Assessment of cardiopulmonary alterations in endotoxic shock.

Using radionuclide first-pass technique, seven sheep were studied prior to and during endotoxic shock. In vitro labeled 99mTC red blood cells were used to measure right and left ventricular ejection fractions (RVEF and LVEF) and cardiopulmonary transit time (CPTT) prior to and at 1, 4, 30, and 60 minutes after the intravenous injection of endotoxin Escherichia coli, 3 mg/kg bodyweight. The LVEF decreased slightly from 51 to 42% but became normal four minutes later, while the RVEF remained decreased from 49 to 26% for 60 minutes. The CPTT was prolonged from 13 to 26 cardiac beats. The decrease in RVEF was well correlated with the prolongation of the CPTT.