Regional anesthesia and pain medicine
-
Reg Anesth Pain Med · Jul 2008
The sensitivity of motor response to needle nerve stimulation during ultrasound guided interscalene catheter placement.
Neurostimulation during single shot interscalene block has a significant false negative motor response rate. Compared with tangential needle approaches for single shot block, interscalene catheter (ISC) placement commonly involves Tuohy needles inserted longitudinally to the brachial plexus. This study aimed to determine the sensitivity of neurostimulation during ultrasound-guided ISC needle placement, and the feasibility of an ultrasound-guided ISC needle endpoint. ⋯ This study suggests that the false negative motor response rate for longitudinal ISC needle placement is higher than the false negative response rate associated with tangential needle approach interscalene block. An ultrasound guided ISC needle endpoint is a feasible alternative to a neurostimulation endpoint.
-
Reg Anesth Pain Med · May 2008
Comparative StudySonoanatomy of the lumbar spine in patients with previous unintentional dural punctures during labor epidurals.
Preprocedural lumbar ultrasound is a valuable tool to assess anatomical landmarks and predict the depth of the epidural space. Variations of the ligamentum flavum sonoanatomy are occasionally observed; however, no literature is available as to their incidence or clinical significance. We hypothesize that abnormal sonoanatomy of the lumbar spine detected by ultrasound can be associated with an increase in unintentional dural punctures. This study was undertaken to determine if the sonoanatomy of the lumbar spine of patients who had documented unintentional dural punctures differs from that of patients with a history of uneventful epidural placement for labor analgesia. ⋯ Abnormal sonoanatomy of the ligamentum flavum may represent anatomical variations of this structure, which may be related to an increased incidence of unintentional dural punctures during epidural placements.
-
Reg Anesth Pain Med · May 2008
Contralateral neuropathic pain following a surgical model of unilateral nerve injury in rats.
Damage to peripheral nerves provokes chronic neuropathic pain that lasts beyond the duration of the nerve injury. The presence of pain signs have been reported in areas other than those attributed to the injured nerve, i.e., in contralateral regions. We evaluated the presence, magnitude, and chronology of mechanical and cold allodynia in the contralateral paw of rats undergoing unilateral ligation of the L5 and L6 spinal nerves. ⋯ After L5 and L6 spinal nerve ligation, rats developed mechanical and cold allodynia in the contralateral paw, suggesting extraterritorial development of neuropathic signs. This finding has implications for future study design and therapeutic approaches.