title: Elevated upper body position improves pregnancy-related OSA without impairing sleep quality or sleep architecture early after delivery.
abstract: BACKGROUND
  During pregnancy, upper airway resistance is increased, predisposing vulnerable women to pregnancy-related OSA. Elevation of the upper body increases upper airway cross-sectional area (CSA) and improves severity of OSA in a subgroup of nonpregnant patients (positional-dependent sleep apnea). We tested the hypothesis that elevated position of the upper body improves OSA early after delivery.
  
  
  METHODS
  Following institutional review board approval, we conducted a randomized, crossover study on two postpartum units of Massachusetts General Hospital. Women during the first 48 h after delivery were included. Polysomnography was performed in nonelevated and 45° elevated upper body position. Upper airway CSA was measured by acoustic pharyngometry in nonelevated, 45° elevated, and sitting body position.
  
  
  RESULTS
  Fifty-five patients were enrolled, and measurements of airway CSA obtained. Thirty patients completed polysomnography in both body positions. Elevation of the upper body significantly reduced apnea-hypopnea index (AHI) from 7.7 ± 2.2/h in nonelevated to 4.5 ± 1.4/h in 45° elevated upper body position (P = .031) during sleep. Moderate to severe OSA (AHI > 15/h) was diagnosed in 20% of postpartum patients and successfully treated by elevated body position in one-half of them. Total sleep time and sleep architecture were not affected by upper body elevation. Change from nonelevated to sitting position increased inspiratory upper airway CSA from 1.35 ± 0.1 cm2 to 1.54 ± 0.1 cm2 during wakefulness. Position-dependent increase in CSA and decrease in AHI were correlated (r = 0.42, P = .022).
  
  
  CONCLUSIONS
  Among early postpartum women, 45° upper body elevation increased upper airway CSA and mitigated sleep apnea. Elevated body position might improve respiratory safety in women early after delivery.
  
  
  BACKGROUND
  ClinicalTrials.gov; No.: NCT01719224; URL: www.clinicaltrials.gov.
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Sleep Medicine, Department of Neurology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-University, Bonn, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Zaremba
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Noomi
authors.initials: N
authors.lastname: Mueller
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Heisig
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Christina H
authors.initials: CH
authors.lastname: Shin
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Department of Pediatric Surgery, DRK-Kinderklinik Siegen, Teaching Hospital of Philipps University, Marburg, Germany; Department of Pediatric Urology, DRK-Kinderklinik Siegen, Teaching Hospital of Philipps University, Marburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Jung
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Lisa R
authors.initials: LR
authors.lastname: Leffert
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Bateman
authors.affiliation: Department of Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Lori J
authors.initials: LJ
authors.lastname: Pugsley
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Nagasaka
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Ingrid Moreno
authors.initials: IM
authors.lastname: Duarte
authors.affiliation: Department of Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Ecker
authors.affiliation: Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Department of Anesthesia and Critical Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany. Electronic address: meikermann@partners.org.
authors.forename: Matthias
authors.initials: M
authors.lastname: Eikermann
mesh_terms: D000293:Adolescent; D000328:Adult; D000403:Airway Resistance / Q000502:physiology*; D018592:Cross-Over Studies; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D017286:Polysomnography; D011187:Posture / Q000502:physiology*; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D012138:Respiratory Therapy / Q000379:methods*; D012890:Sleep / Q000502:physiology*; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D018667:Tilt-Table Test; D055815:Young Adult