5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: protocol, methods, and analysis of data.

BACKGROUND: Accidental awareness during general anaesthesia (AAGA) with recall is a potentially distressing complication of general anaesthesia that can lead to psychological harm. The 5th National Audit Project (NAP5) was designed to investigate the reported incidence, predisposing factors, causality, and impact of accidental awareness. METHODS: A nationwide network of local co-ordinators across all the UK and Irish public hospitals reported all new patient reports of accidental awareness to a central database, using a system of monthly anonymized reporting over a calendar year. The database collected the details of the reported event, anaesthetic and surgical technique, and any sequelae. These reports were categorized into main types by a multidisciplinary panel, using a formalized process of analysis. RESULTS: The main categories of accidental awareness were: certain or probable; possible; during sedation; on or from the intensive care unit; could not be determined; unlikely; drug errors; and statement only. The degree of evidence to support the categorization was also defined for each report. Patient experience and sequelae were categorized using current tools or modifications of such. CONCLUSIONS: The NAP5 methodology may be used to assess new reports of AAGA in a standardized manner, especially for the development of an ongoing database of case reporting. This paper is a shortened version describing the protocols, methods, and data analysis from NAP5--the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home.

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 (NAP5) of the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland into accidental awareness during general anaesthesia (AAGA) 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% confidence interval (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 AAGA 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 AAGA (75%) were judged preventable. In 12%, AAGA care was judged good and the episode not preventable. The contributory and human factors in the genesis of the majority of cases of AAGA included medication, patient, and education/training. The findings have implications for national guidance, institutional organization, 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. NAP5 methodology provides a standardized template that might usefully inform the investigation of claims or serious incidents related to AAGA.

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 (NAP5) on accidental awareness during general anaesthesia (AAGA). 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% confidence interval 1:16,700-23,450). However, there was considerable variation across subtypes of techniques or subspecialities. The incidence with neuromuscular block (NMB) was ~1:8200 (1:7030-9700), and without, it was ~1:135,900 (1:78,600-299,000). The cases of AAGA reported to NAP5 were overwhelmingly cases of unintended awareness during NMB. 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, NMB, 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, mostly 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 NMB. 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 NAP5--the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home.

The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: protocol, methods and analysis of data.

Accidental awareness during general anaesthesia with recall is a potentially distressing complication of general anaesthesia that can lead to psychological harm. The 5th National Audit Project was designed to investigate the reported incidence, predisposing factors, causality and impact of accidental awareness. A nationwide network of local co-ordinators across all UK and Irish public hospitals reported all new patient reports of accidental awareness to a central database, using a system of monthly anonymised reporting over a calendar year. The database collected the details of the reported event, anaesthetic and surgical technique, and any sequelae. These reports were categorised into main types by a multidisciplinary panel, using a formalised process of analysis. The main categories of accidental awareness were: certain or probable; possible; during sedation; on or from the intensive care unit; could not be determined; unlikely; drug errors; and statement only. The degree of evidence to support the categorisation was also defined for each report. Patient experience and sequelae were categorised using current tools or modifications of such. The 5th National Audit Project methodology may be used to assess new reports of accidental awareness during general anaesthesia in a standardised manner, especially for the development of an ongoing database of case reporting. This paper is a shortened version describing the protocols, methods and data analysis 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: 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.

Immunity to cytomegalovirus in women with unexplained recurrent spontaneous abortion.

Humoral and cellular immunity to cytomegalovirus (CMV) has been assessed in women suffering unexplained recurrent spontaneous abortions (RSA). A significantly lower prevalence of serum anti-CMV antibodies was observed for RSA women compared with either their male partners or age-matched female controls, unlike for serum antibodies to Herpes simplex virus. In addition, there was a markedly impaired lymphocyte proliferative response to CMV for CMV-sero-positive RSA women compared with CMV-seropositive controls. These results indicate that women with unexplained RSA have difficulty in responding to CMV, and are of significance when considering leukocyte transfusion immunotherapy.

Meeting the needs of families and carers on acute psychiatric wards: a nurse-led service.

The needs of families and carers are often not met by the busy staff on inpatient units. A nurse-led family and carers service was set up on three adult acute psychiatric wards. A four-session protocol was developed for structuring sessions with families and carers. Methods of engaging reluctant carers were developed. Satisfaction rates are high. Families and carers value the emotional support, improved communication, help and advice. About one quarter are referred on for further input after discharge. A nurse-run service for the families and carers can make a significant difference to those who use it, providing support, creating a working alliance and improving the two-way exchange of information.

Performance of the Baxter disposable patient-controlled analgesia infusor under hyperbaric conditions.

Hyperbaric oxygen treatment may require the concurrent administration of drugs. A study was performed to assess the suitability of the infusor device from the Baxter Patient-Controlled Analgesia system, for drug delivery during hyperbaric therapy. Thirty infusor devices were used to deliver 5% dextrose, 50% dextrose or propofol solutions under conditions 1 and 2.3 atmospheres of pressure. The increased pressure caused an increase in flow of 4.27%, 1.79% and 9.84% for 5% dextrose, propofol and 50% dextrose respectively.

The recognition of critical incidents: quantification of monitor effectiveness.

We have conducted a prospective analysis of all reported critical incidents which occurred during the period from admission to the anaesthetic room until discharge from the operating theatre complex over a 1-year. The aim was to identify which monitors were most effective for initial recognition of those incidents. All patients were monitored in accordance with the recommendations of the procedures gave rise to 338 recorded critical incidents, of which 27 were deemed to have caused, or been likely to cause, patient harm. We have shown that a combination of arterial blood pressure measurement (noninvasive), ECG, pulse oximetry and clinical observation detected 90% of all reported critical incidents, and all the incidents causing patient harm. We have also shown that blood pressure monitoring by itself, and combination with ECG and pulse oximetry, detected proportionately more critical incidents resulting in patient harm (incidents resulting in harm remaining incidents, for each monitor) than clinical observation alone (p < 0.05) and all other remaining forms of monitoring together (p < 0.01).

Neurofibromatosis: clinical presentations and anaesthetic implications.

The neurofibromatoses are autosomal dominant diseases that have widespread effects on ectodermal and mesodermal tissue. The commonest member of the group is neurofibromatosis type 1 (NF1) which varies in severity but which can affect all physiological systems. Neurofibromas are the characteristic lesions of the condition and not only occur in the neuraxis but may also be found in the oropharnyx and larynx; these may produce difficulties with laryngoscopy and tracheal intubation. Pulmonary pathology includes pulmonary fibrosis and cystic lung disease. The cardiovascular manifestations of NF1 include hypertension, which may be associated with phaeochromocytoma or renal artery stenosis. Neurofibromas may also affect the gastrointestinal tract and carcinoid tumours may be found in the duodenum. This review documents the aetiology and clinical manifestations of the neurofibromatoses and discusses their relevance to the anaesthetist.

The use of insulin pump therapy in adolescents.

Continuous subcutaneous insulin infusion (CSII) systems have been used in diabetes management since the mid-1970s. Investigators have reported encouraging results with CSII use in adult subjects with dramatically improved glucose control, reversal of some complications, and high acceptance and compliance rates. We have studied 10 adolescents and 3 young adults using CSII for diabetes management. Only the three young adults (ages 20, 24, 34 years) have had markedly improved metabolic control, sustained pump use, and made adequate psychological adjustment to CSII therapy. Adolescent subjects, (ages 9-17 years), experienced problems with peer acceptance of pumps, had difficulty with infusion needle insertion and skin care, were unable to perform home blood glucose monitoring consistently, made nonadvised manipulations of insulin dosage and reported mechanical problems with CSII devices more frequently than the young adult subjects. Mean duration of CSII use in adolescent subjects (6.1 months) was significantly less than mean use (30.6 months) among the young adults (p less than 0.01). Currently, adults appear to have greater success than adolescents in using CSII for diabetes management.

A comparison of the intubating and standard laryngeal mask airways for airway management by inexperienced personnel.

Twenty-four inexperienced participants were timed inserting the intubating laryngeal mask airway and the laryngeal mask airway in 75 anaesthetised subjects. Adequacy of ventilation was assessed on a three-point scale. The pressure at which a leak first developed around the device's cuff was also measured. There was no significant difference in insertion time or the likelihood of achieving adequate ventilation between devices. However, the intubating laryngeal mask airway was better at providing adequate ventilation without audible leak (58/75 (77%) vs. 42/75 (56%); p = 0.009). The median (range [IQR]) pressure at which an audible leak developed was higher for the intubating laryngeal mask airway, 34.5 (14-40 [29-40]) cmH2O, than for the laryngeal mask airway, 27.5 (14-40 [22-33]) cmH2O (p < 0.001). The intubating laryngeal mask airway is worthy of further consideration as a tool for emergency airway management for inexperienced personnel.

Fibreoptic views through the laryngeal mask and the intubating laryngeal mask.

BACKGROUND AND OBJECTIVE: The intubating laryngeal mask (intubating laryngeal mask airway) was designed to facilitate blind intubation. Its value as an adjunct to fibreoptic laryngoscopy has not been evaluated. This study compares the intubating laryngeal mask airway with the standard laryngeal mask airway as conduits for fibreoptic laryngoscopy. METHODS: The fibreoptic view of the laryngeal inlet was graded via both devices in 60 anaesthetized patients. The fibreoptic view through the intubating laryngeal mask airway was assessed after the central epiglottic elevator bar had been lifted out of the field of vision by an 8-mm Euromedical tracheal tube, which was inserted to a depth of 18 cm. The fibreoptic view from the aperture bars of the laryngeal mask was recorded. RESULTS: The vocal cords were viewed less frequently through the intubating laryngeal mask airway (52%) than through the laryngeal mask airway (92%) [difference = 40% (95% CI = 26% to 54%), P < 0.0001]. CONCLUSION: The view of the laryngeal inlet is better through the laryngeal mask airway than through a tracheal tube inserted to 18 cm in the intubating laryngeal mask.