Richard A. Ott

Aggressive preoperative use of intraaortic balloon pump in elderly patients undergoing coronary artery bypass grafting

BACKGROUND The use of the intraaortic balloon pump (IABP) in patients undergoing coronary artery bypass grafting has been traditionally associated with a high complication rate and adverse outcomes. However, recent reports show that many of these catastrophic outcomes can be avoided by preoperatively placing the IABP in high-risk patients. To further validate these reports, we defined a set of liberal criteria for preoperative IABP insertion and applied them to a series of elderly patients (70 years or older) undergoing isolated coronary artery bypass grafting. METHODS Two hundred six consecutive patients who underwent isolated coronary artery bypass grafting with cardiopulmonary bypass were retrospectively reviewed. A rapid recovery protocol emphasizing reduced cardiopulmonary bypass time, an anesthetic protocol for early extubation, perioperative administration of corticosteroids and thyroid hormone, and aggressive diuresis was applied to all patients. Patients who required an urgent operation because of failed percutaneous transluminal coronary angioplasty, a critical left main stenosis (70% or greater), pronounced left ventricular dysfunction (left ventricular ejection fraction 40% or less), or unstable angina refractory to medical therapy or who required an emergency reoperation received preoperative IABP support. RESULTS The 30-day mortality rate for the entire group was 4.4%. There were 97 patients (47%) who received a preoperative IABP (group II) in comparison with 109 patients (53%) who did not fulfill the preoperative insertion criteria (group I). Patients in group II had a lower left ventricular ejection fraction (mean, 46% versus 59%, p<0.001) and a higher incidence of congestive heart failure (35% versus 17%, p<0.01) and acute myocardial infarction (37% versus 17%, p<0.01) than patients in group I. The average postoperative hospital length of stay for patients in group II was slightly longer than for those in group I (9.0+/-10.5 versus 6.0+/-3.7 days, p<0.01). However, there were no statistically significant differences in complication or mortality rates between the two groups. Only 2 patients (2.2%) had complications related to IABP insertion. Lower extremity ischemia occurred in both patients, and both were treated successfully with thromboembolectomy. CONCLUSIONS Liberal preoperative insertion of the IABP can be performed safely in high-risk elderly patients undergoing coronary artery bypass grafting, with results comparable to those in lower risk patients.

Rapid Recovery After Coronary Artery Bypass Grafting: Is the Elderly Patient Eligible?

BACKGROUND Rapid recovery protocols after coronary artery bypass grafting have been applied successfully to young patients with normal ventricular function. However, the success of such protocols when applied to the elderly population has not been thoroughly validated, and at some centers there is still reluctance in allowing elderly patients to be discharged early from the hospital. METHODS One hundred fifty-two consecutive younger patients (< 70 years) were compared retrospectively with 167 consecutive elderly patients (> or = 70 years) who underwent isolated coronary artery bypass grafting using cardiopulmonary bypass. A rapid recovery protocol emphasizing an anesthetic protocol for early extubation, reduced cardiopulmonary bypass time, and perioperative administration of corticosteroids and thyroid hormone was applied to all patients. The protocol also emphasized early identification and management of postoperative atrial fibrillation, a proactive negative fluid balance, rapid return of bowel function, mobilization of the patient, and aggressive use of the intraaortic balloon pump preoperatively. RESULTS The 30-day mortality rate for the younger group of patients was 3.3% (Parsonnet risk 7.2 +/- 6.2), compared with 4.2% (Parsonnet risk, 17.7 +/- 6.8) for the elderly group of patients. There were no statistically significant differences in the 30-day mortality rates or postoperative complications between the elderly and younger patient groups. Rapid recovery with discharge before the fifth postoperative day was achieved in 19% of the elderly, in comparison with 48% of the younger patients (p < 0.001). The younger patients were discharged earlier after operation than the older patients (5.7 +/- 5.2 versus 8.0 +/- 8.5 days; p < 0.01). CONCLUSIONS Application of the rapid recovery protocol helped expedite recovery for all patients regardless of age, acuity of illness, or associated conditions. Although younger patients had a significantly shorter postoperative length of hospital stay, older patients performed well and are suitable candidates for rapid recovery protocols.

Clinical choices for circulatory assist devices.

Approximately 1.0% of open heart surgery patients become unweanable from cardiac bypass during the surgical procedure. In addition, nearly 20% of patients accepted for cardiac transplantation die while waiting for a donor heart. Pulsatile pneumatic ventricular assist devices (VADs) provide a realistic solution to these dilemmas. Currently, there are five manufacturers who are competing for the major market share in the clinical use of these devices. Novacor, Thermetics, Thoratec, Symbion, and Abiomed all have competitive VAD systems. Because no one system is optimal for all patients, the limitations, similarities, and strengths of each system should be known to enhance the patients outcome when using these devices. Successful use of VAD systems, either as a bridge to transplantation or to ventricular recovery, is best approached by adherence to strict patient selection. Once instituted, VAD management centers on detailed attention to anticoagulation and prompt diagnosis and treatment of various complications.

Rapid Recovery of Octogenarians Following Coronary Artery Bypass Grafting

Abstract Background: Rapid recovery protocols for coronary artery bypass grafting (CABG) have resulted in major decreases in postoperative hospital length of stay (LOS) when applied to younger patients undergoing elective procedures. However, the effectiveness of rapid recovery protocols when applied to octogenarians has not been thoroughly studied. Methods: Thirty‐seven consecutive octogenarians underwent isolated CABG utilizing cardiopulmonary bypass (CPB). A protocol emphasizing preoperative placement of the intra‐aortic balloon pump, reduced CPB time, early extubation, perioperative steroids, thyroid hormone, and aggressive postoperative diuresis was used. Results: The 30‐day operative mortality for the entire series was 5.4%. Twenty‐five patients (71%, group I) were discharged in < 10 days postoperatively (average LOS of 6.3 ± 1.6 days), while ten patients (29%, group II) were discharged at 10 or more days postoperatively (average LOS of 20.3 ± 8.0, p < 0.001). Patients in group II were found to have a higher incidence of obesity (50% vs 4%, p < 0.01), symptomatic peripheral vascular disease (60% vs 8%, p < 0.01), and preoperative ambulatory difficulties (50% vs 0%, p < 0.01). The incidence of complications was 31% for the entire series, with no differences between the groups. Conclusion: Octogenarians performed well under a rapid recovery protocol, with 71% being discharged in < 10 days postoperatively, while patients with obesity, symptomatic peripheral vascular disease, and ambulatory difficulties rehabilitated more slowly.

Initial clinical evaluation of carotid artery laser endarterectomy

Clinical study of carotid artery laser endarterectomy began April 15, 1988. This report describes the first 10 cases that were performed in nine patients (five men and four women, mean age 70 years). Indications were asymptomatic stenosis (5), transient ischemic attacks (4), and stroke in evolution (1). There were two emergency cases and eight elective cases (including one reoperative case). Surgical exposure, systemic heparinization, vascular control, and a longitudinal arteriotomy were used. The cleavage plane between atheromas and media was developed with argon ion laser radiation (488 and 514.5 nm) directed through a 300 microns quartz fiber at power 1.0 W. Laser radiation was used to cut the atheromas out of the arteries and weld the end points. Residual atheromatous debris were vaporized with individual laser exposures. Arteriotomies were closed with sutures, and blood flow was restored. The endarterectomies were 3.9 +/- 1.1 cm long and required 330 +/- 97 joules. Mean clamp time was 22.5 +/- 7.9 minutes. Shunts were used in two cases. There were no arterial perforations or injuries as a result of laser light. Complications were hematoma (1), respiratory arrest (1), and transient neurologic deficit (1). Carotid endarterectomy is technically feasible with argon ion laser radiation. In the present series, postoperative observations, averaging 12 months and ranging from 5 to 19 months, have shown satisfactory results. No angiographic follow-up examinations were carried out.

Concepts in the application of pneumatic ventricular assist devices for ischemic myocardial injury

&NA; The clinical results of “bridge‐to‐recovery” from ischemic myocardial injury using pneumatic ventricular assist devices (VADs) have been disappointing, because no significant improvement in the hospital discharge rate (25%) has been observed during the past 10 years. Interestingly, similar results have been reported using the less sophisticated and more widely available centrifugal pumps. It is well recognized that appropriate patient selection and early device implantation are important determinants of patient survival; however, it is less clear why there is a lack of difference in the results between pneumatic VADs and the centrifugal pumps. The reasons for the lack of difference in the results between pneumatic VADs and centrifugal pumps are multifactorial, and to some extent may be due to a conservative approach in the application of the more capable pneumatic VADs. In an effort to provide a more effective approach to the clinical application of pneumatic VADs for bridge‐to‐recovery, two pneumatic devices (the Jarvik 7‐70 total artificial heart and the Symbion acute VAD) were functionally characterized using an in vitro mock circulatory system. The performance under pneumatic VAD asynchronous pumping compared to electrocardiogram synchronous counterpulsation was also evaluated. Based upon the results obtained, a two phase approach was developed. In the initial phase (i.e., the first 12‐48 hrs), device output is maximized through asynchronous pumping to rapidly reverse the effects of cardiogenic shock. During the second phase (i.e., after hemodynamic stabilization and early evidence of end‐organ recovery), electrocardiogram synchronous counterpulsation is used to focus more specifically on recovery of the heart. Unlike previous approaches, this two phase approach provides a more physiologic setting to enhance recovery by effectively reducing myocardial oxygen consumption through asynchronous pumping (Phase 1) and maximally increasing myocardial oxygen delivery through electrocardiogram synchronous counterpulsation (Phase 2). This approach, coupled with appropriate patient selection and early device institution, may improve recovery in the clinical setting of reversible myocardial injury. ASAIO Journal 1995; 41:162‐168.

Simplified Parsonnet Risk Scale Identifies Limits to Early Patient Discharge

Abstract Background: Fast‐track recovery after coronary artery bypass surgery has influenced patient care positively. Predicting patients who fall off track and require prolonged (≥7 days) hospitalization remains uncertain. The Parsonnet risk assessment score is effective in predicting length of stay, but is limited by inaccurate subdivision of risk categories. We simplified the Parsonnet risk scale to better identify patients eligible for fast‐track recovery. Method: The cases of 604 consecutive patients who underwent isolated coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPS) were reviewed retrospectively. A rapid recovery protocol emphasizing reduced CPB time, preoperative intra‐aortic balloon pump (IABP) criteria, and atrial fibrillation prophylaxis was applied to all patients. The five original divisions of the Parsonnet risk scale were reduced to three risk categories: Low (0–10; Group A), Intermediate (11–20; Group B), High (> 20; Group C). Comparisons of progressive risk categories were analyzed to identify predictive factors associated with fast‐track outcomes. Results: The thirty‐day operative mortality for the entire group was 3.6%. Three clinical features were identified that distinguished risk progression—female gender, reoperative CABG, and increased age. Additionally, the presence of diabetes (p < 0.05), congestive heart failure (p < 0.01), and peripheral vascular disease (p < 0.001) distinguished Groups A and B, while acute myocardial infarction (p < 0.05) influenced outcomes in Group C. Group A (48%) mean risk score 5.9 ± 3.2 was compared to Group B (34%) 14.8 ± 2.6, which was further compared to Group C (18%) 26.4 ± 2.8. The mean length of stay for Group A (5.3 ± 4.1 days) was notably less than Group B (6.1 ± 4.7 days; p < 0.05); however, both groups responded favorably to fast‐track techniques. Group C did not respond comparably (9.2 ± 9.2 vs 6.1 ± 4.7 days; p < 0.001) and experienced prolonged recovery. The simplified Parsonnet risk scale did not identify differences in operative mortality and revealed only pneumonia (p < 0.05) and atrial fibrillation (p < 0.01) to be greater in Group C. As risk increased, significantly less revascularization was performed (Group A 3.6 ± 1.2 grafts/patient vs Group B 3.3 ± 1.2 [p < 0.01]; Group B 3.3 ± 1.2 vs Group C 2.5 ± 1.0 [p < 0.001]). Conclusion: A simplified Parsonnet risk scale (three categories) is an effective tool in identifying factors limiting fast‐track recovery. Low‐ and intermediate‐risk patients represent the majority (82%) and respond well to fast‐track methods. High‐risk patients (18%) are limited by a greater percentage of female patients, reoperative CABG, and the very elderly, resulting in fast‐track failure. Strategies to improve recovery in high‐risk patients may include evolving off‐pump techniques.

Regional Myocardial Perfusion of Cardioplegic Solutions

We compared the regional myocardial perfusion of blood cardioplegic solution (BCP) and crystalloid cardioplegic solution (CCP) in 14 mongrel dogs. Cardiopulmonary bypass was established at 28 degrees C, and a hydraulic occluder was placed around the proximal left anterior descending (LAD) coronary artery. In group 1 (N = 7) collateral coronary arteries were ligated; in group 2 (N = 7) collateral coronary arteries were left in situ. After the aorta was clamped, BCP and CCP were alternately perfused at 200 ml/min. The occluder was inflated to produce moderate, severe, and critical LAD stenosis, and regional perfusion was measured by xenon-133 washout with the Silicon Avalanche Radiation Detector. BCP infusion produced a consistently higher aortic pressure, but CCP flow was better than BCP flow under all conditions, particularly without coronary collaterals (p less than .05). Regional myocardial perfusion of CCP is superior to BCP.