Retrospective analysis of predisposing factors for difficult lumbar punctures requiring image guidance in pediatric oncology patients.

Success rates of lumbar punctures (LPs) in children are reportedly as low as 50%. In addition to procedural complications and failure, difficult LPs are a risk factor for traumatic LPs (TLPs), which can potentially affect diagnostic utility and alter treatment plans for pediatric oncology patients. To identify the intrinsic factors associated with technically difficult LPs in the pediatric oncology population, we performed a retrospective review of patients who required diagnostic imaging modalities for LP procedures at a single pediatric oncology institution between September 2008 and November 2018. We evaluated data from 64 LPs performed in 33 patients who were referred for image-guided LPs after undergoing technically difficult LPs that were unsuccessful using anatomic landmarks. In these cases, 96.9% of patients had at least one of the following intrinsic factors: body mass index (BMI) ≥ 25, anatomic spinal abnormalities, history of ≥ 5 previous LPs, age < 12 months, and history of back surgery. Elevated BMI was the most common factor associated with difficult LP (81.8%), followed by spinal abnormalities (51.5%), and history of ≥ 5 previous LPs (33.3%). Age < 12 months and history of back surgery were also associated with difficult LPs, but at a lower frequency. On the basis of these findings, we propose clinical recommendations for preprocedural identification of patients at risk of difficult LPs to reduce complications, including TLP, failure, and exposure to general anesthesia.