Biomedical subjects

Wilfried Wisser

Publications and source records attributed to Wilfried Wisser.

15 recordsLinked to original sources

PubMed2007

Institutional experience with extracorporeal membrane oxygenation in lung transplantation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is currently accepted in lung transplantation either to bridge patients to transplantation or to treat postoperatively arising severe primary graft failure. Based on promising initial experiences we have since 2001 implemented ECMO as the standard of intraoperative extracorporeal support in lung transplantation (LuTX) patients with haemodynamic or respiratory instability with the potential to prolong ECMO support into the perioperative period. The aim of this paper is to summarise our total experience with the use of ECMO in LuTX. METHODS: We retrospectively reviewed all 306 patients undergoing primary lung transplantation from 1/2001 to 1/2006 with regard to the different forms of ECMO use. Results of all patients requiring ECMO were compared to those without ECMO during the observation period. RESULTS: ECMO was used in 147 patients in total. Two patients were bridged to transplantation. A total of 130 patients received intraoperative ECMO support. In 51 of these patients ECMO was prolonged into the perioperative period. Five of these patients required ECMO support again in the postoperative period due to graft dysfunction. Contrary cardiopulmonary bypass was used in 27 patients mainly with concomitant cardiac defects. Eleven of these patients needed therapeutic ECMO in the further course. A total of 149 patients without relevant risk factors were transplanted without any intraoperative extracorporeal support. Six of these patients required ECMO support in the postoperative period for treatment of primary graft dysfunction. Overall 3-month, 1-year and 3-year survival rates were 88.6%, 82.1% and 74.63%. The mentioned survival rates were 85.4%, 74.2% and 67.6% in the intraoperative+/-prolonged ECMO group; 93.5%, 91.9% and 86.5% in the no support group and 74.0%, 65.9% and 57.7% in the CPB group. CONCLUSION: ECMO is a valuable tool in lung transplantation providing the potential to bridge patients to transplantation, to replace CPB with at least equal results and to overcome severe postoperative complications. Favourable survival rates can be achieved despite the fact that ECMO is used in the more complex patient population undergoing lung transplantation as well as to overcome already established severe complications.

Adult↗

PubMed2005

Donor total lung capacity predicts recipient total lung capacity after size-reduced lung transplantation.

BACKGROUND: Size-reduced lung transplantation has only recently undergone widespread use, especially in highly urgent cases. However, it is still not considered standard procedure at most centers. It has the potential to alleviate the donor organ shortage by allowing the use of oversized grafts for small and pediatric recipients. Limited data exist on pre-operative parameters predicting functional outcome after lung transplantation in general, especially after size-reduced lung transplantation. METHODS: All 98 patients undergoing primary lung transplantation during a 2-year period, including 27 size-reduced lung transplantations, were analyzed retrospectively. Pre-operative functional parameters were-after correction of estimated values according to the amount of size reduction-correlated with post-operative functional assessment. Actual and predicted total lung capacity (TLC) of transplant recipients and predicted TLC of donors was compared with the best post-operative TLC achieved within 12 months after transplantation. RESULTS: Size-reduced lung transplantation was performed in 27 cases. Downsizing was achieved by lobar transplantation (n = 9), split-lung transplantation (n = 2) or peripheral segmental resection (n = 16). There was a statistically highly significant (p < 0.01) correlation between donor TLC and best recipient TLC achieved after transplantation (Pearson's correlation coefficient = 0.675). No statistically significant correlation was seen between pre-operative recipient actual TLC and best post-operative TLC (p = 0.87; Pearson's correlation coefficient = 0.415). In standard lung transplant recipients post-operative TLC was correlated with both donor predicted TLC (p < 0.01; Pearson's correlation coefficient = 0.509) and actual pre-operative recipient TLC (p < 0.01; Pearson's correlation coefficient = 0.667). CONCLUSIONS: Post-operative recipient TLC in size-reduced lung transplantation can be predicted by donor TLC rather than pre-operative recipient TLC.

Adolescent↗

PubMed2005

Extended donor criteria for lung transplantation--a clinical reality.

OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage.

Adult↗

PubMed2005

In vivo measurement of levofloxacin penetration into lung tissue after cardiac surgery.

Nosocomial pneumonia is a severe complication after cardiac surgery (CS). Levofloxacin, a fluoroquinolone, qualifies for the therapy of postoperative pneumonia. However, penetration properties of levofloxacin into the lung tissue could be substantially affected by CS: atelectasis, low cardiac output after CS, high volume loads, and inflammatory capillary leak potentially influence drug distribution. The aim of our study was to gain information on interstitial antibiotic concentrations in lung tissue in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. Therefore, six patients undergoing elective CS participated in this prospective study. A dose of 500 mg of levofloxacin was administered intravenously in addition to standard antibiotic prophylaxis immediately after the end of surgery. Time versus concentration profiles of levofloxacin in the interstitial lung tissue and plasma were determined. A microdialysis technique was used for lung interstitial concentration measurements. The microdialysis procedure was well tolerated in all patients and no adverse events were observed. The median area under the concentration curve (AUC) of levofloxacin in interstitial lung fluid was 18.6 microg.h/ml (range, 10.1 to 33.6). The median AUC for tissue (AUC(tissue)) of unbound levofloxacin/AUC(total) in plasma was 0.6 (range, 0.4 to 0.9). The median unbound AUC(tissue)/MIC was 2.4 (range, 1.3 to 4.2) for Pseudomonas aeruginosa. Our study demonstrated the feasibility and safety of microdialysis in human lung tissue in vivo after CS. The unbound AUC/MIC ratio revealed that levofloxacin used in the described manner was borderline sufficient for the treatment of nosocomial pneumonia caused by Klebsiella pneumoniae and insufficient for the treatment of pneumonia caused by Pseudomonas aeruginosa, because the breakpoint of 30 to 40 for AUC/MIC could not be reached by the conventionally used dosage schema in our post-CS setting. Penetration was lower than in previous reports.

Aged↗

PubMed2005

Total endoscopic CABG using robotics on beating heart.

BACKGROUND: The implementation of a total endoscopic coronary surgery on the beating heart with the aid of the Da Vinci surgical system (Intuitive, Sunnyvale, CA) requires a stepwise learning process. After cadaveric training and clinical start of the program in November 2002, we gained experience with arrested heart procedures starting in May 2003. In November 2003, we moved to beating heart surgery. METHODS: From November 2003 to January 2005, 14 patients with coronary artery disease (mean age of 62 +/- 5 years, female to male ratio 2:12) were operated with the intention to perform a beating heart TECAB (totally endoscopic coronary artery bypass grafting) procedure. RESULTS: Total conversion rate was 35% (5/14), due to pleural adhesions in 2 patients, injury of the lung during port placement, inability to occlude the LAD with saddle loops, atherosclerotic diseased mammary artery in 1 patient each. Mean operating time was 298 +/- 110 minutes with a steady decline throughout the study period (first 5 patients: 342 +/- 61 minutes, patients 6 to 9: 337 +/- 87 minutes, last 4 patients: 290 +/- 53 minutes), resulting in a 60 minute shorter operating time. Mean ICU stay was 1.3 days and hospital stay lasted on average 8.4 +/- 2.8 days. CONCLUSION: Total endoscopic bypass surgery on the beating heart with the Da Vinci surgical system can be safely implemented in clinical use. The learning curve results in a constantly decreasing procedure time due to a more effective table team-console surgeon-robotic system interaction and a moderate conversion rate.

Coronary Artery Bypass, Off-Pump↗

PubMed2004

Cystic fibrosis and lung transplantation--determination of the survival benefit.

INTRODUCTION: Cystic fibrosis is a well acknowledged indication for lung transplantation; however, the optimal timing for transplantation remains debatable. Liou et al. described a score for calculating 5-year probability of survival for patients with cystic fibrosis and concluded that only patients with a probability of survival < 30% gained a survival benefit from transplantation; those between 30% and 50% had equivocal survival effects from transplantation and those > 50% suffered negative effects. The aim of the present study was to determine the validity and applicability of this model. METHODS: Data from patients with cystic fibrosis transplanted between January 1995 and July 2001 were retrospectively reviewed. Survival score according to Liou was calculated from data collected before transplantation. Patients were classified according to 5-year probability of survival (group 1: < 30%, group 2: 30%-50%, groups 3-5: > 50%). Actuarial survival rates were calculated separately for each group and compared with the predicted probability of survival. RESULTS: During the observation period 27 patients were transplanted for cystic fibrosis. Three patients had to be excluded from further analysis because of incomplete pretransplant data. Fifteen patients were classified as group 1 and nine patients as group 2. No patients were eligible for groups 3 to 5. There were nine female patients and six males in group 1, mean age 22.1 +/- 4.9 years. Mean survival time was 918 +/- 787 days; 1-, 3- and 5-year survival rates were 66.6%. Three male patients and six females were classified as group 2, mean age 26.2 +/- 12.2 years. Mean survival time for this group was 701 +/- 617 days, and 1-, 3- and 5-year survival rates were 66.6%. CONCLUSION: We found that only patients with a 5-year probability of survival < 50% had been transplanted. For patients in groups 1 and 2 we report identical 5-year survival rates of 66.6%. According to our experience, cystic fibrosis patients with a 5-year probability of survival < 30% and also those between 30% and 50% gain a clear survival benefit from bilateral lung transplantation.

Actuarial Analysis↗

PubMed2004

Triangular plication of the anterior mitral leaflet: a new operative technique.

This study describes the technique of triangular plication in patients with mitral valve incompetence that is due to segmental anterior leaflet prolapse. A nonabsorbable suture plicates the prolapsed leaflet area towards the ventricular aspect in a triangular fashion by decreasing the suture width towards the leaflet base. Because no leaflet tissue is resected, this technique allows for the intraoperative correction of an imperfect plication. Triangular plication was successful in all except one patient. In this patient, a failed repair was corrected with mitral valve replacement. Freedom from mitral valve incompetence of more than grade 0-I was 100% at 12 months and 86% at 36 months postoperatively.

Chordae Tendineae↗

PubMed2004

Lobar transplantation, split lung transplantation and peripheral segmental resection--reliable procedures for downsizing donor lungs.

OBJECTIVES: The increasing scarcity of donor lungs, especially for small and pediatric recipients has stimulated the development of new operative techniques, which allow larger lungs to be downsized for use in smaller recipients. This approach has only recently gained widespread use-especially for highly urgent recipients-however, it is still not considered a standard procedure. METHODS: This report reviews the Vienna University experience with cadaveric split lung transplantation, lobar transplantation and by means of peripheral resection size reduced lung transplantation within the years 2001-2002. Peri-operative complications and outcome of those patients were retrospectively analysed and compared to the patients undergoing standard single or double lung transplantation during the observation period. RESULTS: During the observation period 98 primary lung transplantations were performed, of which 27 (27.6%) were size reduced transplantations. Size reduction was achieved by lobar transplantation (n=9), split lung transplantation (n=2) or peripheral segmental resection (n=16). There was no statistically significant difference between the size reduced and standard lung transplantation group with regard to the rate of bronchial healing problems (n=3/7; P=0.85) and the rate of post-operative bleeding (n=5/12; P=0.85). No other major thoracic surgical complications were observed. Three months survival rate was 85.2% in the size reduced group, compared to 92.9% in the standard group (P=0.13). CONCLUSIONS: Size reduced lung transplantation, including split lung transplantation, lobar transplantation and peripheral segmental resection, is a reliable procedure providing equal results compared to standard lung transplantation.

Adolescent↗

PubMed2004

Microwave and radiofrequency ablation yield similar success rates for treatment of chronic atrial fibrillation.

OBJECTIVE: To evaluate the influence of two different ablation devices (microwave AFx and radiofrequency Medtronic), designed to create linear lesion lines, with respect to efficacy and restoration of sinus rhythm (SR). METHODS: Between February 2001 and December 2002, 42 patients with chronic, persistent atrial fibrillation (AF) >6 months were submitted to different combinations of valve surgery (mitral+/-tricuspid, n = 30; mitral and aortic+/-tricuspid reconstruction, n = 6 aortic+/-tricuspid, n = 8) and concomitant Maze procedure. The biatrial Maze followed the concept of the Cox III procedure, using either microwave energy (AFx Lynx) (group I: age 65.8+/-11.9 years, mean duration of AF 61.9+/-28.9 months, n = 23) or radiofrequency (Medtronic Cardioblate) (group II: age 64.1+/-11.1 years, mean duration of AF 53.5+/-49 months, n = 19). RESULTS: There was one death with group I (4%), due to liver failure. Both groups were comparable with regard to Euro Score, ejection fraction, cross clamp time, cardiopulmonary bypass time, ICU (median 1 day in both groups) and hospital stay, and type of indication. The preoperative diameter of the left atrium was 69.7+/-10.8 and 74.0+/-14.3 mm in groups I and II, respectively (P = 0.359). The Maze procedure resulted in 23+/-2 and 17+/-1 min additional cross clamp time in groups I and II, respectively (P = 0.013). At the 12-month follow up, freedom from AF was 81 and 80% in groups I and II, respectively. Twenty percent in group I and 21% in group II needed a pacemaker (PM), due to sick sinus syndrome (2 versus 2 cases), AV bloc (2 versus 1 case) and preoperative bradycardia (0 versus 1 case), respectively. CONCLUSIONS: The combination of complex valve surgery and Maze procedure was safe and reproducible. Following the Cox Maze III line concept, microwave and radiofrequency ablation gave similar results even in patients with more complex double or triple valve procedures.

Adult↗

PubMed2004

Heterotopic tracheal transplantation with omentum wrapping in the abdominal position preserves functional and structural integrity of a human tracheal allograft.

OBJECTIVES: Transplantation of a human trachea has been reported only twice in the literature with limited documentation of the functional and structural properties of the allograft. PATIENTS AND METHODS: A 57-year-old patient with chronic obstructive pulmonary disease with low segment tracheal stenosis was accepted for lung transplantation and 2-stage tracheal allotransplantation. Standard bilateral sequential lung transplantation was performed with the transfer of the donor trachea into the recipient's abdomen, which was wrapped in the greater omentum and sutured into the abdominal wall, similar to a stoma. The patient received immunosuppression consisting of cyclosporine A, mycophenolate mofetil, and cortisone. Sixty days later, the tracheal allograft presented with macroscopically normal appearance with maintained elasticity and rigidity. The patient underwent a cricotracheal resection 6 months after lung transplantation. However, reconstruction with direct end-to-end anastomosis was achievable. The tracheal allograft, therefore not needed for reconstruction, was harvested and underwent complete investigations. RESULTS: Cross-section of the graft revealed a mechanically stable and macroscopically intact trachea. Hematoxylin-eosin staining demonstrated vital cartilage covered by respiratory epithelium. Angiography, followed by corrosion studies and electromicroscopy, demonstrated excellent vascularization of the tracheal wall. CONCLUSION: The patient is alive 31 months posttransplantation and remains in bronchiolitis obliterans syndrome stage 0. Human trachea wrapped in omentum maintains its functional and structural integrity and may be used for 2-stage allotransplantation.

Abdominal Wall↗

PubMed2004

Complicated acute aortic dissection type B caused by femoral cannulation for endoscopic coronary artery bypass surgery.

PURPOSE: To report endovascular treatment of a patient with complicated acute aortic type B dissection caused by cannulation of the femoral artery for endoscopic coronary artery bypass (CAB) surgery. CASE REPORT: A 63-year-old man underwent single-vessel CAB surgery facilitated by the Da Vinci surgical system. After the procedure, acute lower limb ischemia led to the discovery of a type B dissection from the left subclavian artery to the iliac arteries. The subclavian artery was also dissected, with only minimal flow in the left mammary artery. The visceral and renal vessels originated from the false lumen and were not perfused. Emergent stent-graft placement was undertaken to close the entry tear and re-establish perfusion of the lower extremity as well as visceral and renal organs. Additional stent-grafts were placed in the dissected left subclavian artery to perfuse the left internal mammary bypass and in the inferior mesenteric artery, which arose from the false lumen. Six months after operation, the patient is well. CONCLUSIONS: Acute iatrogenic aortic dissection secondary to endoscopic CAB surgery can be treated emergently to restore distal perfusion to vital organs.

Aneurysm↗

PubMed2002

The value of switching from cyclosporine to tacrolimus in the treatment of refractory acute rejection and obliterative bronchiolitis after lung transplantation.

Standard cyclosporine-based immunosuppression is ineffective in the treatment of refractory acute rejection (RAR) and obliterative bronchiolitis (OB) that follows lung transplantation. The aim of this study was to evaluate the results of switching from cyclosporine to tacrolimus in the treatment of these situations. Nineteen patients entered the study. The indication for switching was OB in 11 patients and RAR in 8. Mean age was 41.3 +/- 13.1 years. In patients with RAR, the number of acute rejections was 1.5 +/- 0.7 and there were zero episodes per patient per 100 days before and after switching, respectively ( P = 0.02). There was no significant reduction of the decline of forced expiratory volume (FEV(1)) within 6 months after switching in patients with OB. We conclude that the conversion from cyclosporine to tacrolimus was associated with favourable results in the treatment of RAR. Further studies are required to assess the influence of this approach in the treatment of OB.

Acute Disease↗

PubMed2002

Bilateral lung transplantation with intra- and postoperatively prolonged ECMO support in patients with pulmonary hypertension.

OBJECTIVE: Lung transplantation for pulmonary hypertension (PH) is usually performed on cardiopulmonary bypass, with the disadvantage of full systemic anticoagulation, uncontrolled allograft reperfusion and aggressive ventilation. These factors can be avoided with intra- and postoperatively prolonged extracorporeal membrane oxygenator (ECMO) support. PATIENTS AND METHODS: Between February 1999 and March 2001, 17 consecutive patients with PH (systolic pulmonary artery pressure >70 mmHg) of different etiologies underwent bilateral lung transplantation (BLTX). There were 11 females and six males in the age range from 7 to 50 years (mean age, 28.4+/-12.9 years). Six patients were preoperatively hospitalized, four in the intensive care unit (ICU), one was on ECMO for 3 weeks pretransplantation, and one was resuscitated and bridged with ECMO for 1 week until transplantation. Femoral venoarterial ECMO support with heparin-coated circuits was set up after induction of anesthesia and discontinued at the end of surgery (n=3) or extended for 12 h median into the postoperative period (n=14). Postoperative ventilation pressure was kept below 25 mmHg. Allograft function at 2 h after discontinuation of ECMO, outcome and adverse events were monitored in all patients. Mean follow up time was 18+/-11.4 months. RESULTS: The perioperative mortality was 5.9% (n=1). Arterial oxygen pressure measured 2 h after weaning from ECMO, and under standard mechanical ventilation with a peak pressure of 25 mmHg and inspired oxygen fraction of 0.4, was 157+/-28 mmHg. The mean pulmonary artery pressures were reduced to 29+/-3,4 from 66+/-15 mmHg before transplantation. Postoperative complications included rethoracotomy due to bleeding (n=4) and temporary left ventricular failure (n=4). Median ICU stay was 12 days. Incidence of rejection within the first 100 days was 0.4 per patient. CONCLUSION: BLTX with intraoperative and postoperatively prolonged ECMO support provides excellent initial organ function due to optimal controlled reperfusion and non-aggressive ventilation. This results in improved outcome even in advanced forms of PH.

Adolescent↗

PubMed2002

Successful lung volume reduction surgery brings patients into better condition for later lung transplantation.

OBJECTIVES: Lung volume reduction surgery (LVRS) is accepted as a potential alternative therapy to lung transplantation (LTX) for selected patients. However, the possible impact of LVRS on a subsequent LTX has not been clearly elucidated so far. We therefore analyzed the course of 27 patients who underwent LVRS followed by LTX in our institution. METHODS: Twenty-seven patients (11 male, 16 female, mean age 51.9+/-2.2 years) out of 119 patients who underwent LVRS between 1994 and 1999 underwent LTX 29.7+/-3.2 months (range 2-57 months) after LVRS. Based on the postoperative course of FeV1 after LVRS (best value within the first 6 months postoperatively compared with the preoperative value) patients were divided into two groups: Group A (n=11) without any improvement (FeV1 <20% increase), and Group B (n=16) with FeV1 increase > or = 20% after successful LVRS which declined to preoperative values after 8-42 months. Subsequent LTX was performed 22.9+/-5.6 months after LVRS in Group A and 34.3+/-4.9 months after LVRS in Group B (P<0.05). Patients were analyzed according to the course of their functional improvement and of their body mass index (BMI) after LVRS and to survival after LTX, respectively. Values are given as the mean+/-SEM and significance was calculated by the chi(2)-test whereas continuous values were estimated by Student's t-test. RESULTS: Patients in Group A without improvement in FeV1 after LVRS had no increase in BMI as well and this resulted in a high perioperative mortality of 27.3% after LTX. On the contrary, patients in Group B, who had a clear increase of FeV1 after LVRS, experienced a significant increase of BMI of 23.2+/-4.5% as well (P<0.05). This improvement in BMI remained stable despite a later deterioration of FeV1 prior to LTX. After LTX, these patients had a significantly lower perioperative mortality of 6.3% as compared to Group A (P=0.03). CONCLUSIONS: Successful LVRS delays the need for transplantation, improves nutritional status and brings patients into a better pretransplant condition, which results in decreased perioperative mortality at LTX. Patients after failed LVRS, however, should be considered as poor candidates for later transplantation.

Body Mass Index↗

PubMed2002

Intrapulmonary shunt after cardiopulmonary bypass: the use of vital capacity maneuvers versus off-pump coronary artery bypass grafting.

OBJECTIVES: It has been proved in human subjects and animals that atelectasis is a major cause of intrapulmonary shunting and hypoxemia after cardiopulmonary bypass. Animal studies suggest that shunting can be prevented entirely by a total vital capacity maneuver performed before termination of bypass. This study aimed to test this theory in human subjects and to evaluate possible advantages of off-pump coronary artery bypass grafting. METHODS: Twenty-four patients scheduled for coronary artery bypass grafting were randomly assigned to receive no total vital capacity maneuver (control group, n = 12) or standard total vital capacity maneuvers (TVCM group, n = 12). Additionally, 12 consecutive patients undergoing off-pump coronary artery bypass grafting (off-pump group) were studied. Systemic and central hemodynamics, the pattern of breathing, and ventilatory mechanics were evaluated after induction of anesthesia, after sternotomy, after cardiopulmonary bypass and skin closure, and 4 hours after extubation. RESULTS: The use of total vital capacity maneuvers reduced (P <.05) intrapulmonary shunting after termination of cardiopulmonary bypass. However, shunting increased (P <.05) in all groups (control group, 8.2% +/- 3.3% vs 25.6% +/- 8.1%; TVCM group, 8.7% +/- 3.4% vs 24.4% +/- 8.5%; and off-pump group, 7.8% +/- 2.8% vs 14.0% +/- 5.3%) after extubation, but the increase was significantly (P <.05) less pronounced in the off-pump group. Furthermore, pulmonary compliance decreased (P <.05) in all groups except the off-pump group after extubation. Duration of hospital and intensive care unit stay was significantly shorter (P <.05) in the off-pump group than in the other groups. CONCLUSION: The development of intrapulmonary shunting and hypoxemia after coronary artery bypass grafting can be substantially reduced by performance of total vital capacity maneuvers while patients are mechanically ventilated. However, off-pump coronary artery bypass surgery is superior in preventing shunting and hypoxemia after bypass grafting in the immediate and early postoperative periods, probably leading to substantially shorter intensive care unit and hospital stays.

Aged↗