Bi Spectral Index Targeted General Anaesthesia Technique to Reduce Awareness in Patients Undergoing Caesarian Section

Dr Josemine Davis; Dr Amit Rai

Volume : V, Issue : XII, December - 2016

Bi Spectral Index Targeted General Anaesthesia Technique to Reduce Awareness in Patients Undergoing Caesarian Section

Dr Josemine Davis, Dr Amit Rai

Abstract :

The incidence of awareness under anaesthesia for caesarian section is reported to be more than that for other patients undergoing general anaesthesia. The aim of our study was to evaluate whether maintaining a BIS value < 70 during general anaesthesia with inhalational agents in lower segment caesarian section will provide adequate anaesthesia to prevent explicit recall. The study design allowed us to alter the anaesthetic technique to achieve pre-determined BIS values- that is BIS value of 70 till delivery of baby and BIS of 60 thereafter – so as to minimise the probability of recall without adverse effects on mother and neonate. 100 patients in ASAI or II were included in the study. Induction of anaesthesia was carried out using a standard protocol and anaesthetic depth was titrated with isoflurane in 50% N2O to a BIS value of 70 till delivery of baby. After delivery opioids were given, N2O increased to 66% and isoflurane titrated to a target BIS value of 60. Explicit awareness was assessed using a structured post-operative interview. Uterine tone and bleeding was documented and neonatal apgar score noted at 1 minute and 5 minutes.

. No patient had awareness or dreaming during surgery, as seen from the results of post-operative structured interview. The uterus remained responsive to oxytocin even in the presence of volatile agents and there was no incidence of severe uterine bleeding. There were no adverse effects on new born babies as seen from acceptable Apgar scores in all neonates. We concluded that Bispectral index is useful in monitoring the ain state during general anaesthesia for caesarian section and helps to titrate drug delivery and to time intra operative manipulations so as to minimise the risk of intra operative awareness.