G. Isik

The effect of pre-anaesthetic administration of intravenous dexmedetomidine on postoperative pain in patients receiving patient-controlled morphine

Background and objective: This prospective, randomized, double‐blind, controlled study was designed to test the effect of pre‐anaesthetic administration of dexmedetomidine, given as a single intravenous (i.v.) dose, on postoperative pain scores and morphine consumption in patients receiving patient‐controlled morphine after abdominal surgery. Methods: Sixty patients were randomly allocated to receive dexmedetomidine (1 μg kg−1) or saline 10 min before induction of anaesthesia. Twenty minutes before the end of surgery, all patients received a standardized (0.1 mg kg−1) loading dose of morphine. They were then allowed to use a patient‐controlled analgesia (PCA) device giving bolus doses of morphine (0.02 mg kg−1). Pain, discomfort and sedation scores; cumulative morphine consumption; time to extubation; time to recovery; and any side‐effects were recorded after recovery and at 1, 2, 6, 12 and 24 h after the start of PCA. Results: The mean time to extubation at the end of anaesthesia and recovery time were similar in both groups. There were no significant differences between groups with regard to mean pain, discomfort, sedation and nausea scores. Cumulative morphine consumption was significantly lower in the dexmedetomidine group at 6, 12 and 24 h (P < 0.05). The incidence of side‐effects did not differ between the groups. Conclusions: A single i.v. dose of dexmedetomidine (1 μg kg−1) given 10 min before induction of anaesthesia significantly reduced postoperative morphine consumption at identical pain scores compared to control, but had no effect on postoperative recovery time.

The effect of adding intrathecal magnesium sulphate to bupivacaine–fentanyl spinal anaesthesia

Background:  The addition of intrathecal (IT) magnesium to spinal fentanyl prolongs the duration of spinal analgesia for vaginal delivery. In this prospective, randomized, double‐blind, controlled study, we investigated the effect of adding IT magnesium sulphate to bupivacaine–fentanyl spinal anaesthesia.

Comparison of caudal morphine and tramadol for postoperative pain control in children undergoing inguinal herniorrhaphy.

Objectives: We compared the quality and duration of analgesia, the effect on perioperative sevoflurane requirement after a single, presurgical caudal block with either tramadol or morphine in children undergoing inguinal herniorrhaphy. Our study was also designed to evaluate the preemptive analgesic efficacy of morphine administered caudally in children.

Comparative study of the antiemetic efficacy of ondansetron, propofol and midazolam in the early postoperative period

Background and objective: To compare the antiemetic efficacy of ondansetron with two different hypnotic drugs (propofol 15 mg, midazolam 1 and 2 mg) for the treatment of established postoperative nausea and vomiting (PONV). Methods: Four-hundred-and-fifty-three patients scheduled for elective gynaecological or abdominal surgery were enrolled. One-hundred-and-twenty patients (26%) experienced postoperative emesis, and when nausea scores reached 2 or greater on a five-point scale, they were randomized to receive intravenously: propofol 15 mg (1.5 mL) in Group P, midazolam 1 mg in Group M1, midazolam 2 mg in Group M2 and ondansetron 4 mg in Group O. Results: Four patients (13.3%) in Group P, 13 patients (43.3%) in Group M1, five patients (16.6%) in Group M2 and one patient (3.3%) in Group O required a second dose of the study drug. After administration of the study drugs, nausea scores were significantly lower in all groups than before these drugs were given. No patient had a sedation score over 3 (the patients remained awake and/or responded to verbal contact). The sedative effects of midazolam and propofol lasted for a much shorter time than the antiemetic effects of these drugs. Conclusions: Propofol and midazolam used in subhypnotic doses were as effective as ondansetron in treating PONV in patients undergoing abdominal or gynaecological surgery without untoward sedative or cardiovascular effects.

Postoperative pain management with intravenous patient-controlled morphine: comparison of the effect of adding magnesium or ketamine.

Background and objective: This double‐blind randomized study tested whether the addition of magnesium or ketamine to morphine for intravenous patient‐controlled analgesia resulted in improved analgesic efficacy and lower pain scores compared with morphine patient‐controlled analgesia alone after major abdominal surgery. Methods: Ninety patients (3 × 30) were randomly allocated to receive either morphine 0.4 mg mL−1 (Group M) by patient‐controlled analgesia, morphine 0.4 mg mL−1 + MgSO4 30 mg mL−1 (Group MM) or morphine 0.4 mg mL−1 + ketamine 1 mg mL−1 (Group MK). Postoperative analgesia was started when the verbal rating scale was ≥2. Patients were first given a standardized loading dose (0.05 mg kg−1) of the study solution. They were then allowed to use bolus doses of this solution (0.0125 mg kg−1 every 20 min without time limit). Discomfort, sedation, pain scores, cumulative morphine consumption and adverse effects were recorded up to 24 h after the start of the patient‐controlled analgesia. Results: The level of discomfort, level of sedation and verbal rating scores decreased significantly with time in all groups (P < 0.05). Both verbal rating and discomfort scores were significantly lower in Groups MM and MK at 15, 30 and 60 min compared with Group M (P < 0.001). Cumulative morphine consumption after 12 and 24 h was significantly higher in Group M alone (median 26 and 49 mg, respectively) compared with Group MM (24.2 and 45.7 mg) and Group MK (24.4 and 46.5 mg). Conclusions: In the immediate postoperative period, the addition of magnesium or ketamine to morphine for intravenous patient‐controlled analgesia led to a significantly lower consumption of morphine. However, these differences are unlikely to be of any clinical relevance.

Remifentanil produces vasorelaxation in isolated rat thoracic aorta strips.

Background: Remifentanil can cause transient instability in hemodynamic variables. However this change may not be solely the result of autonomic or central nervous system inhibition or of centrally mediated vagal stimulation. In this study, the aim was to examine the direct effects of remifentanil on isolated thoracic aorta strips in vitro.

Comparison of intrathecal magnesium, fentanyl, or placebo combined with bupivacaine 0.5% for parturients undergoing elective cesarean delivery

Background: Intrathecal (i.t.) administration of magnesium has been reported to potentiate opioid antinociception in rats and humans. In this prospective, randomized, double‐blind, study, we investigated the sensory, motor, and analgesic block characteristics of i.t. magnesium 50 mg compared with fentanyl 25 μg and saline when added to 0.5% bupivacaine (10 mg).

Comparison of caudal ropivacaine, ropivacaine plus ketamine and ropivacaine plus tramadol administration for postoperative analgesia in children

Background : The aim of this study was to compare the effect of single‐dose caudal ropivacaine, ropivacaine plus ketamine and ropivacaine plus tramadol in children for postoperative pain management.

A comparison of single dose caudal tramadol, tramadol plus bupivacaine and bupivacaine administration for postoperative analgesia in children

Background: Our aim was to compare the effect of single dose caudal tramadol, tramadol plus bupivacaine and bupivacaine on the management of postoperative pain in children.

The influence of epidural volume extension on spinal block with hyperbaric or plain bupivacaine for Caesarean delivery.

Background and objective: Epidural volume extension via a combined spinal‐epidural is the enhancement of a small‐dose intrathecal block by an epidural injection of physiological saline solution. We evaluated the effect of epidural volume extension on the combined spinal‐epidural technique of providing spinal anaesthesia for Caesarean section with hyperbaric or plain 0.5% bupivacaine. Methods: Patients (n = 240) with height >163 cm received 9 mg and patients <163 cm received 8 mg of bupivacaine. Each study drug was combined with 20 &mgr;g fentanyl. Using the combined spinal‐epidural technique, Group A (n = 60) received hyperbaric bupivacaine, and Group B (n = 60) received hyperbaric bupivacaine and 10 mL saline epidurally 5 min after subarachnoid injection. Group C (n = 60) received plain bupivacaine and Group D (n = 60) received plain bupivacaine and 10 mL saline epidurally 5 min after subarachnoid injection. An anaesthetist blinded to the anaesthetic solution injected examined the level of analgesia by the pinprick method and motor block with the modified Bromage scale for 30 min after subarachnoid injection, during the intraoperative period and subsequently every 15 min for 135 min during the recovery period. Results: Time to reach a sensory block at T4 was significantly shorter in Groups C and D than in Groups A (P = 0.003 and 0.017) and B (P = 0.006 and 0.048), respectively. During the intraoperative period, sensory block levels were significantly higher in Group C than in Group A. Recovery was similar in all groups; only onset was faster in Groups C and D. Conclusion: There was no effect of epidural volume extension on the profile of spinal anaesthesia with the combined spinal‐epidural technique for Caesarean section using hyperbaric or plain bupivacaine.