Efficacy of Adjuvant 10% Hypertonic Saline in Transforaminal Epidural Steroid Injection: A Retrospective Analysis.

BACKGROUND: Chronic lower back pain with or without radiculopathy represents an important medical, social, and economic problem. Many treatment modalities and techniques, including surgery and epidural administration of steroids, have been used to manage this pain. Hypertonic saline, which has been used as an adjunct to percutaneous epidural adhesiolysis, can also be injected via a transforaminal approach in expectation of longer-lasting effects. OBJECTIVES: This study aimed to determine the effect of adding hypertonic saline to conventional transforaminal epidural steroid injections (TFEI) to provide pain relief for chronic radiculopathy patients. STUDY DESIGN: A retrospective study. SETTING: Pain clinic of a university hospital. METHODS: Between January 2010 and December 2013, the medical records of 246 patients (94 in the hypertonic group, 153 in the control group) who received transforaminal epidural block were reviewed and analyzed. The hypertonic group received 10% sodium chloride solution added to lidocaine, triamcinolone, and hyaluronidase. Outcomes on pain reduction were measured using a numerical rating scale (NRS) and the responder rate at baseline, one, 3, and 6 months after procedure. RESULTS: The estimated difference in NRS scores from baseline throughout a 6-month follow-up period in the hypertonic group were significantly higher (P = 0.0003). The proportion of substantial responders (41.9% vs. 34.6% at one month, 40.9% vs. 26.8% at 3 months, and 33.3% vs. 14.4% at 6 months, respectively, P = 0.0058) and substantial/moderate responders (71.0% vs. 58.8% at one month, 65.6% vs. 40.4% at 3 months, and 48.4% vs. 20.3% at 6 months, respectively, P < 0.0001) were significantly higher in the hypertonic group. The Oswestry disability index (ODI) was not different between the groups (P = 0.2697). LIMITATIONS: Retrospective design without a control group. CONCLUSIONS: Hypertonic saline provides more superior and longer lasting pain relieving effects when added to TFEIs.Key words: Back pain, epidural injections, epidural steroids, hypertonic saline, lumbar, radiculopathy, transforaminal.

A case report: Clinical application of celiac plexus block in bile duct interventional procedures.

Although percutaneous transhepatic biliary drainage (PTBD) and tract dilatation (TD) are very painful procedures, almost all of those procedures have been conducted under local anesthesia and opioid injection due to the lack of manpower and time. Celiac plexus block (CPB) is an interventional technique used for diagnostic and therapeutic purposes in the treatment of abdominovisceral pain. CPB decreases the side effects of opioid medications and enhances analgesia from medications. We present the case of a patient who underwent PTBD and TD under CPB in order to reduce procedure-related abdominal pain.CPB can be a useful alternative technique for pain management during and after biliary interventional procedures, although CPB-induced complications must always be kept in mind.

The preventive effect of resiniferatoxin on the development of cold hypersensitivity induced by spinal nerve ligation: involvement of TRPM8.

BACKGROUND: Resiniferatoxin (RTX) is a potent analog of capsaicin and activates transient receptor potential (TRP) vanilloid type (TRPV) 1. In the current study, we investigated the preventive effect of perineural RTX on the development of cold hypersensitivity induced by spinal nerve ligation (SNL) in rats. Furthermore, we examined the association between the expression level of TRPV1, TRP ankyrin type (TRPA) 1 and TRP melastatin type (TRPM) 8 in the dorsal root ganglion (DRG) and cold hypersensitivity after SNL. RESULTS: RTX pretreatment prevented the development of SNL-induced hypersensitivity to mechanical, thermal, and cold stimuli. Western blot analysis 4 weeks after RTX pretreatment showed that RTX pretreatment decreased the protein expression level of SNL-induced TRPM8, but not TRPV1 or TRPA1, in the DRG of SNL rats. Immunofluorescent analysis revealed that up-regulated TRPM8-stained neurons after SNL co-localized with neurofilament 200-positive neurons located in the DRG. CONCLUSIONS: Pretreatment with perineural RTX significantly inhibits SNL-induced mechanical, thermal, and cold hypersensitivity. The antinociceptive effect of perineural RTX, especially on cold hypersensitivity, may be related to the suppression of TRPM8 expression in DRG.

Effects of nefopam on streptozotocin-induced diabetic neuropathic pain in rats.

BACKGROUND: Nefopam is a centrally acting non-opioid analgesic agent. Its analgesic properties may be related to the inhibitions of monoamine reuptake and the N-methyl-D-aspartate (NMDA) receptor. The antinociceptive effect of nefopam has been shown in animal models of acute and chronic pain and in humans. However, the effect of nefopam on diabetic neuropathic pain is unclear. Therefore, we investigated the preventive effect of nefopam on diabetic neuropathic pain induced by streptozotocin (STZ) in rats. METHODS: Pretreatment with nefopam (30 mg/kg) was performed intraperitoneally 30 min prior to an intraperitoneal injection of STZ (60 mg/kg). Mechanical and cold allodynia were tested before, and 1 to 4 weeks after drug administration. Thermal hyperalgesia was also investigated. In addition, the transient receptor potential ankyrin 1 (TRPA1) and TRP melastatin 8 (TRPM8) expression levels in the dorsal root ganglion (DRG) were evaluated. RESULTS: Pretreatment with nefopam significantly inhibited STZ-induced mechanical and cold allodynia, but not thermal hyperalgesia. The STZ injection increased TRPM8, but not TRPA1, expression levels in DRG neurons. Pretreatment with nefopam decreased STZ-induced TRPM8 expression levels in the DRG. CONCLUSIONS: These results demonstrate that a nefopam pretreatment has strong antiallodynic effects on STZ-induced diabetic rats, which may be associated with TRPM8 located in the DRG.