title: Elevated Extravascular Lung Water Index (ELWI) as a Predictor of Failure of Continuous Positive Airway Pressure Via Helmet (Helmet-CPAP) in Patients With Acute Respiratory Failure After Major Surgery.
abstract: BACKGROUND
  NIV is increasingly used for prevention and treatment of respiratory complications and failure. Some of them are admitted to the PACU with advanced hemodynamic monitors which allow quantification of Extravascular Lung Water (EVLW) by transpulmonary thermodilution technique (TPTD) and Pulmonary Vascular Permeability (PVP) providing information on lung edema.
  
  
  OBJECTIVE
  The objective of this study was to ascertain if EVLW Index and PVP Index may predict failure (intubation) or success (non-intubation) in patients developing acute respiratory failure (ARF) in the postoperative period following major abdominal surgery, where the first line of treatment was non-invasive continuous positive airway pressure via a helmet.
  
  
  METHODS
  Hemodynamic variables, EVLWI and PVPI were monitored with a transpulmonary thermodilution hemodynamic monitor device (PiCCO™) before and after the application of CPAP.
  
  
  RESULTS
  Avoidance of intubation was observed in 66% of patients with Helmet-CPAP. In these patients after the first hour of application of CPAP, PaO2/FiO2 ratio significantly increased (303.33±65.2 vs. 141.6±14.6, P<.01). Before starting Helmet-CPAP values of EVLWI and PVPI were significantly lower in non-intubated patients (EVLWI 8.6±1.08 vs. 11.8±0.99ml/kg IBW, P<.01 and PVPI 1.7±0.56 vs. 3.0±0.88, P<.01). An optimal cut-off value for EVLWI was established at 9.5, and at 2.45 for PVPI (sensitivity of 0.7; specificity of 0.9, P<.01).
  
  
  CONCLUSIONS
  In this type of patient the physiological parameters that predict the failure of Helmet-CPAP with the greatest accuracy were the value of the EVLWI and PVPI before Helmet-CPAP institution and the PaO2/FiO2 ratio and the respiratory rate after one hour of CPAP.
authors.affiliation: Servicio de Anestesiología y Medicina Intensiva, Hospital General Universitario de Ciudad Real, Ciudad Real, España. Electronic address: ardredondo@hotmail.com.
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Redondo Calvo
authors.affiliation: Servicio de Pediatría, Hospital General Universitario de Ciudad Real, Ciudad Real, España.
authors.forename: Natalia
authors.initials: N
authors.lastname: Bejarano Ramirez
authors.affiliation: Servicio de Anestesiología y Medicina Intensiva, Hospital Universitario La Paz, Madrid, España.
authors.forename: Rafael
authors.initials: R
authors.lastname: Uña Orejon
authors.affiliation: Servicio de Anestesiología y Medicina Intensiva, Hospital General Universitario de Ciudad Real, Ciudad Real, España.
authors.forename: Ruben
authors.initials: R
authors.lastname: Villazala Garcia
authors.affiliation: Servicio de Anestesiología y Medicina Intensiva, Hospital General Universitario de Ciudad Real, Ciudad Real, España.
authors.forename: Ana Sofia
authors.initials: AS
authors.lastname: Yuste Peña
authors.affiliation: Servicio de Anestesiología y Medicina Intensiva, Hospital Clínico Universitario de Valencia, Valencia, España.
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Belda
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002199:Capillary Permeability; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation / Q000379:methods*; D003422:Critical Care; D015633:Extravascular Lung Water; D005260:Female; D006260:Head Protective Devices; D006439:Hemodynamics; D006801:Humans; D007442:Intubation, Intratracheal / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood; D011183:Postoperative Complications / Q000628:therapy*; D011652:Pulmonary Circulation; D011654:Pulmonary Edema / Q000175:diagnosis* / Q000209:etiology; D012372:ROC Curve; D012131:Respiratory Insufficiency / Q000628:therapy*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013815:Thermodilution / Q000295:instrumentation*; D017211:Treatment Failure
chemical_list: D010100:Oxygen
keywords: Agua pulmonar extravascular; Continuous positive airway pressure; Extravascular lung water; Hemodynamic monitoring; Insuficiencia respiratoria postoperatoria; Monitorización hemodinámica; Non-invasive ventilation; Postoperative respiratory failure; Presión positiva continua en la vía aérea; Pulmonary vascular permeability index; Ventilación no invasiva; Índice de permeabilidad vascular pulmonar