Pulmonary vascular dysfunction is associated with poor outcomes in patients with acute lung injury.
BACKGROUND
Despite the recognition that acute lung injury (ALI) can elevate pulmonary artery (PA) pressure and right ventricular afterload, the impact of pulmonary vascular dysfunction on outcomes of these patients is not well defined.


OBJECTIVE
To investigate the impact of pulmonary vascular dysfunction in patients with acute lung injury.


METHODS
Secondary analysis of the Fluid and Catheter Treatment Trial. A total of 501 patients who received a PA catheter were evaluated for associations between increases in transpulmonary gradient (TPG) (PA mean pressure - PA occlusion pressure) or pulmonary vascular resistance index (PVRi) and 60-day mortality, ventilator-, intensive care unit (ICU)-, and cardiovascular-free days (days with mean arterial pressure ≥ 60 mm Hg off vasopressor support).


RESULTS
We were able to measure the TPG in 475 (95%) and the PVRi in 470 (92%) patients. Patients with an elevated baseline TPG had an increased 60-day mortality (30 versus 19%; P = 0.02), and lower numbers of median ventilator- [25-75% quartiles] (15 [0-22] versus 19 [7-24]; P = 0.005), ICU- (14 [0-21] versus 18 [5-22]; P = 0.005), and cardiovascular-free days (23 [12-27] versus 25 [18-27]; P = 0.03). The median PVRi (305 [204-431] dyne s/cm⁵/m²) was elevated early in the course of ALI. PVRi was statistically higher in patients who died (326 [209-518] versus 299 [199-416]; P = 0.01). In individual multivariate models, TPG and PVRi remained independent risk factors for 60-day mortality and decrease in the number of ventilator-, ICU-, and cardiovascular-free days.


CONCLUSIONS
Pulmonary vascular dysfunction is common in ALI, and is independently associated with poor outcomes. Future trials targeting pulmonary vascular dysfunction may be indicated.
Bull
Todd M
TM
University of Colorado Denver, Division of Pulmonary Sciences and Critical Care Medicine, 12700 East 19th Ave., Aurora, CO 80045, USA. todd.bull@ucdenver.edu
Clark
Brendan
B
McFann
Kim
K
Moss
Marc
M
D055371:Acute Lung Injury / Q000453:epidemiology / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D000328:Adult; D000368:Aged; D015897:Comorbidity; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000453:epidemiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011651:Pulmonary Artery / Q000503:physiopathology*; D012128:Respiratory Distress Syndrome / Q000453:epidemiology / Q000503:physiopathology* / Q000628:therapy; D016019:Survival Analysis; D014655:Vascular Resistance