Potential Effects of Corticosteroids on Physiological Dead-Space Fraction in Acute Respiratory Distress Syndrome

• Published in: Respiratory care 2012-03, Vol.57 (3), p.377-383
• Main Authors: RAURICH, Joan M, FERRERUELA, Mireia, LLOMPART-POU, Juan A, VILAR, Margalida, COLOMAR, Asunción, AYESTARAN, Ignacio, PEREZ-BARCENA, Jon, IBANEZ, Jordi
• Format: Article
• Language: English
• Subjects: Adult; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Corticosteroids; Drug therapy; Emergency and intensive respiratory care; Female; Glucocorticoids - pharmacology; Glucocorticoids - therapeutic use; Health aspects; Humans; Intensive care medicine; Male; Medical sciences; Methylprednisolone - pharmacology; Methylprednisolone - therapeutic use; Middle Aged; Respiration, Artificial; Respiratory Dead Space - drug effects; Respiratory Dead Space - physiology; Respiratory distress syndrome; Respiratory Distress Syndrome, Adult - drug therapy; Respiratory Distress Syndrome, Adult - physiopathology; Respiratory Function Tests; Tidal Volume - physiology; Time Factors
• ISSN: 0020-1324; 1943-3654
• DOI: 10.4187/respcare.01301

Increased dead-space fraction is common in patients with persistent acute respiratory distress syndrome (ARDS). We evaluated the changes in the oxygenation and dead-space fraction in patients with persistent ARDS after corticosteroid therapy. This was a non-randomized non-placebo, controlled observational study including 19 patients with persistent ARDS treated with corticosteroids. We measured P(aO(2))/F(IO(2)) and dead-space fraction at days 0, 4, and 7 after corticosteroids treatment (methylprednisolone) initiation. Patients were classified in intermediate group when corticosteroids were initiated between days 8-14 after ARDS onset, and in late group when initiated after 14 days. Mean time from the diagnosis of the ARDS to methylprednisolone treatment was 11 ± 2 days in the intermediate group (10 patients) and 21 ± 8 days in the late group (9 patients). When comparing days 0, 4, and 7 after methylprednisolone treatment, we found an increase in the P(aO(2))/F(IO(2)) (145 ± 64 mm Hg, 190 ± 68 mm Hg, and 226 ± 84 mm Hg, respectively, P < .001) and a decrease in the physiological dead-space fraction (0.66 ± 0.10, 0.58 ± 0.12, and 0.53 ± 0.11, respectively, P < .001). No differences were found between the intermediate and late groups. In patients with persistent ARDS, the increase in oxygenation was accompanied by a decrease in the dead-space fraction after a few days of corticosteroid treatment. To confirm potential benefit of corticosteroids on physiological parameters and mortality will require a powered randomized placebo controlled trial.