title: Fluid management in critically ill patients: the role of extravascular lung water, abdominal hypertension, capillary leak, and fluid balance.
abstract: BACKGROUND
  Capillary leak in critically ill patients leads to interstitial edema. Fluid overload is independently associated with poor prognosis. Bedside measurement of intra-abdominal pressure (IAP), extravascular lung water index (EVLWI), fluid balance, and capillary leak index (CLI) may provide a valuable prognostic tool in mechanically ventilated patients.
  
  
  METHODS
  We performed an observational study of 123 mechanically ventilated patients with extended hemodynamic monitoring, analyzing process-of-care variables for the first week of ICU admission. The primary outcome parameter was 28-day mortality. ΔmaxEVLWI indicated the maximum difference between EVLWI measurements during ICU stay. Patients with a ΔmaxEVLWI <-2 mL/kg were called 'responders'. CLI was defined as C-reactive protein (milligrams per deciliter) over albumin (grams per liter) ratio and conservative late fluid management (CLFM) as even-to-negative fluid balance on at least two consecutive days.
  
  
  RESULTS
  CLI had a biphasic course. ΔmaxEVLWI was lower if CLFM was achieved and in survivors (-2.4 ± 4.8 vs 1.0 ± 5.5 mL/kg, p = 0.001; -3.3 ± 3.8 vs 2.5 ± 5.3 mL/kg, p = 0.001, respectively). No CLFM achievement was associated with increased CLI and IAPmean on day 3 and higher risk to be nonresponder (odds ratio (OR) 2.76, p = 0.046; OR 1.28, p = 0.011; OR 5.52, p = 0.001, respectively). Responders had more ventilator-free days during the first week (2.5 ± 2.3 vs 1.5 ± 2.3, p = 0.023). Not achieving CLFM and being nonresponder were strong independent predictors of mortality (OR 9.34, p = 0.001 and OR 7.14, p = 0.001, respectively).
  
  
  CONCLUSIONS
  There seems to be an important correlation between CLI, EVLWI kinetics, IAP, and fluid balance in mechanically ventilated patients, associated with organ dysfunction and poor prognosis. In this context, we introduce the global increased permeability syndrome.
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Colin
authors.initials: C
authors.lastname: Cordemans
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Inneke
authors.initials: I
authors.lastname: De Laet
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Niels
authors.initials: N
authors.lastname: Van Regenmortel
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Karen
authors.initials: K
authors.lastname: Schoonheydt
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Hilde
authors.initials: H
authors.lastname: Dits
authors.affiliation: II. Medizinische Klinik, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Huber
authors.affiliation: Department of Intensive Care, Ziekenhuis Netwerk Antwerpen, Campus ZNA Stuivenberg, Lange Beeldekensstraat 267, 2060 Antwerpen 6, Belgium.
authors.forename: Manu Lng
authors.initials: ML
authors.lastname: Malbrain