17 мая 2002 00:00 |
Natriuretic peptides after pulmonary resection
Background. Little is known about alterations in the levels and influence of natriuretic peptide (NP) on cardiopulmonary function after pulmonary resection for lung cancer. This study was designed to investigate the patterns and activity of NP after pulmonary resection.
Methods. We investigated changes in plasma
A-type (atrial) NP and B-type (brain) NP (BNP) using radioimmunoassay, in lung cancer patients before and after lobectomy (n = 15) or pneumonectomy (n = 10). Patient characteristics, respiratory function, operative time, blood loss, intraoperative fluid administration, and intraoperative urine output in both groups were also compared. Pulmonary hemodynamic variables were monitored continuously.
Results. Plasma concentrations
of A-type NP and BNP did not differ between the two groups preoperatively. However, the group undergoing pneumonectomy exhibited higher concentrations of A-type NP and BNP than the group undergoing lobectomy on postoperative days 3 and 7. Alterations in A-type NP and BNP after pulmonary resection therefore differed according to the volume of lung tissue resected. Both mean pulmonary artery pressure and total pulmonary vascular resistance increased significantly in the pneumonectomy group. The total pulmonary vascular resistance on postoperative day 3 correlated with the plasma BNP concentration in the pneumonectomy group.
A-type NP and BNP effectively compensate for the right ventricular dysfunction noted after pulmonary resection, and this is more evident after pneumonectomy than after lobectomy. Changes in ventricular activity associated with changes in plasma BNP and total pulmonary vascular resistance are indicative of cardiopulmonary adjustments after pneumonectomy.