title: Scheduled intravenous acetaminophen reduces postoperative narcotic analgesic demand and requirement after laparoscopic Roux-en-Y gastric bypass.
abstract: BACKGROUND
  Intravenous (i.v.) acetaminophen has the potential to reduce postoperative narcotic analgesic requirement but this has not been reported in bariatric surgery. As lower dosages could reduce undesirable narcotic side effects, we investigated the opioid-sparing effect of concomitant i.v. acetaminophen in bariatric surgery.
  
  
  METHODS
  We performed a retrospective review of our electronic medical records of laparoscopic Roux-en-Y gastric bypasses (LRYGB) performed for severe obesity between 2011 and 2013. We identified 183 patients that received scheduled i.v. acetaminophen in addition to morphine sulfate (MSO4) patient-controlled analgesia (PCA). A cohort of 229 patients from the preceding 2 years who were treated with MSO4 PCA but not acetaminophen was used as a historical control. Patient demographic characteristics and narcotic use data were extracted from electronic medical records. Student's t test or linear regression was used as appropriate (P< .05).
  
  
  RESULTS
  During the first 24-hour postoperative period after LRYGB, narcotic analgesic demand (total PCA demand including nondelivery of narcotic due to lock-out) was reduced by 25% with the concomitant use of i.v. acetaminophen (40.5 versus 30.9 average pushes; P<.05). During the same period, narcotic analgesic dosage requirement was cut down by 20% in the study group (average of 29.9 versus 24.1 mg of MSO4; P<.05). Linear regression analysis confirmed that these changes were independent of age, gender, and body mass index distribution, or type 2 diabetes mellitus.
  
  
  CONCLUSIONS
  Scheduled i.v. acetaminophen reduces the demand for and the requirement of narcotic analgesia after LRYGB. We provide new evidence in support of the routine use of multimodal analgesia that includes scheduled i.v. acetaminophen in the initial 24-hour period after bariatric surgery.
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
authors.forename: Shireesh
authors.initials: S
authors.lastname: Saurabh
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
authors.forename: Jessica K
authors.initials: JK
authors.lastname: Smith
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
authors.forename: Mark
authors.initials: M
authors.lastname: Pedersen
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
authors.forename: Paul
authors.initials: P
authors.lastname: Jose
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
authors.forename: Peter
authors.initials: P
authors.lastname: Nau
authors.affiliation: Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa. Electronic address: isaac-samuel@uiowa.edu.
authors.forename: Isaac
authors.initials: I
authors.lastname: Samuel
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage*; D061605:Administration, Intravenous; D000293:Adolescent; D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage*; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage*; D009294:Narcotics / Q000008:administration & dosage*; D009767:Obesity, Morbid / Q000601:surgery; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D018712:Analgesics, Non-Narcotic; D009294:Narcotics; D000082:Acetaminophen; D009020:Morphine
keywords: Acetaminophen; Gastric bypass; Morbid obesity; Morphine sulfate; Narcotic analgesia; Patient controlled analgesia; Postoperative analgesia