The effects of dexmedetomidine on hemodynamic responses to tracheal ntubation in hypertensive patients: A comparison with esmolol and sufentanyl.

BACKGROUND: Hypertension and tachycardia caused by tracheal intubation can be detrimental in hypertensive patients. This study was conducted in order to compare the effects of dexmedetomidine on hemodynamic response to tracheal intubation in hypertensive patients with esmolol and sufentanyl. METHODS: Sixty hypertensive patients scheduled for noncardiac surgery under general anesthesia were randomly assigned to receive one of the three drugs before induction of anesthesia. Groups I, II, and III respectively received esmolol (100 mg) dexmedetomidine (1 µg/kg) and sufentanyl (0.25 µg/kg). Heart Rate (HR), systolic (SAP) and diastolic (DAP) arterial pressures were recorded before drug administration (baseline; T1), after drug administration (T2), after induction of anesthesia (T3), immediately after intubation (T4) and 3, 5 and 10 minutes after intubation (T5, T6, and T7, respectively). The mean percentage variations from T1 to T4 were calculated for all variables (HR, SAP and DAP). Thiopental dose, onset time of vecuronium and intubation time were also assessed. RESULTS: No differences were observed between the three groups regarding demographic data (p > 0.05). Median thiopental dose was significantly lower in Group II (325 mg; range: 250-500) compared to Group I (425 mg; range: 325-500; p < 0.01) and Group III (375 mg; range: 275-500; p = 0.02). The onset time of vecuronium was longest in Group I (245.2 ± 63 s vs. 193.9 ± 46.6 s and 205.5 ± 43.5 s; p < 0.01 and p < 0.05). In Group I, HR significantly decreased after drug administration compared to baseline (83.8 ± 20.4 vs. 71.7 ± 14.8; p = 0.002). Compared to the baseline (90.4 ± 8.4), DAP decreased after induction and remained below baseline values at T5, T6 and T7 (71.3 ± 12.8, 76.2 ± 10.7, 68.9 ± 10.8 and 62.1 ± 8.7, respectively; p < 0.05) in Group II. According to the mean percentage variation, a significant reduction in HR was assessed in Group II compared to Group III (-13.4 ± 17.6% vs. 11.0 ± 27.8%; p = 0.003). Increment in SAP was significant in Group I when compared to Group II (9.8 ± 20.9% vs. -9.2 ± 20.2%; p < 0.05). Increment in DAP in Group III was significant compared to Group II (0.07 ± 19.8 vs. 24.5 ± 39.1; p < 0.05). CONCLUSIONS: In hypertensive patients, administration of dexmedetomidine before anesthesia induction blunts the hemodynamic response to tracheal intubation and reduces the thiopental dose.

Preventive effect of dexmedetomidine in ischemia-reperfusion injury.

BACKGROUND: The aim of this study was to evaluate the effects of dexmedetomidine on ischemia-reperfusion injury of epigastric island flaps of rats. METHODS: Eighty Wistar rats were divided into 4 groups. After the flap elevation, in group 1, the flaps were sutured back without ischemic insult. Groups 2, 3, and 4 were exposed to ischemia for 12 hours. In groups 1 and 2, saline, in group 3, 10 µg/kg dexmedetomidine, and in group 4, 30 µg/kg dexmedetomidine were administered i.p. 45 minutes before I/R periods. Each group was subdivided further into 2 equal groups (a and b). Tissue samples of groups 1a, 2a, 3a, and 4a were obtained 12 hours after the reperfusion, and those of groups 1b, 2b, 3b, and 4b were obtained after 7 days. The necrotic areas were also calculated. Nitric oxide, malondialdehyde (MDA), and myeloperoxidase (MPO) activity were assessed in the tissue samples. RESULTS: Nitric oxide, MDA, and MPO activity levels in group 2a were significantly higher those in group 1a (P < 0.05). The levels in groups 3a and 4a were lower than those in group 2a (P < 0.05). Nitric oxide, MDA, and MPO activity levels were significantly higher in group 2b compared with group 1b (P < 0.05). The levels were lower in Groups 3b and 4b compared with group 2b (P < 0.05). Flap necrosis area was significantly lower in groups 3b and 4b than that in group 2b (P < 0.05). CONCLUSIONS: We conclude that administering dexmedetomidine before I/R periods can reduce ischemia-reperfusion injury of flaps, and it has a beneficial effect on flap survival.

The efficacy of intravenous paracetamol versus tramadol for postoperative analgesia after adenotonsillectomy in children.

STUDY OBJECTIVE: To evaluate the efficacy and the quality of recovery with intravenous (IV) paracetamol versus tramadol for postoperative analgesia after adenotonsillectomy in children. DESIGN: Prospective, randomized, double-blinded clinical trial. SETTING: Operating room and Postanesthesia Care Unit (PACU) of a university-affiliated hospital. PATIENTS: 64 ASA physical status I and II children, aged 6 to 16 years, scheduled for adenotonsillectomy. INTERVENTIONS: All patients were premedicated with oral midazolam 0.5 mg/kg 30 minutes before surgery. Patients were randomized to two groups following induction of general anesthesia. The paracetamol group (n = 32) received 15 mg/kg of IV paracetamol and the tramadol group (n = 32) received 1.0 mg/kg of IV tramadol. MEASUREMENTS: Modified Hannallah pain scores, emergence agitation, Aldrete scores, sedation scores, time to first administration of analgesic, heart rate, and mean arterial blood pressure were recorded for each patient. Data were recorded every 5 minutes for the first 30 minutes and every 10 minutes for the remaining 30 minutes in the PACU, then at 2, 3, 4, 5, 6, 8, 12, and 24 hours in the ward. The frequency of postoperative nausea and vomiting also was noted. Satisfaction of parents and nurses was determined on a 4-point scale at the end of the study. MAIN RESULTS: No significant demographic differences between groups were noted. No statistically significant difference was found in postoperative pain scores in either group. Agitation scores, Aldrete scores, sedation scores, and number of patients who received rescue analgesia and time to administration of rescue analgesia were similar in both groups. CONCLUSIONS: The IV formulation of paracetamol was associated with similar analgesic properties and early recovery to that of IV tramadol after adenotonsillectomy in children.

The efficacy of ilioinguinal and iliohypogastric nerve block for postoperative pain after caesarean section.

BACKGROUND: The effect of ilioinguinal and iliohypogastric (II-IH) nerve block on postoperative pain is well documented when performed before Caesarean section (CS) but the efficacy remains unclear when performed after the surgical procedure. The aim of this study is to investigate the effect of II-IH nerve block on postoperative pain and analgesic consumption in patients when performed after CS. METHODS: Sixty ASA I- II patients, scheduled for elective CS were included in the study. After general anaesthesia, patients were allocated into 2 groups randomly. In group I bilateral II-IH block has been performed after the skin closure, with 10 ml of 0.5% ropivacaine on each side. In group II sham block had been performed. For postoperative analgesia all patients received tramadol via i.v patient controlled analgesia. Visual analogue scale (VAS) scored tramadol consumption and side effects. RESULTS: The mean VAS scores in II-IH block group were significantly lower than in sham block group at 6(th), 8(th), 12(th), 24(th) hours at rest (p < 0.05) and at 6(th), 8(th) hours with movement (p < 0.05). Tramadol usage in II-IH block group was significantly less than in sham block group at all estimated time intervals (p < 0.05). Total tramadol consumption was 331 ± 82 mg in II-IH block group and 622 ± 107 mg in sham block group (p < 0.05). CONCLUSIONS: It was observed that II-IH nerve block when performed after the surgery may reduce analgesic consumption after CS.

Bilateral extraoral, infraorbital nerve block for postoperative pain relief after cleft lip repair in pediatric patients: a randomized, double-blind controlled study.

The objective of this study was to evaluate the effectiveness of bilateral extraoral infraorbital nerve block with 0.25% bupivacaine administered at the end of surgery in postoperative pain relief after cleft lip repair. Forty ASA I-II children were randomly divided into 2 groups. Group I received 1.5 mL 0.25% bupivacaine and group II received 1.5 mL saline. FLACC scores of the patients in the recovery room in group I were 4 times less than in group II (P = 0.001) and in the first 4 hours postoperatively were apparently less in group I (P = 0.001). Mean time to first paracetamol requirement was longer in group I (P = 0.001). Total paracetamol consumption was lower in group I (P = 0.001). None of the patients required rescue tramadol in group I, whereas all patients in group II needed. In group I, parent satisfaction scores were higher (P = 0.001). Vomiting incidence was higher in group II (P = 0.028). Bilateral extraoral, infraorbital nerve block administered at the end of surgery provides satisfactory analgesia with high parental satisfaction and lower complication rates and reduces rescue analgesic consumption in patients undergoing repair of cleft lip.