Canadian Journal of Anesthesia, Vol 27, 491-495, Copyright © 1980 by Canadian Anesthesiologists' Society

Aetiology and Control of Cardiovascular Reactions During Trans-Sphenoidal Resection of Pituitary Microadenomas

¹ Department of Anaesthesia, Montreal Neurological Hospital and Institute, 3801 University Street, Montreal, Quebec, Canada, H3A 2B4

Two groups of 12 patients were studied to determine the causes of hypertension during trans-sphenoidal resection of pituitary microadenomas. Two concentrations of lidocaine, 0.5 and 1.0 percent with epinephrine 1/200,000, were used to infiltrate the nose and uppergingiva. Heart rate, electrocardiogram lead II and systolic and diastolic arterial blood pressures were monitored. Three stages were observed for changes in above parameters: nasal infiltration, nasal dissection and Sellar exploration. Highly significant reductions in arterial blood pressure and pulse rate responses to infiltration and nasal dissection were achieved by increasing the lidocaine concentration used for infiltration from 0.5 to 1.0 per cent (p < 0.05). Our findings implicate reflex from nasal stimulation as the main cause of the adverse cardiovascular effects. Only minimal changes accompanied the progress of the intrasellar dissection in both groups.