Methylprednisolone improves pulmonary function and hemodynamics in experimental gram-positive septicemia

It has been suggested that the effects of high-dose corticosteroid therapy (HDC) in gram-positive (G+) and gram-negative (G-) septicemia differ. As few data are available on HDC in G+ septicemia, pulmonary and cardiovascular function was studied for 44 hr in five anesthetized pigs subjected to brief infusion of live Staphylococcus aureus (approximately 10(11) cfu) followed by intravenous methylprednisolone (MP, 30 mg/kg) administered as a bolus every 8 hr. Comparisons were made with six septic pigs given no MP but otherwise identically managed. Six control pigs received no bacteria or MP. Infusion of bacteria induced identical transient pulmonary hypertension in both septic groups (52 +/- 7 mm Hg, mean +/- SD), but MPAP remained significantly lower in the pigs with MP (18 +/- 1 mm Hg vs. 30 +/- 9 mm Hg at 8 hr, P less than 0.05). MAP was better maintained in the MP group (107 +/- 9 mm Hg vs. 80 +/- 16 mm Hg at 8 hr, P less than 0.05). Pulmonary function also was less affected in the MP group at 8 hr, with significantly better maintenance of arterial oxygenation (13.5 +/- 1.2 kPa vs. 9.4 +/- 2.2 kPa, P less than 0.05) less venous admixture (11 +/- 6% vs. 34 +/- 23%, P less than 0.05) and superior lung-thorax compliance (29 +/- 5 ml/cm H2O vs. 15 +/- 5 ml/cm H2O, P less than 0.05). Five of five with MP survived, whereas two of six without MP survived (P = 0.045). MP thus attenuated pulmonary and hemodynamic abnormalities induced by S. aureus septicemia.(ABSTRACT TRUNCATED AT 250 WORDS)