Thrombocytopenia and Adverse Bleeding Events in Neonatal Lumbar Punctures in the Emergency Department.

OBJECTIVE: Lumbar punctures are performed as part of a routine evaluation of neonates with fever in the emergency department. Current recommendations regarding performing a lumbar puncture in the presence of thrombocytopenia exist for children with leukemia and other cancers; however, there are no such recommendations for the general neonatal population. This study assesses the frequency of thrombocytopenia and adverse bleeding events in neonates who undergo a lumbar puncture to determine whether a complete blood count, and specifically the platelet count, should be reviewed before performing the lumbar puncture.

METHODS: This is a retrospective chart review of neonates 30 days or younger presenting to a single freestanding pediatric emergency department who received a lumbar puncture over the course of 11 years. The complete blood count was reviewed for thrombocytopenia, determined to be platelet count of less than 150,000/μL. The chart was reviewed for any documented adverse bleeding events associated with the lumbar puncture.

RESULTS: A total population of 2145 was studied with 56 patients determined to be thrombocytopenic. Seven total bleeding events were identified: 1 in the thrombocytopenic group and 6 in the nonthrombocytopenic group. All bleeding events were deemed to be clinically significant, either resulting in prolonged hospital stay or required further workup and medical intervention. The percentage of clinically adverse bleeding events that were related to the lumbar puncture was 0 (0.0%; 95% confidence interval, 0.0%-6.4%) and 2 (0.1%; 95% confidence interval, 0.0%-0.3%) (P = 1.0) in the thrombocytopenic and nonthrombocytopenic groups, respectively.

CONCLUSIONS: Our results demonstrated a very low risk of bleeding events associated with lumbar punctures in neonates, with no increased risk in the thrombocytopenic group. As such, we conclude that waiting for the results of a complete blood count before performing the lumbar puncture in neonates without a known bleeding disorder is unnecessary.