Hemodynamic Consequence of Hand Ventilation Versus Machine Ventilation During Transport After Cardiac Surgery

Objectives: The hemodynamic consequences of ventilation of intubated patients during transport either by hand or using a transport ventilator have not been reported in patients after cardiac surgery. The authors hypothesized that bag-mask ventilation would alter end-tidal CO₂ during transport and hemodynamic parameters in patients post-cardiac surgery.

Design: A prospective, randomized trial.

Setting: A university-affiliated tertiary care hospital.

Participants: Cardiac surgery patients.

Interventions: Thirty-six patients were randomized to hand ventilation or machine ventilation. Hemodynamic variables including blood pressure, heart rate, peripheral saturation of oxygen, and end-tidal carbon dioxide (ETCO₂) were measured in these patients prior to transport, every 2 minutes during transport and upon arrival in the intensive care unit (ICU). Pulmonary artery pressure (PA) pressures were measured at origin and at destination.

Measurements and main results: Outcomes were changes from baseline in end-tidal CO₂, hemodynamic changes from baseline and pulmonary artery pressure changes from origin to destination. The average transport time between the 2 groups was not different: 5 minutes for patients ventilated by hand and 5.47 minutes for patients ventilated with a transport ventilator (p = 0.369 by 2-sided t-test). The difference in all measured changes in ETCO₂ between hand-ventilated and machine-ventilated patients during transport was 2.74 mmHg (p = 0.013). The difference between operating room and ICU ETCO₂ from each cohort was 1.31 mmHg (p = 0.067). The difference in PA_mean measured at origin and destination was 0.783 mmHg (p = 0.622). All other hemodynamic variables were not different during transport.

Conclusions: Hand ventilation during transport was associated with greater change from baseline of ETCO₂ compared to machine ventilation during transport after cardiac surgery, but this did not translate into any difference in hemodynamic changes upon arrival in ICU. A hemodynamic benefit of machine transport ventilation to cardiac patients was not demonstrated.