Right heart function and prediction of respiratory morbidity in patients undergoing pneumonectomy with moderately...

Detailed hemodynamic monitoring was performed in 20 patients undergoing pneumonectomy with moderately severe chronic obstructive pulmonary disease. Flow-directed pulmonary artery catheters capable of determining thermal dilution right ventricular ejection fraction and other indexes of right ventricular performance were placed in each patient. The mean actual and percent values for forced expiratory volume in 1 second in this group were 1.8 +/- 0.5 L and 66% +/- 18%, respectively. Pulmonary hypertension was present in 76.5% of patients at the baseline nonintubated state. At pulmonary artery clamping, 53.8% of this subgroup had no change or a mean drop of 8 mm Hg in pressure. The remaining had a mean rise of 12 mm Hg. Mean systolic pulmonary artery pressures in this subset (41 mm Hg) did not change from the nonintubated state to pulmonary artery clamping. Patients with normal pulmonary artery pressures before intubation had an average rise of only 4 mm Hg at pulmonary artery clamping. In the immediate postoperative period, only 10.0% of the entire group had normal pulmonary artery pressures. Right ventricular ejection fraction and pulmonary vascular resistance were normal in 58.8% and 94.1%, respectively, at the baseline nonintubated state. Abnormal right ventricular ejection fraction values (< 45%) were present in 70.0% of patients at pulmonary artery clamping; 25.0% fell below 35%. Pulmonary vascular resistance increased above 200 dyne.sec.cm-5 in 30.0% at pulmonary artery clamping. No correlation was found between right ventricular ejection fraction and pulmonary vascular resistance or pulmonary artery pressure during operation. No pulmonary function test or hemodynamic variable measured in this study accurately predicted the days of hospital stay or early postoperative cardiopulmonary morbidity. At the baseline nonintubated state, no parameter consistently predicted late New York Heart Association class III/IV. At the time of pulmonary artery clamping, a right ventricular ejection fraction of less than 35%, a pulmonary vascular resistance greater than or equal to 200 dyne.sec.cm-5, and a pulmonary vascular resistance/right ventricular ejection fraction ratio greater than or equal to 5.0 predicted the development of long-term cardiopulmonary disability. Thirteen patients (65.0%) in this series with abnormally low preoperative pulmonary function could have been excluded from pneumonectomy. Only five of 13 patients (38.5%) had late class III/IV symptoms. Four of these five patients had a right ventricular ejection fraction less than 35% during operation.(ABSTRACT TRUNCATED AT 400 WORDS)