Preoperative fasting for paediatric anaesthesia.

Preoperative fasting was introduced to reduce the risk and severity of aspiration pneumonitis. Adequate time (6h) must still be allowed before operation for solid foods to be emptied from the stomach. However, the overwhelming weight of evidence supports the practice of reducing the duration of the preoperative fluid fast for elective paediatric surgical patients [3, 15]. In children allowed free, clear fluids until 2 h before the scheduled time of anaesthesia, gastric contents and thus the risk of aspiration pneumonitis appears to be similar to those children who have endured a longer fast. Potential benefits of reduced thirst, better perioperative experience, improved compliance and reduced hypoglycaemia may be seen. Patients at risk of GOR and aspiration pneumonitis, including those presenting for emergency surgery, must receive special consideration. As aspiration pneumonitis is so rare, careful reporting of complications potentially related to a reduced fasting period is necessary.

Milrinone and the pulmonary vascular system.

In a multicentre study of 99 adult patients undergoing cardiac surgery, if post-operative cardiac failure was demonstrated (pulmonary capillary wedge pressure greater than 8 mmHg, cardiac index less than 2.5 litre min-1 m-2), then a bolus dose of milrinone (50 micrograms kg-1) was given, followed by an infusion at one of three rates (0.375, 0.5 or 0.75 microgram kg-1 min-1), and haemodynamic effects were assessed. Mean pulmonary artery pressures fell by 15% initially (P less than 0.001), and this significant reduction was maintained throughout the infusion period and reversed with the withdrawal of milrinone. Mean pulmonary vascular resistance fell progressively throughout the infusion period, the maximum change (30-40%) being evident at the 12 h point (P less than 0.05). Reversal of this effect after terminating the milrinone infusion was less marked than with pulmonary capillary wedge pressure or mean pulmonary artery pressure. A group of 39 of these patients from two centres were retrospectively divided into three groups: 1. Mitral valve replacement with high baseline pulmonary vascular resistance (greater than 200 dyne s cm-5) 2. Coronary revascularization with lower baseline pulmonary vascular resistance (100-200 dyne s cm-5) 3. Coronary revascularization with high baseline pulmonary vascular resistance (greater than 200 dyne s cm-5). There was a significant reduction in pulmonary vascular resistance and increase in cardiac index in all patients. At the 15 min point, there was significant between-group variation, the fall in pulmonary vascular resistance and increase in cardiac index being greater in Group 1 than in Groups 2 or 3. This difference between groups was not maintained during the infusion.

Minitracheotomy--a life-threatening complication.

A 55-year-old patient developed profuse haemorrhage immediately after insertion of a minitracheotomy tube. Measured blood loss was 1.1 litres, and the bleeding required to be controlled surgically. The cause was a subglottic granuloma which had developed after prolonged tracheal intubation and which was incised during insertion of the minitracheotomy.