title: A dose-ranging study of the effect of transversus abdominis block on postoperative quality of recovery and analgesia after outpatient laparoscopy.
abstract: BACKGROUND
  Postoperative pain can delay functional recovery after outpatient surgery. Multimodal analgesia can improve pain and possibly improve quality of recovery. In this study, we evaluated the dose-dependent effects of a preoperative transversus abdominis plane (TAP) block on patient recovery using the Quality of Recovery 40 (QoR-40) questionnaire after ambulatory gynecological laparoscopic surgery. Global QoR-40 scores range from 40 to 200, representing very poor to outstanding quality of recovery, respectively.
  
  
  METHODS
  Healthy women undergoing outpatient gynecological laparoscopy were randomly allocated to receive a preoperative TAP block using saline, ropivacaine 0.25%, or ropivacaine 0.5%. Needle placement for the TAP blocks was performed using ultrasound guidance and 15 mL of the study solution was injected bilaterally by a blinded investigator. QoR-40 score and analgesic use were assessed 24 hours postoperatively. The primary outcome was global QoR-40 score at 24 hours after surgery. Data were analyzed using the Kruskal-Wallis test. Post hoc pairwise comparisons were made using the Dunn test with P values and 95% confidence intervals Bonferroni corrected for 6 comparisons.
  
  
  RESULTS
  Seventy-five subjects were enrolled and 70 subjects completed the study. The median (range) for the QoR-40 score after the TAP block was 157 (127-193), 173 (133-195), and 172 (130-196) for the saline group and 0.25% and 0.5% ropivacaine groups, respectively. The median difference (99.2% confidence interval) in QoR-40 score for 0.5% bupivacaine (16 [1-30], P=0.03) and 0.25% bupivacaine (17 [2-31], P=0.01) was more than saline but not significantly different between ropivacaine groups (-1 [-16 to 12], P=1.0). Increased global QoR-40 scores correlated with decreased area under the pain score time curve during postanesthesia recovery room stay (ρ=-0.56, 99.2% upper confidence limit [UCL]=-0.28), 24-hour opioid consumption (ρ=-0.61, 99.2% UCL=-0.34), pain score (0-10 scale) at 24 hours (ρ=-0.53, 99.2% UCL=-0.25), and time to discharge readiness (ρ=-0.65, 99.2% UCL=-0.42). The aforementioned variables were lower in the TAP block groups receiving ropivacaine compared with saline.
  
  
  CONCLUSIONS
  The TAP block is an effective adjunct in a multimodal analgesic strategy for ambulatory laparoscopic procedures. TAP blocks with ropivacaine 0.25% and 0.5% reduced pain, decreased opioid consumption, and provided earlier discharge readiness that was associated with better quality of recovery.
authors.affiliation: Department of Anesthesiology, Northwestern University Feinberg School of Medicine, 251 E. Huron St., Feinberg 5-704, Chicago, IL 60611, USA. g-jr@northwestern.edu
authors.forename: Gildasio S
authors.initials: GS
authors.lastname: De Oliveira
authors.forename: Paul C
authors.initials: PC
authors.lastname: Fitzgerald
authors.forename: R-Jay
authors.initials: RJ
authors.lastname: Marcus
authors.forename: Shireen
authors.initials: S
authors.lastname: Ahmad
authors.forename: Robert J
authors.initials: RJ
authors.lastname: McCarthy
mesh_terms: D000005:Abdomen / Q000000981:diagnostic imaging; D000328:Adult; D000556:Ambulatory Surgical Procedures / Q000379:methods*; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D000762:Anesthesia Recovery Period; D000779:Anesthetics, Local; D004311:Double-Blind Method; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D009020:Morphine / Q000008:administration & dosage / Q000627:therapeutic use; D009407:Nerve Block / Q000009:adverse effects / Q000379:methods*; D010147:Pain Measurement / Q000187:drug effects; D010149:Postoperative Pain / Q000517:prevention & control*; D010880:Piperidines; D011229:Preanesthetic Medication; D000077208:Remifentanil; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D010880:Piperidines; D009020:Morphine; D000077208:Remifentanil