Bag-mask ventilation by low- or untrained rescuers during resuscitation: a randomised cross-over study

ABSTRACT

Objective: Bag-mask ventilation (BMV) forms a cornerstone during advanced cardiopulmonary resuscitation (CPR), as opposed to lay settings applying mouth-to-mouth ventilation. The latter is contraindicated in case of potential disease transmission (COVID pandemic). This study explores the degree of training needed for rescuers to effectively perform BMV during CPR. Methods: We performed a randomized crossover manikin study (Laerdal’s Resusci Anne QCPR - Resusci Baby QCPR) with 112 medical students 60 first years (untrained) and 52 fourth years (low-trained), excluding BLS certificate holders or lifeguards. After dividing students into duos within their year and a 15 minute just-in-time training in full CPR-cycle using BMV, each pair was tested during 5 cycles of 2-person CPR following the ERC guidelines. In infants, initial rescue breaths used 1-person BMV. Correct ventilations included tidal volumes of 300– 600 ml (adults) and 20–60 ml (infants). Results: Correctly administered ventilations during adult CPR using BMV showed no statistically significant difference between low- and untrained rescuers (first years 63,0%;fourth years 59,5%;proportional difference − 3.5% [−12.8;5.9]). A significant difference was observed in infant CPR, both in effective ventilations (first years 55,5%;fourth years 72,3%;proportional difference 16.8 [7.25;26.21]) and initial rescue breaths (first years 54,1%;fourth years 72,0%;proportional difference 17.9 [5.36;30.50]). Of the remaining 39 pairs after exclusion of 17 (n = 56) for incorrect numbers of ventilation or uninterpretable values, 15 duo’s (38,5%) accomplishes efficient ventilations using BMV. Comparison by year unveils 40,9% untrained rescuers performing efficient ventilations versus 35,3% low-trained rescuers. Inclusion of all 56 groups shows 27,8% performing correct ventilations. Conclusion:With 1/3 of low- and untrained participants performing effective BMV during CPR following a just-in-time training prior to testing, the difference between both groups was small, reaching significance in infant ventilations. In conclusion, 2-person BMV is a complex skill requiring sufficient and regular training