Effect of Aspirin, Hemodilution and Desmopressin on Platelet Dysfunction

• Status: Completed
• Trial end date: 2013-09-01
• Target enrollment: 0
• Participant gender: All

Summary

Study hypothesis: Desmopressin (DDAVP) can improve platelet function under influence of aspirin, hemodilution and mild hypothermia

Mild hypothermia (34-35oC) is known to cause platelet dysfunction. This could lead to increased surgical bleeding and increased transfusion requirement during surgery. Although this hypothermia-induced platelet dysfunction seems to be reversible with warming, this is not always possible or desirable.

Desmopressin (DDAVP) is a drug which has proven efficacy in improving platelet function in uraemic and cirrhosis patients, and in reducing blood loss in selected surgeries. In a recent study, we have found that subcutaneous injection of 1.5 mcg (1/10th the usual dose) is already sufficient to fully reverse the platelet dysfunction seen at 32oC. We have demonstrated in another study that prolongation of the bleeding time in a 20% hemodiluted sample predicts increased postoperative bleeding after total knee replacement.

We have therefore designed this study as a follow up to our last two studies on DDAVP and hypothermia, to investigate whether hemodilution affects hypothermia induced platelet dysfunction and the response to DDAVP. In addition, another common cause of perioperative platelet dysfunction is the intake of COX inhibitors, particularly aspirin by patients. Therefor the effect of aspirin on hypothermia induced platelet dysfunction and the response to DDAVP, will also be investigated.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: The University of Hong Kong
• Treatments: Aspirin; Deamino Arginine Vasopressin

Criteria

Inclusion Criteria:

• 60 adult Chinese subjects aged 18-60 without known platelet disorder, thrombocytopenia, history of taking drugs that may affect platelet function including herbal preparations.

Exclusion Criteria:

1. Any known platelet or coagulation disorder

2. Expected surgical operation or dental treatment within one week of scheduled drug intake.

3. Known peptic ulcer disease

4. Obesity (BMI >=30)

5. Pregnant or lactating women.

6. Known chronic liver or renal disease.

7. Coronary artery, carotid artery or peripheral artery disease

8. Recent history of taking antiplatelet drugs, anticoagulants or herbal preparations.

9. Smoker or alcohol user

10. Mentally incapable of providing informed consent

11. Students or junior staff members who had direct working relationship with the PI