Society of Obesity and Bariatric Anaesthesia publishes 43 recommendations to improve the safety and efficacy of airway management in patients living with obesity

The UK’s Society of Obesity and Bariatric Anaesthesia (SOBA) has published 43 recommendations which cover a number of key areas of practice including: pre-assessment; planning; peroxygenation; tracheal intubation; supraglottic airway devices; tracheal extubation; training; and organisational responsibilities.

The recommendations are the result of an expert multidisciplinary working party, convened on behalf of the Society, which carried out a systematic review performed followed by a three-round Delphi process. It is hoped the recommendations will improve the safety and efficacy of airway management in patients living with obesity. However, they are not intended to replace current airway management guidelines. The recommendations are endorsed by the All Wales Airway Group, Scottish Airway Group and Difficult Airway Society.

The consensus recommendations were developed by an eight-member working group on behalf of SOBA. The group comprised consultant anaesthetists (including SOBA representatives and advanced airway experts); two patient representatives; an operating department practitioner; and a resident anaesthetist.

To inform recommendations, a systematic review was performed and identified 46 studies that were included in the review. An initial list of 50 recommendations were proposed by the Working Group, with each recommendation voted on anonymously by all members of the Working Group as either ‘include’, ‘exclude’ or ‘revise’, as well as whether each recommendation should be made a top recommendation. All members participated in all rounds. Recommendations supported by ≥ 75% of the group at the end of round 2 were included in this final document. Seven recommendations with 50–74% acceptance proceeded to a third and final round of discussions. The recommendations include:

Pre-operative assessment

• All patients living with obesity should have their airway pre-assessed formally in advance of surgery (Grade D, strong recommendation).

• Patients should be consented for obesity-related complications including (but not limited to) airway difficulties (Grade D, strong recommendation).

• Patients may benefit from a face-to-face appointment with an anaesthetist in advance of elective surgery (Grade D, strong recommendation).

• Pre-assessment discussions should use patient-first language, minimising the use of medical jargon (Grade D, strong recommendation).

• Patients on CPAP/non-invasive ventilation should be instructed to bring their machine on the day of surgery (Grade C, strong recommendation).

Planning

• Operating theatre lists should flag patients with a BMI > 40 kg.m-2 (Grade D, strong recommendation).

• Additional time should be allocated for patients living with obesity when operating theatre list planning (Grade D, strong recommendation).

• Location of anaesthesia should be considered, particularly in emergencies. Appropriate equipment and personnel should be made available where out-of-theatre tracheal intubation is required (Grade D, strong recommendation).

• The BMI of patients and any anticipated difficulties should be discussed at the team brief (Grade D, strong recommendation).

• The detailed airway management strategy, including rescue strategies in the event of difficulty, should be discussed by the anaesthetic team before induction of anaesthesia (Grade D, strong recommendation).

• If there is any suggestion that your airway strategy may end up at plan D (emergency front-of-neck airway) alternative techniques including awake tracheal intubation and regional anaesthesia must be considered, and a risk–benefit decision on proceeding should be made on an individual patient basis (Grade D, strong recommendation).

• Ergonomics, including operating theatre and equipment layout, should be considered (Grade D, strong recommendation).

• Equipment necessary for anaesthetic modification should be discussed at the latest at the team brief (Grade D, strong recommendation).

• Devices to assist manual handling should be considered (e.g. hover mattress/slide sheets) (Grade D, strong recommendation).

• Devices to assist patient positioning should be considered (e.g. Oxford HELLP pillow) (Grade C, strong recommendation).

• Equipment to secure patients on the operating table safely should be available and appropriate (Grade D, strong recommendation).

• The operating table should be checked for weight limitations before the team brief (Grade D, strong recommendation).

• Ultrasound-guided identification and marking of the cricothyroid membrane, or cricoid cartilage if using cricoid force, for rapid sequence induction and tracheal intubation may be considered before induction of anaesthesia (Grade C, strong recommendation).

Facemask ventilation and peroxygenation

• Patients should be pre-oxygenated in a ramped, ≥ 30° head-up position, preferably in the operating theatre (Grade A, strong recommendation).

• Pre-oxygenation should start as soon as is practically possible (Grade D, strong recommendation).

• Facemask ventilation in patients with a high BMI is more likely to be difficult. The use of adjuncts, two-person techniques and SADs may be helpful (Grade C, strong recommendation).

• The addition of oxygenation techniques via nasal cannula (high- or low-flow) alongside facemask may confer benefits and delay desaturation (Grade A, strong recommendation).

• Consider use of HFNO as a first-line method for peroxygenation (pre-oxygenation and apnoeic oxygenation) (Grade D, strong recommendation).

• If not using an apnoeic oxygenation technique, the use of a SAD to facilitate ventilation between facemask pre-oxygenation and tracheal intubation attempts is safe and effective (Grade D, strong recommendation).

Tracheal intubation

• Basal collapse atelectasis occurs early and should be anticipated (Grade C, strong recommendation).

• A videolaryngoscope should be used as a first-line technique (Grade A, strong recommendation), preferably with a hyperangulated blade where the user is sufficiently trained (Grade C, strong recommendation).

• Ensure adequate neuromuscular blockade before tracheal intubation (Grade B, strong recommendation).

• Consider use of appropriate airway adjuncts (such as a stylet or bougie) and rescue techniques where difficulty during tracheal intubation is encountered (Grade B, strong recommendation).

• Awake tracheal intubation techniques are safe and effective in patients living with obesity but may be more challenging due to the physiological and anatomical changes. While obesity alone (in the absence of other factors) is rarely an indication for awake tracheal intubation, we recommend maintaining a low threshold for awake tracheal intubation in this group of patients (Grade D, strong recommendation).

• Tracheal intubation in the operating theatre on the operating table rather than the anaesthetic room is recommended as this minimises the need for manual handling, allows correct positioning and negates the need for ventilator disconnection and the transfer from anaesthetic room to operating theatre (Grade D, strong recommendation).

• Use of a step during tracheal intubation should be considered in order to maintain the ramped patient position (Grade D, strong recommendation).

Supraglottic airway devices

• Supraglottic airway devices may be used to provide ventilation before tracheal intubation or between attempts at tracheal intubation, to maintain oxygenation when facemask ventilation is difficult (Grade D, moderate recommendation).

• If planning to use a SAD as the primary airway device, a second-generation device should be used, ensuring head-up positioning of the patient throughout and a plan for tracheal intubation should complications arise (Grade B, strong recommendation). Use of a controlled ventilation mode may also be considered (Grade D, moderate recommendation).

Tracheal extubation

• Tracheal extubation is an elective procedure and must be planned for appropriately. This includes a plan for re-intubation of the trachea when required (Grade D, strong recommendation).

• Before tracheal extubation, patients should be pre-oxygenated with a high inspiratory fraction of oxygen, positioned in a head-up position, with adequate reversal of neuromuscular blocking drugs confirmed using quantitative neuromuscular monitoring (Grade C, strong recommendation).

• Consider tracheal extubation directly onto HFNO/CPAP in patients who are deemed at increased risk of desaturation (Grade B, strong recommendation).

• Ensure appropriate equipment and personnel are available for re-intubation of the trachea, if required (Grade D, strong recommendation).

• Postoperative destination should be considered at the earliest opportunity to enable advanced planning, specifically suitability and need for level 2 support, if the patient is known to have, or there is a high suspicion of, OSA (Grade D, strong recommendation).

Organisational responsibilities and training

• Staff should be supported to attain and maintain competencies to manage patients living with obesity (Grade D, strong recommendation).

• Organisations should have guidelines in place for the management of patients with BMI > 40 kg.m-2 (Grade D, strong recommendation).

• Organisations should have a departmental obesity lead (Grade D, strong recommendation).

• Organisations should ensure provision of suitable equipment to ensure safe and effective management of patients living with obesity (Grade D, strong recommendation).

• Resident anaesthetists should receive specific training in anaesthesia for patients living with obesity. They should be supervised appropriately, according to their level of training and clinical competency (Grade D, strong recommendation).

“More research is needed in airway management in patients living with obesity. However, the current focus is to ensure patient safety and to prevent patient harm,” the paper concludes. “The Society of Obesity and Bariatric Anaesthesia will continue to promote best practice care in all aspects of anaesthesia for patients living with obesity and will continue to collaborate with all interested groups and societies to achieve these goals.”

The findings were featured in the paper, ‘Airway management in patients living with obesity: best practice recommendations from the Society for Obesity and Bariatric Anaesthesia’, published in the journal Anaesthesia. To access this paper, please click here