Tidal volume delivery during continuous chest compressions and sustained inflation.

OBJECTIVE: To determine the distending pressure needed to achieve sufficient tidal volume (VT ) delivery during continuous chest compressions (CC) superimposed by sustained inflation (SI) (CC+SI).

DESIGN: Randomised animal/manikin trial.

SETTING: University laboratory.

SUBJECTS: Cadaver piglets/manikin.

INTERVENTIONS: SI distending pressures of 5, 10, 15, 20, 25 and 30 cm H2 O were delivered in random order during CC+SI for 2 min each.

MAIN OUTCOME MEASURES: VT , gas flow and airway pressure. Spearman's r for distending pressure and VT .

RESULTS: Distending pressure and VT correlated in cadaver piglets (r=0.83, p<0.001), manikin (r=0.98, p<0.001) and combined data (r=0.49, p<0.001). VT was delivered during chest recoil during CC in both models. In cadaver piglets, a distending pressure ∼25 cm H2 O was needed to achieve an adequate VT .

CONCLUSIONS: Chest recoil generates VT depending on an adequate distending pressure. This has previously been demonstrated in adult animals. A pressure of ∼25 cm H2 O is needed to achieve an adequate VT delivery.