title: Immediate pain response to interlaminar lumbar epidural steroid administration: response characteristics and effects of anesthetic concentration.
abstract: OBJECTIVE
  Interlaminar LESIs are commonly used to treat LBP or radiculopathy. Most studies focus on the long-term outcomes of LESI. The purpose of this study is to evaluate the immediate effects of fluoroscopically guided LESI on LBP/radiculopathy including low- or high-strength anesthetic response.
  
  
  METHODS
  The procedure notes, post-procedure records, and imaging records dedicated spine nurse assessments, and imaging records were retrospectively evaluated in 392 fluoroscopically guided LESIs performed in 276 patients (nonrandomized, nonblinded; 131 males, 145 females; average age, 56 years) with LBP/radiculopathy using either low- or high-strength anesthetic (80 mg of methylprednisilone mixed with bupivacaine [0.25% or 0.5%]). Post-procedure documentation of the patient's pre- and postprocedure VAS pain-scale level were tabulated.
  
  
  RESULTS
  Single LESI was performed in 199 patients, with multiple LESIs in 77 (193 injections). Low-strength bupivacaine (0.25%) was used in 237 injections, with high-strength (0.5%) in 155. Complete to near-complete immediate pain relief (<20% residual pain) was reported after 197 of 392 (50.3%) injections. No pain relief was reported after 60 (15.4%) injections (>80% residual), with partial relief in the remainder. No statistical difference was noted between low- and high-anesthetic strength or between single- and multiple-injection patients. In multiple-LESI patients, consistent pain relief response was noted in 39 of 77 (50.6%) patients, with improving LESI response in 20.8%, deteriorating LESI response in 19.5%, and variable response in 9.1%.
  
  
  CONCLUSIONS
  An immediate pain-extinction response is identified after LESI, which appears independent of anesthetic strength. This observation may relate to pain origin and/or pain nociceptor afferent pathway in an individual patient and potentially relate to treatment response.
authors: Department of Radiology, Division of Neuroradiology, Presbyterian University Hospital, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213, USA. bartynskiws@upmc.edu
authors: W S
authors: WS
authors: Bartynski
authors: R B
authors: RB
authors: Jennings
authors: W E
authors: WE
authors: Rothfus
authors: V
authors: V
authors: Agarwal
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000779:Anesthetics, Local / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D015994:Incidence; D007268:Injections, Epidural / Q000379:methods / Q000706:statistics & numerical data*; D017116:Low Back Pain / Q000188:drug therapy* / Q000453:epidemiology*; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000187:drug effects; D010414:Pennsylvania / Q000453:epidemiology; D011843:Radiculopathy / Q000188:drug therapy* / Q000453:epidemiology*; D013256:Steroids / Q000008:administration & dosage*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000779:Anesthetics, Local; D013256:Steroids