Expiratory positive airway pressure in postoperative cardiac hemodynamics.

BACKGROUND

[Corrected] Expiratory positive airway pressure (EPAP) is used in after cardiac surgeries. However, its hemodynamic effects have not been clearly studied.

OBJECTIVE

To evaluate the hemodynamic changes caused by EPAP in patients after cardiac surgery monitored by Swan-Ganz.

METHODS

Patients at the first or second cardiac surgery postoperative period hemodynamically stable with a Swan-Ganz catheter were included in the study. They were assessed at rest and after using 10 cmH2O EPAP at random. The variables studied were: oxygen saturation, heart rate and respiratory rate, mean artery pressures and pulmonary artery mean pressures (MAP and PAMP), central venous pressure (CVP) and pulmonary capillary wedge pressure (PAOP), cardiac output and index, and systemic and pulmonary vascular resistances. Patients were divided into subgroups (with ejection fraction <; 50% or > 50%) and data were compared by t test and ANOVA.

RESULTS

Twenty-eight patients were studied (22 men, aged 68 ± 11 years). Comparing the period of rest versus EPAP, the changes observed were: PAOP (11.9 ± 3.8 to 17.1 ± 4.9 mmHg, p < 0.001), PVC (8.7 ± 4.1 to 10.9 ± 4.3 mmHg, p = 0.014), PAMP (21.5 ± 4.2 to 26.5 ± 5.8 mmHg, p < 0.001), MAP (76 ± 10 for 80 ± 10 mmHg, p = 0.035). The other variables showed no significant differences.

CONCLUSION

EPAP was well tolerated by patients and the hemodynamic changes found showed an increase in pressure measurements of right and left ventricular filling, as well as mean arterial pressure.