2 or TEVAR-saline, stratified according to TEVAR landing zone. Participants will undergo preoperative neurocognitive tests and quality of life assessments, which will be repeated at 6 weeks, or first outpatient appointment, and 6 months. Inpatient neurological testing will be performed within 48 hours of return to level 1 care for clinical stroke or delirium. Diffusion-weighted MRI will be undertaken within 72 hours postoperatively (1-7 days) and at 6 months to look for evidence and persistence of SCI. Feasibility will be assessed via measures of recruitment and retention, informing the design of a full-scale trial.
Ethics and dissemination:
The study coordination centre has obtained approval from the London Fulham Research Ethics Committee (19/LO/0836) and Southern Health and Disability Ethics Committee (NZ) and UK's Health Regulator Authority (HRA). The study has received ethical approval for recruitment in the UK (Fulham REC, 19/LO/0836), New Zealand (21/STH/192) and the USA (IRB 019-264, Ref 378630). Consent for entering into the study will be taken using standardised consent forms by the local study team, led by a local PI. The results of the trial will be submitted for publication in an open access journal.
Trial registration number:
NCT03886675.
Since cardiac surgery was first practiced, retained intracardiac air has been an important problem. The effects of air embolism during heart operations and methods intended to prevent it have long been studied. Although the introduction of ultrasound visualization has allowed for the detection of air and guided deairing procedures, adequate air removal is not always attained due to the individual preferences of each surgeon. Air removal procedures appear to vary a great deal among institutions, and are not necessarily based on firm scientific evidence. To address this clinical need for all MICS procedures, we are developing the cardiac deairing system (CDS), which can be introduced easily not only through small incisions, but also through keyhole (stab) incisions and ports placed through the chest. The CDS will use the regular air and vacuum supplies that are standard in the operating room to be activated. In this chapter, we describe the development of the CDS and report our in vitro research and testing and in vivo feasibility study to test the design features and characteristics of this technology.
Background:
Flooding the surgical field with dry cold CO2 during open-chamber cardiac surgery has been used to mitigate air entrainment into the systemic circulation. However, exposing epithelial surfaces to cold, dry gas causes tissue desiccation. This randomised controlled study was designed to investigate whether the use of humidified warm CO2 insufflation into the cardiac cavity could reduce pericardial tissue damage and the incidence of micro-emboli when compared to dry cold CO2 insufflation.
Methods:
Forty adult patients requiring elective open-chamber cardiac surgery were randomised to have either dry cold CO2 insufflation via a standard catheter or humidified warm CO2 insufflation via the HumiGard device. The primary endpoint was biopsied pericardial tissue damage, assessed using electron microscopy. We assessed the percentage of microvilli and mesothelial damage, using a damage severity score (DSS) system. We compared the proportion of patients who had less damage, defined as DSS < 2. Secondary endpoints included the severity of micro-emboli, by visual assessment of bubble load on transoesophageal echocardiogram; lowest near infrared spectroscopy; total de-airing time; highest cardio-pulmonary bypass sweep speed; hospital length of stay and complications.
Results:
A higher proportion of patients in the humidified warm CO2 group displayed conserved microvilli (47% vs 11%, p=0.03) and preserved mesothelium (42% vs 5%, p=0.02) compared to the control group. There were no differences in the secondary outcomes.
Conclusions:
Humidified warm CO2 insufflation significantly reduced pericardial epithelial damage when compared to dry cold CO2 insufflation in open-chamber cardiac surgery. Further studies are warranted to look into its potential clinical benefits.
The brain is amazingly interesting and complex. As neuroscience progresses, we gain a broader understanding of specialized regional activity, chemistry and unique interconnections that makes us the fascinating and diverse organisms that we are. However, that same complexity makes assessment of brain function and injury causality difficult. A small embolic injury in the motor cortex results in substantial impact on one’s ability to move and function, while a much larger injury in silent areas of the cortex may go unnoticed. Furthermore, the brain is not static over the decades of life. In particular, the elderly are at increased risk of neurocognitive consequences of stress and injury due to reduced functional reserve. While the brain is amazingly complex on it’s own, it is not an isolated organ and our body’s broader response to stress or injury, including coagulation and inflammatory changes targeted toward a distant injury, may also impact the brain and the integrity of the connection between the brain and our body (the blood brain barrier). Finally, we add anesthesia and surgery into this complex mix of factors that can alter the ability to respond and function. This is particularly important, as anesthesia and surgery have progressed substantially in safety, such that older and sicker patients may now undergo increasingly complex procedures with low probability of morbidity and mortality. However, as previously noted the elderly are particularly susceptible to neurocognitive sequellae. The following chapter discusses our evolving understanding of postoperative cognitive dysfunction and delirium.
Multiple advances in perioperative techniques, especially the maturation of cardiopulmonary bypass, have allowed the practice of cardiac surgery to develop rapidly. Despite these advances that have enabled contemporary cardiac surgery to address a diverse range of cardiac pathologies, neurological injury, ranging from delirium to stroke, has persisted as a relatively common and important complication after cardiac surgery. As a result, extensive research has explored the etiologies of neurologic injury after cardiac surgery to identify interventions that may reduce its incidence. Although the strategies for neuroprotection have some similarities across the types of cardiac surgery, many differences remain as a result of varied etiologies for neurological injury. For the sake of clarity, this chapter will approach neurologic injury and neuroprotective strategies by the type of cardiac procedure in the following sections: cardiac surgery with cardiopulmonary bypass; off-pump coronary artery bypass grafting; transcatheter aortic valve replacement and thoracic aortic surgery.
A 56-year-old man who had twice previously undergone orthotopic heart transplantation was admitted with dyspnea and heart failure symptoms. A biopsy excluded rejection. Left heart catheterization revealed a coronary cameral fistula. After the patient was given mild diuretics, his condition improved. No significant fistula flow was detected, and he was discharged. Several months later, the patient was readmitted with worsening chest pain and dyspnea. Left ventricular end-diastolic pressure and flow through the fistula were increased. To correct the coronary cameral fistula, we performed a coil embolization without complications. Several months later at follow-up, the patient’s symptoms had resolved, and his left ventricular end-diastolic pressure had normalized. We conclude that coronary fistulas may be caused by trauma to the heart during the de-airing process, which may be prevented in the future with the development of safer and more effective de-airing techniques.
Objective:
Carbon dioxide field flooding during open-heart surgery is intended to avoid blood-air contact, bubble formation, and embolism, and therefore potential neurologic and other ischemic complications. The inert gas is invisible, and thus its use and effectiveness are heavily debated. We intended to provide better insight in the behavior of the gas via direct concentration measurements and visualization of the gas cloud.
Methods:
A transparent rectangular model of the open thorax was created, foreseen with carbon dioxide concentration sensors in 2 locations (atrial and aortic incisions), and placed in an optical test bench that amplifies the diffraction gradients. Six different commonly used carbon dioxide diffusors (3 commercial, 3 improvised) were tested with different flow rates of gas delivery (1, 4, 7, 10 standard liter per minute [SLPM]) and combined with the application of suction.
Results:
The imaging reveals that commercially available diffusors generally create less turbulent flow than improvised diffusors, which is supported by the concentration measurements where improvised diffusors cannot generate a 100% carbon dioxide atmosphere at the aorta incision location. The atrial incision is easier to protect: 0% air with all commercial devices for all flow rates greater than 1 SLPM. A flow rate of 1 SLPM does not create an inert atmosphere with any device.
Conclusions:
The optically observed carbon dioxide atmosphere is unstable and influenced by many factors. The device used for diffusion and the flow rate are important determinants of the maximum gas concentration that can be achieved, as is the location where this is measured.
In this chapter anatomy, diagnostic features, and surgical approaches for congenital anomalies of atrial septum, atrioventricular valves, and pulmonary veins are described.
Abstract (Word Count: 221)
Objective(s)
Despite the widespread use of carbon dioxide insufflation (CDI) in cardiac surgery, there is still paucity of evidence to prove its benefit in terms of neurological protection. Therefore, we conducted a meta-analysis of available randomized controlled trials (RCT) comparing CDI versus standard de-airing manoeuvres.
Methods
Electronic searches were performed to identify relevant RCTs. Primary outcomes investigated were postoperative stroke, neurocognitive deterioration (NCD), and in-hospital mortality. Risk difference (RD) was used as summary statistic. Pooled estimates were obtained by means of random-effects model to account the possible clinical diversity and methodologic variation between studies.
Results
A total of 8 studies were identified with 668 patients randomized to CDI (n=332) versus standard de-airing manoeuvres (n=336). In hospital mortality was 2.1% versus 3.0% in the CDI and control group respectively (RD 0%; 95%CI -2% to 2%; P=0.87; I2=0%). Incidence of stroke was similar between the two groups (1.0% versus 1.2% in the CDI and control group respectively (RD 0%; 95%CI -1% to 2%; P=0.62; I2=0%). NCD rate was 12% versus 21% in the CDI and control group respectively but this difference was not statistically significant (RD: -7%; 95%CI -022% to 8%; P=0.35; I2=0%).
Conclusions
The present meta-analysis did not find any significant protective effect from the use CDI when compared with manual de-airing manoeuvres in terms of clinical outcomes including postoperative neurocognitive decline.
Objectives:
We previously described and showed that the method for cardiac de-airing involving: (1) bilateral, induced pulmonary collapse by opening both pleurae and disconnecting the ventilator before cardioplegic arrest and (2) gradual pulmonary perfusion and ventilation after cardioplegic arrest is superior to conventional de-airing methods, including carbon dioxide insufflation of the open mediastinum. This study investigated whether one or both components of this method are responsible for the effective de-airing of the heart.
Methods:
Twenty patients scheduled for open, left heart surgery were randomized to two de-airing techniques: (1) open pleurae, collapsed lungs and conventional pulmonary perfusion and ventilation; and (2) intact pleurae, expanded lungs and gradual pulmonary perfusion and ventilation.
Results:
The number of cerebral microemboli measured by transcranial Doppler sonography was lower in patients with open pleurae 9 (6-36) vs 65 (36-210), p=0.004. Residual intra-cardiac air grade I or higher as monitored by transesophageal echocardiography 4-6 minutes after weaning from cardiopulmonary bypass was seen in few patients with open pleurae 0 (0%) vs 7 (70%), p=0.002.
Conclusions:
Bilateral, induced pulmonary collapse alone is the key factor for quick and effective de-airing of the heart. Gradual pulmonary perfusion and ventilation, on the other hand, appears to be less important.
Mitral valve (MV) disease is the most prevalent form of heart valve disease with an age-related increase in incidence. Surgical valve repair or replacement is the only treatment for mitral regurgitation with defined clinical success. The conventional surgical correction of significant valvular regurgitation usually consists of repair or replacement of the MV through a median full-length sternotomy, which remains the “classic” approach for the majority of procedures involving the MV. From early experience in MV surgery, several types of surgical access were established: through left and right anterolateral thoracotomy for closed and correspondingly for open mitral commissurotomy, from right parasternal access with rib resection, and through a full median sternotomy. These methods have been studied and evaluated by cardiac surgeons through the years to establish known benefits and drawbacks. Factors influencing the choice of access have included improved working field exposure, visualization, ergonomics and cosmetic outcomes, and superior preservation of the structural and morphological integrity of tissues. Applying technological development to successful basic cardiac surgical techniques has led to the introduction of minimally invasive approaches to cardiac valve procedures. Today, as an alternative to conventional surgical approaches, the minimally invasive surgical technique in the treatment of heart valve diseases has become a rapidly evolving field offering several advantages including reduced postoperative pain, decreased morbidity and mortality, faster recovery, shorter hospital stays, reduced costs, and improved cosmetic appearance at the incision site. Currently, the most innovative minimally invasive techniques include port-access valve surgery, achieved through a small minithoracotomy and performed as either direct-vision, video-assisted, or robotically assisted valve surgery through the right minithoracotomy. In our institution, port-access surgery concepts and technique was initially introduced for minimally invasive repair and replacement in isolated MV diseases. Today, we perform the majority of our isolated mitral procedures and also concomitant tricuspid and/or aortic valve surgeries through the minithoracotomy using direct and/or video-assisted approach. In this chapter, we will focus on the minimally invasive surgical techniques used in surgery today for performing MV surgery through a right minithoracotomy.
The study aimed to investigate patient and spouse perception of cognitive functioning 1 to 2 years after coronary artery bypass grafting.
Seventy-six married patients who had undergone coronary artery bypass grafting were selected and sex- and age-matched with 75 concurrent married patients who had undergone percutaneous transluminal coronary angioplasty. Couples received a letter of explanation and then completed telephone interviews. Forty-seven questions assessed memory, concentration, general health, social functioning, and emotional state. Response choices were: improved, unchanged, or deteriorated function after coronary artery bypass grafting/percutaneous transluminal coronary angioplasty.
Patients who had undergone coronary artery bypass grafting did not differ in subjective ratings on any measure from patients who had undergone percutaneous transluminal coronary angioplasty. There were no differences between spouses in the respective groups; spouse ratings also did not differ from patient ratings. Only in memory function did patients and spouses report a postprocedural decline.
No subjective differences were found in patients who had undergone either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. Spouse ratings agreed with each other and with patient ratings. Positive correlations were found between the questionnaire factors, suggesting that perceived health and well-being are associated with subjective cognition.
This paper compares four techniques used to assess change in neuropsychological test scores before and after coronary artery bypass graft surgery (CABG), and includes a rationale for the classification of a patient as overall impaired.
A total of 55 patients were tested before and after surgery on the MicroCog neuropsychological test battery. A matched control group underwent the same testing regime to generate test-retest reliabilities and practice effects. Two techniques designed to assess statistical change were used: the Reliable Change Index (RCI), modified for practice, and the Standardised Regression-based (SRB) technique. These were compared against two fixed cutoff techniques (standard deviation and 20% change methods).
The incidence of decline across test scores varied markedly depending on which technique was used to describe change. The SRB method identified more patients as declined on most measures. In comparison, the two fixed cutoff techniques displayed relatively reduced sensitivity in the detection of change.
Overall change in an individual can be described provided the investigators choose a rational cutoff based on likely spread of scores due to chance. A cutoff value of > or =20% of test scores used provided acceptable probability based on the number of tests commonly encountered. Investigators must also choose a test battery that minimises shared variance among test scores.
Background. The presence of ascending aortic atheroma is a known risk for systemic emboli or early saphenous vein graft failure if unrecognized at the time of cardiopulmonary bypass.Methods. This study prospectively compared intraoperative omniplane transesophageal echocardiography (TEE) and epiaortic ultrasound (EAU) images in 22 patients (6 women, 16 men, age 66 ± 8 years) before surgical manipulation of the ascending aorta. Atheroma lesion severity was scored: 1 = normal, 2 = nonprotruding intimal thickening (> 2 mm), 3 = atheroma less than 4 mm ± Ca++, 4 = atheroma greater than or equal to 4 mm ± Ca++, and 5 = any size mobile or ulcerated lesion ± Ca++. The ascending aorta between the aortic valve and innominate artery was divided into proximal, middle, and distal segments. A total of 66 segments were evaluated.Results. Although the overall agreement of scores between procedures was 75.8%, significantly more lesions were identified by EAU (15) than by TEE (5) (p < 0.03). TEE failed to identify lesions in the middle and distal segments of the aorta with a score of more than 3.Conclusions. Although atheromatous lesions were identified in the ascending aorta by both ultrasound modalities, the results suggest that intraoperative EAU may have an advantage over TEE for surgeons assessing target sites for surgical procedures involving the ascending aorta.
Objectives:
Our study was designed to determined the significance of aortogenic embolism in an unselected autopsy collective.
Background:
Although embolism arising from atherosclerotic plaques in the aorta has been acknowledged, the role of aortic atheromatosis among other well known sources of embolism remains to be further clarified.
Methods:
We examined the proximal part of the arterial system with regard to the presence of atherosclerotic lesions as well as cardiac changes in 120 consecutive necropsy studies. Pathologic evidence of embolic events was recorded. Clinical and neuropathologic data were also surveyed in all patients.
Results:
Among atherosclerotic lesions, fibrous plaques (p < 0.05) and calcified (p < 0.0001) and ulcerated lesions (p < 0.0001) as well as thrombi (p < 0.005) were observed significantly more frequently in the aortic arch and in the descending aorta than in the ascending aorta, whereas fatty streaks were distributed uniformly. In 40 (33%) of the 120 patients, we found pathologic evidence of arterial embolization. Multiple logistic regression analysis revealed a significant correlation between embolism and complicated atherosclerotic plaques in the aortic arch (odds ratio [OR] 5.8, 95% confidence interval [CI] 1.1 to 31.7, p < 0.05), severe ipsilateral carotid artery disease (OR 3.1, 95% CI 3.1 to 45.3, p < 0.001) and atrial fibrillation (OR 3.5, 95% CI 1.1 to 9.9, p < 0.05).
Conclusions:
Complicated atherosclerotic plaques in the aortic arch represent an independent risk factor for systemic embolism similar to atrial fibrillation and severe atherosclerosis of the carotid arteries.
Background:
Open heart surgery is associated with a significant risk of cerebral and myocardial dysfunction, which is attributed in part to air embolism from incompletely deaired cardiac chambers. To evaluate the impact of carbon dioxide (CO2) insufflation to the thoracic cavity, a prospective randomized study was designed.
Methods:
A total of 62 elective patients were randomly assigned to CO2 insufflation (group I, n = 31) or control (group II, n = 31). According to the Parsonnet risk score, 16 patients in group I (52%) and 10 patients in group II (32%) were categorized as being at either high risk or extremely high risk.
Results:
In group II, perioperative mortality was 16.1% (5 patients); in group I, 1 patient died (ns). Creatine kinase MB isoenzyme, as a marker of myocardial damage, was more elevated in group I after surgery (38.0 +/- 4.1 vs 28.0 +/- 2.1, p = 0.02). Neurocognitive test scores did not reveal significant postoperative differences between groups.
Conclusions:
Although mortality was lower with CO2 insufflation, no benefit could be demonstrated for markers of cardiac ischemic damage or neurocognitive outcome in this high-risk population. As CO2 concentrations in the thoracic cavity did not necessarily reach anticipated levels, our method of application is in question.
The use of carbon dioxide (CO(2)) insufflation into the pericardial well has become widespread, and in some units routine. The rationale behind this practice is the fact that CO(2) is more soluble than air leading to fewer gaseous microemboli entering the bloodstream and being transferred to the brain or heart. However, the evidence that this reduces postoperative neurocognitive decline is scant. Although CO(2) insufflation is generally a safe procedure there are case reports of significant complications. The aim of this systematic review is to analyze the current evidence for this practice.
Short- and long-term cognitive declines after cardiac surgery with cardiopulmonary bypass have been reported, but the frequency, severity, nature, and etiology of postoperative cognitive changes have been difficult to quantify. Current studies have corrected the principal methodological shortcoming of earlier studies by including control groups, and have shown that while early postoperative cognitive decline does occur in some patients, it is generally mild and reversible by 3 months after surgery. Late cognitive changes do occur, but comparison with patients undergoing off-pump surgery or those being treated medically suggests that these changes are not specific to CABG or more specifically to the use of cardiopulmonary bypass.
Until now, little attention has been paid to the preoperative status of the patient awaiting cardiac surgery when investigating the effects of cardiac surgery on cognition. However, there is growing evidence that pre-bypass patients show poorer cognitive function than healthy subjects. This article reviews existing published evidence of poor cognitive function in pre-bypass patients by describing patient characteristics, providing an inventory of affected neurocognitive domains, discussing adequate control groups and proposing potential aetiological mechanisms of neuropsychological dysfunctioning. It is concluded that there is a growing need for future research into this important topic on cognitive dysfunctioning in candidates for coronary artery bypass grafting surgery.
This study examined the validity of the four standard psychological paradigms that have been operationally defined within
the CogState brief computerized cognitive assessment battery. Construct validity was determined in a large group of healthy
adults. CogState measures of processing speed, attention, working memory, and learning showed strong correlations with conventional
neuropsychological measures of these same constructs (r's = .49 to .83). Criterion validity was determined by examining patterns of performance on the CogState tasks in groups of
individuals with mild head injury, schizophrenia, and AIDS dementia complex. Each of these groups was impaired on the CogState
performance measures (Cohen's d's = −.60 to −1.80) and the magnitude and nature of this impairment was qualitatively and quantitatively similar in each group.
Taken together, the results suggest that the cognitive paradigms operationally defined in the CogState brief battery have
acceptable construct and criterion validity in a neuropsychological context.
Much attention in the literature has focused on the relationship between perioperative microemboli during cardiac and vascular surgery and postoperative cognitive decline. Transcranial Doppler ultrasonography (TCD) has been used to measure high-intensity transient signals (HITS), which represent microemboli during cardiac, vascular, and orthopedic surgery. The purpose of this study was to systematically examine the literature with respect to HITS and postoperative cognitive function.
Systematic PubMed searches identified articles related to the use of TCD and cognitive function in the surgical setting.
The literature remains largely undecided on the role of HITS and cognitive impairment after surgery, with most studies being underpowered to show a relationship. Although the cognitive effects of HITS may be difficult to detect, subclinical microemboli present potential harm, which may be modifiable.
TCD represents a tool for intraoperative cerebral monitoring to reduce the number of HITS during surgery.
Despite major advances in cardiopulmonary bypass technology, surgical techniques, and anesthesia management, central nervous system complications remain a common problem after cardiopulmonary bypass. The etiology of neuropsychologic dysfunction after cardiopulmonary bypass remains unresolved and is probably multifactorial. Demographic predictors of cognitive decline include age and years of education; perioperative factors including number of cerebral emboli, temperature, mean arterial pressure, and jugular bulb oxygen saturation have varying predictive power. Recent data suggest a genetic predisposition for cognitive decline after cardiac surgery in patients possessing the apolipoprotein E epsilon-4 allele, known to be associated with late-onset and sporadic forms of Alzheimer's disease. Predicting patients at risk for cognitive decline allows the possibility of many important interventions. Predictive power and weapons to reduce cellular injury associated with neurologic insults lend hope of a future ability to markedly decrease the impact of cardiopulmonary bypass on short-term and long-term neurologic, cognitive, and quality-of-life outcomes.
Microemboli to the cerebral circulation occur during cardiopulmonary bypass (CPB) and can contribute to postoperative neurologic dysfunction. Cerebral microemboli are known to occur during specific surgical interventions, but the source of a large proportion of emboli remains unexplained. We investigated whether interventions by the perfusionist could account for the appearance of cerebral microemboli.
Transcranial Doppler ultrasonography was used to continuously monitor the middle cerebral artery of 18 patients undergoing coronary artery bypass grafting. The CPB circuit consisted of a softshell venous reservoir, a hollow-fiber membrane oxygenator, and a 32-microm arterial filter. The mean embolic rate was calculated for three time periods: (1) during surgical interventions (aortic cannulation and decannulation, cross-clamp application and removal, CPB start and end, and start of cardiac ejection); (2) during perfusionist interventions (blood sampling and drug administration into the venous reservoir); and (3) during baseline (all other time periods during CPB).
Microemboli were detected in all patients (mean +/- standard deviation, 207+/-142 per patient, median, 132). The number of emboli per minute was significantly (p < 0.001) higher during perfusionist interventions (6.9+/-4.5) than during surgical interventions (1.5+/-1.5) or during baseline (0.4+/-0.5). Drug administration resulted in a higher embolic rate than blood sampling.
Interventions by the perfusionist account for a large proportion of previously unexplained cerebral microemboli during CPB. These emboli likely represent air bubbles that are not eliminated by the arterial line filter. Although further studies of additional types of CPB circuits are required, we believe that air in the venous reservoir should be avoided whenever possible to minimize the risk of neurologic injury.
The use of carbon dioxide for displacement of air in cardiac surgery can have potential adverse effects on blood gas strategies. Presented is a method of monitoring carbon dioxide in the cardiopulmonary bypass circuit and limiting the potential for severe hypercarbia during cardiopulmonary bypass.
The presence of ascending aortic atheroma is a known risk for systemic emboli or early saphenous vein graft failure if unrecognized at the time of cardiopulmonary bypass.
This study prospectively compared intraoperative omniplane transesophageal echocardiography (TEE) and epiaortic ultrasound (EAU) images in 22 patients (6 women, 16 men, age 66 +/- 8 years) before surgical manipulation of the ascending aorta. Atheroma lesion severity was scored: 1 = normal, 2 = nonprotruding intimal thickening (> 2 mm), 3 = atheroma less than 4 mm +/- Ca++, 4 = atheroma greater than or equal to 4 mm +/- Ca++, and 5 = any size mobile or ulcerated lesion +/- Ca++. The ascending aorta between the aortic valve and innominate artery was divided into proximal, middle, and distal segments. A total of 66 segments were evaluated.
Although the overall agreement of scores between procedures was 75.8%, significantly more lesions were identified by EAU (15) than by TEE (5) (p < 0.03). TEE failed to identify lesions in the middle and distal segments of the aorta with a score of more than 3.
Although atheromatous lesions were identified in the ascending aorta by both ultrasound modalities, the results suggest that intraoperative EAU may have an advantage over TEE for surgeons assessing target sites for surgical procedures involving the ascending aorta.
To compare the incidence of neuropsychologic deficits 1 week and 6 months after coronary artery bypass graft (CABG) surgery (extracardiac) and valve surgery with or without CABG surgery (intracardiac) using reliable change indices to define the incidence of neuropsychologic deficits.
Prospective study.
Cardiac surgical unit in a university teaching hospital.
Patients scheduled for elective multiple-graft (> or =3 grafts) CABG surgery (n = 59), or elective valve surgery (with or without concomitant CABG surgery) (n = 50) and a matched sample of nonsurgical controls (n = 53).
Neuropsychologic assessments were performed 1 day before surgery, 7 days and 6 months after surgery.
The 7-day assessment showed no significant differences between valve surgery patients and CABG surgery patients in the incidence of neuropsychologic deficits. When reassessed 6 months postoperatively, the valve group displayed a significantly higher incidence of deficits on the digit symbol test compared with the CABG group (valve 26.7% v CABG 6.8%). In the CABG group, there was a significant change in the incidence of deficits per patient from 7 days to 6 months (p = 0.03) that was not evident in the valve group.
There are some differences in the neuropsychologic outcome of extracardiac and intracardiac surgery. Patients undergoing isolated CABG surgery showed a greater reduction in the incidence of persisting deficits at 6 months than patients undergoing valve surgery with or without CABG surgery. This finding warrants further investigation, with particular attention to patients undergoing combined valve and coronary artery procedures.
Neuropsychologic impairment is a common complication of coronary bypass surgery. Cerebral microemboli during cardiopulmonary bypass are the principal cause of cognitive deficits after coronary bypass grafting. We have previously demonstrated that the majority of cerebral emboli occur during perfusionist interventions (ie, during the injection of air into the venous side of the cardiopulmonary bypass circuit). The purpose of this study was to determine whether an increase in perfusionist interventions is associated with an increased risk of postoperative cognitive impairment.
Patients undergoing elective coronary artery bypass grafting (n = 83) underwent a battery of neuropsychologic tests preoperatively and 3 months postoperatively. Patients were divided into 2 groups according to the median value of perfusionist interventions during cardiopulmonary bypass. Group 1 patients (n = 42) had fewer than 10 perfusionist interventions, and group 2 patients (n = 41) had 10 or more interventions.
The 2 groups of patients were similar for all preoperative, intraoperative, and postoperative variables, with the exception of longer cardiopulmonary bypass times in group 2 patients (P <.001). Group 2 patients had lower mean scores on 9 of 10 neuropsychologic tests, with 3 (Rey Auditory Verbal Learning, Digit Span, and Visual Span) being statistically significant. Group 2 patients had worse cognitive test scores, even when controlling for increased bypass times. Group 2 patients had a nonsignificant trend toward an increased prevalence of neuropsychologic impairment 3 months postoperatively.
Introduction of air into the cardiopulmonary bypass circuit by perfusionists, resulting in cerebral microembolization, may contribute to postoperative cognitive impairment.
To determine the repeatability of a computerized cognitive test designed to monitor recovery from concussion and assist team physicians make return to play decisions (CogSport). To determine the correlation between CogSport and two conventional neuropsychological tests.
Prospective, serial investigation of cognitive function.
Professional and semi-professional Australian Football clubs and a university affiliated research institute in Melbourne, Australia.
Three-hundred healthy young adults, including 240 elite athletes.
Intra-class correlation (ICC) coefficients for CogSport performance measures administered serially. ICC between CogSport performance measures and conventional neuropsychological tests. Normative data for CogSport performance measures.
Measures of psychomotor function, decision making, working memory and learning were highly reliable. Some measures also displayed high correlations with conventional neuropsychological tests of information processing and attention. Preliminary normative data is described.
CogSport is a highly reliable cognitive function test when administered to healthy young adults and elite athletes. CogSport measures similar cognitive functions as conventional tests used commonly in concussion research.
Removal of intracardiac air during valvular surgery should be accomplished in the most effective manner. We conducted a prospective randomized controlled trial to compare mechanical de-airing and carbon dioxide (CO2) field flooding in 18 patients undergoing elective valvular surgery. Transoesophageal echocardiography was used to record intracardiac bubbles, and this was assessed postoperatively by two independent echocardiographers blinded to treatment group. Both assessors graded the bubble count higher in the mechanical deairing group compared with the CO2 flooding group, and there was good agreement between assessors. CO2 field flooding is more effective than mechanical de-airing in removing intracardiac bubbles following valvular surgery.
To compare recently described insufflation devices for efficient carbon dioxide (CO(2)) deairing of the cardiothoracic wound and to determine the importance of their position.
Experimental and clinical.
A cardiothoracic operating room at a university hospital.
A full-size torso with a cardiothoracic wound and 10 patients undergoing cardiac surgery.
Insufflation of CO(2) into the wound cavity at 2.5, 5, 7.5, and 10 L/min with a multiperforated catheter and a 2.5-mm tube with either a gauze sponge or a gas-diffuser of polyurethane foam at its end. The devices were tested when positioned at the level of the wound opening and 5 cm below and after exposure to fluid.
Deairing was assessed by measuring the remaining air content at the right atrium. With the multiperforated catheter, the gauze sponge, and the gas-diffuser, the lowest median air content in the torso was 8.4%, 2.5%, and 0.3%, respectively (p < 0.001), when positioned inside the wound cavity. When exposed to fluid, the gauze sponge and the multiperforated catheter immediately became inefficient (70% and 96% air, respectively), whereas the gas-diffuser remained efficient (0.4% air). During surgery, the gas-diffuser provided a median air content of 1.0% at 5 L/min, and 0.7% at 10 L/min.
For efficient deairing, CO(2) has to be delivered from within the wound cavity. The gas-diffuser was the most efficient device. In contrast to a gas-diffuser, a multiperforated catheter or a gauze sponge is unsuitable for CO(2) deairing because they will stop functioning when they get wet in the wound.
The risks that the presence of air microemboli implies in open-heart surgery have recently been emphasized by reports that their number is correlated with the degree of postoperative neuropsychological disorder. Therefore, we studied the effect of CO2 insufflation into the cardiothoracic wound on the incidence and behavior of microemboli in the heart and ascending aorta.
Twenty patients undergoing single-valve surgery were randomly divided into 2 groups. Ten patients were insufflated with CO2 via a gas diffuser, and 10 were not. Microemboli were ascertained by intraoperative transesophageal echocardiography (TEE) and recorded on videotape from the moment that the aortic cross-clamp was released until 20 minutes after end of cardiopulmonary bypass (CPB). The surgeon performed standard de-airing maneuvers without being aware of TEE findings. Postoperatively, a blinded assessor determined the maximal number of gas emboli during each consecutive minute in the left atrium, left ventricle, and ascending aorta. The 2 groups did not differ in the usual clinical parameters. The median number of microemboli registered during the whole study period was 161 in the CO2 group versus 723 in the control group (P<0.001). Corresponding numbers for the left atrium were 69 versus 340 (P<0.001), left ventricle 68 versus 254 (P<0.001), and ascending aorta 56 versus 185 (P<0.001). In the CO2 group, the median number of detectable microemboli after CPB fell to zero 7 minutes after CPB versus 19 minutes in the control group (P<0.001).
Insufflation of CO2 into the thoracic wound markedly decreases the incidence of microemboli.
Coronary artery bypass grafting has been associated with both early and late postoperative cognitive decline, but interpretation of previous studies has been limited by lack of appropriate control groups. We compared changes in cognitive performance from baseline to 3 years in patients undergoing coronary artery bypass grafting with those of a control group of patients with known risk factors for coronary artery disease but without surgery.
Patients undergoing coronary artery bypass grafting (n = 140) and a demographically similar nonsurgical control group with coronary artery disease (n = 92) completed baseline neuropsychological assessment and were followed up prospectively at 3, 12, and 36 months. Cognitive performance was assessed with a battery of neuropsychological tests, measuring the cognitive domains of attention, language, verbal and visual memory, visuospatial, executive function, and psychomotor and motor speed. The statistical analyses were performed in two ways: using data from all tested individuals, and using a model imputing missing observations for individuals lost to follow-up.
Both the coronary artery bypass grafting and nonsurgical control groups improved from baseline to 1 year, with additional improvement between 1 and 3 years for some cognitive tests. The coronary artery bypass grafting group had statistically significantly greater improvement than the nonsurgical controls for some subtests, and had a comparable longitudinal course for the remainder of the subtests. Both study groups had a trend toward nonsignificant decline at 3 years on some measures, but the overall differences between groups over time were not statistically significant.
Prospective longitudinal neuropsychological performance of patients with coronary artery bypass grafting did not differ from that of a comparable nonsurgical control group of patients with coronary artery disease at 1 or 3 years after baseline examination. This finding suggests that previously reported late cognitive decline after coronary artery bypass grafting may not be specific to the use of cardiopulmonary bypass, but may also occur in patients with similar risk factors for cardiovascular and cerebrovascular disease.
We hypothesized that a strategy that reduced aortic manipulation would reduce the incidence of cognitive deficits in patients undergoing coronary artery bypass grafting compared with the "traditional" approach and that neurobehavioral outcomes with the reduced aortic manipulation strategy would approach those obtained with off-pump coronary artery bypass surgery.
Consenting high-risk patients (those with older age, diabetes, or hypertension) scheduled for coronary artery bypass grafting and cardiopulmonary bypass were randomly assigned to 1 of 2 aortic management protocols: (1) a traditional approach in which distal anastomoses were accomplished while the aorta was crossclamped but in which proximal anastomoses were sewn while a partial occlusion clamp was applied to the aorta (multiple aortic clamping group) or (2) a reduced aortic manipulation approach in which the aorta was clamped a single time with a reduced-pressure clamp (single aortic clamping group) and the partial occlusion clamp was not used. A contemporaneous group of patients undergoing off-pump coronary artery bypass surgery without cardiopulmonary bypass was also enrolled. Subjects in all 3 groups underwent neurologic and neuropsychological testing before and after surgery. After randomization, patients assigned to either approach could be changed to another strategy if the attending surgeon determined that patient safety demanded this change. The study design anticipated that surgical techniques would evolve over the course of patient enrollment and anticipated that some patients would have intraoperative echocardiographic findings that would demand that the traditional approach (eg, severe aortic atherosclerosis) or the reduced manipulation protocol (eg, severe ischemia or poor left ventricular function) be abandoned. Thus, an unequal distribution of patients was expected. By surgeon decision, 20 of 84 multiple aortic clamping patients crossed over to single aortic clamping, and 3 of 85 single aortic clamping patients switched to multiple aortic clamping. Eligible patients had a battery of neuropsychological tests before surgery and at 6 months after surgery. A 20% decrement in 2 or more tests was defined as a neuropsychological deficit.
[table: see text].
A surgical strategy designed to minimize aortic manipulation can significantly reduce the incidence of cognitive deficits in coronary artery bypass grafting patients compared with traditional techniques. In this series, the results of the reduced aortic manipulation strategy were not significantly different from those in patients having off-pump coronary artery bypass surgery, thus emphasizing surgical technique as the primary cause of brain damage in coronary artery bypass grafting patients.
Air emboli released from incompletely deaired cardiac chambers may cause neurocognitive decline after open heart surgery. Carbon dioxide (CO2) field flooding is reported to reduce residual intracavital air during cardiac surgery. A protective effect of carbon dioxide insufflation on postoperative brain function remains unproven in clinical trials.
Eighty patients undergoing heart valve operations by median sternotomy were randomly assigned to either CO2 insufflation (group I, n = 39) or unprotected controls (group II, n = 41). Preoperative evaluation included neurocognitive test batteries consisting of six different tests, and objective measurements of brain function by means of P300 wave auditory-evoked potentials (peak latencies, ms). Neurocognitive testing and P300 measurements were repeated on postoperative day 5. Neurocognitive deficit (ND) was defined as a 20% decrement in two or more tests.
Preoperatively, P300 peak latencies did not differ between groups (374 +/- 75 vs 366 +/- 72 ms, not significant [n.s.]). Five days after surgery, P300 peak latencies were significantly shorter with CO2 protection as compared with the unprotected control group (group I: 390 +/- 68 ms, group II: 429 +/- 75 ms, p = 0.02). Clinical outcome was comparable as for mortality (group I: 1 patient; group II: 2 patients) and cerebrovascular events or confusional syndromes (group I: 5 patients; group II: 4 patients) or other clinical variables as intubation time or hospital stay. Neurocognitive test batteries did not reveal differences between groups.
Shorter P300 peak latencies after surgery indicate less brain damage in patients who underwent heart valve operations with CO2 flooding of the thoracic cavity. Even if these findings were not supported by clinical results or neurocognitive test batteries in our cohort, carbon dioxide field flooding has proven efficiency and should be advocated for all patients undergoing open heart surgery.
The popularity of off-pump (beating heart) coronary artery bypass grafting (CABG) was initially stimulated by numerous theoretical benefits including lower incidence of stroke and neurocognitive dysfunction. With a postoperative stroke rate of less than 1% for elective CABG, it has been very difficult to demonstrate any significant differences in this outcome between techniques. However, changes in neurocognitive function are more common in the postoperative setting and thus provide greater power for demonstrating improvement with changes in surgical technique. The aim of this meta-analysis was to assess whether there were significant differences in neurocognitive outcomes in patients after undergoing off-pump versus on-pump CABG. A database search for prospective randomised controlled trials of off-pump versus on-pump CABG in any language was conducted. Eight trials incorporating 892 patients fulfilled all the inclusion criteria for reporting of neurocognitive outcomes, and were able to be included in this meta-analysis. Sufficient data were available across the seven studies to combine results for five neurocognitive tests (Rey Auditory Verbal Learning, Grooved Pegboard, Trail A and B, and Digit Symbol). Overall there were no convincing differences in outcomes in neurocognitive testing between off-pump and on-pump CABG groups. The results of this meta-analysis show that there are no significant neurocognitive benefits when comparing off-pump versus on-pump CABG.
Statement of consensus on assessment of neurobehavioral outcomes after cardiac surgery
- Jm Murkin
- Sp Newman
- Da Stump
- Ja Blumenthal
Murkin JM, Newman SP, Stump DA, Blumenthal JA. Statement of consensus on
assessment of neurobehavioral outcomes after cardiac surgery. Ann Thorac Surg.
1995;59:1289-95.
Cognitive outcomes three years after coronary artery bypass surgery: a comparison of on-pump coronary artery bypass graft surgery and nonsurgical controls
- Oa Selnes
- Ma Grega
- Lm Borowicz
- Jr
- S Barry
- S Zeger
- Wa Baumgartner
Selnes OA, Grega MA, Borowicz LM Jr, Barry S, Zeger S, Baumgartner WA,
et al. Cognitive outcomes three years after coronary artery bypass surgery: a comparison of on-pump coronary artery bypass graft surgery and nonsurgical controls. Ann Thorac Surg. 2005;79:1201-9.
Statement of consensus on assessment of neurobehavioral outcomes after cardiac surgery
- Murkin