Blood conservation with membrane oxygenators and dipyridamole

Ann Thorac Surg. 1987 Jul;44(1):40-7. doi: 10.1016/s0003-4975(10)62354-5.


Cardiopulmonary bypass induces platelet activation and dysfunction, which result in platelet deposition and depletion. Reduced platelet numbers and abnormal platelet function may contribute to postoperative bleeding. A membrane oxygenator may preserve platelets and reduce bleeding more than a bubble oxygenator, and the antiplatelet agent dipyridamole may protect platelets intraoperatively and reduce bleeding postoperatively. A prospective randomized trial was performed in 44 patients undergoing elective coronary artery bypass grafting to assess the effects of the membrane oxygenator and dipyridamole on platelet counts, platelet activation products, and postoperative bleeding. Patients who were randomized to receive a bubble oxygenator and no dipyridamole had the lowest postoperative platelet counts, the greatest blood loss, and the most blood products transfused. Platelet counts were highest and blood loss was least in patients randomized to receive a membrane oxygenator and dipyridamole (p less than .05). A bubble oxygenator with dipyridamole and a membrane oxygenator without dipyridamole resulted in intermediate postoperative platelet counts and blood loss. Arterial thromboxane B2 and platelet factor 4 concentrations were elevated on cardiopulmonary bypass in all groups. Both the membrane oxygenator and dipyridamole were independently effective (by multivariate analysis) in preserving platelets. Optimal blood conservation was achieved with a membrane oxygenator and dipyridamole.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 6-Ketoprostaglandin F1 alpha / blood
  • Aged
  • Blood Platelets / drug effects
  • Blood* / drug effects
  • Clinical Trials as Topic
  • Contraceptives, Oral, Combined
  • Coronary Artery Bypass
  • Dipyridamole / administration & dosage
  • Dipyridamole / pharmacology*
  • Hemoglobins / analysis
  • Hemorrhage / epidemiology
  • Humans
  • Leukocyte Count
  • Middle Aged
  • Oxygenators
  • Oxygenators, Membrane*
  • Platelet Count
  • Platelet Factor 4 / analysis
  • Postoperative Complications / epidemiology
  • Prospective Studies
  • Random Allocation
  • Thromboxane B2 / analysis


  • Contraceptives, Oral, Combined
  • Hemoglobins
  • Platelet Factor 4
  • Thromboxane B2
  • 6-Ketoprostaglandin F1 alpha
  • Dipyridamole