DAS Small Grants

Mater Misericordiae University Hospital, Dublin

Title
To determine the optimal endotracheal tube diameter for cricothyroidotomy and to assess the effect of the tracheal hook on cricothyroid membrane height

Amount
£2,947

Scientific Abstract
In a CICO situation, the current first line DAS Guidelines advocate a scalpel, bougie, tube approach with a 6mm ID ETT.(1) A number of recent studies using stored CT images have shown that in an adult population that the height of the cricothyroid membrane may be as little as 4.7 mm (female) or 5.4 mm (male) and therefore the recommended tube size may not be appropriate to all.(2,3) Because there is a joint at the junction to the cricoid and thyroid cartilages and hinging or rotational movement is feasible at this joint when the CTM is incised, we propose to evaluate whether the currently recommended ETT tube may fit small CTM apertures. We hypothesize that this will be possible because of hinging at the joint. We propose a two-phase study using animal tracheas in which (1) the maximum diameter ETT tube will be determined by sequential insertion of increasing diameter ETT via standardized CTM incision.(2) A blinded study will be performed using the previously determined ETT size where participants are randomized to the DAS technique or tracheal hook assisted technique. The latter phase intends to determine whether the hook will increase CTM height and facilitate ETT access.

Royal United Hospital Bath

Title
'Obese neck' training manikin project

Amount
£4,632 - the AAGBI agreed to fund this project

Scientific Abstract

Background
Establishing an emergency front of neck airway (eFONA) is unsuccessful in the majority cases where it is attempted (1), with patients reported to NAP4 being twice as likely to be obese and four times as likely to be morbidly obese than the general population (1). Patients with difficult airways have, on average, an increased skin-membrane distance at the cricothyroid membrane (2). Despite this, training manikins used in airway workshops mimic patients with a 'slim neck,' rather than an obese neck. Pork belly has been shown to simulate an obese neck, but this is impractical for general use (3). We will evaluate a new commercially produced manikin which mimics the neck of an obese patient, and compare it to the slim neck manikin and the "pork belly" manikin, to improve eFONA training and improve patient safety.

Methods
Consultant and permanent members of the anaesthetic department will be asked to manage a 'cannot intubate, cannot oxygenate' situation involving each of the three training manikins, with equipment provided in accordance with the Difficult Airway Society 2015 guidelines for the management of this situation. The participants will be compared across their three manikin attempts, with investigators recording the time to first effective ventilation. After the eFONA attempts, the participant will be asked to give feedback on each of the manikins.

References
1. 4th National Audit Project of the Royal College of Anaesthetists and The Difficult Airway Society - Major complications of airway management in the UK. March 2011. Full report: www.rcoa.ac.uk/nap4 (Accessed Sept. 2017).
2. Erzi T, Gewurtz G, Sessler DI, et al. Prediction of difficult laryngoscopy in obese patients with ultrasound quantification of anterior neck soft tissue. Anaesthesia 2003; 58: 1101-8.
3. Howes TE, Lobo CA, Kelly FE, Cook TM. Rescuing the obese or burned airway: are conventional training manikins adequate? A simulation study. British Journal of Anaesthesia 2015; 114: 136-142.

Royal Surrey County Hospital

Title
Comparative study evaluating cricothyroidotomy part-task simulation trainers

Amount
£4,328

Scientific Abstract
TBC