When the Introducer Becomes the Limiting Factor: A Technical Note on a Simple Modification to Facilitate Spinal Anesthesia With Pencil-Point Needles in Morbidly Obese Patients

Abstract

Morbid obesity is associated with increased skin-to-dura distance, which may complicate spinal anesthesia using standard-length pencil-point spinal needles. We describe a simple technical modification developed during spinal anesthesia in a parturient with a body mass index of 40 kg/m2, in whom a 27-gauge, 90-mm Whitacre-type spinal needle with the manufacturer-provided introducer was considered insufficient to reach the subarachnoid space. Comparison of the standard introducer with the hub of a conventional 10-mL syringe demonstrated a reduction of approximately 9 mm in external projection beyond the skin surface. The syringe hub was subsequently used as an alternative introducer, effectively increasing the usable length of the spinal needle without altering the needle itself or requiring additional equipment. Awareness of introducer-related reductions in effective working length may help clinicians avoid unnecessary procedure failure or escalation to more invasive alternatives when longer spinal needles are unavailable or impractical.