Safe Use of Low-Molecular-weight Heparin in Pediatric Acute Lymphoblastic Leukemia and Lymphoma Around Lumbar Punctures.

Children with acute lymphoblastic leukemia or lymphoma (ALL) undergo multiple lumbar punctures (LPs) and frequently require low-molecular-weight heparin (LMWH) for thromboembolic complications. We evaluated if withholding LMWH 24 hours before and after LPs prevented bleeding complications. Children (n=133) with ALL from who were: (1) treated at St. Jude Children's Research Hospital, (2) received LMWH (2×/day of ~1 mg/kg) between January 2004 until December 2012, and (3) underwent a LP were analyzed. Spinal hematoma was defined as a clinical suspicion leading to diagnostic imaging. Traumatic LP was defined as ≥10 red blood cells per microliter of cerebrospinal fluid. In 1708 LPs, no hematomas occurred. For each child treated with LMWH, the probability of experiencing a spinal hematoma during the entire ALL treatment course was 0% (95% confidence interval [CI], 0.0%-2.7%), and in each LP, assuming no intrapatient correlation, the probability of spinal hematoma was 0% (95% CI, 0.0%-0.2%). Traumatic LPs were more common when performed when children were not receiving LMWH therapy (odds ratio [OR], 1.5; 95% CI, 1.1-2.2) which may be explained by clinician optimization of known risk factors for traumatic cerebrospinal fluid before the procedures. Withholding LMWH for 24 hours before and after LPs in children being treated for ALL is safe.