L Dernevik

Publications of L Dernevik

• Management of pneumothorax with a mini-drain in ambulatory and hospitalized patients.

  Authors: L Dernevik, D Roberts, B Hamraz, M Nordstrand-Myntevik

  Scandinavian cardiovascular journal : SCJ. 07/2003; 37(3):172-6.

  OBJECTIVE: To test the clinical performance of a miniaturized drainage system and compare the effect on pain and mobility between the new system and a standard system. One aim was to try ambulatoryOBJECTIVE: To test the clinical performance of a miniaturized drainage system and compare the effect on pain and mobility between the new system and a standard system. One aim was to try ambulatory treatment in patients with uncomplicated pneumothorax (35/55), another to see if patients with more severe diseases and pneumothorax could be mobilized better while in hospital. DESIGN: Follow-up of 55 patients treated with the new system. Detailed analysis of a subgroup of 20 of those patients compared with 17 patients treated with a standard system. RESULTS: No major complications occurred. Minor complications were haematomas and bleeding in three patients. In 12% the unit had to be replaced due to blockage by clots, obstruction of the tube, or sub-optimal performance. There were nine recurrences (16%), so patients had to have a standard drain or be referred for operation. In the subgroup of 35 patients with uncomplicated primary pneumothorax, 31 (88.5%) could be managed on an outpatient basis resulting in considerable cost reductions. Many of those patients could lead a normal life, including work during the treatment time. The new drain system was significantly less painful during activities related to sleep, hygiene, toilet visits and extraction. CONCLUSION: The function of the mini-drain was satisfactory in the majority of cases, but cases with pleural fluid should be avoided. The recurrences were more due to the severe nature of the pulmonary leak rather than to inadequacy of the drain. The side effects mostly occurred in the first patients, so there was a learning curve. The new system should be tried in all patients presenting with an uncomplicated pneumo-thorax allowing ambulatory treatment. Patients with other diseases complicated by pneumothorax could have the new system in order not to be confined to bed.The new system has no place in patients bedridden due to other severe diseases.

• [Minidrainage in pneumothorax is expensive, but still beneficial. Considerate for the patient, reducing the number of hospitalization days]

  Authors: L Dernevik, D Roberts

  Läkartidningen. 09/2000; 97(35):3726-8.

  Initial tests (ten patients) are reported of a compact device, Tru-close, for the evacuation of pneumothorax. It consists of a small-bore plastic catheter combined with a small box containing aInitial tests (ten patients) are reported of a compact device, Tru-close, for the evacuation of pneumothorax. It consists of a small-bore plastic catheter combined with a small box containing a flutter-valve. Ease of insertion, safe function, stable fixation and painless removal were features found. Complications were pain on insertion in one patient and leakage of pleural fluid from the device in another. The unit is expensive, but in cases of simple pneumothorax without fluid it would seem possible to manage patients on an out-patient basis, thus saving several days' worth of hospitalization costs.

• [Use pleural drainage optimally! Current systems are quick and easy to manage].

  Authors: L Dernevik

  Läkartidningen. 11/1999; 96(47):5227-30.

  Recent years have witnessed improvements in pleural drainage systems, especially in terms of emitted noise levels. Pleural drainage can now be performed without noise disturbance in the ward. It isRecent years have witnessed improvements in pleural drainage systems, especially in terms of emitted noise levels. Pleural drainage can now be performed without noise disturbance in the ward. It is recommended that a drainage system containing a water column manometer be used, to enable intrapleural pressure and pressure fluctuations to be monitored. Presence of increased fluctuation allows pneumothorax to be suspected, but a slight fluctuation is indicative of normal function of the drain. When active suction is terminated, the level of negative pressure obtained in the unit is preserved. Gradual dissipation of this negative pressure is indicative of a small continuing air leak from the patient, whereas preservation of the negative pressure level for several hours indicates the absence of such leakage (thus possibly obviating the need of a further x-ray before removal of chest tubes). The presence of an underwater seal is recommended, although there are systems that work without water. The systems may be used without active suction, e.g. for gravity drainage of fluid after pneumonectomy, and may temporarily function as portable Heimlich valves.

• Easy pleurectomy with winding up of pleural flaps.

  Authors: L Dernevik, G Rådberg, A Belboul

  European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery. 11/1999; 16(4):480-1.

  The authors describe an effective method of performing apical pleurectomy by winding up large pleural flaps on the thoracoscopic forceps after delineating the borders of the pleurectomy withThe authors describe an effective method of performing apical pleurectomy by winding up large pleural flaps on the thoracoscopic forceps after delineating the borders of the pleurectomy with electrocautery. The method is preferred by the authors compared to abrasio of the parietal pleura or stripping the pleura in small pieces and is in their hands easier and quicker than the other methods.

• [Epilogue to the simple and effective, but unusual method to cure hiccup]

  Authors: L Dernevik

  Läkartidningen. 09/1999; 96(34):3542.

• The significance of oral health and dental treatment for the postoperative outcome of heart valve surgery.

  Authors: M Hakeberg, L Dernevik, P Gatzinsky, C Eklöf, C Kennergren, M Jontell

  Scandinavian cardiovascular journal : SCJ. 02/1999; 33(1):5-8.

  The objective of this study was to evaluate the significance of preoperative dental treatment for the development of complications in the form of infections during the first postoperative weeks afterThe objective of this study was to evaluate the significance of preoperative dental treatment for the development of complications in the form of infections during the first postoperative weeks after heart valve surgery. In one group of patients (n = 149), oral health was examined and dental treatment performed 3-6 months prior to heart valve surgery. In a second group (n = 104), oral health was examined postoperatively and these patients did not receive any dental treatment before surgery. Infections were recorded for all patients during the first three weeks after surgery and correlated to the dental status at the time of surgery. Sepsis or endocarditis occurred in 5.4% of the first group and in 1.9% of the second group. Freedom from all infections for the two groups was 55% and 56%, respectively. The results did not reveal any significant differences between the groups regarding patients' oral health at the primary oral examination. The frequencies of postoperative complications such as focal infections, fever and increased CRP were also found to be similar for both groups. The combined scores of complications were 2.1% and 1.8%, respectively. Data from the present study do not support the suggestion that dental intervention will decrease the rate of early complications following heart valve surgery.

• Intraoperative assessement of coronary flow and coronary vascular resistance during coronary bypass surgery.

  Authors: A Belboul, G Rådberg, D Roberts, L Dernevik

  Scandinavian cardiovascular journal : SCJ. 02/1999; 33(1):23-8.

  The measurement of coronary graft flow rates is a well-established method of assessing graft function intraoperatively. In order further to understand the dynamics of graft function, the resistanceThe measurement of coronary graft flow rates is a well-established method of assessing graft function intraoperatively. In order further to understand the dynamics of graft function, the resistance to the flow was considered a desirable measurement intraoperatively. The coronary vascular resistance (CVR) was estimated by applying the Poiseuille-Hagen equation. The CVR was estimated at zero cardiac work (during cardioplegic arrest) using fixed perfusion flow rates and estimating the pressures produced. After going off cardiopulmonary bypass (CPB), the bypass graft flow (F) was estimated by a standard ultrasound Doppler technique. The perfusion pressure over the perfused coronary graft was then determined and the CVR in the working heart ascertained. The CVR was studied in 178 vein grafts in 59 patients undergoing coronary bypass surgery. The mean CVR in the cardioplegic heart (c-CVR) varied from 0.81 to 2.3 mmHg/ml/min for various coronary artery diameters and was significantly higher in small diameter arteries compared with larger arteries (p < 0.0002). Consequently significant high flows were found in the large vessels compared with the smaller ones (p < 0.0001). The mean c-CVR during cardioplegia of 1.57 +/- 0.06 increased significantly to 1.75 +/- 0.07 mmHg/ml/min after the procedure (p-CVR) and was attributed to the dynamic resistance of the working heart. The post-CPB graft flow was significantly and negatively correlated to the c-CVR of the arrested heart. The measurement of coronary vascular resistance reveals coronary beds at potential high risk for inadequate perfusion. Such areas are usually fed by small vessels with low flows. The working heart, in turn, increases the coronary resistance following cardioplegia during the surgical procedure.

• Full ventricular capture indicated by the QT interval function.

  Authors: C Gottfridsson, I Wallentin, L Dernevik, H Van Rooijen, C Van Groeningen, N Edvardsson

  Pacing and clinical electrophysiology : PACE. 12/1998; 21(11 Pt 2):2171-7.

  The atrioventricular (AV) interval is critical in dual chamber (DDD) pacing in patients with hypertrophic obstructive cardiomyopathy (HOCM) to obtain full ventricular capture (FVC) with maximalThe atrioventricular (AV) interval is critical in dual chamber (DDD) pacing in patients with hypertrophic obstructive cardiomyopathy (HOCM) to obtain full ventricular capture (FVC) with maximal reduction of the left ventricular (LV) outflow gradient and optimal LV diastolic filling. We studied the relationship of FVC, fusion, spontaneous AV conduction, and the QT interval. METHODS: 11 patients with various cardiac diseases and stable AV conduction received a QT sensing Diamond, Vitatron, DDD pacemaker. Software was downloaded into the pacemaker. In the DDD pacing mode, with the QT interval measured from the ventricular pacing stimulus to the end of the T wave, the AV interval was shortened from 400 ms, in 20-ms steps, to 90 ms. At 90 ms the stimulation rate was increased by 30 beats/min and the AV interval was increased stepwise. FVC and fusion was examined on the surface ECG. RESULTS: At 400 ms interval, spontaneous AV conduction inhibited the pacemaker. Shortening the AV interval resulted in pacing with a short QT interval. Further reduction of the AV interval resulted in a longer QT interval up to a point where the QT interval became stable. This point, the bending point in the plot of measured QT interval versus shortened AV intervals, coincided with the point of FVC. The relation of the QT-AV interval plot and the point of fusion was comparable when lengthening the AV interval at a 30 beats/min faster stimulation rate. CONCLUSION: The bending point in the QT interval versus AV interval plots showed a good correlation with the FVC and fusion points observed on ECG. The results suggest that automatic discrimination between fusion and full capture using QT interval measurements may be feasible.

• [Stimulation of the root of the tongue can cure hiccup. 20 years of "unscientific" experience supports the thesis]

  Authors: L Dernevik

  Läkartidningen. 11/1998; 95(41):4477-9.

• Half-dose aprotinin does not affect haemorheological properties in patients undergoing bypass surgery.

  Authors: B Liu, A Belboul, G Rådberg, L Dernevik, Z Liang, E Berglin, D Roberts

  Coronary artery disease. 09/1996; 7(8):609-13.

  OBJECTIVE: To investigate haemorheological changes in patients undergoing coronary artery bypass grafting and to determine whether the protective effect on haemorheology of high-dose aprotinin alsoOBJECTIVE: To investigate haemorheological changes in patients undergoing coronary artery bypass grafting and to determine whether the protective effect on haemorheology of high-dose aprotinin also exists under a half-dose regimen. METHODS: Forty patients were studied in a double-blind, placebo-controlled study design. Patients in the aprotinin group received half of the standard high dose of aprotinin during surgery. Erythrocyte and white-cell clogging rates as well as whole blood and plasma viscosity were measured. Viscosity results were expressed as a ratio to the viscosity of saline. RESULTS: Erythrocyte and white-cell clogging rates were increased significantly, whereas whole blood and plasma viscosity were decreased significantly during cardiopulmonary bypass. The reduction in viscosity had a strong correlation to haemodilution. There was no significant difference in any of the measured variables between the aprotinin and the placebo groups. CONCLUSION: This study showed that blood cell damage occurred during cardiopulmonary bypass surgery, as measured by a raised clogging rate. This tendency was the same in both groups and therefore no increased potential for microthrombi could be attributed to aprotinin haemorheologically. However, half-dose aprotinin did not show any preserving effect in haemorheology when the blood-cell clogging rate and blood viscosity were studied.

• Half-dose aprotinin preserves hemostatic function in patients undergoing bypass operations.

  Authors: B Liu, L Tengborn, G Larson, L O Rådberg, A Belboul, L Dernevik, D Roberts

  The Annals of thoracic surgery. 07/1995; 59(6):1534-40.

  High-dose aprotinin reduces bleeding in cardiac operations but with potential side-effects and increased cost. It is therefore mandatory that the effectiveness of a low dose be investigated. Half ofHigh-dose aprotinin reduces bleeding in cardiac operations but with potential side-effects and increased cost. It is therefore mandatory that the effectiveness of a low dose be investigated. Half of the Hammersmith regimen was studied in cardiac surgical patients to find out how it could reduce bleeding. Blood fibrinolysis parameters were studied in 40 elective patients undergoing coronary artery bypass grafting in a double-blind, placebo-controlled study design. The plasma activities of tissue plasminogen activator, plasminogen activator inhibitor, alpha 2-antiplasmin, plasminogen, fibrinogen, and D-dimer as well as platelet number, bleeding times, activated clotting time, and aprotinin plasma concentrations were assessed before, during, and after the operation. Fibrinolysis was inhibited by aprotinin as evidenced by decreased D-dimer (p = 0.0001) and tissue plasminogen activator (p = 0.0432) levels and increased plasminogen activator inhibitor (p = 0.0105) and alpha 2-antiplasmin (p = 0.0002) levels during the operation. A postoperative abnormal bleeding time occurred 38% more frequently in the placebo group (p < 0.05). Aprotinin plasma concentrations reached adequate levels to inhibit plasmin and plasma kallikrein. This study showed that half-dose aprotinin significantly inhibits fibrinolysis and prevents postoperative abnormal bleeding time in cardiac surgical patients.

• A comparative retrospective study of thoracoscopy versus thoracotomy for the treatment of spontaneous pneumothorax.

  Authors: G Rådberg, L Dernevik, J Svanvik, A Thune

  Surgical laparoscopy & endoscopy. 05/1995; 5(2):90-3.

  Thoracoscopic surgery has been claimed to reduce patient disability, recovery time, and hospital costs compared with open surgery. We analyzed 25 patients who had undergone thoracoscopic surgery andThoracoscopic surgery has been claimed to reduce patient disability, recovery time, and hospital costs compared with open surgery. We analyzed 25 patients who had undergone thoracoscopic surgery and compared the outcome to 24 patients who had undergone conventional surgery for spontaneous pneumothorax. The thoracoscopic group was able to return to work and daily activities earlier and had less impairment of shoulder movement. There was a loss of sensation corresponding to the dermatomes where the thoracoscopic ports were placed, which could have resulted from compression of the intercostal nerves by the instruments. However, a similar loss of sensation was found in the thoracotomy group. We conclude that thoracoscopy may be the method of choice for the treatment of spontaneous pneumothorax, although further methodological development should be done.

• Technique for prevention of gastroesophageal reflux after transthoracic Heller's operation.

  Authors: P Gatzinsky, L Dernevik, S Björk, N Sandberg

  The Journal of thoracic and cardiovascular surgery. 04/1993; 105(3):553-5.

• Effect of reduced aprotinin dosage on blood loss and use of blood products in patients undergoing cardiopulmonary bypass.

  Authors: B Liu, A Belboul, G Rådberg, L Tengborn, L Dernevik, D Roberts, G William-Olsson

  Scandinavian journal of thoracic and cardiovascular surgery. 02/1993; 27(3-4):149-55.

  High-dose aprotinin reduces bleeding after cardiac surgery, but has also evoked concern with regard to potential side effects and hospital costs. To evaluate the effects of reduced-dose aprotinin onHigh-dose aprotinin reduces bleeding after cardiac surgery, but has also evoked concern with regard to potential side effects and hospital costs. To evaluate the effects of reduced-dose aprotinin on blood loss and need for blood transfusion, 40 patients undergoing myocardial revascularization were studied (double-blind, placebo-controlled). Postoperative bleeding was reduced by 40% and erythrocyte infusion by 85% in the group given 3 x 10(6) KIU aprotinin (1 x 10(6) as a loading dose before cardiopulmonary bypass, 1 x 10(6) in the priming volume and 2.5 x 10(5)/hour intraoperatively) Aprotinin concentrations during the operation were monitored and maintained above the required level. There were no adverse effects of the drug. Hospital expenditure on blood products was reduced by 51% when aprotinin was used. Our study suggests that aprotinin in reduced dosage diminishes bleeding and requirements for blood products, and that it should be given before, during and after cardiopulmonary bypass.

• [Superior vena cava syndrome. Surgery of thrombosis of the right atrium immediately after intravenous fluid therapy is preferable]

  Authors: L Dernevik, E Houltz, C Lamm, I Wallentin

  Läkartidningen. 04/1992; 89(13):1083-4.

• High-dose aprotinin (trasylol) in reducing bleeding and protecting lung function in potential bleeders undergoing cardiopulmonary bypass.

  Authors: B Liu, A Belboul, N al-Khaja, L Dernevik, D Raberts, G William-Olsson

  Chinese medical journal. 01/1992; 104(12):980-5.

  Intraoperative high-dose aprotinin during cardiopulmonary bypass was used to investigate if high-risk bleeders could be changed to bleed normally or less as well as see if aprotinin could preserveIntraoperative high-dose aprotinin during cardiopulmonary bypass was used to investigate if high-risk bleeders could be changed to bleed normally or less as well as see if aprotinin could preserve lung function. Eleven matched controls were compared with eleven aprotinin patients taking warfarin or aspirin preoperatively. The mean (+/- SEM) 12-h and 24-h postoperative amount of bleeding, volume of blood product transfusion and hemoglobin reduction in the aprotinin group were 328 +/- 45 ml, 418 +/- 63 ml, 341 +/- 99 ml and 1.8 +/- 0.5 g% respectively, which were significantly lower than the respective values of 716 +/- 86 ml (P less than 0.01), 1,029 +/- 115 ml (P less than 0.01), 985 +/- 294 ml (P less than 0.05) and 4.1 +/- 0.4 g% (P less than 0.02) in the controls. There was a 65% blood-saving effect by aprotinin in this study. The hypercapnea rate was 45% in the treated patients, and 82% (P less than 0.05) in the controls reflecting better preservation of pulmonary diffusion function which is clinically important following major surgery.

• [Pulmonary hydatidosis--an unusual cause of recurrent hemoptysis]

  Authors: T Sandberg, L Dernevik, P Gatzinsky, I Ljungström, P Brandström

  Läkartidningen. 10/1991; 88(37):2989-92.

• Management of dumbbell tumours. Reports of seven cases.

  Authors: L Dernevik, S Larsson

  Scandinavian journal of thoracic and cardiovascular surgery. 02/1990; 24(1):47-51.

  Seven dumbbell tumours were histologically diagnosed as neurilemmoma (4), echinococcus cyst (1), chondrosarcoma (1) or neuroblastoma (1). Radical removal was achieved by thoracotomy and enlargementSeven dumbbell tumours were histologically diagnosed as neurilemmoma (4), echinococcus cyst (1), chondrosarcoma (1) or neuroblastoma (1). Radical removal was achieved by thoracotomy and enlargement of the intervertebral foramen in two cases. Thoracotomy and laminectomy were performed on separate occasions in three cases. One patient, in whom the extent of the pathologic process was known preoperatively, underwent concomitant 'minithoracotomy' and laminectomy. Postoperative bleeding required reoperation in one case. The patient with chrondrosarcoma died of local recurrence 16 months postoperatively, and the patient with neuroblastoma died of metastatic spread after 6 years. The five survivors are well. Preoperative recognition of intraspinal extension should be obtainable if a high index of suspicion is maintained in cases of paravertebral tumour. Computed tomography is the diagnostic method of choice. Single-stage removal of the intrathoracic and intraspinal portions of the tumour is desirable. The recommended procedure is posterior minithoracotomy with rib resections for exposure and possibly also laminectomy, with the patient in prone position.

• [Drainage in pneumothorax]

  Authors: L Dernevik, P Gatzinsky

  Läkartidningen. 03/1989; 86(5):332-6.

• Shrinking pleuritis with atelectasis.

  Authors: L Dernevik

  American journal of industrial medicine. 02/1989; 16(4):451-4.