Table 1

 Incidents involving awareness under general anaesthesia (n = 21)

DetailsIntraoperative presentation
MUA, manipulation under anaesthesia; ECT, electroconvulsive therapy.
Unremarkable anaesthesia with no obvious aetiology (n = 9)
    Cardiac surgery. Aware at sternotomyNil
    Cardiac surgery. Aware at sternotomyTachycardia/hypertension
    Caesarean section. Aware at incisionTachycardia/hypertension
    Burns debridement. Aware during maintenanceNil
    Laparotomy. Aware during maintenanceDiaphoresis
    Minor gynaecology case. Aware when positionedNil
    MUA. Aware during manipulationNil
    ECT. Aware at electrode placementNil
    ECT. Aware at electrode placementNil
Incidents related to volatile agents and vaporisers (n = 8)
    Laparotomy. Aware during maintenance Vaporiser deliberately turned off (hypotension)Nil
    Eye procedure. Awareness at and after intubation. Vaporiser deliberately turned off (hypotension)Nil
    Drainage of pilonidal abscess. Aware during maintenance. Vaporiser turned off; misjudgement of end of procedureNil
    Wound debridement. Aware during maintenance. Vaporiser accidentally turned off during management of pneumothoraxNil
    Gynaecological procedure. Aware during maintenance. Caused by empty vaporiserTachycardia
    Repair of umbilical hernia. Aware during maintenance. Malpositioned vaporiserHypertension, circuit leak
    Axillary block dissection. Aware during maintenance. Malpositioned vaporiserHypertension
    Laminectomy. Awareness during maintenance. Malpositioned vaporiserCircuit leak
Miscellaneous incidents (n = 4)
    Suxamethonium sensitivity in patient intubated for cardioversion
    Aware during difficult intubation
    Aware during difficult intubation
    Aware during intubation for respiratory arrest, due to extravasated intravenous access cannulaPatient movement