Thoracic epidural anesthesia for cardiac surgery

Canadian Journal of Anesthesia/Journal canadien d'anesthésie - Clearly, there is increasing evidence that TEA is a preferred method of adjunctive anesthesia for cardiac surgery. We have...     

Delays in discharge of vascular surgical patients: a prospective audit

Aim: To quantify delays in discharge for vascular surgical patients and identify causes of such delays. Methods: A prospective audit of delays in discharge of vascular surgical admissions over a 6‐month period was performed. Expected date and time of discharge was compared with actual date and time of discharge. Day‐case patients, patients who died during admission and patients not under the direct care of the vascular team were excluded. Results: There were 99 elective and 51 acute admissions accounting for 729 hospital bed days. The median (range) age was 72 years (21–92) and 94% of patients were living independently in the community. Forty‐seven percent of patients were discharged on the planned day and time, 21% on the planned day but at a later‐than‐predicted time and 32% were delayed by more than 1 day. Delays identified in this audit accounted for 135 bed days. Fifteen percent of delays were due to causes that can be improved by internal organization (e.g. delayed paperwork). The majority of the delays (85%) were due to external factors such as lack of rehabilitation beds or lack of placement facilities in nursing homes. Elderly patients and acute admissions were more likely to have long delays in discharge. Conclusion: Delays in discharge of vascular surgical patients use a lot of acute surgical bed days. Strategies to prevent delays in discharge should include not only improving internal organization and early identification and referral of patients who require rehabilitation/placement but also increased funding for such essential non‐acute services.     

Thoracic epidural anesthesia in the perioperative period

Thoracic epidural anesthesia and analgesia is a valuable tool in the perioperative period. Successful thoracic epidural catheter placement requires a thorough knowledge of anatomy and its role in the performance of thoracic epidural block. The paramedian approach in the mid-thoracic region (T5-8) makes use of definitive bony landmarks to facilitate successful thoracic epidural space identification. In properly trained hands using carefully defined endpoints, potential risks and complications of thoracic epidural placement are minimized.The physiologic response produced by thoracic epidural drug administration differs from lumbar epidural administration. This must be taken into consideration when dosing the catheter with opioids or local anesthetics. When used appropriately, thoracic epidural drug administration provides high quality anesthesia and postoperative analgesia, and has favorable effects on postoperative outcome. Copyright 2002, Elsevier Science (USA). All rights reserved.     

High thoracic epidural analgesia for cardiac surgery: an audit of 874 cases

Despite clinical use for over 10 years, high thoracic epidural analgesia for cardiac surgery remains controversial, due to a perceived increased risk of epidural haematoma resulting from anticoagulation for cardiac pulmonary bypass. There are no sufficiently large randomised studies to address this question and few large case series reported. For this reason, we conducted an audit of neurological complications related to high thoracic epidural analgesia during cardiac surgery in our institution between 1998 and end 2005. During this period 874 patients received epidural analgesia. There were no neurological complications attributable to epidural use. Our findings suggest that major neurological complications related to high thoracic epidural use during cardiac surgery are rare.     

Thoracic epidural anesthesia as an adjunct to general anesthesia for cardiac surgery: effects on ventilation-perfusion relationships.

OBJECTIVE: To determine the effects of thoracic epidural anesthesia (TEA) on ventilation-perfusion (VA/Q) relationships, atelectasis, and oxygenation before and after coronary artery bypass graft surgery (CABG). DESIGN: Prospective, controlled, unblinded, randomized trial. SETTING: Cardiothoracic clinic at a major university referral center. PARTICIPANTS: Twenty-eight patients undergoing elective CABG. INTERVENTIONS: Perioperative and postoperative TEA was added to general anesthesia (GA) in 14 patients, and 14 patients receiving GA alone served as controls. MEASUREMENTS AND MAIN RESULTS: VA/Q relationships were measured by the multiple inert gas elimination technique, and, 20 hours postoperatively, atelectasis was assessed by computerized tomographic scans. Arterial and mixed venous blood gases and hemodynamic variables were measured by standard techniques. TEA per se caused no change in shunt, VA/Q matching, or oxygenation. Induction of GA in the control group and induction of TEA caused similar reductions in mean arterial pressure. The TEA patients needed less morphine analgesia postoperatively and were extubated earlier. Extubation caused significant improvement in VA/Q matching. On the first postoperative day, a slight reduction in PaCO2 was seen in the TEA group, but no differences in shunt, VA/Q matching, or oxygenation compared with the GA group. Both groups showed extensive bilateral atelectasis. CONCLUSION: TEA can reduce respirator time and the need for morphine analgesics after CABG without negative effects on VA/Q matching, oxygenation, or atelectasis formation.     

胸部硬膜外麻醉复合吸入麻醉对腹部手术患者应激性高血糖的影响

目的观察胸部硬膜外麻醉复合异氟醚吸入麻醉对腹部手术患者应激性高血糖的影响。方法择期腹部手术患者40例,随机均分为两组,每组20例。I组和E组术中吸入异氟醚维持麻醉。E组患者诱导前T8~9椎间隙穿刺硬膜外置管,注入1%利多卡因5ml(不加肾上腺素)试验量,再注入利多卡因5~8 ml将阻滞平面调节到T4,以后每小时追加5~8 ml。于麻醉前30 min(T0)、手术90min(T1)、术后60min(T2)及术后1d(T3)、2d(T4)检测血糖(Glu)、红细胞醛糖还原酶(AR)、6-磷酸葡萄糖脱氢酶(G-6PD)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及血浆一氧化氮(NO)、血浆谷胱甘肽(GSH)、丙二醛(MDA)浓度。结果与T0时比较,T1~T3时两组Glu明显升高(P0.05),T3时I组AR、G-6PD、CAT活性与MDA浓度明显升高,NO、GSH浓度明显降低(P0.05)。与I组比较,T3时E组Glu、AR、G-6PD、CAT明显降低,NO明显升高(P0.05)。两组患者GSH-Px、SOD比较差异均无统计学意义。结论硬膜外麻醉可降低腹部手术患者术中、术后应激性高血糖。     

Thoracic epidural anesthesia and central hemodynamics in patients with unstable angina pectoris

The effects of high thoracic epidural anesthesia (TEA) on central hemodynamics as measured by pulmonary arterial catheterization were studied in nine patients with severe coronary artery disease and unstable angina pectoris. The patients were also treated with a combination of beta-blockers, calcium antagonists, and nitrates, as well as salicylates, low-dose heparin, and nitroglycerin infusion for greater than 24 hr. Management of pain with high TEA was started with the bolus epidural injection of 4.3 +/- 0.2 mL bupivacaine (5 mg/mL), which induced a sympathetic blockade from Th. During ischemic chest pain, pulmonary artery and pulmonary capillary wedge pressures were significantly increased. TEA, while relieving the chest pain, significantly decreased systolic arterial blood pressure, heart rate, and pulmonary artery and pulmonary capillary wedge pressures, without any significant changes in coronary perfusion pressure, cardiac output, stroke volume, and systemic or pulmonary vascular resistances. In some patients, ST-segment depression was less pronounced during TEA. Thus, during ischemic chest pain, TEA has beneficial effects on the major determinants of myocardial oxygen consumption, without jeopardizing coronary perfusion pressure. TEA may therefore favorably alter the oxygen supply/demand ratio within ischemic myocardial areas.     

Complications related to thoracic epidural analgesia: a prospective study in 1071 surgical patients

In a prospective study, the complications of 1071 patients scheduled for thoracic epidural catheterization for postoperative analgesia (TEA) were studied. All catheters were inserted preoperatively between segment Th 2/3 and Th 11/12 under local anesthesia. Balanced anesthesia with endotracheal intubation and TEA were combined. Postoperatively 389 patients (36.9%) were monitored on a normal surgical ward. Buprenorphine, 0.15 to 0.3 mg, and if needed bupivacaine 0.375% 3–5 ml h^-1 were given epidurally. Primary perforation of the dura occurred in 13 patients (1.23%). Radicular pain syndromes were observed in six patients (0.56%). In one patient (0.09%) respiratory depression was seen in close connection with the epidural administration of 0.3 mg buprenorphine. Although 116 patients (10.83%) showed one abnormal clotting parameter but no clinical signs of hemorrhage, there was no complication related to this group. No persisting neurological sequelae caused by the thoracic epidural catheters were found. In conclusion, continuous TEA with buprenorphine for postoperative pain relief after major abdominal surgery is a safe method without too high a risk of catheter-related or drug-induced complications, even on a normal surgical ward and when one clotting parameter is abnormal.