[Determination of regional extravascular lung water in heart failure]

The measurement of regional extravascular lung water (rELW) was evaluated by two double-indicator dilution methods both in normals and in patients with congestive heart failure. 1. Time-activity curves in various regions of the lungs were recorded with a positron camera (Cycl. Corp., model 4200) following a bolus application (H2O-15 as a diffusible and CO-15-Carboxyhemoglobin as an intravascular tracer). The mean transit times were computed and the extravascular lung water per unit of plasma volume (ELW/Vp was calculated. Investigations in 4 normals (ELW/Vp = 0.10-0.37, means = 0.22) and 7 patients (ELW/Vp = 0.08-0.57, means = 0.33) showed that due to constraints in the method a clinically useful index of rELW is not yielded with this particularly technique. 2. Total lung water (constant infusion of H2O-15), blood volume (single breath inhaled C-11-O), and extravascular lung water (ELW = total lung water - blood volume) were measured with a positron camera system under steady state conditions. This study showed a relatively homogenous distribution of rELW in 2 normals (0.10-0.14 g/cm3), whereas in 2 patients with congestive heart failure (NYHA III-IV) rELW was about twice as high as in normals and showed significant regional differences (0.17-0.34 g/cm3).