Abstract :
Incidence of awareness in patients undergoing cardiac surgery is up to 23% compared to its incidence of
1% during general surgery. In our institute we conducted study in 40 patients undergoing valve surgeries
and compared volatile agent vs. conventional method with help of BIS monitoring. Partly because of
the difficulty of administering volatile agents during cardiopulmonary bypass (CPB), total intravenous
anaesthesia (TIVA) has been a popular technique used by cardiac anaesthetists in the last few decades.
However, the possibility that volatile agents cut back mortality and the incidence of myocardial infarction
by preconditioning the myocardium has stimulated a revival of interest in their use for cardiac anaesthesia.
We observed the higher BIS values were seen in conventional group with requirement of higher dose of
propofol as a rescue to avoid intraoperative awareness. The haemodynamics were steadily maintained in
isoflurane group. The inotrope score was less in isoflurane group indicating myocardial protective effect of
isoflurane.
In conclusion, in patients undergoing heart surgery with CPB, the findings of this study indicate that
appropriate use of isoflurane to maintained depth of anaesthesia during CPB should be monitored with
use of BIS and ETAC.
Keyword :
Total intravenous anaesthesia (TIVA), Cardiopulmonary bypass (CPB), Isoflurane. Bispectral index, Depth of anaesthesia.