Jeong Seok Lee

Prophylactic effect of dexamethasone in reducing postoperative sore throat

Background This study was performed to compare the effectiveness of prophylactic dexamethasone and postintubation dexamethasone in reducing the incidence and severity of postoperative sore throat (POST). Methods This was a prospective, randomized, double-blind clinical trial. The study population consisted of 70 patients between 20 and 60 years old who were classified as American Society of Anesthesiologists I-II and were scheduled for elective laparoscopic cholecystectomy. The patients were divided randomly into two groups. Patients in the prophylactic and postintubation groups received intravenous injection of 10 mg of dexamethasone 30 min before or after tracheal intubation, respectively. The patients were interviewed 1, 6, and 24 h after the operation. The incidence and severity of POST were recorded. Results The severity scores of POST at 1 and 6 h after the operation were significantly lower in the prophylactic group than in the postintubation group. There were no significant differences in the incidence of POST during the 24 h after the operation between the two groups (22/32 in the prophylactic group vs. 27/34 in the postintubation group, P = 0.403). Conclusions Intravenous injection of 10 mg of dexamethasone was more effective in reducing the severity of POST when administered before tracheal intubation compared with after tracheal intubation.

Difference in Core temperature in response to propofol-remifentanil anesthesia and sevoflurane-remifentanil anesthesia

BACKGROUNDnHypothermia following the induction of anesthesia is caused by core to peripheral redistribution of body heat. It has been reported that propofol causes more severe hypothermia than sevoflurane by inhibiting thermoregulatory vasoconstriction during surgical procedures. Therefore, we evaluated the induction and maintenance of anesthesia with intravenous propofol to determine if it causes more core hypothermia than inhaled sevoflurane.nnnMETHODSnForty-five patients who underwent hysterectomy were divided into two groups randomly, a propofol-remifentanil (PR) anesthesia group and a sevoflurane-remifentanil (SR) anesthesia group. Each group was subjected to anesthetic induction with either 1.5 mg/kg propofol or inhalation of 5% sevoflurane, respectively. Anesthesia in the former group was maintained with propofol while it was maintained with sevoflurane in the latter group. Specifically, 6-10 mg/kg/hr propofol, 3 L/min medical air, 2 L/min O2, and 0.25 mg/kg/hr remifentanil were used in the PR group for maintenance, while 1.5 vol% sevoflurane, 3 L/min medical air, 2 L/min O2 and 0.25 mg/kg/hr remifentanil were used for maintenance in the SR group. We measured the core temperature 8 times, prior to induction and 10, 20, 30, 45, 60, 75 and 90 minutes after induction.nnnRESULTSnCore temperatures decreased in both the PR and SR group during surgical operation, but there was no significant difference between the two groups.nnnCONCLUSIONSnAnesthesia induced and maintained by propofol did not cause a greater degree of hypothermia than sevoflurane.

The effect of rocuronium on heart rate variability in diabetic patients

BACKGROUNDnClinically rocuronium, a muscle relaxant, has no significant inhibitory effect on the autonomic nervous system in the healthy population. However, there has been no study done on rocuronium in diabetic patients. Therefore, we used heart rate variability (HRV) as a biomarker to investigate cardiac autonomic function after rocuronium administration to diabetic patients.nnnMETHODSnIn 21 diabetic adult patients, heart rate (HR), mean arterial blood pressure (BP), low frequency (LF, 0.04-0.15 Hz) power, high frequency (HF, 0.15-0.4 Hz) power, LF/HF ratio, SD1 and SD2 in the Poincare plot before induction of anesthesia, and immediately before and after rocuronium administration were calculated and compared.nnnRESULTSnHR, mean BP, LF, LF/HF ratio and SD2 after rocuronium administration did not differ significantly from the measurements taken before rocuronium administration. HF and SD1 decreased significantly after rocuronium administration (P = 0.022, P = 0.019 respectively). Covariates such as age, gender, weight, duration of diabetes mellitus and hypertension did not alter the effect of rocuronium on the autonomic nervous system.nnnCONCLUSIONSnRocuronium produced a significant decrease in parasympathetic activity. Therefore, further study will be needed to determine whether vagal reduction caused by rocuronium could have potential to deteriorate hemodynamics in diabetic patients.