Severe Thrombocytopenia in the NICU

OBJECTIVE: Severe thrombocytopenia (platelets <= 50 000/mu L) in a NICU patient can have significant consequences; however, previous reports have not focused exclusively on NICU patients with counts this low. METHODS: We identified all patients with severe thrombocytopenia who were cared for in the Intermountain Healthcare level III NICUs from 2003-2007. RESULTS: Among 11 281 NICU admissions, severe thrombocytopenia was identified in 273 (2.4%). Just over 30% of these presented in the first three days of life. Half presented by day 10, 75% by day 27, and 95% by day 100. The prevalence was inversely related to birth weight. Cutaneous bleeding was more common in patients with platelet counts of <20 000/mu L; however, no statistically significant correlation was found between platelet counts and pulmonary, gastrointestinal, or intraventricular bleeding. The most common explanations for severe thrombocytopenia were acquired varieties of consumptive thrombocytopenia. Platelet transfusions (median 5, range 0-76) were administered to 86% of the patients. No deaths were ascribed to exsanguinations. The mortality rate did not correlate with the lowest platelet count but was proportionate to the number of platelet transfusions. CONCLUSION: The prevalence of severe thrombocytopenia in the NICU is inversely proportional to birth weight and most cases are acquired consumptive thrombocytopenias. We speculate that very low platelet counts are a causal factor in cutaneous bleeding, but pulmonary, gastrointestinal, and intraventricular bleeding are less influenced by the platelet count and occur primarily from causes other than severe thrombocytopenia. The lowest platelet count does not predict the mortality rate but the number of platelet transfusions received does. Pediatrics 2009; 124: e1095-e1100