The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: patient experiences, human factors, sedation, consent and medicolegal issues

Abstract

The 5th National Audit Project of the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland into accidental awareness during general anaesthesia yielded data related to psychological aspects from the patient, and the anaesthetist, perspectives; patients' experiences ranged from isolated auditory or tactile sensations to complete awareness. A striking finding was that 75% of experiences were for < 5 min, yet 51% of patients (95% CI 43-60%) experienced distress and 41% (95% CI 33-50%) suffered longer-term adverse effect. Distress and longer-term harm occurred across the full range of experiences but were particularly likely when the patient experienced paralysis (with or without pain). The patient's interpretation of what is happening at the time of the awareness seemed central to later impact; explanation and reassurance during suspected 1102

Recommendations for standards of monitoring during anaesthesia and recovery 2015 : Association of Anaesthetists of Great Britain and Ireland

“…If so, a detailed handover must be delivered to the incoming anaesthetist and this should be recorded in the anaesthetic record. A handover checklist is useful, and one example of this is the ‘ABCDE’ aide memoir suggested in the NAP5 report 13, 14, 15. When taking over care of a patient (including when returning after relief for a break), the incoming anaesthetist should conduct a check to ensure that all appropriate monitoring is in place with suitable alarm limits (see below).…”

“…However, there is no compelling evidence that routine use of depth of anaesthesia monitoring for volatile agent‐based general anaesthetics reduces the incidence of accidental awareness when end‐tidal agent monitoring is vigilantly monitored and appropriate low agent alarms are set 13, 22.…”

“…Before transfer, appropriate monitoring must be commenced. Use of a pre‐transfer checklist is recommended 13. Oxygen saturation, ECG and NIBP should be monitored in all patients.…”

“…Data on the efficacy of these devices in correctly predicting accidental awareness during general anaesthesia (AAGA) or correctly predicting an adequate level of anaesthesia, remains inconsistent and debated 31. However, data from these monitors may provide an additional source of information on the patient's condition.The NAP5 project published in 2014 made a number of recommendations on risk factors for AAGA and the place of depth of anaesthesia monitoring 13, which can be summarised as: the incidence of reports of AAGA was 1 in 8000 when neuromuscular blocking drugs were used (as high as 1:670 in caesarean section) and 1 in 136 000 when they were not (i.e., implying a focus should specifically be on paralysed patients);about half of the reports of AAGA occurred around the time of induction of anaesthesia and transfer from anaesthetic room to the operating theatre.almost 20% of AAGA reports occurred at the time of emergence from general anaesthesia and were commonly if not universally related to inadequate reversal of neuromuscular blockade Building on these recommendations, the AAGBI Working Party makes the following recommendations: Depth of anaesthesia monitoring is recommended when neuromuscular blockade is used in combination with TIVA;Depth of anaesthesia monitoring should logically commence from induction of anaesthesia and be continued at least until the completion of surgical and anaesthetic interventions (i.e., up to the point where it is intended to awaken the patient);Depth of anaesthesia monitoring is recommended during transfer of patients receiving TIVA and neuromuscular blockade, but presents difficulties, because portable battery powered depth of anaesthesia monitors are not widely available. Such devices may come to the market in the future and their efficacy will need to be separately evaluated;…”

“…The NAP5 project published in 2014 made a number of recommendations on risk factors for AAGA and the place of depth of anaesthesia monitoring 13, which can be summarised as: the incidence of reports of AAGA was 1 in 8000 when neuromuscular blocking drugs were used (as high as 1:670 in caesarean section) and 1 in 136 000 when they were not (i.e., implying a focus should specifically be on paralysed patients);about half of the reports of AAGA occurred around the time of induction of anaesthesia and transfer from anaesthetic room to the operating theatre.almost 20% of AAGA reports occurred at the time of emergence from general anaesthesia and were commonly if not universally related to inadequate reversal of neuromuscular blockade …”