General anaesthesia for Nd:YAG laser resection of obstructing endobronchial tumours using the rigid bronchoscope

Provision of general anaesthesia for patients undergoing Nd:YAG laser resection of obstructing endobronchial tumours using the rigid bronchoscope presents unique problems for the anaesthesiologist. We studied 15 patients who underwent 20 of these procedures under general anaesthesia. Patients were anaesthetized and ventilated with either potent inhalation agents via the side arm of the ventilating bronchoscope (Group I: N = 8), or with intravenous agents and the Sanders jet injector attached to the rigid bronchoscope (Group II: N = 12). Patients were paralyzed and ventilation was controlled. The inspired gas mixture was nitrogen and oxygen, and the FIO2 was decreased to 0.3-0.4 during periods of resection. Group I patients had significantly higher peak pCO2's than Group II (8.3 kPa (62 mmHg) vs. 5.6 kPa (44 mmHg); lowest recorded pO2's were comparable and similar to pre-induction values. Both groups exhibited wide blood pressure fluctuations. Heart rates remained within 15 per cent of pre-induction levels. There were no intraoperative deaths, and no airway fires, massive haemorrhages or pneumothoraces. We conclude that these procedures can be undertaken with the use of general anaesthesia and the rigid bronchoscope, but that patients may encounter potentially serious respiratory or haemodynamic instability during the procedure.