Exogenous pulmonary surfactant for the treatment of adult patients with acute respiratory distress syndrome: results of a meta-analysis.
BACKGROUND
The purpose of this study was to perform a systematic review and meta-analysis of exogenous surfactant administration to assess whether this therapy may be useful in adult patients with acute respiratory distress syndrome.


METHODS
We performed a computerized literature search from 1966 to December 2005 to identify randomized clinical trials. The primary outcome measure was mortality 28-30 days after randomization. Secondary outcome measures included a change in oxygenation (PaO2:FiO2 ratio), the number of ventilation-free days, and the mean duration of ventilation. Meta-analysis was performed using the inverse variance method.


RESULTS
Two hundred and fifty-one articles were identified. Five studies met our inclusion criteria. Treatment with pulmonary surfactant was not associated with reduced mortality compared with the control group (odds ratio 0.97; 95% confidence interval (CI) 0.73, 1.30). Subgroup analysis revealed no difference between surfactant containing surface protein or not - the pooled odds ratio for mortality was 0.87 (95% CI 0.48, 1.58) for trials using surface protein and the odds ratio was 1.08 (95% CI 0.72, 1.64) for trials without surface protein. The mean difference in change in the PaO2:FiO2 ratio was not significant (P = 0.11). There was a trend for improved oxygenation in the surfactant group (pooled mean change 13.18 mmHg, standard error 8.23 mmHg; 95% CI -2.95, 29.32). The number of ventilation-free days and the mean duration of ventilation could not undergo pooled analysis due to a lack of sufficient data.


CONCLUSIONS
Exogenous surfactant may improve oxygenation but has not been shown to improve mortality. Currently, exogenous surfactant cannot be considered an effective adjunctive therapy in acute respiratory distress syndrome.
Department of Medicine University of British Columbia, Vancouver, British Columbia, Canada. Warren.Davidson@calgaryhealthregion.ca
Warren J
WJ
Davidson
Del
D
Dorscheid
Roger
R
Spragg
Michael
M
Schulzer
Edwin
E
Mak
Najib T
NT
Ayas
D000328:Adult; D006801:Humans; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic / Q000401:mortality; D012128:Respiratory Distress Syndrome / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology
D011663:Pulmonary Surfactants