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Noninvasive radiographic techniques have provided a means of studying the natural history and pathogenesis of cardiovascular performance in acute and chronic respiratory failure. Chest radiography, radionuclide angiocardiography and thallium-201 imaging, and M mode and cross-sectional echocardiography have been employed. Each of these techniques has specific uses, attributes and limitations. For example, measurement of descending pulmonary arterial diameters on the plain chest radiograph allows determination of the presence or absence of pulmonary arterial hypertension. Right and left ventricular performance can be evaluated at rest and during exercise using radionuclide angiocardiography. The biventricular response to exercise and to therapeutic interventions also can be assessed with this approach. Evaluation of the pulmonary valve echogram and echocardiographic right ventricular dimensions have been shown to reflect right ventricular hemodynamics and size. Each of these noninvasive techniques has been applied to the study of patients with respiratory failure and has provided important physiologic data.

Fourteen patients with chronic obstructive pulmonary disease, mild to moderate pulmonary hypertension, and diminished right ventricular (RV) ejection fraction were studied acutely with use of a combined radionuclide-hemodynamic approach to assess and contrast the effects of 3 vasodilators on RV performance and central hemodynamic function. Nitroglycerin significantly decreased mean right atrial pressure, RV end-diastolic volume index, mean pulmonary artery pressure, cardiac index, and arterial oxygen tension, but did not affect pulmonary vascular resistance index and increased RV ejection fraction. Nitroprusside had similar effects on mean right atrial pressure, RV end-diastolic volume index, mean pulmonary artery pressure, cardiac index, and arterial oxygen tension, but also mildly decreased pulmonary vascular resistance index and did not alter RV ejection fraction. In contrast, hydralazine decreased pulmonary vascular resistance index and increased cardiac index and RV ejection fraction. The increase in ejection fraction correlated well with the decrease in pulmonary vascular resistance. These data suggest that in patients with mild to moderate secondary pulmonary hypertension, acute administration of hydralazine results in a substantial improvement in RV performance by virtue of decreasing pulmonary vascular resistance. In contrast, nitroglycerin and nitroprusside demonstrate predominant effects that reduce preload, cardiac index, and arterial oxygen tension. Based on these data, afterload reduction with vasodilators such as hydralazine may be potentially useful in selected patients with pulmonary disease and secondary pulmonary hypertension and appear preferable to agents that primarily reduce preload. Further long-term studies are necessary to establish therapeutic efficacy.

Twenty-four cases of Hemophilus influenzae pneumonia diagnosed by positive blood or pleural fluid cultures are compared to 43 cases previously reported in the literatrue. Frequently associated illnesses in both series include alcoholism, chronic airways obstruction and preceding respiratory tract infection. Moderate temperature elevation and slight leukocytosis were common on admission in both groups. Chest roentgenograms in our series revealed both bronchopneumonia (75 per cent) and lobar consolidation (38 per cent). Pleural disease occurred frequently, with two empyemas noted on admission and nine additional effusions developing during therapy. Treatment of choice was ampicillin. All five patients who did not receive ampicillin died, whereas 16 to 19 who received this drug survived. High mortality (33 per cent) in our series may be attributed to the advanced age of the patients and the presence of associated illnesses. In addition, a 10 year review suggests a true increase in the incidence of H. influenzae pneumonia in adults.

Cytotoxic drugs, principally bleomycin, methotrexate and busulfan, have been associated with pulmonary toxicity. Cytotoxic drug-induced lung disease may be difficult to establish with certainty because other causes of pulmonary disease are frequently present. We discuss the clinical, roentgenographic and histologic effects of the administration of bleomycin, methotrexate, busulfan and other cytotoxic agents on the lungs and suggest that these agents may also cause pulmonary malignancies. We note the importance of careful patient monitoring and withdrawal of a demonstrated offending agent.

A reproducible noninvasive technique for measuring righ ventricular ejection fraction was developed using first pass quantitative radionuclide angiocardiography. Studies were obtained in the anterior position with a computerized multicrystal scintillation camera with high count rate capabilities. Right ventricular ejection fraction was calculated on a beat to beat basis from the high frequency components of the background-corrected right ventricular time-activity curve. In 50 normal adults, right ventricular ejection fraction averaged 55 percent (range of 45 to 65 percent). This radionuclide measure of right ventricular function was reproducible, with minimal inter- and intraobserver variability, and was sensitive to changes in inotropic state induced with isoproterenol. In 36 patients with chronic obstructive pulmonary disease, right ventricular ejection fraction ranged from 19 to 71 percent. All 10 patients with corpulmonale, as well as 9 additional patients, had an abnormal right ventricular ejection fraction. Arterial oxygen tension and forced expiratory volume were depressed significantly more in patients with abnormal right ventricular ejection fraction than in subjects with normal right ventricular function. There was no relation between abnormalities in right and left ventricular ejection fraction.

Because right ventricular ejection fraction (RVEF) depends on impedance to RV ejection, the hypothesis was tested that an abnormality in radionuclide-determined RVEF would be a useful noninvasive predictor of pulmonary artery (PA) hypertension in patients with chronic obstructive pulmonary disease (COPD). Simultaneous measurements of resting RVEF and PA pressure were made in 30 patients with COPD. All were stable and without clinical evidence of respiratory decompensation or congestive heart failure. Eleven patients had normal (less than 20 mm Hg) mean PA pressure and 19 patients had PA hypertension. The average RVEF was 41 +/- 7% (range 29 to 60%). Five patients had normal (greater than 45%) and 25 patients depressed RVEF. An inverse linear relation between mean PA pressure and RVEF was present (r = -0.74). In the group with normal PA pressure, RVEF averaged 48% (range 42 to 60%). In the group with PA hypertension, RVEF averaged 36% (range 29 to 44%). RVEF was significantly higher in the group with PA hypertension. Using RVEF less than 45% as an indicator of PA hypertension, the sensitivity was 100%, the specificity 55%, and the predictive accuracy of a positive result 79%. Using RVEF less than or equal to 40% as an indicator of PA hypertension, the sensitivity was 75%, the specificity 100%, and the predictive accuracy of a positive study 100%. Thus, radionuclide-determined RVEF using the first-pass technique and a multicrystal camera is a useful noninvasive test for diagnosing PA hypertension in patients with advanced COPD.

Using a combined hemodynamic and radionuclide technique, 20 patients with varied ventricular function were evaluated during positive end-expiratory pressure (PEEP) application. Left ventricular (LV) and right ventricular (RV) ejection fractions and cardiac output were measured, and ventricular volumes were derived. Seven patients (group 1) who had an increase in LV end-diastolic volume with PEEP and 13 patients (group 2) who had the more typical response, a decrease in LV end-diastolic volume with PEEP, were identified. Compared with group 2, group 1 patients had a higher incidence of coronary artery disease (5 of 7 vs 1 of 13, p less than 0.005) and lower cardiac output (3.9 +/- 1.6 vs 9.1 +/- 3.2 liters/min, p less than 0.005), LV ejection fraction (27 +/- 13 vs 51 +/- 21%, p less than 0.05), RV ejection fraction (15 +/- 6 vs 32 +/- 8%, p less than 0.005) and peak filling rate (1.32 +/- 0.43 vs 3.51 +/- 1.70 end-diastolic volumes/s, p less than 0.05). LV and RV volumes increased and peak filling rate decreased with PEEP in group 1, whereas in group 2 LV volume decreased and RV volume and peak filling rate remained unchanged. Using stepwise regression analysis, the change in LV volume with PEEP was related directly to baseline systemic vascular resistance and inversely to baseline blood pressure. Similarly, the change in peak filling rate with PEEP was inversely related to the change in RV end-diastolic volume. Thus, the hemodynamic response to PEEP is heterogeneous and may be related to LV ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Thirty-six patients with diverse baseline right ventricular function were evaluated during incremental positive end-expiratory pressure (PEEP) application. Right heart pressures, cardiac output, right ventricular ejection fractions, and ventricular volumes were obtained at each PEEP level. Right ventricular peak systolic pressure-end-systolic volume relations were analyzed as an index of contractile function. Patients with severely depressed baseline right ventricular ejection fractions (30 percent or less) had an increase in end-diastolic (270 +/- 74 to 391 +/- 76 ml, 0 to 20 cm water (H2O) PEEP, p less than 0.05) and end-systolic volumes (210 +/- 70 to 321 +/- 70 ml, 0 to 20 cm H2O PEEP, p less than 0.05). These patients also had a decline in estimated right ventricular contractile function at 20 cm H2O PEEP as estimated by the slope of systolic pressure-volume relations (0.12 to 0.04 mm Hg/ml, 0 to 15 and 15 to 20 cm H2O PEEP, respectively, p less than 0.05). Patients with normal (40 percent or more) or moderately depressed (31 to 40 percent) baseline right ventricular ejection fractions had no change in right ventricular volumes or estimated contractile function. Therefore, the effect of PEEP on right ventricular function differs depending on the baseline right ventricular ejection fraction.