A Comparison of 0.1% and 0.2% Ropivacaine and Bupivacaine Combined with Morphine for Postoperative Patient-Controlled Epidural Analgesia After Major Abdominal Surgery

Does epidural morphine loading in addition to thoracic epidural analgesia benefit the postoperative management of morbidly obese patients undergoing open bariatric surgery? A pilot study

BACKGROUND

Insufficient data exist regarding postoperative thoracic epidural analgesia for morbidly obese patients undergoing open bariatric surgery. This study evaluated the effectiveness of morphine loading in a postoperative thoracic epidural analgesic regimen of patient-controlled epidural analgesia (PCEA) with levobupivacaine combined with continuously administered epidural morphine in this patient group.

METHODS

In this prospective randomized controlled trial, 48 superobese patients (body mass index of ≥ 50 kg/m(2)) undergoing open bariatric surgery were randomly allocated to three groups of 16 patients each. Postoperatively, all groups received a continuous epidural morphine infusion of 0.2 mg/h with 0.1 % levobupivacaine via PCEA. Group A did not receive intraoperative epidural morphine loading, while groups B and C received an intraoperative 1- and 2-mg morphine bolus, respectively. Levobupivacaine consumption via PCEA (primary outcome), pain scores at rest and on cough, the time to return of bowel function and ambulation, and arterial blood gas levels (secondary outcomes) were recorded.

RESULTS

The increase in perioperative morphine administration (groups B and C) led to a significantly prolonged return to normal bowel function and delayed ambulation (P<0.05 to 0.01, respectively), without an improvement in postoperative analgesia or a reduction in local anesthetic consumption. Although the prevalence of obstructive sleep apnea (OSA) was high in all groups, no respiratory depression was observed.

CONCLUSIONS

Thoracic PCEA with 0.1 % levobupivacaine combined with continuous epidural morphine administration of 0.2 mg/h without morphine loading is an effective postoperative analgesic regimen that provides adequate pain control, early ambulation, and early return of bowel function in superobese patients, particularly those with OSA.

Epidural anaesthesia with goal-directed administration of ropivacaine improves haemodynamic stability when combined with general anaesthesia in elderly patients undergoing major abdominal surgery

The use of epidural ropivacaine may result in significant haemodynamic fluctuations during combined epidural and general anaesthesia. We designed this study to investigate whether epidural anaesthesia with a goal-directed approach, when combined with general anaesthesia, improved haemodynamic stability in elderly patients undergoing major abdominal surgery. Seventy-five elderly patients undergoing major abdominal surgery were randomly and evenly assigned to one of three groups receiving intraoperative epidural anaesthesia with either ropivacaine 0.1% (Group 1), ropivacaine 0.375% (Group 2) or ropivacaine 0.375% for abdominal wall pain and ropivacaine 0.1% for visceral pain (Group 3). General anaesthesia was induced using a target-controlled infusion of combined propofol and remifentanil. The remifentanil target concentration was adjusted according to the mean arterial pressure and heart rate, and vasoactive agents were administered to maintain stable haemodynamics. The need for vasoactive drug administrations was 1.4 (standard deviation 0.9) in Group 3 (n=24), representing a significantly lower frequency of administration compared with Groups 1 (n=24) and 2 (n=24) (P <0.05 versus Group 1; P <0.01 versus Group 2). The total intraoperative dose of remifentanil was significantly greater in Group 1 (P <0.01 versus Group 2; P <0.05 versus Group 3) but did not differ significantly between Groups 2 and 3. Goal-directed epidural anaesthesia with different ropivacaine concentrations can improve haemodynamic stability when combined with general anaesthesia for elderly patients undergoing major abdominal surgery.

Epidural abscesses

Until recently epidural abscess was considered a rare, almost theoretical, complication of central nerve block, but anecdotal reports suggest that this is no longer the case. Thus a review of the risk factors, pathogenesis, clinical features and outcome of this condition is appropriate, the primary aim being to make recommendations on best anaesthetic practice to minimize the risk of this serious complication. A search of EMBASE(c), PUBMED(c) and MEDLINE(c) databases from 1966 to September 2004 was performed using several strategies, supplemented by reference list screening. Spontaneous epidural abscess is rare, accounting for 0.2-1.2 cases per 10,000 hospital admissions per year. Estimates of the incidence after central nerve block vary from 1:1,000 to 1:100,000. Risk factors (compromised immunity, spinal column disruption, source of infection) are present in the majority of patients, whether the condition is spontaneous or associated with central nerve block. Presentation is vague, fever and back pain usually preceding neurological deficit. Diagnosis requires a high index of suspicion and modern imaging techniques. Treatment involves early surgical drainage to prevent permanent deficit and high dose parenteral antibiotics chosen with bacteriological advice. Primary prevention depends on proper use of full aseptic precautions. Epidural abscess can be a catastrophic consequence of central nerve block. Early diagnosis will minimize permanent damage, but primary prevention should be the aim. There is a need for a large survey to indicate the true incidence to better inform the risk-benefit ratio for central nerve block.