Cardiovascular effects of oesophageal dilation under general anaesthesia.

Myocardial ischaemia and cardiac arrhythmias may occur during oesophageal dilation under conscious sedation, but no prospective data exist regarding dilation under general anaesthesia. We have studied the haemodynamic and electrocardiographic changes during routine oesophageal balloon dilation under general anaesthesia. Ten consecutive patients with benign oesophageal strictures were evaluated. Arterial oxygen saturation was measured by continuous pulse oximetry, ECG was recorded continuously with a Holter tape recorder, and blood pressure was measured non-invasively every five minutes during the procedure. Four patients developed significant hypotension at the time of balloon inflation with two patients requiring medical intervention to re-establish sufficient cardiovascular function. Tachycardia and ST-deviation occurred in four and three patients, respectively, during the general anaesthesia, but was not associated with the actual time of oesophageal distension. Thus, all cases of myocardial ischaemia were related to the time of extubation. No lasting complications were seen, and all patients could be discharged a maximum of 24 hours after the procedure. Pneumatic dilation of the oesophagus under general anaesthesia may be associated with significant hypotension, but the pathogenetic mechanisms involved are not clear. In this pilot study, the observed hypotension was not related to concurrent myocardial ischaemia.