Clinical predictors of anaesthetic complications in children with respiratory tract infections.

Details of the preoperative condition, in particular symptoms of respiratory tract infections (RTI), perioperative management and the occurrence of perioperative complications, were collected in a survey of 2051 children. Logistic regression was used to determine which variables were predictors of anaesthetic adverse events. 22.3% of the children had symptoms of an RTI on the day of surgery, and 45.8% had a 'cold' in the preceding 6 weeks. Logistic regression returned eight variables. They were method of airway management, parent states the child has a 'cold' on the day of surgery, child has nasal congestion, child snores, child is a passive smoker, induction agent chosen, child produces sputum, and whether reversal agent used. Orotracheal intubation was associated with an increased probability of complications when compared with laryngeal mask airway and facemask. RTI in the preceding 6 weeks did not increase probability of complications. Wheeze, fever, malaise and age could not be excluded as predictors in this study because children with these symptoms and infants with colds were effectively excluded from the study.

A timed reexpansion inspiratory manoeuvre (TRIM) for treating oxyhaemoglobin desaturation in children following a period of apnoea--studies in an animal model.

Our clinical experience has shown that the use of a constant distending airway pressure of 30 cm water for 10 s, termed a timed reexpansion inspiratory manoeuvre (TRIM), is often successful in correcting oxyhaemoglobin desaturation in anaesthetized children. The aim of this study was to assess the efficacy of TRIM in lambs. Following a standard relaxant anaesthetic, ventilation was stopped and oxyhaemoglobin saturation allowed to fall to 70% and the time taken to return to baseline was compared between three groups. The median time was 42.5 s when ventilation was restarted with 33% oxygen in nitrous oxide (33% group), 30 s when ventilation was restarted with 100% oxygen (100% group) and 22.5 s with a TRIM before restarting ventilation with 33% oxygen in nitrous oxide (TRIM group). The correction of desaturation was more rapid in the TRIM group compared with the 33% group (P < 0.004) and the 100% group (P < 0.003). Oxyhaemoglobin desaturation due to apnoea in anaesthetized lambs is more effectively treated with a TRIM than by increasing the inspired oxygen fraction.

Anatomical landmarks of the inguinal canal in prepubescent children.

BACKGROUND: Most adult anatomical texts state that the deep inguinal ring is situated midway between the anterior superior iliac spine and the pubic tubercle. The aim of this study was to determine if this was true in prepubescent children. METHODS: A total of 107 inguinal ligaments and canals were measured during inguinal operations in 80 children (68 boys, age range 1-118 months). RESULTS: The length of the inguinal ligament increased from a median of 4.3 cm (range 3.6-6.8) at less than 1 year of age to 7.5 cm (range 6.7-10.1) at over 4 years of age. The internal ring was situated medial to the midpoint of the inguinal ligament throughout childhood. The ratio of internal ring to public tubercle over inguinal ligament length was 42% (range 27-58) at less than 2 years; and 34% (range 25-46) at over 4 years. The inguinal canal remained short (median 1 cm (range 0.7-1.1) at less than 2 years, and median 1.1 cm (range 0.7-2.3) at over 4 years) suggesting that growth of the inguinal region in this age group occurs outside the canal. CONCLUSIONS: These results have implications for the siting of incisions, and question the necessity of opening the inguinal canal in children.

A national survey of atropine use by Australian anaesthetists.

All Fellows of the Faculty of Anaesthetists, Royal Australasian College of Surgeons (now Australian and New Zealand College of Anaesthetists) were surveyed by mail regarding their use of prophylactic atropine. They were asked whether their usual practice was to give atropine for the following indications: premedication, induction of anaesthesia, intubation of the trachea, one dose of suxamethonium, a second dose of suxamethonium, halothane anaesthesia, oropharyngeal surgery, bronchoscopy and eye surgery. For each indication they were asked for details regarding their practice concerning neonates, infants, children and adults. The large response rate of 86% of Fellows returning a survey form ensured that the survey was representative of Australian anaesthetic practice. Results indicate a wide variation in practice regarding the prophylactic use of atropine, with neonates, infants and children more likely to receive prophylactic atropine than adults. The majority do not give prophylactic atropine as premedication, but may give it in the younger age groups at induction, and many (67%) only give it if they are to administer suxamethonium to a child. The only indication for which a convincing majority (> 80%) of anaesthetists agreed that prophylactic atropine should be given was when a repeated dose of suxamethonium was to be given to neonates, infants or children. A large proportion of anaesthetists (> 80%) agreed that atropine is not necessary prior to halothane anaesthesia in all age groups, nor as premedication, at induction, at intubation, prior to oropharyngeal surgery or prior to eye surgery in adults. These results were compared with the practice at a major paediatric hospital where the practice is not to use routine prophylactic atropine.

Oral midazolam is an effective premedication for children having day-stay anaesthesia.

The effect of oral premedication was studied in a double-blind, randomised trial of 200 children undergoing day-stay anaesthesia. Midazolam 0.25 mg/kg, midazolam 0.5 mg/kg, diazepam 0.5 mg/kg or a placebo was given orally one hour prior to anaesthesia. Patient state was assessed at nine stages, from administration of the premedication up to and including induction of anaesthesia, using a four-point behavioural scale. Patient state was also assessed postoperatively in the recovery area and the day-stay ward. There was no difference between the four groups until induction of anaesthesia. At this stage 82% of children were either asleep or awake and calm. Patients who received midazolam 0.5 mg/kg were more likely to be asleep or awake and calm at induction rather than other groups (P = 0.05). Children receiving midazolam 0.5 mg/kg or diazepam 0.5 mg/kg slept longest in the post anaesthetic recovery room (P less than 0.005), and spent most time there (P less than .005). There was no difference between groups in the length of time spent in the day-stay ward or in the number of overnight admissions. The study shows that a high proportion of unsedated children are calm at induction of anaesthesia and that oral midazolam is an effective premedication in children for day-stay anaesthesia.