title: REctus Sheath block for postoperative analgesia in gynecological ONcology Surgery (RESONS): a randomized-controlled trial.
abstract: BACKGROUND
  Opioid-sparing pain management is important for Enhanced Recovery After Surgery. Rectus sheath (RS) blocks are emerging as a promising modality for pain relief following midline laparotomy; however, there are limited prospective clinical trials testing their efficacy. The purpose of this randomized-controlled trial is to assess the morphine-sparing effect of local anesthetic (LA) boluses through RS catheters following elective gynecological oncology surgery.
  
  
  METHODS
  After patients' informed consent, bilateral RS catheters were placed intraoperatively in 74 females (American Society of Anesthesiologists physical status I-II) undergoing elective midline laparotomy under general anesthesia. The patients were randomized to receive 20-mL injections of either LA (0.25% bupivacaine) or normal saline (NS) postoperatively every six hours for 48 hr. Groups were compared for the co-primary outcomes of 24- and 48-hr morphine requirements. The secondary outcomes were numeric rating scale (NRS) scores for pain recorded at rest and with movement.
  
  
  RESULTS
  The mean (SD) morphine consumption was significantly reduced in the LA group compared with the NS group at 24 hr [8.8 (8.3) mg vs 27.3 (10.0) mg, respectively; mean difference, 18.5 mg; 95% confidence interval (CI), 14.3 to 22.8; P < 0.001] and at 48 hr [14.8 (11.0) mg vs 42.4 (16.8) mg, respectively; mean difference, 27.7 mg; 95% CI, 20.9 to 34.3; P < 0.001]. At 48 hr postoperatively, there was also a significant decrease in the median [interquartile range] NRS scores for pain in the LA group compared with the NS group, both at rest (3 [2-3] vs 5 [5-6], respectively; P < 0.001) and with movement (4 [4-5] vs 7 [6-8], respectively; P < 0.001).
  
  
  CONCLUSIONS
  The use of intermittent LA boluses through RS catheters is an effective morphine-sparing pain management strategy for females undergoing midline laparotomy for gynecological cancer surgery. This study was registered with the Clinical Trial Registry of India (CTRI/2013/10/004075).
authors.affiliation: Department of Anesthesia, Critical Care & Pain, Tata Memorial Hospital, Parel, Mumbai, India. sumitrabakshi@yahoo.in.
authors.forename: Sumitra G
authors.initials: SG
authors.lastname: Bakshi
authors.affiliation: Department of Anesthesia, Critical Care & Pain, Tata Memorial Hospital, Parel, Mumbai, India.
authors.forename: Amol
authors.initials: A
authors.lastname: Mapari
authors.affiliation: Department of Gynecological Oncology, Tata Memorial Hospital, Parel, Mumbai, India.
authors.forename: T S
authors.initials: TS
authors.lastname: Shylasree
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D057785:Catheters; D004311:Double-Blind Method; D005260:Female; D013509:Gynecologic Surgical Procedures / Q000379:methods*; D006801:Humans; D007813:Laparotomy; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D017568:Rectus Abdominis; D016896:Treatment Outcome
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine