Incidence of awareness during general anaesthesia in procedures using the apnoeic oxygenation technique : A prospective observational study.

Accidental Awareness under General Anaesthesia (AAGA) is a serious but preventable complication that can lead to long term potential psychological consequences such as anxiety, depression, PTSD. Intraoperative awareness is characterized by intraoperative consciousness and postoperative recall of events. Patients may experience auditory recalls, recall of disastrous experience of hurtful surgical stimulation. In scenarios where neuromuscular blockade is used patients may experience a feeling of suffocation , paralysis which is new and deeply distressing for the patient . Patients undergoing procedures requiring apnoeic oxygenation techniques may be prone to AAGA . This is due to the use of neuromuscular blockade which blinds the practitioner to the most reliable indicator of insufficient anaesthesia as the patient cannot move in response to painful stimulus Also, in such procedures there is a rapid pace from induction to procedural stimulation. There are various methods to assess AAGA such as monitors like BP, heart rate, bispectral index, end tidal anaesthetic concentration , but none have been found to be totally efficacious in detecting awareness under anaesthesia. Incidence of AAGA was found out to be more when patients were specifically queried about it , in contrast to surveys which relied on retrospective reviews of patient initiated reports.

In this study we aim to find the incidence of awareness under anaesthesia when apnoeic oxygenation techniques were employed for procedures and to analyze the factors associated with the same.