Skip to content


  • Poster presentation
  • Open Access

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

  • 1,
  • 1,
  • 1 and
  • 1
Critical Care201115 (Suppl 1) :P290

  • Published:


  • Public Health
  • Survival Rate
  • Clinical Practice
  • Emergency Medicine
  • Healthcare Professional


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.


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.


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


500 ml self-inflating bag

1.6 l self-inflating bag

Mapleson C circuit

P value

Minute ventilation (l/minute)

7.01 (3.22)

9.68 (4.22)

9.77 (3.45)


Tidal volume (nl)

391 (51.5)

582 (86.7)

625 (103)

< 0.001*

Respiratory rate (/minute)

16.7 (6.9)

18 (6.45)

17.3 (5.46)


Peak airway pressure (cmH2O)

14.5 (5.18)

20.7 (9.03)

30.3 (11.4)

< 0.001*

Data presented as mean (SD). *Statistically significant result. Nonstatistically significant result.


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.

Authors’ Affiliations

Queens Hospital, Romford, UK