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Background: Since in caesarean operations skin incision to delivery time is very short, induction agent could be still effective on BIS level till the time of delivery. Therefore this study was designed to analyze the effect on maintaining adequate bispectral index levels till delivery of neonate of propofol and thiopental as an induction agent for caesarean section., Methods: Eighty two patients undergoing caesarean section were allocated into two groups. In the group T anesthesia induction was performed with thiopental (5 mg/kg) and in the group P with propofol (2.5 mg/kg). Anesthesia was maintained with sevoflurane. Heart rates, blood pressures and BIS values during significant events of surgery and anesthesia till delivery, durations of surgery, induction to skin incision and to delivery and Apgar scores were recorded. For statistical analysis T-test was used for comparison of means of independent samples., Results: The groups were comparable with respect to age, weight and gestational age. The patients in the group P had significantly lower levels of bispectral index values during uterus incision; 40.6 vs. 59.5 (p = 0.019) and delivery; 41 vs. 62.9 (p = 0.018)., Conclusion: Anesthesia induction with propofol in a dose of 2.5 mg/kg maintains lower levels of heart rate, blood pressure and BIS till delivery when compared with thiopental in a dose of 5 mg/kg. There is no financial support taken from any kind of company or person. There are no financial relationships between authors and commercial interests with a vested interest in the outcome of study.

Background: The time at which children should resume oral intake after surgery is controversial. No information has been published about the relationship between postoperative vomiting and the temperature of the fluid ingested. This study was designed to analyze the effect on postoperative vomiting of the timing and temperature of the fluids ingested in the first oral intake., Methods:   Two hundred and thirty-seven male children aged 2-7 years, scheduled for correction of inguinal hernia or undescended testis under general anesthesia and were allocated into four groups. The patients in groups C1 and C2 received clear fluids at room temperature or at body temperature, respectively, 2 h after emergence. The patients in groups E1 and E2 received clear fluids at room temperature or at body temperature, respectively, 1 h after emergence. Vomiting was assessed at intervals of 30 min for 6 h postoperatively, starting from 10 min after emergence., Results:   The incidence of vomiting was higher in groups C1 (25%) (P = 0.016) and E1 (26.7%) (P = 0.011) than in groups C2 (6.9%) and E2 (10.2%). The incidence was found to be increased significantly 40 min after oral intake in groups C1 (P = 0.012) and E1 (P = 0.010) compared with earlier measurements in the same groups., Conclusion:   A first oral intake in children 1 h after anesthesia for minor surgery seems not to increase the incidence of vomiting as long as the ingested fluid is at body temperature., (© 2011 Blackwell Publishing Ltd.)

Objective: To investigate the combination effect of low dose fentanyl and subhypnotic dose of propofol on emergence agitation in children receiving sevoflurane for adenotonsillectomy procedure., Methods: After ethical approval, a prospective, randomized, clinical study was performed in Saad Specialist Hospital, Al-Khobar, Kingdom of Saudi Arabia in 2007-2008. One hundred and twenty children in physical status of I according to the American Society of Anesthesiologists, aged 2-6 years, scheduled for adentonsillectomy under general anesthesia were allocated into 3 groups randomly. Anesthesia was induced and maintained by sevoflurane in all groups. Children received 0.1 ml.kg-1 normal saline at the end of surgery in group C (n=40), 1.5 mcg.kg-1 fentanyl during induction, and 0.1 ml.kg-1 normal saline at the end of surgery in group F (n=40), and 1.5 mcg.kg-1 fentanyl during induction and 1 mg.kg-1 propofol at the end of surgery in group FP (n=40). Postoperative agitation was recorded, if any, for the first postoperative hour., Results: Three groups were comparable with regard to demographic data. Twenty-one patients (53%) in the control group, 14 patients (35%) in group F and 7 (18%) patients in group FP experienced postoperative agitation., Conclusion: The combination of low dose fentanyl before surgery and propofol at the end of surgery decreases the incidence and level of emergence agitation in children after adenotonsillectomy procedure under sevoflurane anesthesia.

Background: Obese patients may be sensitive to the respiratory depressant effect of opioid analgesics. Alternative methods for analgesia may be beneficial for management of bariatric surgery. We evaluated the effect of dexmedetomidine on anesthetic requirements during surgery, hemodynamic, recovery profile and morphine use in the postoperative period., Methods: Eighty adult patients scheduled for elective laparoscopic Roux-en-Y gastric bypass surgery were randomly assigned to one of two study groups; Group D (40 patients) received dexmedetomidine (0.8-microg/kg bolus, 0,4 microg kg(-1) h) and Group P (40 patients) received normal saline (placebo) in the same volume and rate. Intraoperative and postoperative mean blood pressure and heart rate were recorded. The total amount of intraoperative fentanyl and propofol required to maintain anesthesia were measured. Recovery profile, pain score and total amount of morphine used via patient controlled analgesia (PCA) were assessed., Results: During surgery, dexmedetomidine decreased the total amount of intraoperative fentanyl and propofol required for maintenance of anesthesia compared to placebo. Patients who received dexmedetomidine showed significant decrease of intraoperative and postoperative mean blood pressure, heart rate. In the postoperative period, dexmedetomidine decreased pain scores and PCA morphine use significantly and showed better recovery profile as compared to the placebo Group. There was no difference in the incidence of postoperative nausea and vomiting (PONV) between both groups., Conclusion: The intraoperative infusion of dexmedetomidine decreased the total amount of propofol and fentanyl required to maintain anesthesia, offered better control of intraoperative and postoperative hemodynamics, decreased postoperative pain level, decreased the total amount of morphine used and showed better recovery profile compared with placebo.

We have compared the reversal characteristics of mivacurium after administration of an edrophonium-plasma cholinesterase (PCHE) combination with that produced by each antagonist alone. Forty ASA I adults were given mivacurium 0.15 mg kg-1 during fentanyl-thiopentone-nitrous oxide-isoflurane anaesthesia. TOF stimulation was applied to the ulnar nerve every 12 s, and the force of contraction of the adductor pollicis muscle was recorded. When spontaneous recovery of first twitch height (T1) reached 10% of its initial control value, patients were allocated randomly to one of four groups (n = 10 in each). Neuromuscular function in patients in group 1 (control group) was allowed to recover spontaneously. Patients in groups 2-4, respectively, received edrophonium 1 mg kg-1 (group ED), exogenous PCHE equivalent to activity present in 25 ml kg-1 of human plasma (group PCHE) or edrophonium 1 mg kg-1 with exogenous human PCHE equivalent to the activity present in 25 ml kg-1 of human plasma (combination group). The time to attain a TOF ratio of 0.75 in the combination group was 4.6 (SD 0.9) min. This was shorter (P < 0.01) than that observed in patients in the control (16.8 (3.3) min), ED (8.9 (3.6) min) and PCHE (9.3 (1.6) min) groups. There was no difference in recovery indices between groups ED and PCHE. We have demonstrated that the edrophonium-PCHE combination significantly accelerated recovery of mivacurium-induced block compared with that observed with the use of individual antagonists.

Background: Mivacurium, a nondepolarizing muscle relaxant, is hydrolyzed by butyrylcholinesterase. The use of butyrylcholinesterase for antagonism of profound mivacurium-induced blockade has not been studied in humans. In part 1 of this two-part study, the authors examined the relationship between the posttetanic count (PTC) and recovery from profound mivacurium-induced blockade. In part 2, an attempt was made to antagonize a quantified level of profound mivacurium-induced blockade using either butyrylcholinesterase, edrophonium, or neostigmine., Methods: Eighty-seven ASA physical status 1 or 2 adult patients were given 0.15 mg.kg-1 mivacurium during fentanyl-thiopental-nitrous oxide-isoflurane anesthesia. They were randomly assigned to eight groups. Neuromuscular function was monitored by recording the mechanomyographic response of the adductor pollicis to PTC and train-of-four (TOF) stimulation in all patients except those in group 1 where the TOF was the only pattern used. In part 1, neuromuscular function was allowed to recover spontaneously in ten patients (group 1; control-TOF) until TOF ratio (the amplitude of the fourth evoked response as a fraction of the first evoked response T4/T1) had reached 0.75. The temporal relationship between PTC and the first reaction to TOF stimulation was determined in another 31 patients, and neuromuscular function in 10 of these patients was allowed to recover spontaneously until TOF ratio had reached 0.75. The temporal relationship between PTC and the first reaction to TOF stimulation was determined in another 21 patients, and neuromuscular function in 10 of these patients was allowed to recover spontaneously, until TOF ratio had reached 0.75 (group 2; control-PTC). In part 2, the antagonism of mivacurium-induced profound (PTC > or = 1; groups 3-6) and 90% block (groups 7-8) of twitch height were investigated in another 56 patients. Groups 3 and 7 received neostigmine 0.06 mg.kg-1 whereas groups 4 and 8 received edrophonium 1 mg.kg-1, respectively. Groups 5 and 6 received exogenous human butyrylcholinesterase equivalent to activity present in 25 or 70 ml.kg-1 of human plasma, respectively., Results: Neither butyrylcholinesterase nor edrophonium shortened the times from first PTC response to TOF = 0.75 compared to group 2. Neostigmine resulted in prolongation of recovery time. There was a linear relationship (r = -0.80; P = 0.00001) between PTC and time of onset of TOF response., Conclusions: There appears to be no clinical advantage in attempting to antagonize profound mivacurium-induced neuromuscular blockade.

We have examined the effects of different benzyl-isoquinolinium and steroidal neuromuscular blocking compounds on plasma concentrations of histamine, heart rate and arterial pressure in surgical patients. A single, rapid (5-s) bolus of mivacurium 0.2 mg kg-1, atracurium 0.6 mg kg-1, tubocurarine 0.5 mg kg-1, vecuronium 0.1 mg kg-1 or rocuronium 0.6 mg kg-1 was administered to 75 patients (n = 15 in each group). Anaesthesia was induced with thiopentone 6 mg kg-1 i.v. and maintained with isoflurane and 70% nitrous oxide in oxygen. Venous blood samples were obtained before induction, 1 min after thiopentone and 1, 3 and 5 min after administration of the neuromuscular blocking drug. Mivacurium, atracurium and tubocurarine caused 370%, 234% and 252% increases in plasma histamine concentrations at 1 min, respectively. Corresponding values at 3 min were 223%, 148% and 157%, respectively. These changes were significant (P < 0.01) at 1 and 3 min. In contrast, the rocuronium and vecuronium groups had no significant changes in either plasma histamine concentrations or haemodynamic variables.

We have determined the relative potency of rocuronium, pancuronium, pipecuronium and vecuronium, and examined the nature of the interaction of rocuronium with the other three steroidal neuromuscular blocking drugs. We studied the dose-response relationships of each drug and their combination with rocuronium in 200 ASA I or II patients during propofol-fentanyl-nitrous oxide-oxygen anaesthesia. Neuromuscular block was recorded as the evoked thenar mechanomyographic response to single twitch stimulation of the ulnar nerve at 10-s intervals. The dose-response curves were determined by probit analysis. Isobolographic and algebraic (fractional) analyses were used to assess the combined effect of equipotent doses of rocuronium and vecuronium, pipecuronium or pancuronium and to define the type of interaction between these drugs. The isobolograms were constructed by plotting single-drug ED50 points on the dose co-ordinates, and a combined ED50 point in the dose field. The calculated doses producing 50% depression (ED50) of the twitch height for rocuronium, pancuronium, pipecuronium and vecuronium were 144.8 (95% confidence intervals 140.4-149.3), 32.4 (31.7-32.9), 27.1 (26.5-27.6) and 23.7 (22.7-24.8) micrograms kg-1, respectively. Corresponding doses producing 95% depression (ED95) of twitch height were, respectively, 322.1 (307.5-337.3), 58.1 (56.2-60.1), 48.7 (46.9-50.5) and 39.9 (38.4-41.4) micrograms kg-1. Based on the estimate of ED50, the relative potency was 1:4.5:5.4:6, respectively. The interaction between rocuronium and vecuronium, pipecuronium or pancuronium was found to be additive.

The pediatric laryngeal mask airway (LMA) is a scale-down version of the adult form, and no direct postmortem specimen work has been performed so far. There are several anatomical differences between pediatric and adult airways, and hence, the scale-down version of the adult LMA is not necessarily water-tight in pediatric patients. We performed a prospective study to assess airway protection by the LMA in pediatric patients, using methylence blue (injected in the pharynx outside the LMA) and the fibreoptic bronchoscope to view the inside of the mask, to detect any leakage of the dye. Fifty Patients (40 boys and 10 girls) aged 1-10 years (mean 4.5 yr) were studied. All patients underwent surgery below the level of the umbilicus, under light general anesthesia combined with caudal epidural block. All patients were allowed to breath spontaneously over an Ayre's T-piece. Dye staining of the inside of the mask was detected in 5 patients (10%). The esophageal opening was visualized within the mask in 3 patients (6%). No serious complications occurred in any of our patients.