Efficacy of ventilation and ventilation adjuncts during in-water-resuscitation—A randomized cross-over trial

Abstract

IntroductionDrowning is a common cause of death in young adults. The 2010 guidelines of the European Resuscitation Council call for in-water-resuscitation (IWR). There has been controversy about IWR amongst emergency and diving physicians for decades. The aim of the present study was assessing the efficacy of IWR. MethodsIn this randomized cross-over trial, nineteen lifeguards performed a rescue manoeuvre over a 100m distance in open water. All subjects performed the procedure four times in random order: with no ventilation (NV) and transportation only, mouth-to-mouth ventilation (MMV), bag-mask-ventilation (BMV) and laryngeal tube ventilation (LTV). Tidal volumes, ventilation rate and minute-volumes were recorded using a modified Laerdal Resusci Anne manikin. Furthermore, water aspiration and number of submersions of the test mannequin were assessed, as well as the physical effort of the lifeguard rescuers.One lifeguard subject did not complete MMV due to exhaustion and was excluded from analysis. ResultsNV was the fastest rescue manoeuvre (advantage ∼40s). MMV and LTV were evaluated as efficient and relatively easy to perform by the lifeguards. While MMV (mean 199ml) and BMV (mean 481ml) were associated with a large amount of aspirated water, aspiration was significantly lower in LTV (mean 118ml). The efficacy of ventilation was consistently good in LTV (Vt=447ml), continuously poor in BMV (Vt=197) and declined substantially during MMV (Vt=1019ml initially and Vt=786ml at the end). The physical effort of the lifeguards was remarkably higher when performing IWR: 3.7 in NV, 6.7 in MMV, 6.4 in BMV and 4.8 in LTV as measured on the 0–10 visual analogue scale. ConclusionIWR in open water is time consuming and physically demanding. The IWR training of lifeguards should put more emphasis on a reduction of aspiration. The use of ventilation adjuncts like the laryngeal tube might ease IWR, reduce aspiration of water and increase the efficacy of ventilation during IWR.