Low Platelet Counts after Liver Transplantation Predict Early Post-Transplant Survival: The "60-5 Criterion"

Background: Platelets play a critical role in liver injury and regeneration. Thrombocytopenia is associated with increase postoperative complications after partial hepatectomy, but it is unknown whether platelet counts may also predict outcome after transplantation, a procedure often performed in thrombocytopenic patients. Therefore, the aim of this study was to evaluate whether platelet counts are indicators of short- and long-term outcomes after liver transplantation. Methods: Between January 2003 and December 2011, 257 consecutive liver transplantation recipients from our prospective database were analyzed. Pre- and daily postoperative platelet counts were recorded until postoperative day (POD) 7. Uni- and multivariate analyses were performed to assess whether low peri-operative platelet counts are risk factor of postoperative complications, graft and patient survivals. Results: The median pre-transplantation platelet counts was 88 (IQR: 58-127)x10(9) /L. The lowest platelet counts occurred at POD3 with a median of 56 (IQR: 41-86)x10(9) /L. Patients with low platelet counts at POD5 had higher rates of severe complications (grade IIIb-IV) (39% vs. 29%, OR, 1.09 (1.1-3.3), p<0.02) and of 90-day mortality (16% vs. 8%, OR, 2.25 (1.0-5.0), p=0.05). On multivariate analysis, POD5 platelet counts <60x10(9) /L were identified as an independent risk factor of grade IIIb-IV complications (OR, 1.96 (1- 3.5), p=0.01)), graft survival (HR, 2.0 (1.1-3.6), p=0.03)) and patient survival (HR, 2.2 (1.1-4.6), p=0.03)). The graft and patient survival predictive value of platelet counts was lost in patients who survived 90 days. Conclusion: After liver transplantation, platelet counts