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.     

Thoracic epidural anaesthesia for coronary artery bypass graft surgeryEffects on postoperative complications

We have performed a retrospective analysis of the peri-operative course of 218 consecutive patients who underwent routine coronary artery bypass graft surgery in this institution. All patients received a standardised general anaesthetic using target-controlled infusions of alfentanil and propofol. One hundred patients also received thoracic epidural anaesthesia with bupivacaine and clonidine, started before surgery and continued for 5 days after surgery. The remaining 118 patients received target-controlled infusion of alfentanil for analgesia for the first 24 h after surgery, followed by intravenous patient-controlled morphine analgesia for a further 48 h. Using computerised patient medical records, we analysed the frequency of respiratory, neurological, renal, gastrointestinal, haematological and cardiovascular complications in these two groups. New arrhythmias requiring treatment occurred in 18% of the thoracic epidural anaesthesia group of patients compared with 32% of the general anaesthesia group (p = 0.02). There was also a trend towards a reduced incidence of respiratory complications in the thoracic epidural anaesthesia group. The time to tracheal extubation was decreased in the epidural group, with the tracheas of 21% of the patients being extubated immediately after surgery compared with 2% in the general anaesthesia group (p < 0.001). There were no serious neurological problems resulting from the use of thoracic epidural analgesia.     

Thoracic epidural analgesia in a patient with bilateral phaeochromocytoma undergoing coronary artery bypass grafting

A patient suffering from phaeochromocytoma and coronary artery stenoses needed coronary artery bypass grafting before adrenalectomy. High thoracic epidural analgesia (T1-T2) with bupivacaine and sufentanil in combination with general anaesthesia was used. Plasma adrenaline and noradrenaline concentrations decreased during the period before bypass grafting compared to the baseline value and no important haemodynamic changes were seen during this period. Thoracic epidural analgesia failed to suppress the release of catecholamine during the bypass period. After the operation, the plasma catecholamine concentrations returned to the baseline value. Excellent analgesia (visual analogue scale = 1-2) was achieved with a postoperative epidural, but the plasma catecholamine concentration increased considerably.     

Thoracic epidural analgesia in aortocoronary bypass surgery I: haemodynamic effects

Tachycardia and hypertension may cause myocardial ischaemia in patients with coronary heart disease going through major surgery. Thoracic epidural analgesia (TEA) has been reported to be beneficial in this situation. The haemodynamic effects of TEA in aortocoronary bypass surgery were investigated in 30 male patients < 65 years old and with ejection fraction > 0.5. They were randomized into 3 groups: the high dose fentanyl (HF) group receiving high–dose fentanyl (55 μg kg^-1) anaesthesia, the HF + TEA group receiving the same fentanyl dose + TEA with 10 ml bupivacaine 5 mg ml^-1 followed by 4 ml every hour, and the low dose fentanyl (LF) + TEA group receiving low–dose fentanyl (15 μg kg^-1) anaesthesia + TEA. Haemodynamic parameters, the use of vasoactive and inotropic drugs and fluid balance were followed during the operation and for 20 h postoperatively. Before bypass the only significant difference between groups was a higher mean pulmonary arterial pressure in the HF + TEA group and a lower systemic vascular resistance (SVR) in the LF + TEA group, both compared to the HF group. 89% of epidural group patients needed small doses of ephedrine whereas more HF group patients were given nitroglycerine. During bypass SVR and mean arterial pressure (MAP) were significantly higher and pump flow lower in the HF group compared to the LF + TEA group. More ketanserin to HF group patients and methoxamine to epidural group patients were given. After bypass heart rate increased in all groups. Lower MAP 0.5 h after bypass and higher filling pressures in the early post bypass period in the epidural groups, most pronounced in the HF + TEA group, were noted. More propranolol, nitroglycerine and sodium nitroprusside were given to patients in the HF group. No difference in intraoperative fluid balance between groups was seen. Our results suggest more easy control of perioperative hypertension and tachycardia with TEA. This was achieved without haemodynamic side effects of clinical importance.     

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.     

曲马多在不停跳冠状动脉旁路移植术后镇痛中的应用

目的 探讨曲马多用于不停跳冠状动脉旁路移植术(OPCABG)后镇痛的有效性与安全性.方法 OPCABG患者64例,随机均分为两组,术中均吸入1％七氟醚和静注舒芬太尼维持麻醉,关闭胸骨前分别采用曲马多(T组)和舒芬太尼(S组)自控镇痛.记录患者疼痛VAS评分、镇静评分及不良反应.结果 T组静息VAS评分显著低于S组(P＜0.05).两组术后清醒时间和机械通气时间差异无统计学意义.结论 曲马多用于OPCABG术后镇痛具有良好的镇痛效果.     

A prospective randomized study of intraoperative thoracic epidural analgesia in off-pump coronary artery bypass surgery

Objective

The purpose of this study was to test the hypothesis that general anesthesia (GA) plus thoracic epidural anesthesia (TEA) has no impact on the outcomes of off-pump coronary artery bypass surgery (OPCABs) compared to GA followed by patient-controlled TEA (PCTEA), while GA plus TEA leads to a higher requirement for vasoactive drug use.

Methods

Sixty-four patients, American Society of Anesthesiologists physical status II and III, who were scheduled for elective OPCABs, were offered an epidural catheter inserted at the T2?C3 interspace and then randomized into 1 of 2 groups according to whether TEA was applied intraoperatively. The TEA_perio group received GA plus TEA, while the TEA_post group received GA alone. All groups had postoperative PCTEA. The number of requirements for vasoactive drugs and the extubation times were recorded. The analgesic effect was monitored by visual analog scale (VAS) pain scores. Heart rate, blood pressure, and blood gases were also monitored. The data are presented as mean values?±?standard deviation, or medians with quartiles.

Results

The proportion of vasoactive drug use was significantly higher in the TEA_perio group intraoperatively (before or during completion of anastomoses: 59.4 vs. 20.7%, p?=?0.004; after completion of anastomoses: 53.1 vs. 17.2%, p?=?0.007). There was no statistically significant difference in extubation times or VAS scores between the 2 groups.

Conclusions

We conclude that GA plus TEA has no impact on the outcomes of OPCABs, while its use leads to a higher requirement for vasoactive drug use. GA followed by PCTEA facilitates the anesthesia administration, while it does not affect the extubation time and the postoperative analgesic effect.     

Free arterial graft in coronary artery bypass surgery

Free arterial graft of the internal mammary artery (IMA) and the gastroepiploic artery (GEA) has been utilized for coronary artery bypass grafting in 10 patients during 44 months period. There were 6 males and 4 females and age ranged 42 to 73 year old with the mean of 60.8 year old. Eight IMA and 2 GEA were used as a free graft. Sites of distal anastomosis of the free graft were 3 at anterior descending arteries, 3 at diagonal branches and 4 at circumflex arteries. Sites of proximal anastomosis of those grafts were ascending aorta in one, concomitantly utilized saphenous vein graft in 5 and in situ IMA graft in 4 patients. Mean number of grafts was 2.9 (2-5) and mean aortic cross clamp time was 56.2 minutes (16-90 minutes). There was neither operative death, nor perioperative myocardial infarction and intra-aortic balloon pumping was not required. Postoperative angiography was made in 9 patients within 3 postoperative months. Eight (89%) free arterial grafts were patent. Relief of angina was obtained in all patients. We concluded that the complete revascularization with only arterial graft can be achieved more widely by utilizing the free arterial graft with an acceptable patency.