title: Positive end-expiratory pressure to increase internal jugular vein size is poorly tolerated in obese anesthetized adults.
abstract: BACKGROUND
  Central venous cannulation is technically challenging in obese patients. We hypothesized that positive end-expiratory pressure (PEEP) increases the size of the internal jugular vein (IJV) in obese adults.
  
  
  METHODS
  The circumference and cross-sectional area of the IJV were measured in obese patients under general anesthesia at PEEP 0, 5, and 10 cm H2O. Results are reported as means ± SE.
  
  
  RESULTS
  PEEP at 10 cm H2O was tolerated by 18 of 24 obese patients. Each 5 cm H2O of PEEP increased the cross-sectional area by 0.16 ± 0.02 cm (P < 0.0001) and the circumference by 0.23 ± 0.03 cm (P < 0.0001).
  
  
  CONCLUSIONS
  PEEP modestly increases the size of the IJV in obese adults but was poorly tolerated because of hypotension.
authors.affiliation: From the Department of Anesthesiology, Pain, and Perioperative Medicine, Stanford University Medical Center, Stanford, California. Laura A. Downey, MD, is currently affiliated with the Department of Anesthesia, Boston Childrens Hospital Boston, Boston, Massachusetts. Kevin P. Blaine, MD, MPH, is currently affiliated with the Critical Care Medicine Department of the National Institutes of Health Clinical Center, Bethesda, Maryland.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Downey
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Blaine
authors.forename: Jan
authors.initials: J
authors.lastname: Sliwa
authors.forename: Alex
authors.initials: A
authors.lastname: Macario
authors.forename: John
authors.initials: J
authors.lastname: Brock-Utne
mesh_terms: D000328:Adult; D000368:Aged; D019412:Anatomy, Cross-Sectional; D000758:Anesthesia; D002405:Catheterization, Central Venous; D005260:Female; D006801:Humans; D007601:Jugular Veins / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D011175:Positive-Pressure Respiration / Q000009:adverse effects*; D013514:Surgical Procedures, Operative