Failure of vasoldilator infusion to alter pulmonary diffusing capacity in systemic sclerosis.
OBJECTIVE
Patients with systemic sclerosis (SSc) do not exhibit a normal increase in the diffusing capacity for carbon monoxide (DLCO) on assuming the supine position. We sought to determine whether a potent prostacyclin derivative and vasodilator, iloprost, would reverse this defect.


METHODS
Fourteen patients with SSc were enrolled in a randomized, double-blind, placebo-controlled study of iloprost. Patients were tested before and during 3 days of iloprost or placebo infusion with both upright and supine pulmonary function studies.


RESULTS
The results of baseline pulmonary function studies including DLCO were not significantly altered by iloprost. Furthermore, iloprost did not alter the abnormal postural DLCO response.


CONCLUSIONS
These results suggest that the pulmonary vascular defects seen in this group of patients are not a consequence of reversible pulmonary vasospasm.
Thurm
C A
CA
Department of Medicine, Johns Hopkins University School of Medicine, Francis Scott Key Medical Center, Baltimore, Maryland.
Wigley
F M
FM
Dole
W P
WP
Wise
R A
RA
D000328:Adult; D000368:Aged; D002248:Carbon Monoxide; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D016285:Iloprost / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011653:Pulmonary Diffusing Capacity / Q000187:drug effects*; D012129:Respiratory Function Tests; D012595:Scleroderma, Systemic / Q000150:complications*; D013484:Supination
D002248:Carbon Monoxide; D016285:Iloprost