LAUSR

Background: Foreign body airway obstruction (FBAO) is a common cause of death. The European Resuscitation Society recommends treatment of FBAO in conscious adults as a combination of back blows and abdominal thrusts with no preferential order (Perkins et al, 2015). Aims: To assess the transmission of pressure across the diaphragm during different expulsive manoeuvres. Hypothesis: Regardless of placement or direction of force, pressure will be transmitted across the diaphragm, creating an expulsive force in FBOA. Methods: Five different types of expulsive manoeuvres were performed randomly on/by four consenting adult physiologists. Peak oesophageal (P oes ) and gastric (P gas ) pressures (cmH 2 O) were measured via oesophageal and gastric balloon catheters. Results: Heimlich manoeuvre P oes (Median±SD) was 57±17cmH 2 O and circumferential abdominal thrust 53±11cmH 2 O (p=0.7). Chair thrust generated a significantly higher Poes than both; 115±27cmH 2 O (p=0.008 when compared to Heimlich). Conclusions: Approaches to the management of a choking person need to be effective and timely as this is can be a life threating emergency situation. This study has found that regardless of the direction of force, pressure is transmitted to the thorax. Auto-administered thrusts appear as effective as first-aider administered ones to generate expulsive intrathoracic pressures and chair thrusts appear to be the most effective. We conclude that these manoeuvres are effective in generating expulsive intrathoracic pressures.