Barker, Jill Patricia; (1996) The metabolic and hormonal response to cataract surgery: A comparison between general and local anaesthesia. Doctoral thesis (M.D), UCL (University College London).

Text out.pdf Download (6MB)

Abstract

This thesis compares the endocrine and metabolic response to cataract extraction in patients receiving either general or local anaesthesia. Under general anaesthesia, plasma cortisol concentrations increase more than two-fold during cataract surgery, with smaller changes in circulating glucose and catecholamine concentrations. Both retrobulbar and peribulbar anaesthesia completely abolish these changes. Retrobulbar blockade also improves cardiovascular stability, as measured by changes in heart rate and mean arterial pressure. When retrobulbar blockade is combined with general anaesthesia, changes in circulating cortisol and glucose concentrations are prevented during surgery, but there is a marked increase in cortisol concentration during the immediate postoperative period. Similar increases in cortisol concentration are seen in non-insulin-dependent diabetic (NIDDM) patients receiving general anaesthesia. The glycaemic response is greater in NIDDM than in non-diabetic patients, and there is a failure of insulin secretion postoperatively in the diabetic patients receiving general anaesthesia. Retrobulbar blockade maintains hormonal and metabolic stability, which is important in these patients, in whom cataracts are a common complication. The results of a postoperative questionnaire on 231 patients following cataract surgery under either general or local anaesthesia show the acceptability of both techniques. There is significantly less nausea and sore throat in the local anaesthetic patients, but more bruising of the eye. There is no difference in the severity of postoperative pain, but local anaesthetic patients drank and ate much earlier following their operations. The results provide evidence of the benefits of local anaesthesia for cataract surgery in the elderly patient. Both peribulbar and retrobulbar blockade prevent the metabolic and hormonal changes seen when surgery is performed under general anaesthesia and provide better cardiovascular stability. The findings are particularly important to the diabetic patient.

Download activity - last month

Export as XMLJSONCSV

Download activity - last 12 months

Export as CSVJSONXML

Downloads by country - last 12 months

Export as CSVXMLJSON

Archive Staff Only

View Item