Postoperative beneficial effects of esmolol in treated hypertensive patients undergoing laparoscopic cholecystectomy.

BACKGROUND: In an attempt to decrease haemodynamic instability and early postoperative complications such as nausea, vomiting, and pain, esmolol was added to the routine alfentanil infusion of patients with treated hypertension undergoing laparoscopic cholecystectomy. METHODS: Forty consecutive ASA class II patients with controlled hypertension about to undergo laparoscopic cholecystectomy were randomized into two groups: an esmolol group (Group E, n=20) was given a 1 mg kg(-1) bolus of esmolol and a placebo group (Group P, n=20) was given an identical volume of Ringer's lactate. The rate of esmolol infusion was adjusted to keep the heart rate between 65 and 75 beats min(-1) and was 5-10 microg kg(-1) min(-1) throughout the procedure. After operation, patients reported their nausea using a four-point scale. RESULTS: Esmolol had an opioid-sparing effect intraoperatively (P=0.001). Postoperative requirements for antiemetics were significantly less in the esmolol group, with no antiemetics given to eight patients. In the placebo group, however, all patients required at least one dose of antiemetic (P=0.007). The frequency of PONV did not correlate to the amounts of alfentanil, propofol, postoperative antiemetics consumed, or to female gender, non-smoking status, and history of PONV or motion sickness. Postoperative analgesic consumption in Group E was significantly lower than in Group P (P=0.012). CONCLUSIONS: Esmolol had an opioid-sparing effect in the intraoperative and immediate postoperative period in hypertensive patients undergoing laparoscopy. When combined with alfentanil, it was more effective than placebo in decreasing early PONV.

The effects of sevoflurane, isoflurane and desflurane on QT interval of the ECG.

BACKGROUND AND OBJECTIVE: To determine if there is any significant difference between the effects of desflurane, isoflurane and sevoflurane on the QT interval, QT dispersion, heart rate corrected QT interval and QTc dispersion of the electrocardiogram. METHODS: The study was conducted in a prospective, double blind and randomized manner in a teaching hospital. Ninety ASA I patients, aged 16-50 yr, undergoing general anaesthesia for noncardiac surgery were studied. RESULTS: There was no significant change in QT intervals during the study in any group (P > 0.05). QT dispersion in the sevoflurane group 49+/-14 ms vs. 37+/-10 ms; in the desflurane group 55+/-16 and 62+/-21 ms vs. 35+/-14 ms and in the isoflurane group 54+/-26 and 59+/-24 ms vs. 42+/-19 ms were significantly increased at 3 and 10 min after 1 MAC of steady end-tidal anaesthetic concentration compared with baseline values (P < 0.05). QTc values in the sevoflurane group were 444+/-24 and 435+/-2 1ms vs. 413+/-19 ms (P < 0.05), in the isoflurane group were 450+/-26 and 455+/-34 ms vs. 416+/-34 ms (P < 0.05), in the desflurane group were 450+/-26 and 455+/-34 ms vs. 416+/-34 ms (P < 0.05) at 3 and 10 min after reaching 1 MAC of anaesthetic concentration and significantly increased compared with baseline values. QTc dispersion increased significantly with sevoflurane 62+/-14 ms vs. 45+/-16 ms (P < 0.05); isoflurane 70+/-36 ms at 3 min and 75+/-36 ms at 10 min after reaching 1 MAC of anaesthetic concentration vs. 50+/-24 ms (P < 0.05); desflurane 67+/-25 ms at 3 min and 74+/-27 ms at 10 min after 1 MAC concentration vs. 41+/-22 ms (P < 0.05). CONCLUSION: Sevoflurane, isoflurane and desflurane all prolonged QTd, QTc and QTcd but there were no significant intergroup differences.

The effect of epidural anaesthesia and size of spinal needle on post-operative hearing loss.

Forty-five patients who were to undergo elective urological operations were evaluated. In the pre-operative period and on the third or fourth post-operative day audiometry was performed. Epidural anaesthesia was performed in 15 cases, spinal anaesthesia was performed in 15 cases with 25 G needles, and in 15 cases with 22 G needles. No statistically significant hearing loss was observed in the post-operative period compared to preoperative period in the epidural anaesthesia group. In the post-operative period, the hearing loss observed in the 25 G-spinal anaesthesia group was significantly (P < 0.01) less than that seen in the 22 G group. None of the patients had headache after spinal anaesthesia. It was concluded that pure tone audiometry is a more sensitive indicator of cerebrospinal fluid leakage than post-operative headache.