Additive effect on gas exchange of inhaled nitric oxide and intravenous almitrine bismesylate in the adult respiratory distress syndrome

Abstract

Objective: To assess the additive effect of inhaled nitric oxide (NO) and intravenous almitrine bismesylate (ALM) on gas exchange. Design: Prospective self-controlled study. Setting: 3 medico-surgical intensive care units. Patients: 17 patients with severe hypoxemia (PaO2/FIO2 ratio: 88±30mmHg, venous admixture: 47±7%) and elevated mean pulmonary artery pressure (MPAP: 30±5mmHg) due to adult respiratory distress syndrome (ARDS). Interventions: 5 conditions were studied: 1) baseline, 2) 5 to 10ppm of NO during 30min, 3) discontinuation of NO during 30min, 4) ALM infusion (0.5mg/kg) during 30min, 5) ALM infusion (0.5mg/kg) during 30min in combination with 5 to 10ppm of NO. Measurement and results: The PaO2/FIO2 ratio rose from 88±30 to 98±37mmHg (NS) with NO alone, and from 92±25 to 130±56mmHg (p<0.01) with NO+ALM (p<0.05 vs NO alone). Seven patients were considered as "NO-responders" (rise in PaO2/FIO2 ratio of 10mmHg or more with NO); in this subgroup the PaO2/FIO2 ratio rose from 87±30 to 128±39mmHg (p<0.05) with NO alone, and from 93±20 to 169±51mmHg (p<0.01) with NO+ALM (p<0.05 versus NO alone). MPAP decreased from 30±5 to 26±5mmHg (p<0.01) with NO alone, increased slightly from 28±5 to 31±5mmHg (NS) with ALM alone and decreased to 27±5mmHg (p<0.05) with NO+ALM. Conclusions: NO+ALM had additive effects on gas exchange while decreasing MPAP in patients with ARDS. The effects of NO alone were small and non significant, except in a subgroup of 7 patients in whom the combination of both therapies had the more pronounced results. © 1994 Springer-Verlag.