Kit V. Arom

Safety and efficacy of off-pump coronary artery bypass grafting

BACKGROUND We evaluated the application of the off-pump coronary artery bypass (OPCAB) procedure relative to safety and efficiency as measured by operative mortality postoperative complications and longitudinal outcome. METHODS Three hundred and fifty OPCAB patients were compared to 3,171 on-pump or conventional coronary artery bypass (CCAB) patients between January 1, 1997 and December 31, 1998. The groups were divided into three preoperative predicted risk categories: low-risk (0 to 2.59%), medium-risk (2.6 to 9.9%), and high-risk (> or =10%). Society of Thoracic Surgeons National Cardiac Surgery Database definitions and predicted risk group models were utilized to compare all preoperative, intraoperative, and postoperative variables using univariate analysis. RESULTS Overall comparison of the immediate outcome of CCAB and OPCAB shows little statistical significance in the variables analyzed. The operative mortality was 3.4% in both groups. When the immediate outcome was compared between groups (CCAB vs OPCAB), as well as individual risk groups (low, medium, and high), similar patterns of operative variables and postoperative complications were observed. The operative mortality in the low-risk group was 1.1% for CCAB and 1.4% for OPCAB; 7% for CCAB and 6% for OPCAB in the medium-risk group; and in the high-risk group 28.5% for CCAB compared to 7.7% for OPCAB group (p = 0.008). Short-term follow-up shows a trend of increased recurring angina and reinterventional procedures in the OPCAB patients. CONCLUSIONS Safety for OPCAB is assessed through retrospective data review. Longitudinal follow-up for survival, reintervention, and quality of postoperative document efficacy and patency rates, compared to on-pump procedures, is mandatory. This study documented the immediate safety of the OPCAB procedure. Preliminary findings at 1-year follow-up is an important finding in this study, but it is not conclusive at this time. Long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB.

Management of Flail Chest Without Mechanical Ventilation

The pathophysiology of flail chest is usually described only on the basis of paradoxical respiration, ignoring underlying pulmonary contusion. Two groups of comparable patients were treated either with early tracheal intubation and mechanical ventilation (Group 1), or with fluid restriction, diuretics, methylpredinisolone, albumin, vigorous pulmonary toilet, and intercostal nerve blocks, ignoring the paradox and treating only the underlying lung (Group 2). When tracheostomy and mechanical ventilation were not used the mortality rate went from 21% to O(p = 0.01), the complication rate from 100% to 20% (p = 0.005), and the average hospitalization from 31.3 to 9.3 days (p = 0.005). We conclude that most patients with flail chest do not need internal pneumatic stabilization if the underlying lung is treated appropriately and that tracheostomy and prolonged mechanical ventilation with a volume respirator, as practiced in most respiratory care centers, is usually a triumph of technique over judgment.

Ten years' experience with the St. Jude Medical valve prosthesis

Records of 1,298 consecutive patients who had received the St. Jude Medical prosthesis were reviewed (713 male and 585 female patients; mean age, 61.79 +/- 13.4 years). Early mortality was 5.7% (74 patients). Ninety-three percent complete follow-up was accomplished for the 1,224 patients who left the hospital (4,306.50 patient-years). One hundred ninety-two of these patients died, a late mortality of 16.9%. Sixty-four patients experienced thromboembolic episodes (17 major and 35 permanent). Twenty-four patients had anticoagulant-related bleeding, 4 had valve thrombosis, 7 had prosthetic valve endocarditis, 9 had paravalvular leak, and 10 underwent reoperation. There was no structural valve failure in this series. Twenty-two of the 118 patients who had valve-related complications died; another 15 patients died of sudden and unknown causes. Therefore, the total number of valve-related deaths was 37. Of those patients who survived, New York Heart Association functional class improved significantly (98% in classes II and III preoperatively and 96% in classes I and II postoperatively). Linearized rates for thromboembolism, valve thrombosis, and anticoagulant-related bleeding were 1.49% +/- 0.19%, 0.09% +/- 0.05%, and 0.56% +/- 0.11%/100 patient-years, respectively. The actuarial estimate of incidence free from all complications, operative death, and valve-related death was 66.9% +/- 8.2% at the end of 9 years. In spite of old age and advanced heart disease, the patients who received the St. Jude Medical prosthesis had very good results over a 10-year period.

Does multivessel, off-pump coronary artery bypass reduce postoperative morbidity?

BACKGROUND Off-pump coronary artery bypass (OPCAB) is an emerging procedure. It is assumed that elimination of cardiopulmonary bypass for coronary artery bypass grafting has the potential for reducing postoperative morbidity. This review evaluates the safety and impact of multivessel OPCABG as compared to CABG. METHODS A retrospective review of 744 patients undergoing multivessel coronary artery bypass between January 1, 1997, and March 31, 1999, was done. The total population was divided into two groups: group A (n = 609 cardiopulmonary bypass) and group B (n = 135 OPCAB). This consecutive study cohort was elective status, full sternotomy with three or more distal anastomoses performed at a single institution. RESULTS The mean risk adjusted predicted mortality was 2.3% in group A and 2.7% in group B (p = NS), with the mean number of distal anastomosis being greater in group A (3.8 vs 3.5/patient, p < 0.001). Major postoperative complications were similar but were not statistically significant between groups. Postoperative blood loss and use of blood transfusions were the only significant variables (p < 0.001). CONCLUSIONS Multivessel OPCABG can be safely performed in selected patients. Elimination of cardiopulmonary bypass did not significantly reduce postoperative morbidity. Prospective randomized trials and long-term follow-up are needed to better define patient selection and the role of OPCABG.

Is low ejection fraction safe for off-pump coronary bypass operation?

BACKGROUND Does the manipulation of the heart during off-pump coronary artery bypass (OPCAB) procedure further compromise the hemodynamic stability of a patient with depressed left ventricular function compared with the conventional coronary artery bypass (CCAB) approach? Does this manipulation induce a more dramatic hypoperfused state that may contribute to an increase in the incidence of related complications or mortality? This retrospective review of data attempted to answer the above concern. METHODS Between January 1, 1998, and June 30, 1999, 177 patients with ejection fractions of 30% or less underwent full sternotomy coronary artery bypass grafting at our institution. Of these patients, 45 underwent OPCAB procedures and 132 patients underwent CCAB. Pre-, intra-, and postoperative variables as identified by The Society of Thoracic Surgeons National Cardiac Surgery Database were compared using univariate and logistical regression analysis. RESULTS Despite recognized hemodynamic derangement during cardiac displacement, these groups of OPCAB patients appeared to tolerate the procedure well. Univariate analysis of cardiac enzyme leak and blood loss was statistically significant in the OPCAB patients. Utilizing regression analysis, cardiopulmonary bypass was the only predictor for all postoperative complications. CONCLUSIONS Multivessel coronary artery bypass utilizing the OPCAB approach in patients with depressed left ventricular function of equal to or less than 30% is appropriate and applicable. Analysis of CCAB and OPCAB variables was nonsignificant except for operative and postoperative blood loss and peak cardiac enzyme leak. Attention to intraoperative detail and hemodynamic management could be credited for the success with OPCAB.

Cost-Effectiveness and Predictors of Early Extubation

BACKGROUND This study examined predictors and cost-effectiveness of early extubation after coronary artery bypass grafting. METHODS Six hundred forty-five patients admitted to intensive care units after coronary artery bypass grafting at our institutions in 1993 were reviewed. There were 455 male and 190 female patients, which included all patients in DRG 106 and DRG 107. The patients were categorized into three groups: group A (269 patients) were extubated in less than 12 hours (7.55 +/- 2.5 hours), group B (291 patients) were extubated between 12 and 24 hours (16.85 +/- 3.3 hours), and group C (376 patients) were extubated any time after 12 hours. RESULTS The reintubation rate for the entire group was less than 1%. Univariate preoperative analyses revealed small differences between groups A and B: only 6 of 25 variables were found to reach statistical significance. Stepwise logistic regression analyses were carried out in 269 patients of group A and 376 patients of group C. Older patients (log of age, p = 0.0001), female sex (p = 0.0129; odds ratio = 1.634), use of preoperative diuretics (p = 0.0010; odds ratio = 1.965) and unstable angina (p = 0.0301; odds ratio = 1.544) were noted to be clinical factors associated with late extubation (> or = 12 hours). Early extubation was accomplished in 42%; however, further analysis revealed that many patients who were intubated overnight should have been extubated sooner. CONCLUSIONS Early extubation shortened the postoperative length of stay, resulting in reduction of cost and resource utilization. The average hospital charge per patient was approximately

Affairs of the Wounded Heart: Penetrating Cardiac Woundsfrom the Division of Cardiothoracic Surgery, The University of Texas Health Science Center at San Antonio

6,000 less in the early extubation group.

Diagnosis and Management of Major Tracheobronchial Injuries

During the 10-year period ending 1 March 1978, 100 consecutive patients with penetrating cardiac wounds entered the Bexar County Hospital with some sign of life. The early and late mortality rate, 11%, declined to 8% during the last 4 years. Noncardiac injuries were responsible for six of the eleven deaths. Complications occurred in 17. The most frequently injured chambers were the right ventricle (46) and left ventricle (30). Sixty-nine patients had stab wounds and 26 had gunshot wounds. Pericardiocentesis was falsely positive or negative in 12 of 47 patients. Two distinct syndromes were apparent, hemorrhagic shock and cardiac tamponade. Patients with shock had immediate thoracotomy. Patients with suspected tamponade had a subxiphoid pericardial window, under local or light general anesthesia, for diagnosis and decompression before endotracheal intubation and sternotomy. Most wounds were repaired by direct suture. Cardiopulmonary bypass and thoracotomy before arrival in the operating room were rarely indicated.

Subxiphoid Pericardial Window in Patients with Suspected Traumatic Pericardial Tamponade

From 1968 to 1978, 14 patients were treated for major tracheal or bronchial injury. Five injuries resulted from blunt trauma and nine from penetrating injury. Of the 5 patients with injury due to blunt trauma, three had avulsions of the right main bronchus from the trachea. In 2 of them, the injury was associated with stellate tears of the distal trachea and bronchus. The simple avulsion was repaired by a primary anastomosis of the right main bronchus to the distal trachea. For the other 2 patients, treatment consisted of right pneumonectomy. The remaining 2 patients in this group had complete transection of the trachea and underwent primary repair. Of the 9 patients with a penetrating injury, 4 had lacerations of the cervical trachea which were treated with neck exploration and tracheostomy. Three patients with partial transections of the cervical or upper mediastinal trachea were treated by primary closure. The other 2 patients had gunshot wounds to the distal right lateral trachea, which were treated by right thoracotomy and primary closure. There were no deaths, and the subsequent course was generally good in all patients.

Mini-sternotomy for coronary artery bypass grafting.

The technique, indications, and results of subxiphoid pericardial window in penetrating chest wounds with suspected traumatic pericardial tamponade are reported. The classic signs of pericardial tamponade (elevated central venous pressure, muffled heart sounds, and paradoxical pulse) are unreliable in an emergency situation. Chest roentgenograms and electrocardiograms are of little diagnostic value. Pericardicentesis was either falsely positive or negative in 50% of our patients. Therefore, unexplained high central venous pressure and hypotension were considered to be pericardial tamponade until disproved by the results of a subxiphoid pericardial window. There were 4 negative and 46 positive findings of tamponade in 50 consecutive patients with suspected traumatic pericardial tamponade who underwent creation of a subxiphoid pericardial window. There were no deaths or complications from the procedures. The early use of subxiphoid pericardial window has been a major factor in reducing our mortality rate from penetrating heart wounds to 12% overall, and 8% in the past three years.