Right ventricular function in COPD patients during weaning from mechanical ventilation.

We studied the right ventricular function during a successful weaning period in 7 COPD patients without LV disease who had been mechanically ventilated for several days after an acute exacerbation of their disease. A Swan-Ganz ejection fraction thermodilution catheter performed measurements of right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) before and fifteen minutes after disconnection from the ventilator at the maintenance FiO2. Although pulmonary artery pressure (PAP) rose from 25 +/- 4 to 28.5 +/- 4.5 mmHg after disconnection from the ventilator, RVEF (0.36 +/- 0.56 to 0.35 +/- 0.12) and RVEDVI (117 +/- 51 to 126 +/- 52 ml/m2) remained similar in both conditions. We concluded that right ventricular systolic function assessed with modified pulmonary artery catheter was maintained during the weaning phase in such weanable patients. This method could easily detect any fall of RVEF or diastolic RV enlargement able to impair the weaning in some patients.