Epidural Injection of Lidocaine Reduces the Response to Dural Puncture Accompanying Spinal Needle Insertion When Performing Combined Spinal-Epidural Anesthesia

Abstract

During placement of needles for combined spinal-epidural anesthesia (CSEA), patients may experience pain, pressure, paresthesia, or discomfort during skin and deeper injection of local anesthetic, needle impingement on periosteum, dural puncture by the spinal needle, and insertion of the epidural catheter. We investigated the incidence of perception of and spontaneous verbal and motor responses to insertion of a spinal needle through the dura mater and pia mater and the effect of injecting lidocaine into the epidural space through the epidural needle before inserting the spinal needle through the meninges. Forty-three patients presenting for elective cesarean delivery under CSEA were studied. After localization of the epidural space using loss of resistance to air using a 17-gauge Tuohy needle, either 3 mL preservative free normal saline or 3 mL lidocaine 2% plus epinephrine 1:200,000 was injected through the Tuohy needle. "Needle through needle" dural puncture was performed 1 min later using a 27-gauge Whitacre pencil-point needle. At the moment of dural puncture, 2 (9%) parturients given lidocaine and 17 (81%) parturients given saline (P < 0.005) responded to dural puncture by spontaneously moving (33%), spontaneously vocalizing (62%), or, in response to direct questioning, by acknowledging (76%) having perceived sensation during thecal penetration. This study reveals that dural puncture by a Whitacre 27-gauge pencil-point needle inserted through a Tuohy epidural needle sited using loss of resistance to air causes involuntary movement, spontaneous vocalization, or is perceived by the majority of patients presenting for cesarean delivery under CSEA and that lidocaine injected into the epidural space before dural puncture largely eliminates these responses and sensations.