title: Chronic intermittent hypoxia is independently associated with reduced postoperative opioid consumption in bariatric patients suffering from sleep-disordered breathing.
abstract: BACKGROUND
  Evidence suggests that recurrent nocturnal hypoxemia may affect pain response and/or the sensitivity to opioid analgesia. We tested the hypothesis that nocturnal hypoxemia, quantified by sleep time spent at an arterial saturation (SaO2) < 90% and minimum nocturnal SaO2 on polysomnography, are associated with decreased pain and reduced opioid consumption during the initial 72 postoperative hours in patients having laparoscopic bariatric surgery.
  
  
  METHODS
  With Institutional Review Board approval, we examined the records of all patients who underwent laparoscopic bariatric surgery between 2004 and 2010 and had an available nocturnal polysomnography study. We assessed the relationships between the time-weighted average of pain score and total opioid consumption during the initial 72 postoperative hours, and: (a) the percentage of total sleep time spent at SaO2 < 90%, (b) the minimum nocturnal SaO2, and (c) the number of apnea/hypopnea episodes per hour of sleep. We used multivariable regression models to adjust for both clinical and sleep-related confounders.
  
  
  RESULTS
  Two hundred eighteen patients were included in the analysis. Percentage of total sleep time spent at SaO2 < 90% was inversely associated with total postoperative opioid consumption; a 5-%- absolute increase in the former would relatively decrease median opioid consumption by 16% (98.75% CI: 2% to 28%, P = 0.006). However, the percentage of total sleep time spent at SaO2 < 90% was not associated with pain. The minimum nocturnal SaO2 was associated neither with total postoperative opioid consumption nor with pain. In addition, neither pain nor total opioid consumption was significantly associated with the number of apnea/hypopnea episodes per hour of sleep.
  
  
  CONCLUSIONS
  Preoperative nocturnal intermittent hypoxia may enhance sensitivity to opioids.
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Alparslan
authors.initials: A
authors.lastname: Turan
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Jing
authors.initials: J
authors.lastname: You
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Cameron
authors.initials: C
authors.lastname: Egan
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Alex
authors.initials: A
authors.lastname: Fu
authors.affiliation: Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Ashish
authors.initials: A
authors.lastname: Khanna
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Yashar
authors.initials: Y
authors.lastname: Eshraghi
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Raktim
authors.initials: R
authors.lastname: Ghosh
authors.affiliation: Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Somnath
authors.initials: S
authors.lastname: Bose
authors.affiliation: Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Shahbaz
authors.initials: S
authors.lastname: Qavi
authors.affiliation: Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Lovkesh
authors.initials: L
authors.lastname: Arora
authors.affiliation: Department of Outcomes Research, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
authors.affiliation: Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, California, United States of America; Outcomes Research Consortium, Cleveland, Ohio, United States of America.
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Doufas
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D050110:Bariatric Surgery / Q000009:adverse effects*; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000188:drug therapy / Q000503:physiopathology; D017286:Polysomnography; D012891:Sleep Apnea Syndromes / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology
chemical_list: D000701:Analgesics, Opioid