Effect of raised alveolar pressure on leukocyte retention in the human lung.

To determine whether an increase in alveolar pressure delays the passage of leukocytes (WBCs) through the lung by compressing the lung capillaries, we measured the concentration of WBC across the lung in response to a forced expiratory maneuver. In 20 human subjects, blood was sampled from catheters placed in the pulmonary artery (PA) and left ventricle (LV) before, during, and after a forced expiratory maneuver held for greater than or equal to 20 s against an occluded airway. Pressures were recorded at the mouth and from both catheters. A significant fall in LV WBC (P less than 0.01) but not in PA WBC occurred during or immediately after the maneuver in 18 subjects, with a mean maximum decrease of 26 +/- 12% (SD) from base line (range 9-46%). Between 1 and 3 min after the maneuver, there was an increase in LV and PA WBC (P less than 0.01) above base line. The neutrophil and lymphocyte counts showed similar changes, but erythrocyte and platelet counts remained unchanged. The degree of fall in LV WBC correlated closely (r = 0.68, P less than 0.01) with the changes from lung zone 3 to zone 2 and 1 conditions, as determined from the pressure changes. We conclude that WBCs are retained in the lung during a forced expiratory maneuver because of alveolar capillary compression.

Percutaneous balloon valvuloplasty for aortic stenosis: improved quality of life for elderly patients.

From September 1986 to September 1987 percutaneous balloon valvuloplasty was performed in 20 patients with critical aortic stenosis. The mean age was 74, range 54 to 90 years. Two patients were NYHA class II, 10 patients were functional class III and eight were class IV. After percutaneous balloon valvuloplasty, using 15, 18 or 20 mm diameter balloon catheters via a 14F vascular sheath from the femoral artery, one patient was class I, 11 class II and seven were class III. One patient, who had only minimal reduction of aortic valve gradient from 120 to 100 mmHg, remained in class IV. The systolic gradient was reduced by 50% from 70 +/- 26 (+/- SD) to 35 +/- 22 mmHg (P less than 0.001) after valvuloplasty and the aortic valve area increased by 43% from 0.51 +/- 0.12 to 0.73 +/- 0.25 cm2 (P less than 0.001). There were no procedural or 30 day deaths nor any embolic events. Percutaneous balloon valvuloplasty is a relatively safe and effective treatment for the older adult with symptomatic aortic stenosis.

The structure and function of the pulmonary vasculature in mild chronic obstructive pulmonary disease. The effect of oxygen and exercise.

The structure and function of the pulmonary circulation was investigated in 17 patients requiring pulmonary resection. All 17 performed pulmonary function tests and 13 underwent right heart catheterization preoperatively. The surgical specimens of the lung were analyzed with respect to the severity of the emphysema, the severity of the airways disease, and the hypertensive changes in the small pulmonary arteries and arterioles. The data show that pulmonary artery (Ppa) and pulmonary artery wedge (Ppaw) pressures and cardiac output were normal at rest. However, patients with more severe disease showed greater increases in Ppa and Ppaw with exercise than did patients with minimal or no disease. Oxygen breathing had no effect at rest but lowered Ppa and Ppaw during exercise in the patients with more severe disease. Histologic studies showed that greater degrees of emphysema and small airways disease were associated with hypertensive changes in the pulmonary vasculature. We conclude that patients with moderate obstructive lung disease have elevated pulmonary vascular pressures during exercise and structural changes in the pulmonary arteries consistent with pulmonary hypertension when compared with patients with minimal or no disease. Although there are several possible explanations for the increased vascular pressures seen with exercise, we favor gas trapping leading to increased alveolar and pleural pressures, with oxygen breathing preventing this response by shortening the time constants of the peripheral lung units.

Complications of coronary arteriography.

In a prospective study of coronary arteriography with Judkins' technique the rate of major complications in 713 patients was 2.1%, a rate similar to or lower than those reported from other studies, even though more major complications were considered in this study. No deaths occurred. Although the rate of "other" complications was noted as part of the quality care survey, it cannot be compared with that in other studies, since the latter did not consider events such as hematoma or incomplete catheterization. The low complication rate may be related to expeditious procedures, familiarity with the Judkin's technique and the operators' experience. Local quality care assessment or clinical review committees should formally evaluate the complication rates for operative and invasive procedures performed in their own institutions.