Double-blind comparison of intrapleural saline and 0.25% bupivacaine for ipsilateral shoulder pain after thoracotomy in patients receiving thoracic epidural analgesia.

BACKGROUND: The aim of this prospective double-blind randomized placebo-controlled study was to investigate the effect of intrapleural bupivacaine on ipsilateral post-thoracotomy shoulder pain in patients receiving thoracic epidural analgesia. METHODS: Of the 68 patients recruited to the study, 41(60%) developed ipsilateral shoulder pain within 2 h of surgery. These patients were randomly assigned to receive either 40 ml of intrapleural bupivacaine 0.25% with epinephrine 1:200 000 or 40 ml of intrapleural saline. The study solution was injected into the tube of a basal drain that had been clamped distal to the site of administration. Shoulder pain at rest and on coughing was assessed using a visual analogue scale (VAS) and an observer verbal rating score (OVRS) immediately before and 30 min, 1 h, 2 h, 3 h and 4 h after intrapleural bupivacaine/saline. The total volume of epidural solution administered was recorded. RESULTS: Thirty-nine patients completed the study and were included in the analysis. There were no significant differences in baseline characteristics between the two groups. There were no significant differences between groups for VAS or OVRS pain scores at rest or with cough at any of the six assessment times. The total volumes of epidural solution administered to the bupivacaine and saline groups were 56 ml and 48 ml, respectively. This difference was not significant. CONCLUSION: Intrapleural administration of 40 ml of bupivacaine 0.25% does not provide effective pain relief for ipsilateral post-thoracotomy shoulder pain.

A prospective, randomised, single-blind pilot study to determine the effect of anaesthetic technique on troponin T release after off-pump coronary artery surgery.

Ischaemic damage to the myocardium inevitably occurs during coronary artery surgery. However, the extent of the damage may be influenced by the anaesthetic technique used. The most sensitive and reliable marker of myocardial damage is currently thought to be troponin T. We conducted a prospective, randomised, single-blind pilot study to determine the baseline values of troponin T release after off-pump coronary artery bypass surgery in 30 patients randomly allocated to receive either propofol, isoflurane or isoflurane and high thoracic epidural analgesia. All other treatment was standardised. Patients undergoing emergency surgery and those with unstable angina were excluded. Blood samples were taken at 0, 3, 6, 12, 24 and 48 h after surgery for troponin T analysis. Mean troponin T levels at 24 h were not significantly different between the groups (p = 0.41). These data allows appropriate power calculations for further, large-scale studies to determine the anaesthetic technique that provides optimal myocardial protection.

Optimal concentration of epidural fentanyl in bupivacaine 0.1% after thoracotomy.

BACKGROUND: The aim of this prospective, double-blind, randomized controlled trial was to investigate the analgesic and adverse effects of three commonly used concentrations of thoracic epidural fentanyl with bupivacaine in patients undergoing thoracotomy for lung resection. METHODS: We studied 99 patients who were randomized to receive fentanyl 2 microg ml(-1) (group 2), fentanyl 5 microg ml(-1) (group 5) and fentanyl 10 microg ml(-1) (group 10) in bupivacaine 0.1% via a thoracic epidural. Postoperatively, pain on coughing was assessed using a visual analogue scale (VAS) and an observer verbal rating score (OVRS) at 2, 8, 16 and 24 h. At the same times, sedation, pruritus and nausea were assessed. RESULTS: Of 29, 28 and 32 patients who completed the study in groups 2, 5 and 10 respectively, there was no significant difference in baseline characteristics between the three groups. The number of patients with episodes of unsatisfactory pain, i.e. VAS scores >30 mm and OVRS >1, at each of the four assessments postoperatively was significantly (P<0.01) higher in group 2 than in groups 5 and 10. In group 10, 16 patients had sedation scores >1 compared with 10 each in groups 2 and 5. In addition, 19 patients in group 10 experienced pruritus compared with 12 each, in groups 2 and 5. These differences were not significant. Nausea was not significantly different between the three groups. CONCLUSION: We conclude that thoracic epidural fentanyl 5 microg ml(-1) with bupivacaine 0.1% provides the optimum balance between pain relief and side effects following thoracotomy.

Gastric emptying in post-thoracotomy patients receiving a thoracic fentanyl-bupivacaine epidural infusion.

BACKGROUND AND OBJECTIVE: The effect of anaesthesia and surgery on gastric emptying is not constant, and this has not been previously studied in patients undergoing thoracotomy for lung resection with a bupivacaine-fentanyl epidural infusion for analgesia. There are important implications in this group of patients with regards to the recommencement of important oral medication as well as the risks of aspiration of gastric contents. The study examined gastric emptying in these patients until the second postoperative day. METHODS: In a prospective repeated measures study, the effect of fentanyl-bupivacaine epidural analgesia at the mid-thoracic level on gastric emptying was assessed in 11 patients undergoing thoracotomy for lung resection. Gastric emptying was measured using a paracetamol absorption technique. Patients acted as their preoperative controls and were assessed 4 h postoperatively and on the second postoperative day. RESULTS: The mean (SEM) maximum plasma paracetamol concentration was 204.6 (20.4) micromol L(-1) before operation, 61 (9.5) micromol L(-1) 4 h postoperatively and 114.3 (22.6) micromol L(-1) on the second postoperative day. Mean (SEM) paracetamol absorption at 120 min was 15,638 (1441) micromol min L(-1) preoperatively, 5731 (821) micromol min L(-1) 4 h postoperatively and 9325 (1759) micromol min L(-1) on the second postoperative day. Postoperative values were significantly (P < 0.005) less than the preoperative values. CONCLUSIONS: After thoracotomy, gastric emptying was delayed until at least the second postoperative day in patients receiving mid-thoracic fentanyl-bupivacaine epidural analgesia.