RECENT ADVANCES IN ANAESTHETICS

Abstract

There are three main types of anaesthesia in use to-day : (1) inhalation combined with premedication, (2) spinal combined with premedication, and (3) intravenous, with or without premedication. I will deal with them in this order. Before considering the anaesthetics themselves it is advisable to stress an important point?namely, that all patients who are to undergo a major surgical operation ought to be carefully investigated. This should include a blood and urine analysis, in addition to a general clinical examination. Special attention is paid to the blood pressure and the Moot-McKesson cardiac energy index. The formula for this index provides an approxi mate index to the cardiac reserve. ,_ . . _ pulse pressurexlOO _.. . , . A . Moot s index = __.??-.-=50 (in normal subjects) diastolic pressure Patients presenting an index of between 40 and 60 show ample cardiac reserve ; those in whom the index lies between 25 and 40, or between 60 and 75, have probably adequate cardiac reserve, whilst the reserve is gravely inadequate in those having an index below 25 or above 75. (Tliis index is unreliable in cases of ihyro toxicosis, owing to the high pulse pressure.) No enemata, purges, or any other form of dehydration should be per mitted for at least forty-eight hours before any major operation. , The patient is supplied with ample fluids and glucose, and everything is done to ensure that his general condition is the best the pathological state allows.