Question 1: For pediatric lumbar punctures (LPs), does advancement of the LP needle without a stylet (ie, stylet out) increase the odds of a successful LP?
Advancement of the LP needle without a stylet has been reported in the adult medical literature since the 1960s.1 After puncturing through the epidermis and subcutaneous tissue with the stylet in place, does advancement with the stylet out allow for earlier recognition of the subarachnoid space, or would the soft pediatric bony structures more easily facilitate materials occluding the needle?
A 17-month prospective observational study in 2006 by Baxter et al evaluated 594 pediatric LPs in children age 12 months or younger in a tertiary pediatric emergency department.2 Of 594 pediatric LPs, data were collected on 428 (72 percent), of which 377 were performed by residents and included in their analysis.
The authors were interested in resident-performed LPs. LP kits included a form for recording several intraprocedural data elements such as patient age, use of anesthetics, use of paper drapes, experience of the person performing the LP, early stylet removal, and number of attempts. The primary outcome was the ability of the resident to successfully perform an LP. Failure was defined as more than 1,000 red blood cells (RBCs)/mm3, inability of the resident to get cerebrospinal fluid (CSF), or inability to get enough volume for a CSF cell count (ie, adequate volume for a CSF culture but not enough for a cell count).