This study was designed to test the feasibility of using the noninvasive radionuclide measurement of the right ventricular ejection fraction (RVEF) to identify which patients with chronic lung disease objectively benefit from low flow oxyhgen therapy. Two categories of benefit, pulmonary artery pressure/resistance and peripheral oxygen delivery, were examined in 19 patients. Fourteen subjects returned after at least 3 wk of continuous low flow oxygen therapy for restudy; 12 patients had complete radionuclide and hemodynamic data. The change in RVEF, in response to continuous oxygen, correlated significantly with the change in coefficient of oxygen delivery (r = 0.59, p < 0.05) and the change in cardiac output (r = 0.62, p < 0.05). The change in RVEF did not correlate significantly with the change in pulmonary artery pressure (r = 0.06) or the change in total pulmonary resistance (r = -0.35). The change in coefficient of oxygen delivery, representing oxygen delivery corrected for oxygen consumption, correlated positively with change in cardiac output (r = 0.58, p < 0.05) and negatively with change in oxygen consumption (r = -0.63, p < 0.05), arterial oxygen content (r = -0.63, p < 0.05), and arterial oxygen tension (r = -0.61, p < 0.05). That is, (1) the fall in hemoglobin in these patients more than compensated for any increase in Pa(O2) so that improved oxygen delivery frequently occurred despite a decrease in arterial oxygen content, and (2) improved oxygen delivery occurred for the most part among patients with smaller improvement in Pa(O2). On the basis of this preliminary data, the following concept is advanced: peripheral oxygen delivery in chronic lung disease is primarily a function of cardiac output and cardiac output is primarily a function of right ventricular systolic function. This study supports the possibility that the RVEF measurement by radionuclide ventriculography might allow for noninvasive, outpatient, objective assessment of continuous low flow oxygen therapy.
|Original language||English (US)|
|Number of pages||6|
|Journal||American Review of Respiratory Disease|
|State||Published - Jan 1 1986|
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine