High-dose aprotinin: hemostatic effects in open heart operations

Two groups of patients were prospectively studied to evaluate the hemostatic effects of high-dose aprotinin in open heart operations. Group A patients (n = 22) received aprotinin during the entire surgical procedure. Group B patients (n = 12) served as controls. The groups were homogeneous for base variables and for cardiopulmonary bypass duration. Postoperative bleeding was lower in group A (mean, 486 mL) than in group B (830 mL) (p less than 0.01). The need for banked blood decreased by approximately half in the aprotinin patients (mean: group A, 213 mL; group B, 409 mL). Hemoglobin levels were similar in the two groups (postoperative day 7: group A, 11.29 g/100 mL; group B, 11.26 g/100 mL; NS). Platelet count decreased at the end of operation in both groups (99,000 and 95,000/mL, respectively; NS) and then increased beyond baseline levels before discharge. No complications were observed that could be attributed to aprotinin. In conclusion, we believe that the use of high-dose aprotinin is safe and effective. It decreases blood loss and reduces the need for banked blood in cardiac operations, particularly in select groups of patients (eg, those undergoing reoperation, Jehovah's Witnesses, those with renal failure).     

Antimicrobial prophylaxis for open heart operations

Between 1986 and 1988, 450 adults undergoing coronary artery bypass, cardiac valve replacement, or both were enrolled into a prospective, randomized, comparative trial of cephalothin versus cefamandole as perioperative prophylaxis. They were assessed during their hospitalization and at 6 weeks and 6 months after discharge for postoperative infectious complications. Eleven patients had major postoperative infections including 5 with sternal wound infections (three bacteremic), 6 with bacteremia, 1 with prosthetic valve endocarditis, and 3 with severe venous donor graft site infections. Eight major infections occurred in patients receiving cephalothin prophylaxis and three in patients receiving cefamandole, with all five sternal wound infections occurring in the cephalothin group. Postoperative pathogens responsible for the major infections included gram-negative aerobes in 5 patients, Staphylococcus aureus in 4, and Staphylococcus epidermidis in 2. Preoperative colonizing staphylococcal isolates were not predictive of postoperative staphylococcal pathogens. Although there was no statistically significant difference in rate of major postoperative infectious complications using either cephalothin or cefamandole prophylaxis, there was a trend in favor of cefamandole. Gram-negative aerobes are becoming increasingly important pathogens in this setting.     

Symptomatic visual deficits after open heart operations

Symptomatic visual deficits occurred in 4 patients in a series of 700 open heart operations performed by one of us (D.M.S.). The causes of these deficits were retinal emboli, occipital lobe infarction, and anterior ischemic optic neuropathy. The pathophysiology and clinical presentation of these complications are discussed, and previous reports of postoperative visual complications are reviewed.     

Cardiomyocyte apoptosis and ischemic preconditioning in open heart operations

BACKGROUND: The aim of the present study was to ascertain the percentage of left apical myocardial apoptosis in three-vessel coronary artery bypass grafting patients quantitatively and the impact of ischemic preconditioning. METHODS: Twenty-one patients with three-vessel disease who had elective coronary artery bypass grafting were randomized in a ratio of 2:1 to ischemic preconditioning (n = 14) or a control group (n = 7). The ischemic preconditioning protocol was established by two cycles of ascending aorta occlusion for 2 minutes followed by 3 minutes of reperfusion. Myocardial samples from the apex of the left ventricle were taken using a Tru-Cut needle before aortic cross-clamping and immediately after declamping. The percentage of apoptosis was analyzed by TUNEL methods. Data on hemodynamics and biochemical markers were collected. RESULTS: Low levels of myocardial apoptosis were found before the operation (0.01% +/- 0.00%). During the early reperfusion period, the percentage of myocardial apoptotic cells significantly increased (0.15% +/- 0.05%, p = 0.008). Ischemic preconditioning significantly improved cardiac index and right ventricular ejection fraction recovery after the operation (p = 0.036 and 0.001 respectively, repeated measure) but had no effect on myocardial apoptosis before and after the operation (0.01 +/- 0.00 versus 0.01 +/- 0.00, p = 0.658 and 0.12% +/- 0.04% versus 0.23% +/- 0.14%, p = 0.302). CONCLUSIONS: Cardioplegic myocardial ischemia during open heart operation was associated with induction of cardiomyocyte apoptosis in humans. Attenuation of postoperative cardiac dysfunction by ischemic preconditioning appeared to be independent of apoptosis.     

Transthoracic intra-aortic balloon pump in open heart operations: techniques and outcome

OBJECTIVE: During open heart surgery, direct transthoracic insertion of the intra-aortic balloon pump (IABP) is an alternative to the routine transfemoral insertion especially in the presence of severe peripheral vascular disease. METHODS: Over 19 years (1980-1998), 646 patients were treated with IABP. In 24 of them, the balloon was inserted transthoracic (TIABP) due to failure of transfemoral insertion in 13 or extensive occlusive aorto-iliac disease in 11 cases. RESULTS: Early mortality was 58.3% in patients having TIABP compared to 46.1% in patients with transfemoral IABP insertion (p > 0.2). Of the 24 patients receiving IABP transthoracic, none suffered vascular injury (i.e. perforation or dissection). Complications which could be related to TIABP occurred in 10 patients: 3 balloon ruptures, 1 mediastinal haemorrhage, 3 cerebrovascular accidents, 1 post-operative mediastinitis, and 2 late graft infections. CONCLUSIONS: TIABP is a useful alternative when transfemoral insertion of IABP is not feasible or hazardous because of occluded or severely diseased ilio-femoral arteries. Being a second choice and a more invasive treatment, transthoracic IABP is associated with increased mortality.     

Influence of allopurinol on cardiac complications in open heart operations

During cardiac operations, the heart is subjected to total ischemia and reperfusion, causing serious operative and postoperative complications such as arrhythmias, heart failure, and infarctions that may be partly due to free radical generation. Thus, allopurinol was tested to see if it could reduce cardiac complications during open heart operations. Ninety patients undergoing elective coronary artery bypass grafting were studied prospectively. Fortyfive patients were treated with allopurinol and 45 patients acted as controls. Treatment requiring arrhythmias in the allopurinol group was 6.6% compared with 33.3% in the control group (p less than 0.01). The percentage of patients requiring inotropes was significantly lower in the allopurinol group than in the control group (4.4% versus 26.6%; p less than 0.01). Perioperative myocardial infarction did not occur in the allopurinol group but was seen in 8 patients (17.7%) in the control group. Intraaortic balloon pumping was used in 5 control patients (11.1%) but not in the allopurinol group. This study shows that allopurinol decreases significantly the incidence of cardiac complications in open heart operations.     

New outlook on pericardial substitution after open heart operations

The difficulties of reoperation owing to adhesions are well known. Clinical attempts to solve this problem using synthetic materials or glutaraldehyde-fixed pericardial xenograft have been less than satisfactory. Although experimental animal results have been good, they have not considered the influence of cardiopulmonary bypass (CPB) on adhesion formation. This study addressed the influence of CPB on the formation of adhesions and evaluated biodegradable polyglycolic acid as a material to reduce adhesions and as a pericardial substitute. Forty-five weanling sheep received implants of pericardial xenograft and polyglycolic acid with and without CPB. The pericardial xenograft showed no adhesions when implanted without CPB, but severe adhesions formed and a thick fibrinous layer covered the heart when CPB was used, making identification of coronary arteries at reoperation very difficult. The polyglycolic acid mesh implanted without CPB was absorbed and replaced with newly formed host collagen. With CPB, the polyglycolic acid was more rapidly absorbed, and a thinner layer of host collagen formed. Therefore, future animal studies must include CPB. In agreement with reported clinical results, glutaraldehyde-fixed pericardial tissue implanted with CPB resulted in severe epicardial reaction and therefore is not an ideal pericardial substitute.     

Pediatric open heart operations without diagnostic cardiac catheterization.

BACKGROUND: Echocardiography allows for an adequate noninvasive preoperative evaluation in an increasing proportion of pediatric patients before open heart operations. The present study assessed the diagnostic accuracy of both invasive and noninvasive preoperative evaluation in children with congenital heart disease. METHODS: We prospectively evaluated the accuracy of preoperative noninvasive or invasive diagnostic methods. Preoperatively established diagnosis was compared with the intraoperative diagnosis made by surgical inspection and routine perioperative transesophageal echocardiography. RESULTS: During the study period of 30 months (ending in December 1997) 209 open-heart procedures were performed. Eighty-one patients (39%) were in the first year of life at the time of surgery, and 43% of all patients had symptoms. Noninvasive preoperative diagnosis using echocardiography was done exclusively in 142 patients (68%). Of the 67 children who had preoperative catheterization, 4 (6%) showed an additional intraoperative finding that modified the surgical approach in 2 of them. In the 142 patients who had echocardiographic preoperative assessment, the surgeons were confronted with a previously undiagnosed finding in 12 patients (8.5%). The finding was considered significant (prolongation of cardiopulmonary bypass time) in 2 patients and might have affected the outcome in 1 of them, a neonate with transposition of the great arteries and a preoperatively undiagnosed intramural coronary artery, who died postoperatively despite a technically adequate repair. CONCLUSIONS: In many infants and children, diagnostic work-up before open heart operations could be adequately based on an exclusively noninvasive basis by relying on echocardiography alone.     

Intraoperative use of dual-chamber demand pacemakers for open heart operations

The availability of external atrioventricular sequential pacemakers has improved the management of patients with sinus bradycardia, junctional rhythm, and atrioventricular block. However, these pacemakers are of less value in patients with postoperative heart block and accelerated atrial rhythms. The temporary use of a modified explanted dual-chamber demand pacemaker may counteract that problem by providing atrially triggered, P-wave-synchronous ventricular pacing. We report 2 patients in whom the temporary use of the dual-chamber demand pacemaker greatly facilitated weaning from cardiopulmonary bypass after coronary artery bypass grafting.     

Efficacy of antibiotic prophylaxis in high risk gastroduodenal operations

A double-blind, prospective and randomized clinical trial of the efficacy of antibiotic prophylaxis in gastroduodenal operations was studied in 39 patients over an 18 month period. All patients had clinical features that placed them at high risk for the development of postoperative wound or intraabdominal sepsis. In the placebo group of 20 patients seven gastric-related infections developed, while 1 of the 19 patients who received perioperative cefamandole had one gastric-related infection (p < 0.01). The responsible microorganisms were those that are normal components of the oral or intestinal microflora. Nongastric-related infections and deaths did not differ significantly in the two study groups. The results of this study confirm the efficacy of the use of short-term perioperative antibiotic prophylaxis in patients undergoing gastroduodenal surgery for bleeding duodenal or gastric ulcer, obstructing duodenal ulcer, gastric ulcer or malignancy.