High thoracic epidural anesthesia for off-pump coronary artery bypass surgery

OBJECTIVE: To assess the feasibility of high thoracic epidural anesthesia combined with sevoflurane for off-pump coronary artery bypass surgery and to evaluate the postoperative pain control, side effects, and perioperative hemodynamics. DESIGN: Retrospective review of prospectively collected data. SETTING: A university teaching hospital. PARTICIPANTS: One hundred six consecutive patients receiving thoracic epidural combined with sevoflurane. INTERVENTION: From November 1999, the patients undergoing off-pump coronary artery bypass grafting were offered the epidural-inhalation anesthetic approach. MEASUREMENTS AND MAIN RESULTS: Insertion of the epidural catheter was successful in all but 2 patients; 1 bloody tap occurred and the dura was never punctured, although 1 patient presented with postoperative paraplegia. An emergency spinal cord nuclear magnetic resonance excluded signs of medullary compression caused by epidural or spinal hematoma. Visual analog scale scores for pain during the first 24-hour period were < 2 in all patients. Mean time to extubation was 4.6 +/- 2.9 hours. The average intensive care unit stay was 1.5 +/- 0.8 days. Incidences of perioperative myocardial infarction, myocardial ischemia, and atrial fibrillation were 2.8%, 7.5%, and 10.6%, respectively. Two patients died: 1 from multiorgan failure and the other from myocardial infarction. Heart rate, mean arterial pressure, cardiac index, and systemic vascular resistance were not affected by thoracic epidural alone. Mean arterial pressure and cardiac index decreased (p < 0.05) when general anesthesia was induced and remained stable thereafter. Neither heart rate nor systemic vascular resistance changed from baseline during operation. CONCLUSIONS: Thoracic epidural as an adjunct to general anesthesia is a feasible technique in off-pump coronary artery bypass surgery. It induces intense postoperative analgesia and does not compromise central hemodynamics.     

Prospective randomized trial of high thoracic epidural analgesia for coronary artery bypass surgery

BACKGROUND: Postoperative pain may be severe after coronary artery bypass surgery. High thoracic epidural analgesia (HTEA) provides intense analgesia. METHODS: Eighty patients were randomized to HTEA or intravenous morphine analgesia (control). Patients received coronary artery bypass surgery (CABG) with cardiopulmonary bypass. Pain was measured by visual analogue scale 0 to 10. Psychologic morbidity, intraoperative hemodynamics, ventricular function, lung function, and physiotherapy cooperation were also assessed. On the third postoperative day HTEA and morphine were ceased and only oral medications were used. Acetaminophen, indomethacin, and tramadol were allowed as supplemental analgesics in both groups. RESULTS: The primary endpoint of pain scores was significantly less with HTEA on postoperative days 1 and 2 at rest, 0.02 +/- 0.2 versus 0.8 +/- 1.8 (p = 0.008) and 0.1 +/- 0.4 versus 1.2 +/- 2.7 (p = 0.022), respectively, and with coughing 1.2 +/- 1.7 versus 4.4 +/- 3.1 (p < 0.001) and 1.5 +/- 2.0 versus 3.6 +/- 3.1 (p = 0.001), respectively. When HTEA and morphine were ceased on day 3, there were no significant differences. The secondary endpoints of postoperative depression (p = 0.033) and posttraumatic stress subscales (p = 0.021) of the Minnesota Multiphasic Personality Inventory were lower with HTEA. Extubation occurred earlier with HTEA, 2.6 versus 5.4 hours (p < 0.001). HTEA showed improved physiotherapy cooperation (p < 0.001), arterial oxygen tension (p = 0.041), and peak expiratory flow rate (p = 0.001). Mean arterial pressure was lower with HTEA (p = 0.036), otherwise there were no differences in intraoperative hemodynamics or ventricular function. CONCLUSIONS: Epidural analgesia reduces pain after coronary operation and is associated with improved physiotherapy cooperation, earlier extubation, and reduced risk of depression and posttraumatic stress.     

Routine immediate extubation for off-pump coronary artery bypass grafting without thoracic epidural analgesia

BACKGROUND: The expansion of coronary surgery on the beating heart without cardiopulmonary bypass has led to increasing interest in ultra-fast track anesthesia, allowing extubation of the patient in the operating theater. The techniques described to date combined general anesthesia with thoracic epidural analgesia. We report the routine application of a technique that allows immediate extubation in the majority of patients undergoing off-pump coronary artery bypass grafting without thoracic epidural analgesia. METHODS: Fast-track anesthesia using an ultra-shortacting opiate remifentanil, without epidural catheter insertion, was used in 160 unselected patients undergoing off-pump coronary artery bypass grafting (aged 43 to 83 years, mean 65 years). There were an average of 2.2 bypass procedures per patient, with the left internal mammary artery used in 93%. Contraindications to immediate extubation were (except for failure to meet standard extubation criteria) hemodynamic instability and persistent bleeding at the end of operation. Satisfactory postoperative pain control was achieved by continuous remifentanil (0.0125 to 0.05 microg x kg(-1) x min(-1)). RESULTS: Operating theater extubation within 10 minutes of the end of operation was feasible in 150 patients (94%). Five patients (3%) were extubated within 2 hours, and the remaining 5 patients (3%) were converted to standard anesthesia. There were no deaths during hospitalization. Major complications included myocardial infarction and transient ischemic attacks (2 patients each). No pulmonary complications were seen. Episodes of atrial fibrillation occurred in 21% of the patients undergoing operation. CONCLUSIONS: Immediate extubation is possible in most patients after off-pump coronary artery bypass grafting even without thoracic epidural analgesia. We believe this type of less invasive cardiac anesthesia is safe and promising.     

Economic outcome of off-pump coronary artery bypass surgery: a prospective randomized study

Background. Emphasis on cost containment in coronary artery bypass surgery is becoming increasingly important in modern hospital management. The revival of interest in off-pump (beating heart) coronary artery bypass surgery may influence the economic outcome. This study examines these effects.

Methods. Two hundred patients undergoing first-time coronary artery bypass surgery were prospectively randomized to either conventional cardiopulmonary bypass and cardioplegic arrest or off-pump surgery. Variable and fixed direct costs were obtained for each group during operative and postoperative care. The data were analyzed using parametric methods.

Results. There was no difference between the groups with respect to pre- and intraoperative patient variables. Off-pump surgery was significantly less costly than conventional on-pump surgery with respect to operating materials, bed occupancy, and transfusion requirements (total mean cost per patient: on pump, $3,731.6 ± 1,169.7 vs off-pump, $2,615.13 ± 953.6; p < 0.001). Morbidity was significantly higher in the on-pump group, which was reflected in an increased cost.

Conclusions. Off-pump revascularization offers a safe, cost-effective alternative to conventional coronary revascularization with cardiopulmonary bypass and cardioplegic arrest.     

A prospective randomized study of the potential benefits of thoracic epidural anesthesia and analgesia in patients undergoing coronary artery bypass grafting

We performed an open, prospective, randomized, controlled study of the incidence of major organ complications in 420 patients undergoing routine coronary artery bypass graft surgery with or without thoracic epidural anesthesia and analgesia (TEA). All patients received a standardized general anesthetic. Group TEA received TEA for 96 h. Group GA (general anesthesia) received narcotic analgesia for 72 h. Both groups received supplementary oral analgesia. Twelve patients were excluded-eight in Group TEA and four in Group GA-because of incomplete data collection. New supraventricular arrhythmias occurred in 21 of 206 patients (10.2%) in Group TEA compared with 45 of 202 patients (22.3%) in Group GA (P = 0.0012). Pulmonary function (maximal inspiratory lung volume) was better in Group TEA in a subset of 93 patients (P < 0.0001). Extubation was achieved earlier (P < 0.0001) and with significantly fewer lower respiratory tract infections in Group TEA (TEA = 31 of 206, GA = 59 of 202; P = 0.0007). There were significantly fewer patients with acute confusion (GA = 11 of 202, TEA = 3 of 206; P = 0.031) and acute renal failure (GA = 14 of 202, TEA = 4 of 206; P = 0.016) in the TEA group. The incidence of stroke was insignificantly less in the TEA group (GA = 6 of 202, TEA = 2 of 206; P = 0.17). There were no neurologic complications associated with the use of TEA. We conclude that continuous TEA significantly improves the quality of recovery after coronary artery bypass graft surgery compared with conventional narcotic analgesia.     

A prospective, randomized study of endothelin and postoperative recovery in off-pump versus conventional coronary artery bypass surgery

OBJECTIVE: The objectives are 2-fold: (1). to serially determine endothelin (ET) levels in arterial vascular compartments in patients undergoing coronary artery bypass surgery using either cardiopulmonary bypass or off-pump techniques, and (2). to define potential relationships between endothelial levels and specific perioperative parameters of patient recovery. METHODS: In a prospective, randomized study, endothelin plasma content was measured from patients undergoing coronary artery bypass grafting using either off-pump techniques (OPCAB group, n = 25) or conventional cardiopulmonary bypass (CPB group, n = 25) before surgery, before and after coronary artery anastomosis, and 6 and 24 hours postoperatively. Specific indices of patient recovery including pulmonary artery pressures, ventilation requirement, and hospital stay were documented for patients in both study groups. RESULTS: Postoperative systemic arterial ET levels were significantly increased by 200% in the CPB group and 50% in the OPCAB group. ET levels remained significantly higher in the CPB group relative to the OPCAB group throughout the postoperative period of observation (p < 0.05). Pulmonary artery pressures, ventilation requirement, and hospital stay were significantly increased in patients in the CPB group. CONCLUSIONS: Postoperative ET levels were higher in patients who underwent CPB for coronary artery bypass surgery. Increased ET in the postoperative period may contribute to a more complex recovery from coronary artery bypass surgery in patients undergoing cardiopulmonary bypass.     

Lumbar versus thoracic epidural buprenorphine for postoperative analgesia following coronary artery bypass graft surgery

BACKGROUND: Thoracic epidural analgesia (TEA) is reported to provide effective analgesia following cardiac surgery. We compared the effect of buprenorphine (BN) through the lumbar and thoracic epidural routes for postoperative analgesia following coronary artery bypass graft surgery (CABG). METHODS: Forty patients with normal left ventricular ejection fraction scheduled for CABG were randomly divided into two groups, the TEA group (n = 19) and the lumbar epidural analgesia (LEA) group (n = 20). For postoperative pain relief they received epidural BN 0.15 mg at the first demand for pain relief following extubation. A top-up dose of BN 0.15 mg was administered in cases where visual analogue scale (VAS) score was > 3 at 1 h after first dose. Subsequent breakthrough pain was treated with 30 mg intramuscular ketorolac tromethamine (ketorolac). Pain assessed by VAS score on a 0-10 scale, respiratory rate, FEV1, FVC, mean arterial blood pressure, cardiac index, PaO2 and PaCO2 were measured at frequent intervals. Side effects of epidural opioids were noted. RESULTS: Both groups were comparable in demographic characteristics, had similar VAS scores from 1 to 24 h postoperatively, required similar amounts of intramuscular ketorolac for break-through pain and had comparable pulmonary functions and side effects. CONCLUSION: This study shows that BN by the lumbar epidural route for analgesia after CABG compares favourably with the same drug through the thoracic route in terms of quality of analgesia and incidence of side effects.     

A prospective evaluation of hemodynamic instability during off-pump coronary artery bypass surgery

OBJECTIVE: Despite recognized hemodynamic derangements during cardiac displacement, most patients appear to tolerate the off-pump procedure well. However, some patients unpredictably become hemodynamically unstable requiring emergency cardiopulmonary bypass or intra-aortic balloon pump support. After an experience of 5306 multivessel off-pump coronary artery bypasses (OPCABs), this study was undertaken to determine the factors that would identify the patients who were at a higher risk for the procedure. DESIGN: Prospective clinical investigation. SETTING: Tertiary care academic cardiac care center. PARTICIPANTS: Five hundred consecutive patients undergoing multivessel OPCAB from September to December 2001. INTERVENTIONS: Various cardiac and extracardiac factors were charted in prespecified data-entry forms. Multiple logistic regression analysis was done to determine if any identifiable factors were predictors of a higher risk of unacceptable hemodynamic instability during OPCAB. Institution of IABP support or conversion to CPB were the endpoints of the study. MEASUREMENTS AND MAIN RESULTS: Of the 500 patients studied, significant hemodynamic instability developed in 24 (4.8%) patients. IABP support was instituted in 16 (3.2%) patients, and 8 (1.6%) were converted to CPB. Stepwise logistic regression identified ejection fraction <25% (p < 0.001), myocardial infarction of <1-month duration (p = 0.009), congestive heart failure (p = 0.016), and preoperative hemodynamic instability (p = 0.057) as predictors of conversion during OPCAB. CONCLUSIONS: Patients with low left ventricular ejection fraction <25%, myocardial infarction of <1-month duration, congestive heart failure, or preoperative hemodynamic instability constitute the high-risk group for OPCAB.     

胸段硬膜外阻滞对全麻下非停跳冠状动脉搭桥术病人心肌保护作用

目的观察胸段硬膜外阻滞（TEA）对冠心病行非停跳冠状动脉搭桥术（OPCAB）病人血浆内皮素（ET）及心钠素（ANP）的影响。方法20例拟行OPCAB病人分为两组：A组为单纯全麻组;B组为TEA复合全麻组。采用放免法测定术前、术后1h、术后24h及术后48h血浆ET及ANP浓度,记录血液动力学参数及所用血管活性药剂量。结果B组术后1、24、48hET及ANP显著低于A组（P〈0．05）,血液动力学稳定,所用血管活性药物少（P〈0．05）。结论TEA能抑制麻醉手术所致的应激反应,对OPCAB病人的心脏有保护作用。     

High thoracic epidural anesthesia in coronary artery bypass surgery: a propensity-matched study

OBJECTIVES: To assess if 2 different anesthesia strategies, high-thoracic epidural anesthesia (HTEA) plus inhalation anesthesia and total intravenous anesthesia (TIVA) with sufentanil/propofol had different influence on outcomes of coronary artery bypass graft (CABG) surgery patients. DESIGN: Retrospective comparison of outcomes between HTEA and TIVA patients using propensity score pair-wise matching of patients. SETTING: A university teaching hospital. Participants: A study of 1,473 consecutive patients undergoing elective CABG surgery; of these, 476 (32%) received HTEA combined with inhalation anesthesia, whereas 997 (68%) underwent TIVA alone. INTERVENTIONS: The patients undergoing CABG surgery were offered the epidural-inhalation anesthetic approach. MEASUREMENTS AND MAIN RESULTS: Propensity matching yielded 389 pairs of patients. Patients were well matched in preoperative and operative features. Postoperative mortality, myocardial infarction, stroke, acute renal failure rates, and intensive care unit (ICU) stay were not statistically different in HTEA and TIVA groups. On the other hand, patients treated with HTEA had shorter ventilation times (5.8 +/- 3.11 v 6.9 +/- 5.0 hours, HTEA and TIVA, respectively, p < 0.001); in addition, vasoconstrictors were more frequently used in cases of HTEA, whereas vasodilators were mainly used with TIVA both intra- and postoperatively. No neurologic complications related to the use of HTEA were observed. CONCLUSIONS: HTEA and TIVA provided similar early outcomes after CABG surgery, and there were no major differences between these 2 strategies in the average risk CABG patient populations. Although HTEA did not cause neurologic problems and yielded a significant reduction in time to extubation, a consistent benefit over standard techniques could not be shown.     

High thoracic epidural anesthesia as the sole anesthetic for performing multiple grafts in off-pump coronary artery bypass surgery

OBJECTIVES: The feasibility of the use of high thoracic epidural anesthesia as a sole anesthetic in patients undergoing beating heart coronary revascularization avoiding general anesthesia was studied. DESIGN: A prospective study. SETTING: A tertiary care medical center. INTERVENTIONS: Fifteen patients underwent beating heart coronary artery revascularization without endotracheal general anesthesia, between October 2001 to May 2002, using high thoracic epidural anesthesia and analgesia. All the patients underwent epidural catheterization on the evening before the surgery. MEASUREMENTS AND MAIN RESULTS: The patients received 36 grafts (single, n = 5; double, n = 3; triple, n = 3; quadruple, n = 4). There were 3 female patients and 12 male patients with mean age of 60.6 +/- 5.9 years. Two patients underwent repeat coronary artery bypass. All the patients underwent off-pump coronary artery bypass graft surgery; 2 patients underwent grafting via left thoracotomy and the rest through a midsternotomy. There was no conversion to general anesthesia or cardiopulmonary bypass, and there was no mortality. Mean length of stay in the intensive care unit was 18.2 +/- 4.2 hours and in the hospital was 3.2 +/- 1.2 days. CONCLUSION: Experience confirms the feasibility of performing multiple coronary artery bypasses in conscious patients without endotracheal general anesthesia.