Comparison of the Mapleson C circuit, 500 ml and 1.6 l self-inflating bags for delivering guideline-compliant ventilation during simulated adult cardiopulmonary resuscitation

Introduction

Despite all the research and education that has gone into the field of cardiopulmonary resuscitation (CPR), survival rates remain bleak. A significant problem has been the discrepancy between teachings and witnessed clinical practice. As a result of this, and the deleterious outcomes associated with hyperventilation, we conducted a manikin-based study to evaluate three different ventilating devices and their ability to provide guideline-compliant ventilation during simulated adult CPR.

Methods

A simulated cardiac arrest scenario was undertaken by 33 healthcare professionals (α = 0.05, power = 80%). Participants were asked to ventilate a simulated cardiac arrest patient for a period of 1 minute with all three devices, during which time various ventilatory parameters were recorded using a spirometer. The devices investigated were the Mapleson C circuit, adult (1.6 l) and paediatric (500 ml) self-inflating bags. P < 0.01 was deemed statistical significant, due to multiple comparisons.

Results

The paediatric self-inflating bag performed best, with significant improvement in the mean minute ventilation (P = 0.003), tidal volume (P < 0.001) and peak airway pressure (P < 0.001). Despite the significant differences, the paediatric self-inflating bag still delivered a mean minute ventilation of 7.01 l/minute, which still exceeds the Resuscitation Council's suggested 5 l/minute. See Table 1.

Table 1 Comparison of data on ventilation parameters

Conclusions

Participants were found to be hyperventilating simulated cardiac arrest patients with all devices. The paediatric self-inflating bags delivered the most guideline-compliant ventilation and its use in adult CPR may be a simple measure to ensure delivery of more guideline-consistent ventilation.