[Awareness in paediatric anaesthesia: Review of the literature]. / Le réveil peropératoire en anesthésie pédiatrique: Revue de la littérature.

Awareness, or unwanted recall of intraoperative events during general anesthesia, is not a frequent complication. For adul ts, this complication can lead to adverse psychological consequences like post-traumatic stress disorder (PTSD). The incidence of awareness seems to be higher in children than in adults, although in this population, the causes and consequences of awareness remain difficult to define. Compared to adults, there are less psychological effects and complications after awareness and no PTSD has been declared in children. The revival of interest concerning awareness has been stimulated by the availability of new technologies to assess the depth of anesthesia. These monitoring seem to be more accurate in children older than 1 year. More studies are needed to evaluate these monitoring, their ability to detect awareness and, finally, to explore long term consequences of awareness in children.

Le réveil peropératoire (RPO) ou le souvenir non désiré d'évènements au cours d'une anesthésie générale (AG) est une complicat ion peu fréquente. Chez l'adulte, cette situation peut conduire à des complications psychologiques délétères comme le syndrome de stress posttraumatique (SSPT). L'incidence du RPO apparaît plus élevée chez l'enfant que chez l'adulte quoique dans cette population, les causes et les conséquences du RPO restent difficiles à définir. Comparativement à l'adulte, il n'y a pas d'effets psychologiques délétères après le RPO chez l'enfant et aucun SSPT n'a été déclaré. Le regain d'intérêt concernant le RPO a été stimulé par l'apparition de nouvelles technologies permettant de mesurer la profondeur de l'anesthésie. Ces moniteurs semblent assez précis chez les enfants de plus d'un an. De nouvelles études sont nécessaires pour évaluer l 'uti lité de ces moniteurs à détecter et à prévenir le RPO. Les conséquences du RPO à long terme chez l'enfant devraient également être explorées.

The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: summary of main findings and risk factors.

We present the main findings of the 5th National Audit Project on accidental awareness during general anaesthesia. Incidences were estimated using reports of accidental awareness as the numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ~1:19 600 anaesthetics (95% CI 1:16 700-23 450). However, there was considerable variation across subtypes of techniques or subspecialties. The incidence with neuromuscular blockade was ~1:8200 (1:7030-9700), and without it was ~1:135 900 (1:78 600-299 000). The cases of accidental awareness during general anaesthesia reported to 5th National Audit Project were overwhelmingly cases of unintended awareness during neuromuscular blockade. The incidence of accidental awareness during caesarean section was ~1:670 (1:380-1300). Two thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental; rapid sequence induction; obesity; difficult airway management; neuromuscular blockade; and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, most due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex; age (younger adults, but not children); obesity; anaesthetist seniority (junior trainees); previous awareness; out-of-hours operating; emergencies; type of surgery (obstetric, cardiac, thoracic); and use of neuromuscular blockade. The following factors were not risk factors for accidental awareness: ASA physical status; race; and use or omission of nitrous oxide. We recommend that an anaesthetic checklist, to be an integral part of the World Health Organization Safer Surgery checklist, is introduced as an aid to preventing accidental awareness. This paper is a shortened version describing the main findings from 5th National Audit Project - the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home#pt.

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

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 accidental awareness during general anaesthesia or at the time of report seemed beneficial. Quality of care before the event was judged good in 26%, poor in 39% and mixed in 31%. Three quarters of cases of accidental awareness during general anaesthesia (75%) were judged preventable. In 12% of cases of accidental awareness during general anaesthesia, care was judged good and the episode not preventable. The contributory and human factors in the genesis of the majority of cases of accidental awareness during general anaesthesia included medication, patient and education/training. The findings have implications for national guidance, institutional organisation and individual practice. The incidence of 'accidental awareness' during sedation (~1:15 000) was similar to that during general anaesthesia (~1:19 000). The project raises significant issues about information giving and consent for both sedation and anaesthesia. We propose a novel approach to describing sedation from the patient's perspective which could be used in communication and consent. Eight (6%) of the patients had resorted to legal action (12, 11%, to formal complaint) at the time of reporting. The 5th National Audit Project methodology provides a standardised template that might usefully inform the investigation of claims or serious incidents related to accidental awareness during general anaesthesia.

Awareness in children: a secondary analysis of five cohort studies.

Five recent cohort studies have shown a frequency of awareness in paediatric anaesthesia of between 0.2% and 1.2%, but they were not individually large enough to identify risk factors. This study pooled raw data from these five studies to identify factors associated with awareness in children. The outcome of awareness was taken as the cases judged to be most likely awareness cases in each study. Logistic regression was used to identify awareness-associated factors. A combined sample of 4486 anaesthetics revealed 33 cases of awareness. Unadjusted analysis demonstrated weak evidence that nitrous oxide used as an anaesthetic maintenance adjunct was associated with awareness (OR 2.04 (95% CI 0.97-4.33), p=0.06), and some evidence that use of a tracheal tube was associated with awareness (OR 2.78 (95% CI 1.11-6.94), p=0.03). Multivariable regression analysis revealed that nitrous oxide maintenance and use of a tracheal tube were independently associated with awareness (nitrous oxide, OR 2.4 (95% CI 1.08-5.32), p=0.03; tracheal tube, OR 3.0 (95% CI 1.20-7.56), p=0.02).

Awareness during general anaesthesia--implications of explicit intraoperative recall.

Anaesthesia awareness (AA) is postoperative recall of events experienced under general anaesthesia. Most frequently patients remember an auditory perception, the feeling of motor function lost, pain, helplessness, anxiety, panic, impending death. The prevalence of awareness in nonobstetric and noncardiac surgical cases is 0.1%-0.2%. The prevalence is higher in cardiac surgery, obstetric and major trauma cases. According to the results of many studies light anaesthesia is the most common cause of the AA. Posttraumatic stress disorder appears in 33%-56% of patients who experienced awareness during general anaesthesia. Extreme awareness experiences are very uncommon, but traumatic and can have lasting effects on patients. Several brain-function monitors based on the processed electroencephalogram or evoked potentials have been developed to assess anaesthetic depth. Measures to prevent awareness include avoidance of light anesthesia, gaining more knowledge about patient anaesthetic requirements and development of methods to detect consciousness during anesthesia.

The incidence of intraoperative awareness in cardiac surgery fast-track treatment.

OBJECTIVE: To determine the occurrence of intraoperative awareness with recall in cardiac surgery patients undergoing fast-track anesthetic management in a direct-admission postanesthetic care unit. DESIGN: Prospective. SETTING: University-affiliated heart center. PARTICIPANTS: Five hundred thirty-four patients undergoing fast-track anesthesia. INTERVENTIONS: Using a structured interview process as part of the quality-assurance program. METHODS AND MAIN RESULTS: All fast-track patients during an 8-month period were entered into the study at a university hospital. Each patient was interviewed by research staff with the same standard set of questions within the first 24 hours of surgery. Follow-up interviews were performed on day 3 or 4 as well as on day 6 or 7 postsurgery. Awareness was defined by the presence of explicit memory of any event from the induction of anesthesia to the recovery of consciousness in the postanesthetic care unit (PACU). A final study population of 514 patients was evaluated. None of the answers given by any patient during any of the 3 interviews indicated intraoperative awareness, with the exception of one 54-year-old male patient. Most likely, this potential awareness did not take place during the operation but was caused by inadequate awakening in the PACU. CONCLUSION: Therefore, the authors conclude that, with respect to intraoperative awareness, the "Leipzig Fast-Track Concept" with the use of ultra-short-acting opioids should be considered as a safe method of management of patients undergoing a wide variety of cardiac operations.