Incidence and pattern of thrombocytopenia in cardiac surgery patients

Objective: To observe the incidence and pattern of thrombocytopenia in cardiac surgery patients. Methods: This prospective, cohort study was conducted at the Aga Khan University Hospital, Karachi, from November 2014 to April 2015, and comprised adult cardiac patients. Patients with platelet count less than 150,000 x 10⁹/L, history of malignancy, immune thrombocytopenic purpura and on chemo or radiotherapy were excluded. All information including demographics, platelet count, heparin doses, total cardiopulmonary bypass time, cross-clamp time, blood products transfused, any thromboembolic complication and the presence of infection were recorded on a pre-designed proforma. SPSS 19 was used for data analysis. Results: Of the 177 patients, 130(73.4%) were males and 47(26.6%) were females. The overall mean age was 59.21±10.99 years. Thrombocytopenia was observed in 167(94.4%) patients. Of them, platelet count dropped below 50% in 71(42.5%) patients, 30-50% in 68(40.7%) patients and 20-30% in 28(16.8%) from the baseline value. Regarding pattern of thrombocytopenia, maximum drop in platelet count was noticed on 2nd and 3rd day of surgery. Furthermore, 9(5.3%) patients developed severe thrombocytopenia (<50,000 x 10⁹/L). Conclusion: The incidence of thrombocytopenia and its severity after cardiac surgery was very high in our study population when compared with western population.