Platelet function after off pump coronary surgery

Little is known about the impact of off pump coronary artery bypass (OPCAB) on platelet function. Although improved platelet function may decrease bleeding and reduce cerebral and pulmonary damage, there is a concern that changes in platelet function may also accentuate bypass graft occlusion or other thrombotic processes. In this pilot study we used a point-of-care test--Hemostatus (Medtronic, Minneapolis, MN, USA)--to assess changes in platelet function after OPCAB.

We analyzed data from 11 adult patients undergoing CAB surgery whose platelet function was assessed before and after OPCAB. A Hemostatus test was conducted prior to heparin administration and after protamine reversal.

There was a significant improvement in platelet function as measured in both channels 5 and 6 of the Hemostatus test. Blood loss was 598 +/- 244 mL in the first 24 hours. One patient received blood products.

This pilot study suggests that platelet function is not diminished but instead is improved after OPCAB. This improvement may be due to the release of newer, larger platelets from the bone marrow into the circulation. This finding has important implications for the use of antiplatelet agents perioperatively. Furthermore, more detailed studies in this field are needed.