Inhaled prostacyclin and platelet function after cardiac surgery and cardiopulmonary bypass.
OBJECTIVE
To study the effects of 6 h inhalation of aerosolized prostacyclin (PGI2) on platelet function.


METHODS
In a prospective, double-blind, randomized study, 28 patients scheduled for elective cardiac surgery requiring cardiopulmonary bypass (CPB), received either 0.9% sodium chloride (n = 8), PGI2 5 microg x ml(-1) (n = 10) or PGI2 10 microg x ml(-1) (n = 10) as an aerosol for 6 h postoperatively.


METHODS
Cardiothoracic intensive care unit at a university hospital.


METHODS
All patients were studied immediately after surgery during mechanical ventilation and sedation. The PGI2 solutions or saline were administered with a jet nebulizer.


RESULTS
Bleeding time and chest tube drainage were measured. Blood samples for platelet aggregation, thrombelastography (TEG) and analysis of coagulation parameters and the stable prostacyclin metabolite 6-keto-PGF1alpha were obtained immediately before inhalation and after 2, 4 and 6 h of inhalation. After 6 h of PGI2 inhalation, regardless of administered dose, there was a lower rate of platelet aggregation and a lower maximal increase in light transmission in response to adenosine diphosphate (ADP) than in the control group. The TEG variable reaction time (R) was prolonged after 4 and 6 h of inhalation in the PGI2 group receiving 10 microg x ml(-1). There were no differences between groups with respect to bleeding time and chest tube drainage or any of the other variables examined.


CONCLUSIONS
Inhalation of PGI2 for 6 h in patients after cardiac surgery is associated with impaired platelet aggregation detected by in vitro techniques, with no in vivo signs of platelet dysfunction.
Haraldsson
A
A
Department of Cardiothoracic Anesthesia and Intensive Care, Sahlgrenska University Hospital, Göteborg, Sweden.
Kieler-Jensen
N
N
Wadenvik
H
H
Ricksten
S E
SE
D000280:Administration, Inhalation; D000368:Aged; D000704:Analysis of Variance; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D011464:Epoprostenol / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D009330:Nebulizers and Vaporizers; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000494:pharmacology; D010976:Platelet Count / Q000187:drug effects; D011182:Postoperative Care; D011446:Prospective Studies
D010975:Platelet Aggregation Inhibitors; D011464:Epoprostenol