Comparison of the incidence of complications at induction and emergence in infants receiving oral atropine vs no premedication.

We studied 120 patients less than 1 yr of age, allocated randomly to receive atropine 40 micrograms kg-1 orally 1 h before operation (group A) or no premedication (group B). All patients underwent a standardized anaesthetic, including inhalation induction with halothane followed by atracurium 0.5 mg kg-1, tracheal intubation and positive pressure ventilation. Monitoring during anaesthesia included heart rate, arterial oxygen saturation, temperature and airway conditions at induction and emergence. The incidence of a decrease in arterial oxygen saturation to 94% or less at induction and recovery was similar in both groups (30.5% at induction, 39% at extubation in group A; 31% at induction, 41% at extubation in group B). There were significantly more airway complications in group B both at induction and emergence (25% and 49%, respectively, compared with 9% and 25% in group A; P < 0.015). Mean heart rate at induction and in the peroperative period was significantly higher in the group receiving atropine (P < or = 0.001). There was an increased incidence of bradycardia (decrease in heart rate of > or = 20%) at induction in the non-premedicated group (23% in group B compared with 10% in group A), but this was not statistically significant. We conclude that the incidence of airway complications at induction and emergence was reduced by orally administered atropine premedication.

Comparison of caudal bupivacaine and diamorphine with caudal bupivacaine alone for repair of hypospadias.

Forty-five boys undergoing repair of hypospadias were allocated randomly to one of two groups. After induction of anaesthesia, 22 patients received 0.25% caudal bupivacaine 0.5 ml kg-1 and diamorphine 30 micrograms kg-1 and the remaining 23 patients received 0.25% caudal bupivacaine 0.5 ml kg-1 alone. Pain scores (Children's Hospital of Eastern Ontario Pain Scale), sedation scores, ventilatory frequency, analgesic requirements and associated side effects were recorded for the first 24 h after operation. The two groups were indistinguishable in age, weight and duration of surgery. There was a statistically significant reduction in early pain scores. There was also a statistically significant increase in the time to first passage of urine in those boys in the diamorphine group who were not catheterized during operation.

The role of continuous positive airway pressure during weaning from mechanical ventilation in cardiac surgical patients.

We investigated the effects of providing patients with continuous positive airway pressure during a short weaning period from mechanical ventilation to extubation. Following elective primary aortocoronary bypass surgery employing cardiopulmonary bypass, 80 patients received intermittent positive pressure ventilation for 5 h. At the end of this time patients were randomly allocated to one of the following three groups for a 2 h period of spontaneous respiration prior to extubation: group CPAP0 = T-piece circuit (n = 27); group CPAP5 = 5 cmH2O of continuous positive airway pressure (n = 27); group CPAP10 = 10 cmH2O of continuous positive airway pressure (n = 26). Following extubation, pulmonary gas exchange was assessed after 1, 2, 4, and 24 h. All patients had good pre-operative lung function. There was a significant increase in the median alveolar-arterial oxygen partial pressure difference and a decrease in the oxygenation index in all three groups during the period of added inspired oxygen which persisted until 24 h post-extubation, but there were no differences between the groups. In patients with good pre-operative lung function requiring primary aortocoronary bypass surgery, the use of continuous positive airway pressure confers no advantage over a simple T-piece attachment during the short period of weaning from mechanical ventilation to extubation.

Randomized placebo-controlled double-blind study of three aprotinin regimens in primary cardiac surgery.

The serine proteinase inhibitor aprotinin significantly reduces postoperative blood loss in patients requiring cardiac surgery using cardiopulmonary bypass. This study compared two low-dose regimens with administration of high-dose aprotinin and a control protocol to determine whether the dose of aprotinin could be greatly decreased but still maintain efficacy after primary cardiac surgery. Some 100 patients were randomly assigned to one of four groups: control group (0.9 per cent saline placebo, n = 25); high-dose group (aprotinin 2 x 10(6) kallikrein inactivator (KI) units intravenous patient bolus and 0.5 x 10(6) KI units h-1 plus 2 x 10(6) KI units into pump prime, n = 25); prime group (aprotinin 2 x 10(6) KI units added to the pump prime, n = 24); and patient group (aprotinin 10(6) KI units intravenous patient bolus plus 10(6) KI units added to the pump prime, n = 26). Only patients from the high-dose and patient groups had reduced intraoperative blood loss, but patients from all three aprotinin-treated groups demonstrated a significant decrease in median postoperative blood loss compared with the control group (high-dose 350 ml, prime 420 ml, patient 340 ml versus control 780 ml; P < 0.001). There was an even greater reduction in measured median postoperative haemoglobin loss within the chest drains in the treated compared with the control patients (high-dose 15 g, prime 24 g, patient 14 g versus control 47 g; P < 0.001). These decreases were statistically the same for all the treated groups; it is possible to lower the dose of aprotinin to approximately one-third of the currently recommended dosage and still obtain significantly reduced postoperative blood loss in primary cardiac surgery.