title: Efficacy of paraspinal anesthetic block in patients with chronic pelvic pain refractory to drug therapy: a randomized clinical trial.
abstract: OBJECTIVE
  To determine whether paraspinal block reduces pain scores compared to placebo in women with chronic pelvic pain refractory to drug therapy.
  
  
  METHODS
  Subjects with chronic pelvic pain due to benign conditions and refractory to drug therapy were invited to participate in a randomized, double blind, superiority trial at a tertiary reference center. Subjects were randomly allocated to receive paraspinal anesthetic block with 1% lidocaine without epinephrine or placebo (control). Lidocaine was injected along the spinal process of the painful segment in the supra- and interspinal ligaments using a 25G X 2" needle. Placebo consisted of introduction of the needle in the same segment without injecting any substance. The main outcome measured was the pain score based on a visual analog scale at T0 (baseline), T1 (within 15 min after the procedure) and T2 (one week after the procedure). Data were statistically analyzed by ANOVA and the 95% confidence interval (95%CI).
  
  
  RESULTS
  Mean age was similar for both groups, i.e., 51.2 (paraspinal anesthetic block) and 51.8 years (control). A blind examiner measured the degree of pain according to the visual analog scale from 0 (no pain) to 10 (worst pain imaginable). Based on the visual analog scale, the mean pain scores of the paraspinal anesthetic block group at T0, T1 and T2 were 5.50 (SD=2.92; 95%CI 3.84-7.15), 2.72 (SD=2.10; 95%CI 1.53-3.90), and 4.36 (SD=2.37; 95%CI 1.89-6.82), respectively. The difference between T0 and T1 was statistically significant, with p=0.03.
  
  
  CONCLUSIONS
  Paraspinal anesthetic block had a small effect on visual analog scale pain score immediately after the injections, but no sustained benefit after one week. Further studies are needed to determine the efficacy of paraspinal anesthetic block with different lidocaine doses for the treatment of visceral pain of other causes.
authors.affiliation: Hospital Nossa Senhora da Conceição, Porto Alegre, RS, Brazil.
authors.forename: Karen Felix
authors.initials: KF
authors.lastname: da Rosa
authors.affiliation: Department of Surgery, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Vinícius Atrib
authors.initials: VA
authors.lastname: Amantéa
authors.affiliation: Department of Surgery, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Antônio Cardoso
authors.initials: AC
authors.lastname: dos Santos
authors.affiliation: Department of Gynecology and Obstetrics, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Ricardo Francalacci
authors.initials: RF
authors.lastname: Savaris
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage*; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D010148:Intractable Pain / Q000628:therapy*; D017699:Pelvic Pain / Q000628:therapy*
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine