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

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.

A prospective, randomized trial.

A university-affiliated tertiary care hospital.

Cardiac surgery patients.

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.

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.

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.