CAN J ANESTH 55: 1 www.cja-jca.org Januar y, 2008Purpose: To determine whether a functional difference exists between the size 2 laryngeal mask airway (LMA)-Classic™ (CLMA) and LMA-Proseal™ (PLMA) in anesthetized children who have received neuromuscular blockade. Airway leak during intermittent positive pressure ventilation (IPPV) and adequacy of fibreoptic laryngeal view were the primary study outcomes. Methods:A randomized, controlled, single-blinded study of 51 ASA I or II children weighing 10-20 kg was undertaken. The anesthetic technique was standardized. Following insertion of the LMA and cuff inflation to 60 cm H 2 O, we measured oropharyngeal leak pressure and gastric insufflation and leak fraction during IPPV, and evaluated the adequacy of fibreoptic view.Results: Oropharyngeal leak pressure measured by neck auscultation was higher for the PLMA compared to the CLMA (23.7 vs 16.5 cm H 2 O, P = 0.009) but, when measured by the inspiratory hold maneuver was not significantly different (24.8 vs 20.3 cm H 2 O, respectively, P = 0.217). Leak fraction values were similar for the CLMA and the PLMA (21.2%. vs 13.3%, respectively, P = 0.473). A satisfactory view of the larynx was obtained more frequently in the PLMA group (21/25 vs 10/25, P = 0.003). Gastric insufflation during leak determination was more common with the CLMA (12/26 vs 2/25 CLMA vs PLMA, respectively, P = 0.006). Conclusion:In children undergoing IPPV with neuromuscular blockade, the size 2 PLMA is associated with a higher leak pressure by auscultation and less gastric insufflation compared to the CLMA. Leak pressures assessed by manometric stability are similar with these two devices. The improved fibreoptic view of the larynx through the PLMA may be advantageous for bronchoscopy. CLMA (23,7 vs 16,5 cm H 2 O, P = 0,009) ; toutefois, lorsque celle-ci a été mesurée par manoeuvre de retenue respiratoire, il n'y a pas eu de différence significative (24,8 vs 20,3 cm H 2 O, respectivement, P = 0,217). Les valeurs de fraction de fuite étaient semblables avec le CLMA et le PLMA (21,2 % vs 13,3 %, respectivement, P = 0,473). Une vision satisfaisante du larynx a été plus fréquemment obtenue dans le groupe PLMA (21/25 vs 10/25, P = 0,003). L'insufflation gastrique pendant la détermination de la fuite a été plus fréquemment observée dans le groupe CLMA (12/26 vs 2/25 CLMA vs PLMA, respectivement, P = 0,006).

Premedication with midazolam 0.5 mg x kg(-1) po administered 20-30 min preoperatively, is effective in reducing both separation and induction anxiety in children (grade A recommendation), with minimal effect on recovery times. However improved postoperative behavioural outcomes in the postanesthesia care unit, or at home cannot be predicted on a consistent basis.

Purpose The purpose of this evidence-based clinical update is to identify the best evidence when selecting a long-acting local anesthetic agent for single-shot pediatric caudal anesthesia in children.

(P < 0.001), pentobarbitone: 27,8% (P = 0,014), mdthohexitone: 24.9% (P = 0,013), propofol: 21,6% (P = 0,006The belief that sub-hypnotic doses of barbiturate agents enhance pain, perception has been a tenet of anaesthetic practice for >30 yr. In 1960, Dundee ~ used tibial pressure analgesimetry to demonstrate a reduction in nociceptive threshold (NT) in humans following low doses of thiopentone or pentobarbitone. Since then, similar actions of barbiturates have been demonstrated in both human 2 and CAN J ANAESTH 1995 / 42:6 / pp 532-40

From the Department of Anaesthesia, Alberta Children's Hospital at the University of Calgary, Calgary, Alberta.This paper was presented in part at the Canadian Anaesthetists' Society Annual Meeting in Ottawa, June 1989.Address correspondence to: Dr. C. Wood, Department of Anaesthesia, Alberta Children's Hospital, 1820 Richmond Road SW., Calgary, Alberta.Accepted for publication 15th May, 1992. Contamination of the operating theatre with trace concentrations of waste anaesthetic gases is an inevitable consequence of the use of inhalational anaesthetic agents. The health risk to operating theatre personnel resulting from chronic exposure to trace concentrations of these agents has been the subject of numerous studies during the last 20 yr. Among the agents studied, the toxic effects of nitrous oxide have been the focus of much attention. Horace Wells first demonstrated the anaesthetic properties of nitrous oxide in 1844, but it was not until 1956 that the first adverse side effects from its use were reported. In that year, Lassen described bone marrow surpression in patients sedated with nitrous oxide for long-term ventilation) Since then, possible adverse effects on bone marrow, psychomotor function, and reproductive function have been described. 2-8 This has led to concerns regarding possible ill effects from the chronic occupational exposure CAN J ANAESTH 1992 / 39:7 / pp 682-6

One hundred and twenty healthy, elective surgical inpatients were randomly assigned to one of four groups. Between two and three hours before the scheduled time of surgery all patients ingested a marker dye, phenol red, 50 mg in 10 ml water, with placebo tablet alone (Groups 1 and 2), placebo tablet with 150 ml oral fluid (Group 3), or oral ranitidine 150 mg with oral fluid 150 ml (Group 4). Patients in Group 1 received oral diazepam or no premedication, while those in Groups 2, 3, and 4 received IM narcotic and atropine one hour preoperatively. Following induction of anaesthesia the residual gastric fluid was aspirated through a Salem sump tube and its volume, pH, and phenol red content measured. Mean volumes were Group 1: 24 ml; Group 2: 13 ml; Group 3: 17 ml; Group 4: 14 ml. Mean pH values were Group 1: 2.99; Group 2: 3.03; Group 3: 3.44; Group 4: 5.28. The amount of phenol red in the samples indicated at least 90 per cent gastric emptying had occurred in 90 per cent of patients. We conclude that, in healthy patients, 150 ml oral fluid is almost completely emptied from the stomach within two hours of ingestion, even when followed one hour later by narcotic-atropine premedication.

No abstract

Anesthesia and perioperative care of children in an iMR setting were associated with a very low incidence of complications, despite the duration of the procedures involved. Such success depends upon a cohesive team-based approach.