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EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 06/2012; 8(2):185-6. · 3.29 Impact Factor
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ABSTRACT: Quadricuspid aortic valve (QAV) is rare and its diagnosis, clinical course, and management are less well defined relative to other aortic valve abnormalities. Advances in diagnostic imaging, notably in ultrasound, have increased clinical awareness of this anomaly and prompted this review of our experience with 12 new patients and a compilation of previously reported patients to further characterize this condition.
Echocardiography 08/2011; 28(9):1035-40. · 1.24 Impact Factor
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Archives of surgery (Chicago, Ill.: 1960) 08/2011; 146(8):983-4. · 4.32 Impact Factor
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ABSTRACT: Public and private organizations have called for increased transparency in reporting of outcomes data for hospitals and surgeons, including risk-adjusted coronary artery bypass graft surgery (CABG) mortality data. Limited information is available about how the public actually interprets these data.
Four different graphical and tabular displays of CABG outcomes for surgeons, three of which were modeled on current state public reports, were shown to 337 adults. Each display contained data for 3 to 5 hypothetical surgeons. For each format, respondents were asked to choose which surgeon they would be most and least likely to choose based on the data. Additionally, they were asked questions about public reporting.
Accurate identification of best surgeon performance varied by display format, with a high of 66% on one display and a low of 16% on another. Only 6.4% identified the surgeon with the lowest risk mortality across all four displays. Respondents with at least some college education were significantly more likely to identify the surgeon with the lowest risk-adjusted mortality, compared with respondents having no college education (21% to 72% vs. 9% to 59%; p<0.01). In one display, the surgeon with the lowest risk-adjusted mortality was effectively penalized for taking on higher-risk patients; respondents tended to select the surgeon with the lowest-risk population but the highest risk-adjusted mortality. Overall, 82% of respondents said that access to these types of data would be "absolutely essential" or "very important" in choosing a surgeon.
Comprehension by the public of risk-adjusted CABG outcomes is limited and varies by display format. Poorly constructed displays may have led to misinterpretation, with potential unintended adverse consequences such as risk aversion. Further work is needed to design displays that maximize accurate interpretation by the public and more clearly define the risk and benefit of public reporting of surgeon performance.
The Annals of thoracic surgery 05/2011; 91(5):1400-5; discussion 1405-6. · 3.74 Impact Factor
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ABSTRACT: This study aimed to assess the accuracy of two-dimensional echocardiography (echo) in diagnosing unicuspid aortic valve (UAV) and to determine echo features that could improve the diagnosis.
We reviewed transthoracic/transesophageal echoes (TTE/TEE) from our hospital database for adult patients who had aortic valve surgery with a preoperative echo diagnosis of UAV or equivocal diagnosis of bicuspid aortic valve (BAV) BAV/UAV. Morphological characteristics of AV and ascending aortic dimensions were evaluated.
Nineteen patients were identified, 13 (11 Male, 2 Female, mean age 47 ± 10 years) had surgically confirmed diagnosis of UAV, six had BAV. The incidence of UAV was 2.6%. For diagnosing UAV, the sensitivity and specificity of TTE was 27% and 50% and those of TEE was 75% and 86%, respectively. For TTE, positive predictive value (PPV) was 60% and negative predictive value (NPV) was 20%. By TEE, PPV was 90% and the NPV was 67%. In UAV patients, 85% had severe aortic stenosis (mean gradient 45 ± 16 mmHg, AVA: 0.9 ± 0.2 cm²). 46% had ascending aorta aneurysm (mean aortic root, sinutubular junction, ascending aorta dimensions: 36 ± 3 mm, 31 ± 4 mm and 41 ± 8 mm). Patients with ascending aortic aneurysm were younger (41 ± 11 years vs. 52 ± 5 years, P < 0.05) All UAV were unicommissural with a posteriorly positioned commissural attachment, 69% were heavily calcified. Diagnostic accuracy was limited by quality of images, severity, and distribution of calcification.
TEE is the diagnostic modality of choice in UAV. Identifying several echo features may improve its diagnostic accuracy.
Echocardiography 10/2010; 27(9):1107-12. · 1.24 Impact Factor
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ABSTRACT: Article Title: Diagnosis of Congenital Unicuspid Aortic Valve in Adult Population: The Value and Limitation of Transesophageal Echocardiography
(Echocardiography 2010;27:1106).
Echocardiography 10/2010; 27(9):1106. · 1.24 Impact Factor
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ABSTRACT: In this study, we sought to characterize the outcomes after isolated coronary artery bypass grafting (CABG) in patients with a history of remote (≥14 days), and recent (<14 days), percutaneous coronary intervention (PCI).
Patients with PCI within 5 years of CABG were identified among 12 591 primary isolated CABG reported in the mandatory Massachusetts Adult Cardiac Surgery Database. Patients were excluded if they were out-of-state (n=1043, 8%), had undergone primary PCI for acute myocardial infarction (n=401, 3%), had a PCI-CABG interval >5 years or unknown (n=136 and n=673, 1% and 5%). Patients with a history of remote and recent PCI were analyzed separately. Each CABG patient with PCI was matched to 3 patients without PCI using a propensity score. Outcomes were analyzed using generalized estimating equations and stratified proportional hazards models, with a mean follow-up of 4.1±1.2 years. There were 1117 CABG patients (9%) with prior PCI (n(remote)=823; n(recent)=294). In matched CABG patients with remote prior PCI, no differences were found in 30-day mortality (1.1% versus 1.5%; P=0.432), hospital morbidity (41% versus 40%; P=0.385) and overall survival (hazard ratio, [95% confidence interval] for death for prior PCI, 0.93 [0.74 to 1.18]; P=0.555). In matched CABG patients with recent prior PCI, hospital morbidity was higher (59% versus 45%; P<0.001), but no differences were found in 30-day mortality (3.5% versus 3.1%; P=0.754) and overall survival (HR, 1.18 [0.83 to 1.69]; P=0.353).
In patients undergoing CABG, remote prior PCI (≥14 days) was not associated with adverse outcomes at 30 days or during long-term follow-up.
Circulation Cardiovascular Interventions 10/2010; 3(5):460-7. · 6.06 Impact Factor
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ABSTRACT: In 2003, a satellite cardiac surgery program (SAT) was implemented at an affiliated community hospital located in an area historically served by an academic medical center (AMC). This study assessed the financial consequences and the changes in case-mix that occurred at the AMC after SAT implementation.
From June 2002 through December 2005, 4593 adult patients underwent cardiac operations at the AMC. Excluded were 400 patients operated on during the 4-month transition period after SAT implementation and 1210 patients living more than 35 miles from the AMC. Multivariable regression was used to compare changes in case-mix and propensity-score adjusted costs for AMC patients referred from SAT area (N(before/after =) 328/291) vs other patients (N(before/after =) 897/1467).
The SAT area referral rate decreased by 55%. Compared with other patients, AMC patients referred from the SAT area showed a greater increase in age in the second period (p = 0.013). The nursing workload and adjusted mean costs increased more for patients from the SAT area (p = 0.015 and 0.014, respectively). The hospital margin decreased in the second period for both referral areas (p < 0.001). For the patient subgroup undergoing coronary artery bypass grafting, this hospital margin decrease was greater for SAT area patients (p = 0.017).
After implementation of SAT program, fewer patients of lower complexity came to the AMC from the SAT area, and there was a significant increase in nursing workload and costs. During this interval, hospital margin for cardiac operations decreased from both referral areas but decreased significantly more for coronary artery bypass graft patients from the SAT area.
The Annals of thoracic surgery 09/2010; 90(3):805-12. · 3.74 Impact Factor
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ABSTRACT: Aortic dilation and dissection are well-recognized cardiac abnormalities in women with Turner syndrome (TS), although the underlying pathophysiology is not fully understood. We report on a 46-year-old Hispanic woman who was previously diagnosed with moyamoya disease on magnetic resonance imaging after a presentation with stroke-like symptoms. Her features were consistent with TS and chromosome analysis revealed mosaicism in which 17% of the cells showed a pseudoisodicentric Y chromosome: 45,X (25)/46,X psu idic (Y)(11.2) (5). A preceding screening transthoracic echocardiogram had shown a bicuspid aortic valve (BAV) with an aortic diameter of 3.2 cm; at the time of moyamoya diagnosis, the aorta was 3.5 cm with mild aortic stenosis and mild aortic regurgitation. Four years later, the patient had had an acute aortic dissection, Stanford type A, which was repaired successfully. This case report is the third individual with TS associated with moyamoya disease and the first associated with dissection. The small number of cases does not allow detailed analysis other than noting patient age (two older than 40 years), karyotype (two others associated with isochrome Xq), and associated cardiac risk factors (one with BAV). Although this may be a chance occurrence, we hypothesize that moyamoya disease could be a manifestation of the vasculopathy in TS.
American Journal of Medical Genetics Part A 08/2010; 152A(8):2085-9. · 2.39 Impact Factor
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ABSTRACT: Heparin-induced thrombocytopenia (HIT) is associated with a high incidence of vein graft occlusion after cardiac surgery. When HIT is suspected during the post-operative period, current guideline recommends a direct thrombin inhibitor such as argatroban to be started immediately. The aim of this retrospective study was to evaluate the safety and efficacy of argatroban in the early period after cardiac surgery. All patients who received argatroban within 72 h after cardiac surgery from September 2005 to June 2009 from a single center were included. Patient demographics, pre-operative relevant history, intra-operative events and post-operative data were collected and analyzed. The primary endpoints were bleeding, thrombotic complication during or after argatroban administration, and in-hospital mortality. The study population comprised 31 patients administered argatroban within 72 h after cardiac surgery. Argatroban was started a mean of 1.7 days after surgery (median dose, 0.66 μg/kg/min; median duration, 5.9 days). Twenty patients (64.5%) experienced bleeding; episode driven entirely by the need for blood transfusion. No new thromboembolic complication occurred during or after argatroban infusion. One patient died from aspiration pneumonia. Compared to those without bleeding complications, patients who bled had longer operation times and increased use of intra-aortic balloon pump. However, argatroban therapy including the starting time, median dose, infusion duration, and activated partial thromboplastin times showed no difference between the two groups. In cardiac surgery patients with clinical suspicion of HIT, early postoperative use of argatroban seems well-tolerated and associated with a low risk of thrombotic events.
Journal of Thrombosis and Thrombolysis 05/2010; 30(3):276-80. · 1.48 Impact Factor
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ABSTRACT: The significance and clinical role of cardiac troponin testing after coronary artery bypass grafting remain unclear.
Cardiac troponin T (cTnT) was measured during the first 24 hours after coronary artery bypass graft surgery in 847 consecutive patients. Only 17 patients (2.0%) had new Q waves or left bundle-branch block after surgery; however, cTnT elevation was observed in nearly all subjects, with a median cTnT concentration of 1.08 ng/mL overall. Direct predictors of postoperative cTnT values included preoperative myocardial infarction (P<0.001), preoperative intraaortic balloon pump (P<0.001), intraoperative/postoperative intraaortic balloon pump (P<0.001), number of distal anastomoses (P=0.005), bypass time (P<0.001), and number of intraoperative defibrillations (P=0.009), whereas glomerular filtration rate (P<0.001), off-pump coronary artery bypass grafting (P=0.003), and use of warm cardioplegia (P=0.02) were inversely associated with cTnT values. A linear association was seen between cTnT levels and length of stay and ventilator hours, and in an analysis adjusted for the Society for Thoracic Surgery Risk Model, cTnT remained independently prognostic for death (odds ratio, 3.20; P=0.003), death or heart failure (odds ratio, 2.04; P=0.008), death or need for vasopressors (odds ratio, 2.70; P<0.001), and the composite of all 3 (odds ratio, 2.57; P<0.001). In contrast to consensus-endorsed cTnT cut points for postoperative evaluation, a cTnT <1.60 ng/mL had a negative predictive value of 93% to 99% for excluding various post-coronary artery bypass graft surgery complications.
cTnT concentrations after coronary artery bypass graft surgery are nearly universally elevated, are determined by numerous factors, and are independently prognostic for impending postoperative complications when used at appropriate cut points.
Circulation 08/2009; 120(10):843-50. · 14.74 Impact Factor
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ABSTRACT: Atheroemboli caused by aortic manipulation poses a risk for stroke in patients undergoing cardiopulmonary bypass (CPB) surgery. One potential cause is the high velocity jet from aortic perfusion cannulae. This study describes the flow patterns of a novel funnel-tip cannula designed to reduce emboli by decreasing fluid velocity and resultant shear force on the aortic wall.
A funnel-tip cannula was constructed and compared with standard straight-tip cannulae and the Dispersion (Research Medical Inc, Midvale, UT) and Sarns Soft Flow (Terumo Cardiovascular Systems Corp, Ann Arbor, MI) cannulae. Pressure drop measurements were collected at 1 to 6 L/minute flows. Velocity flow profiles were created using phase contrast magnetic resonance imaging. Absolute velocity was measured in a phantom aorta at 5 L/minute flow. Each cannula was further studied in a synthetic model of an atherosclerotic aorta to determine the mass of dislodged particulate matter generated at 2, 3, and 5 L/minute flows.
The funnel-tip cannula demonstrated significantly lower values (p < 0.05) in pressure drop (55 mm Hg), exit velocity (309 cm/second, 167 cm/second for center axis and wall, respectively), and particulate dislodgement (0.15 +/- 0.05 g) than other tested cannulae. The Soft Flow cannula generated the next lowest pressure drop but exhibited twice the exit velocity and particulate dislodgement of the funnel-tip cannula. The Dispersion cannula did not demonstrate a reduction in velocity or particulate dislodgement compared with the standard straight-tip cannulae.
The results of this study suggest that a low-angled funnel-tip cannula has favorable flow characteristics warranting further investigation. Design development may reduce the risk of atheroemboli generation during CPB surgery.
The Annals of thoracic surgery 08/2009; 88(2):551-7. · 3.74 Impact Factor
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ABSTRACT: We sought to assess early and late survival and cardiovascular-specific mortality after surgical repair of acute ascending aortic dissection and the effect of differences in surgical technique, patient characteristics, and preoperative diagnostic testing.
Between 1979 and 2003, 195 consecutive patients underwent repair for acute ascending aortic dissection within 2 weeks of the onset of symptoms. Mean follow-up was 7.0 +/- 5.9 years (range, 0-26 years) and was 100% complete.
Patients were aged 62 +/- 15 years on average and were mostly male (66%) and hypertensive (69%). Risk of death early and late after the operation decreased over the study period, with hospital mortality decreasing from 21% to 4% when comparing the first and most recent quartiles (P = .007, chi(2) test for trend). At 1, 5, 10, and 20 years postoperatively, survival was 84%, 69%, 55%, and 30%, respectively, and freedom from cardiovascular death was 86%, 80%, 71%, and 51%, respectively. Additional independent risk factors for death were older age (P < .001), renal dysfunction (P < .003), syncope (P = .007), and peripheral vascular disease (P = .006). During the study period, echocardiographic and computed tomographic diagnostic imaging replaced routine aortic angiographic analysis, and operative techniques involved more frequent use of open distal anastomoses, retrograde cerebral perfusion, earlier restoration of antegrade perfusion, and a conservative approach to aortic arch repair. Freedom from reoperation on the aorta or aortic valve was 93% and 84% at 5 and 10 years, respectively.
Early and late survival after repair of acute ascending aortic dissection has improved progressively over 25 years in association with noticeable changes in preoperative and intraoperative management. Aortic reoperations were infrequent during follow-up.
The Journal of thoracic and cardiovascular surgery 05/2009; 138(6):1349-57.e1. · 3.41 Impact Factor
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ABSTRACT: Few studies of learning in the health care sector have analyzed measures of process, as opposed to outcomes. We assessed the learning curve for a new cardiac surgical center using precursor events (incidents or circumstances required for the occurrence of adverse outcomes).
Intraoperative precursor events were recorded prospectively during major adult cardiac operations, categorized by blinded adjudicators, and counted for each case (overall and according to these categories). Trends in the number of precursor events were analyzed by hospital and by defining 10 equal-sized groups across time, as were trends in outcomes obtained from institutional databases. Results from the first 101 cases performed at a new cardiac surgical site (hospital A) were compared with 2 established centers.
A steep reduction in the total number of precursor events over time was observed in the early experience of hospital A (9.2 +/- 4.9 to 2.0 +/- 1.2 events per case, from first to last decile of time, P(trend) < .0001) compared with qualitatively stable levels in the other hospitals; this reduction was driven largely by decreases in the minor severity (P(trend) < .0001), compensated (P(trend) < .0001), and environment (P(trend) < .0001) categories of precursor events. No detectable changes over time were observed in postoperative mortality and complications. No significant improvement was observed in patient comorbid conditions or medical status over time to explain the trend in hospital A.
Analyzing and targeting specific kinds of process-related failures (precursor events) may provide a novel and sensitive means of tracking, deconstructing, and optimizing organizational learning in medicine.
Surgery 02/2009; 145(2):131-7. · 3.10 Impact Factor
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ABSTRACT: Concomitant mitral regurgitation (MR) is frequently seen in patients undergoing aortic valve replacement (AVR) for aortic stenosis. This study was undertaken to characterize the magnitude of MR in these patients and identify factors associated with significant postoperative change.
Between 2002 and 2006, 391 patients with stenotic AV disease but no structural mitral valve disease underwent AVR without coronary artery bypass grafting. Excluded were 164 patients with combined aortic and mitral intervention, right heart surgery, or moderate to severe aortic insufficiency, to yield a final study group of 227 patients. Follow-up echographic evaluation of MR was obtained in 87 of 219 patients (40%) discharged alive without mitral valve intervention.
Overall mortality was 3.5%. After AVR, intraoperative MR severity improved in 66% of patients. Independent predictors of lower postoperative MR were small left atrial size (p = 0.03), the presence of aortic insufficiency (p < 0.01), and preoperative congestive heart failure (p = 0.04). Prosthetic valve type or size was not an independent predictor of postoperative MR. After adjustment for intraoperative underestimation of MR grade, there was no difference between the postprocedural MR grade and the early or late follow-up MR grade (p = 0.6 and p = 0.8, respectively).
The results of this study support a conservative, tailored approach to concomitant mitral surgery in patients presenting for correction of aortic stenosis who demonstrate functional mitral regurgitation. Characteristics associated with resolution may allow for identification of patients most likely to benefit from mitral valve repair or replacement.
The Annals of thoracic surgery 08/2008; 86(1):56-62. · 3.74 Impact Factor
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ABSTRACT: Although extensive study has been directed at the influence of patient factors and comorbidities on cardiac surgical outcomes, less attention has been focused on process. We sought to examine the relationship between intraoperative precursor events (those events that precede and are requisite for the occurrence of an adverse event) and adverse outcomes themselves.
Anonymous, prospectively collected intraoperative data was merged with database outcomes for 450 patients undergoing major adult cardiac operations. Precursor events were categorized by type, person most affected, severity, and compensation. Number and categories of precursor events were analyzed as predictors of a composite outcome combining death or near miss complications (DNM), using logistic regression.
Precursor events occurred more frequently in cases with a DNM outcome than in those with no adverse event (2.7 +/- 2.4 vs 2.0 +/- 2.3/procedure, P = .005). After adjustment for other patient characteristics, the number of precursor events remained an independent predictor of DNM (RR, 1.14 per event [1.04 to 1.24]). Of 990 events, 35.6% related to management, 28.8% were technical, and 22.8% were environment-related. The surgeon was most affected in 40.8%, and 16.5% were of major severity. When categories of precursor events were analyzed, major severity events and those most affecting the surgeon were independent predictors of DNM.
More detailed study of process in complex operations may lead to improved quality of care and patient safety. Special attention must be paid particularly to high risk patients and high risk precursor events.
Surgery 07/2007; 141(6):715-22. · 3.10 Impact Factor
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ABSTRACT: The aim of this study was to evaluate the impact of either left atrial or aortic spontaneous echocardiographic contrast (SEC), as identified on intraoperative transesophageal echocardiography, on short-term morbidity and mortality in patients with left atrial enlargement undergoing cardiac valvular surgery.
Retrospective and observational.
Single-center, university teaching hospital.
The authors identified 197 patients (105 males and 92 females; mean age, 68 +/- 14 years) with left atrial enlargement who underwent surgical intervention for valvular heart disease from January 1, 2004 to January 1, 2005.
Of the total population, 40 patients (20.3%) showed left atrial SEC, and 10 patients (5.1%) showed aortic SEC. On multivariate analysis, increasing left atrial size and the absence of mitral regurgitation were independent predictors for the presence of left atrial SEC. On multivariate analysis, the presence of atrial fibrillation and a dilated descending aorta were predictive of aortic SEC. Although the identification of left atrial SEC was an echocardiographic marker of an increased risk for thromboembolic events postoperatively, this finding did not hold true for the presence of aortic SEC.
Intraoperative identification of left atrial dilatation or aortic dilatation is predictive of SEC in the left atrium or descending aorta, respectively. The identification of left atrial SEC is an echocardiographic marker of an increased risk for thromboembolic events in this high-risk population.
Journal of Cardiothoracic and Vascular Anesthesia 01/2007; 20(6):772-6. · 1.64 Impact Factor
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ABSTRACT: Infective endocarditis is a diagnostic and therapeutic challenge that ultimately requires surgical intervention in 20% of all cases. Early determinants of morbidity and mortality in this high risk population are not well described.
The aim of this study was to determine preoperative clinical, microbiological, electrocardiographic, and echocardiographic variables that predicted the need for permanent pacemaker implantation and in-hospital death in a surgical cohort of patients with active infective endocarditis.
We identified 91 patients (61 males and 30 females, mean age 58 +/- 16 years) who underwent surgical intervention for active culture-positive infective endocarditis as defined by the Duke criteria. Native valve infective endocarditis was present in 78 (85.7%) and prosthetic valve endocarditis in 13 (14.3%) of cases. The aortic valve was infected in 61 (67.0%), the mitral in 35 (38.5%), and multiple valves in 8 patients (8.8%). The most common indication for surgical intervention was intractable heart failure. Twenty-two patients (24.2%) required pacemakers, while there were 14 (15.4%) in-hospital deaths. In age-adjusted and gender-adjusted analyses, the presence of left bundle branch block on preoperative electrocardiogram (ECG) and presence of depressed left ventricular systolic function (ejection fraction [EF] < 50%) predicted the need for a permanent pacemaker implantation, while the presence of depressed left ventricular function predicted in-hospital mortality.
Preoperative ECG findings of left bundle branch block and reduced left ventricular function may allow for early risk stratification of this high risk population.
The Annals of thoracic surgery 09/2006; 82(2):524-9. · 3.74 Impact Factor
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The Journal of thoracic and cardiovascular surgery 06/2006; 131(5):1169-70. · 3.41 Impact Factor
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ABSTRACT: Increasing attention has been afforded to the ubiquity of medical error and associated adverse events in medicine. There remains little data on the frequency and nature of precursor events in cardiac surgery, and we sought to characterize this.
Detailed, anonymous information regarding intraoperative precursor events (which may result in adverse events) was collected prospectively from six key members of the operating team during 464 major adult cardiac surgical cases at three hospitals and were analyzed with univariable statistical methods.
During 464 cardiac surgical procedures, 1627 reports of problematic precursor events were collected for an average of 3.5 and maximum of 26 per procedure. 73.3% of cases had at least one recorded event. One-third (33.3%) of events occurred prior to the first incision, and 31.2% of events occurred while on bypass. While 68.0% of events were regarded as minor in severity (e.g., delays and missing equipment), a substantial proportion (32.0%) was considered major and included anastomotic problems, pump failure, and drug errors. Most problems (90.4%) were reported as being compensated for, although many (30.9%) were never discussed among the team. Major events were more likely to be discussed (p<0.0001) and less likely to have been previously encountered (p=0.0005). Perceptions of the severity and compensation of events varied across the team, as did temporal patterns of reporting (p<0.0001).
A wide range of problematic precursor events occurs during the majority of cardiac surgery procedures. Attention to causes and ways of preventing these precursor events could have an impact on the rate of significant errors and improve the safety of cardiac surgery.
European Journal of Cardio-Thoracic Surgery 05/2006; 29(4):447-55. · 2.55 Impact Factor
