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These guidelines provide a strategy to manage unanticipated difficulty with tracheal intubation. They are founded on published evidence. Where evidence is lacking, they have been directed by feedback from members of the Difficult Airway Society and based on expert opinion. These guidelines have been informed by advances in the understanding of crisis management; they emphasize the recognition and declaration of difficulty during airway management. A simplified, single algorithm now covers unanticipated difficulties in both routine intubation and rapid sequence induction. Planning for failed intubation should form part of the pre-induction briefing, particularly for urgent surgery. Emphasis is placed on assessment, preparation, positioning, preoxygenation, maintenance of oxygenation, and minimizing trauma from airway interventions. It is recommended that the number of airway interventions are limited, and blind techniques using a bougie or through supraglottic airway devices have been superseded by video- or fibre-optically guided intubation. If tracheal intubation fails, supraglottic airway devices are recommended to provide a route for oxygenation while reviewing how to proceed. Second-generation devices have advantages and are recommended. When both tracheal intubation and supraglottic airway device insertion have failed, waking the patient is the default option. If at this stage, face-mask oxygenation is impossible in the presence of muscle relaxation, cricothyroidotomy should follow immediately. Scalpel cricothyroidotomy is recommended as the preferred rescue technique and should be practised by all anaesthetists. The plans outlined are designed to be simple and easy to follow. They should be regularly rehearsed and made familiar to the whole theatre team., (© The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia.)

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 Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

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., (© The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

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., (© The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

We have measured the steady state urinary clearances of atracurium, given by constant infusion, and laudanosine in eight patients undergoing artificial ventilation; all had normal renal function (mean creatinine clearance 81 ml min-1). Mean (SD) urinary clearance of atracurium was 0.55 (0.5) ml kg-1 min-1; that of laudanosine was 0.33 (0.2) ml kg-1 min-1. Simultaneous plasma clearances were 7.1 (1.4) ml kg-1 min-1 and 3.8 (1.5) ml kg-1 min-1, respectively. Notional haemofiltration clearances of the two substances were measured also in seven critically ill patients with renal and respiratory failure undergoing continuous venovenous haemofiltration. Mean (SD) clearances of atracurium and laudanosine in the haemofiltrate fluid were 0.11 (0.06) ml kg-1 min-1 and 0.09 (0.02) ml kg-1 min-1, respectively whilst plasma clearances were atracurium 6.7 (1.8) ml kg-1 min-1 and laudanosine 4.5 (1.8) ml kg-1 min-1. There were no significant differences between the plasma clearances of the drugs in the two groups, despite the difference in severity of sickness. Urinary clearance rates of atracurium and laudanosine were approximately 8 and 9% of that in the plasma, but the haemofiltration clearance of both substances was only 2%.

Maternal venous (MV), umbilical venous (UV) and umbilical arterial (UA) blood samples were obtained for assay of atracurium, laudanosine and monoquaternary alcohol concentrations in 22 healthy patients undergoing elective Caesarean section under general anaesthesia. At delivery (at a mean time of 8.2 min after atracurium 0.3 mg kg-1), the mean UV concentrations were 103 ng ml-1 (range 44-189 ng ml-1) for atracurium, 26 ng ml-1 (range 6-60 ng ml-1) for laudanosine and 59 ng ml-1 (range 21-148 ng ml-1) for monoquaternary alcohol. The ratios of UV:MV, UA:MV and UA:UV blood concentrations were related positively to time since injection of atracurium for all three substances (P less than 0.01 in each instance). The UV:MV ratio at delivery was greatest for laudanosine: mean 19.4% (range 1-35%), compared with 7% (range 2-21%) for atracurium and 10% (range 0-15%) for monoquaternary alcohol. These low values confirm that, although atracurium crosses the placental barrier and its metabolites may be found in the fetus, the drug is safe to use during Caesarean section.

The effect of pretreatment with suxamethonium, gallamine or pancuronium on suxamethonium-induced fasciculations and myalgia was studied in a controlled, randomized and double-blind clinical trial. Both fasciculations and myalgia were assessed on a four-point rating scale. There was no significant correlation between fasciculations and postoperative muscle pain at 24, 48 or 72 h, and pretreatment with suxamethonium had no significant effect on fasciculations or myalgia. Gallamine had a more marked effect on fasciculations than pancuronium, and the decrease in the fasciculation score was statistically significant. In contrast, pancuronium had a greater effect on myalgia, and decreased postoperative muscle pain significantly at 24 and 48 h. These differences may reflect the differential activity of gallamine and pancuronium at the neuromuscular junction. Pretreatment had little or no effect on plasma potassium concentrations.