title: The passive leg-raising maneuver cannot accurately predict fluid responsiveness in patients with intra-abdominal hypertension.
abstract: OBJECTIVE
  The passive leg-raising maneuver is a reversible fluid-loading procedure used to predict fluid responsiveness in mechanically ventilated patients. The aim of the present study was to determine whether intra-abdominal hypertension (which impairs venous return) reduces the ability of passive leg raising to detect fluid responsiveness in critically ill ventilated patients.
  
  
  METHODS
  A prospective study.
  
  
  METHODS
  The medical and surgical intensive care unit of a university medical center.
  
  
  METHODS
  Forty-one mechanically ventilated patients with a pulse pressure variation of >12%.
  
  
  METHODS
  Stroke volume was continuously monitored by esophageal Doppler. Intra-abdominal pressure was measured via bladder pressure. After a passive leg-raising maneuver and a return to baseline, fluid loading with 500 mL of saline was performed. Hemodynamic parameters were recorded at each step. Nonresponders to volume loading were not analyzed (10 patients). Thirty-one patients were classified into two groups according to their response to passive leg raising: responders to passive leg raising (at least a 12% increase in stroke volume) and nonresponders to passive leg raising.
  
  
  RESULTS
  Sixteen patients (52%) were responders to passive leg raising, and 15 (48%) were nonresponders to passive leg raising (i.e., false negatives). At baseline, the median intra-abdominal pressure was significantly higher in the nonresponders to passive leg raising than in the responders to passive leg raising (20 [6.5] vs. 11.5 [5.5], respectively; p < .0001). The area under the receiver-operating characteristic curve was 0.969 +/- 0.033. An intra-abdominal pressure cutoff value of 16 mm Hg discriminated between responders to passive leg raising and nonresponders to passive leg raising with a sensitivity of 100% (confidence interval, 78-100) and a specificity of 87.5% (confidence interval, 61.6-98.1). An intra-abdominal pressure of > or =16 mm Hg was the only independent predictor of nonresponse to passive leg raising in a multivariate analysis (odds ratio, 2.6 [confidence interval, 1.1-6.6]; p = .04).
  
  
  CONCLUSIONS
  An intra-abdominal pressure of > or =16 mm Hg seems to be responsible for false negatives to passive leg raising. Hence, the intra-abdominal pressure should be measured in critically ill ventilated patients, especially before performing passive leg raising.
authors.affiliation: Medical and Surgical Intensive Care Unit, Department of Anesthesia and Intensive Care, Amiens University Medical Center, Amiens, France. mahjoub.yazine@chu-amiens.fr
authors.forename: Yazine
authors.initials: Y
authors.lastname: Mahjoub
authors.forename: Jérémie
authors.initials: J
authors.lastname: Touzeau
authors.forename: Norair
authors.initials: N
authors.lastname: Airapetian
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Lorne
authors.forename: Mustapha
authors.initials: M
authors.lastname: Hijazi
authors.forename: Elie
authors.initials: E
authors.lastname: Zogheib
authors.forename: François
authors.initials: F
authors.lastname: Tinturier
authors.forename: Michel
authors.initials: M
authors.lastname: Slama
authors.forename: Hervé
authors.initials: H
authors.lastname: Dupont
mesh_terms: D000005:Abdomen; D003161:Compartment Syndromes / Q000503:physiopathology*; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D006973:Hypertension / Q000150:complications; D007866:Leg / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011312:Pressure; D011446:Prospective Studies; D012121:Respiration, Artificial; D016896:Treatment Outcome