Obstetric Anaesthetists' Association and Difficult Airway Society guidelines for the management of difficult and failed tracheal intubation in obstetrics.

The Obstetric Anaesthetists' Association and Difficult Airway Society have developed the first national obstetric guidelines for the safe management of difficult and failed tracheal intubation during general anaesthesia. They comprise four algorithms and two tables. A master algorithm provides an overview. Algorithm 1 gives a framework on how to optimise a safe general anaesthetic technique in the obstetric patient, and emphasises: planning and multidisciplinary communication; how to prevent the rapid oxygen desaturation seen in pregnant women by advocating nasal oxygenation and mask ventilation immediately after induction; limiting intubation attempts to two; and consideration of early release of cricoid pressure if difficulties are encountered. Algorithm 2 summarises the management after declaring failed tracheal intubation with clear decision points, and encourages early insertion of a (preferably second-generation) supraglottic airway device if appropriate. Algorithm 3 covers the management of the 'can't intubate, can't oxygenate' situation and emergency front-of-neck airway access, including the necessity for timely perimortem caesarean section if maternal oxygenation cannot be achieved. Table 1 gives a structure for assessing the individual factors relevant in the decision to awaken or proceed should intubation fail, which include: urgency related to maternal or fetal factors; seniority of the anaesthetist; obesity of the patient; surgical complexity; aspiration risk; potential difficulty with provision of alternative anaesthesia; and post-induction airway device and airway patency. This decision should be considered by the team in advance of performing a general anaesthetic to make a provisional plan should failed intubation occur. The table is also intended to be used as a teaching tool to facilitate discussion and learning regarding the complex nature of decision-making when faced with a failed intubation. Table 2 gives practical considerations of how to awaken or proceed with surgery. The background paper covers recommendations on drugs, new equipment, teaching and training.

Peri-operative management of the obese surgical patient 2015: Association of Anaesthetists of Great Britain and Ireland Society for Obesity and Bariatric Anaesthesia.

Guidelines are presented for the organisational and clinical peri-operative management of anaesthesia and surgery for patients who are obese, along with a summary of the problems that obesity may cause peri-operatively. The advice presented is based on previously published advice, clinical studies and expert opinion.

Difficult Airway Society Guidelines for the management of tracheal extubation.

Tracheal extubation is a high-risk phase of anaesthesia. The majority of problems that occur during extubation and emergence are of a minor nature, but a small and significant number may result in injury or death. The need for a strategy incorporating extubation is mentioned in several international airway management guidelines, but the subject is not discussed in detail, and the emphasis has been on extubation of the patient with a difficult airway. The Difficult Airway Society has developed guidelines for the safe management of tracheal extubation in adult peri-operative practice. The guidelines discuss the problems arising during extubation and recovery and promote a strategic, stepwise approach to extubation. They emphasise the importance of planning and preparation, and include practical techniques for use in clinical practice and recommendations for post-extubation care.

Nasotracheal fibreoptic intubation: a randomised controlled trial comparing the GlideRite® (Parker-Flex® Tip) nasal tracheal tube with a standard pre-rotated nasal RAE™ tracheal tube.

In a randomised controlled study, we compared the ease of railroading a GlideRite® nasal tracheal tube over a fibrescope with that of a pre-rotated RAE™ nasal tracheal tube. We studied 110 anaesthetised patients with no known airway difficulties undergoing elective dental or maxillofacial surgery. Impingement was more common with the GlideRite tubes (11/55 (20%)) compared with the pre-rotated RAE tubes (3/55 (5%); p=0.02). The median (IQR [range]) time to intubation (GlideRite 7.6 (4.7-10.8 [3.0-46.2]) s; RAE 8.0 (6.2-10.7 [2.4-30.0]) s) and postoperative sore throat numerical ratings (GlideRite 2 (0-3 [0-10]); RAE 2 (0-5 [0-8])) were similar. A 90° anticlockwise pre-rotation of a standard nasal RAE tube has a higher initial rate of successful railroading at first attempt and is therefore superior to a GlideRite nasotracheal tube during nasal fibreoptic intubation.

The Difficult Airway Society 'ADEPT' guidance on selecting airway devices: the basis of a strategy for equipment evaluation.

Faced with the concern that an increasing number of airway management devices were being introduced into clinical practice with little or no prior evidence of their clinical efficacy or safety, the Difficult Airway Society formed a working party (Airway Device Evaluation Project Team) to establish a process by which the airway management community within the profession could itself lead a process of formal device/equipment evaluation. Although there are several national and international regulations governing which products can come on to the market and be legitimately sold, there has hitherto been no formal professional guidance relating to how products should be selected (i.e. purchased). The Airway Device Evaluation Project Team's first task was to formulate such advice, emphasising evidence-based principles. Team discussions led to a definition of the minimum level of evidence needed to make a pragmatic decision about the purchase or selection of an airway device. The Team concluded that this definition should form the basis of a professional standard, guiding those with responsibility for selecting airway devices. We describe how widespread adoption of this professional standard can act as a driver to create an infrastructure in which the required evidence can be obtained. Essential elements are that: (i) the Difficult Airway Society facilitates a coherent national network of research-active units; and (ii) individual anaesthetists in hospital trusts play a more active role in local purchasing decisions, applying the relevant evidence and communicating their purchasing decisions to the Difficult Airway Society.

Clinical manifestations and outcome in HIV-infected young infants presenting with acute illness in Durban, South Africa.

OBJECTIVES: In young infants, early development of symptomatic HIV infection increases the risk of morbidity and mortality. A prospective study was conducted over a 1-year period in a region with a high burden of HIV in order to describe the clinical presentation of HIV infection in infants aged between 0 and 59 days on attendance at hospital and the factors associated with the need for urgent hospital management. METHODS: Sick young infants presenting to the King Edward VIII Hospital, Durban between February 2003 and January 2004 were enrolled. After systematic evaluation by a primary health worker, an experienced paediatrician determined the primary diagnosis and need for urgent hospital management. Comparisons of these assessments were stratified by HIV status. Children were classified as HIV-uninfected (HIV ELISA-negative), HIV-exposed-but-uninfected (HIV ELISA-positive and HIV RNA PCR-negative), HIV-infected (HIV ELISA-positive and HIV viral load >400 copies/ml). RESULTS: Of 925 infants enrolled, 652 (70·5%) had their HIV status determined: 70 (10·7%) were HIV-infected, 271 (41·6%) HIV-exposed-but-uninfected, and 311 (47·7%) HIV-uninfected. Factors associated with an increased probability of being HIV-infected included if the mother had children from more than one sexual partner, if the infant had had contact with a tuberculosis-infected person or if the HIV-infected mother and/or her exposed infant failed to receive nevirapine prophylaxis. Signs of severe illness were more frequently encountered in HIV-infected than in HIV-exposed-but-uninfected infants, including the prevalence of chest in-drawing (20·3% vs 8·8%, p = 0·004) and severe skin pustules (18·6% vs 8·6%, p = 0·01). Among infants requiring urgent hospital management, observed or reported feeding difficulties and severe skin pustules were more common in HIV-infected than uninfected infants. More HIV-infected infants (12·9%) required hospitalisation than those who were HIV-exposed-but-uninfected (7·7%) or uninfected (7·4%). Primary diagnoses of pneumonia, sepsis or oral thrush were more frequently seen in HIV-infected than exposed-but-uninfected or HIV-uninfected children. CONCLUSION: Early recognition and triaging of infants suspected of having HIV infection provides an opportunity for early diagnosis and treatment which could prevent the adverse impact of rapidly progressive HIV disease.

A comparison of a flexometallic tracheal tube with the intubating laryngeal mask tracheal tube for nasotracheal fibreoptic intubation using the two-scope technique.

We compared the incidence and site of impingement of a flexometallic tracheal tube with those of the re-usable intubating laryngeal mask (ILMA) tube in 60 anaesthetised patients undergoing nasotracheal fibreoptic intubation for oral surgery. A two-scope technique was used, observing the site of impingement with one scope whilst intubating with the other. The tubes were 6.0-mm in females and 6.5-mm in males. Impingement occurred with 10 (33%) flexometallic and 2 (7%) ILMA tubes (p < 0.032). In all but one case, the impingement was posterior to the right arytenoid cartilage. When impingement was observed, a single disempaction with a 90 degrees anticlockwise rotational manoeuvre overcame impingement in every case except one, allowing successful intubation. We conclude that the incidence of impingement of the tracheal tube, and therefore of potential laryngeal trauma from nasotracheal fibreoptic intubation, is significantly greater with the flexometallic tube than with the ILMA tube.

Regional anaesthesia for limb surgery: a review of anaesthetists' beliefs and practice in the Oxford region.

We conducted a postal survey of 210 anaesthetists in the Oxford region to determine their views and practice regarding the timing of regional anaesthesia when combined with general anaesthesia for adults undergoing limb surgery and to compare the results with those obtained in a similar survey conducted in 2001. Of the 151 respondents (72% response rate), 102 (68%) regularly combined regional and general anaesthesia for adult limb surgery. Over 80% believed that central neuraxial blocks should be performed before general anaesthesia. This matched their current practice, marking a change from 2001. Significantly fewer anaesthetists believed it necessary to perform peripheral nerve blocks before general anaesthesia than in 2001, marking another significant change in practice. Overall, the results indicate an increased popularity of regional blocks in combination with general anaesthesia when compared with 2001 practice, which we believe is related to high quality advanced training modules now on offer to senior trainees in the Oxford region.

Antenatal anaesthetic assessment of high-risk pregnancy: a survey of UK practice.

BACKGROUND: Anaesthetists are frequently involved in the management of high-risk pregnancy. Antenatal referral permits time to prepare an appropriate management plan for labour and delivery. This survey looked at current methods of referral in the UK and the role of a formal clinic. METHOD: A postal questionnaire was sent to lead consultant anaesthetists of 256 UK obstetric units enquiring into methods of referral for high-risk pregnancy. RESULTS: Replies were received from 196 units (response rate 77%). Only 30% of units that responded ran a formal anaesthetic pre-assessment clinic, the remaining 70% relying on ad hoc referrals of high-risk cases. Larger units were more likely to run formal clinics. Some units wishing to introduce a formal clinic had not been able to do so because of financial constraints. CONCLUSION: Most hospitals were satisfied with current arrangements for referral of high-risk pregnancy. A mechanism for anaesthetic referral of high-risk pregnancy is vital, but in many units is not via a formal clinic.

Failed tracheal intubation during obstetric general anaesthesia: a literature review.

We reviewed the literature on obstetric failed tracheal intubation from 1970 onwards. The incidence remained unchanged over the period at 2.6 (95% CI 2.0 to 3.2) per 1000 anaesthetics (1 in 390) for obstetric general anaesthesia and 2.3 (95% CI 1.7 to 2.9) per 1000 general anaesthetics (1 in 443) for caesarean section. Maternal mortality from failed intubation was 2.3 (95% CI 0.3 to 8.2) per 100000 general anaesthetics for caesarean section (one death per 90 failed intubations). Maternal deaths occurred from aspiration or hypoxaemia secondary to airway obstruction or oesophageal intubation. There were 3.4 (95% CI 0.7 to 9.9) front-of-neck airway access procedures (surgical airway) per 100000 general anaesthetics for caesarean section (one procedure per 60 failed intubations), usually carried out as a late rescue attempt with poor maternal outcomes. Before the late 1990s, most cases were awakened after failed intubation; since the late 1990s, general anaesthesia has been continued in the majority of cases. When general anaesthesia was continued, a laryngeal mask was usually used but with a trend towards use of a second-generation supraglottic airway device. A prospective study of obstetric general anaesthesia found that transient maternal hypoxaemia occurred in over two-thirds of cases of failed intubation, usually without sequelae. Pulmonary aspiration occurred in 8% but the rate of maternal intensive care unit admission after failed intubation was the same as that after uneventful general anaesthesia. Poor neonatal outcomes were often associated with preoperative fetal compromise, although failed intubation and lowest maternal oxygen saturation were independent predictors of neonatal intensive care unit admission.

Awake fibreoptic intubation skills in obstetric patients: a survey of anaesthetists in the Oxford region.

A survey of anaesthetists in the Oxford region was conducted to determine their skills and practice in performing awake fibreoptic intubation. Forty-two consultant obstetric anaesthetists (group O), 21 consultant anaesthetists with an interest in difficult airway management (group D) and 20 anaesthetic specialist registrars in their final training year (group S) were sent a questionnaire on management of a patient with a known difficult airway for elective caesarean section. All but one responded. If regional anaesthesia was unsuccessful or contraindicated, 75/82 respondents (91.5%) would choose to secure the airway by awake intubation. Of the remaining seven, six would use general anaesthesia and spontaneous respiration, five (6.1%) with the laryngeal mask airway and one (1.2%) with mask and airway and one (1.2%) local infiltration by the surgeon. Although awake fibreoptic intubation was the technique chosen by 98.7%, only six (8.1%) had experience of its performance in an obstetric patient. Of the 68 anaesthetists without such experience, only 12/31 (38.7%) group O compared to 13/18 (72.2%) group D and 12/19 (63.2%) group S would be confident to perform awake fibreoptic intubation in an obstetric patient. Only one anaesthetist in the survey practised awake fibreoptic intubation in non-obstetric patients regularly (>3/month). However, 69/82 respondents replied that all consultant obstetric anaesthetists should be experienced in performing awake fibreoptic intubation. We conclude that despite the value of awake fibreoptic intubation, consultant obstetric anaesthetists are less confident in performing it than those with an interest in difficult airway management and final year specialist registrars.

Combined spinal epidural anaesthesia for caesarean section: a randomised comparison of Oxford, lateral and sitting positions.

Maternal position during induction of intrathecal anaesthesia for caesarean section influences block height and haemodynamic stability. In a randomised study of 90 women presenting for elective caesarean section using combined spinal-epidural anaesthesia, three positions were compared--the Oxford position (group O), the right lateral to supine wedged (group R) and the sitting to supine wedged (group S). Hyperbaric bupivacaine 12.5 mg with fentanyl 12.5 microg was injected intrathecally using a needle-through-needle CSE technique. Intravenous ephedrine 6 mg was given every minute that systolic blood pressure fell below 80% of baseline. Time required for block height to reach T5 as assessed by light touch, was similar in the three groups. There were no significant differences in blood pressure although ephedrine requirements were less in group R. There were no significant differences in the incidence of maternal nausea and vomiting or in neonatal outcome as assessed by Apgar scores and umbilical cord blood gas analysis. Although the study failed to show any significant differences in block height between the groups, no women in group O had a block above T2 compared with three in group R and three in group S.

Epidural diamorphine for post-caesarean pain: a dose response study.

The effectiveness of postoperative pain relief and the frequency of side effects with three different doses of epidural diamorphine (2.0, 3.5 and 5 mg) was investigated. The study was carried out double-blind in 30 women undergoing awake elective caesarean section. Postoperative pain intensity was measured on a linear analogue scale. The time to onset of analgesia (TOA), time taken to reach a pain score of zero or become comfortable, and time to next analgesia (TNA) were not significantly different between groups. Three patients in the 2 mg group failed to achieve scores of zero but were comfortable. No nausea or vomiting was seen but the incidence of itching was 0, 30% and 80% in the 2.0, 3.5 and 5 mg groups respectively. We conclude that epidural diamorphine 2 mg is adequate for relief of post-caesarean pain and higher doses may increase the incidence of unwanted side-effects.

A comparison of bupivacaine-fentanyl-morphine with bupivacaine-fentanyl-diamorphine for caesarean section under spinal anaesthesia.

In a randomised double-blind trial, postoperative analgesia and side effects of intrathecal morphine 0.1 mg and intrathecal diamorphine 0.25 mg were compared. Sixty women were randomised to receive intrathecal injection of 12.5 mg hyperbaric bupivacaine and 12.5 microg fentanyl with either morphine 0.1 mg (group M), or diamorphine 0.25 mg (group D). All women received 100 mg diclofenac rectally at the end of surgery and were given intravenous morphine via a patient controlled analgesia (PCA) system. Pain, PCA morphine usage and side effects were assessed at 2, 4, 8 and 24 h after spinal anaesthesia. The two groups were comparable for quality of intraoperative analgesia. There were no significant differences between the groups in time to first PCA demand, morphine consumption or oral analgesic use in each time period. Significantly more patients in group M were nauseated at 4 h whilst at 24 h nausea was significantly worse in group D. There was no significant difference between the groups in the number of women vomiting in the 24-h period. The two groups were comparable for pruritus and drowsiness. We conclude that 0.25 mg subarachnoid diamorphine is a suitable alternative to 0.1 mg morphine for post caesarean section analgesia.