title: Echocardiographic diagnosis of pulmonary artery occlusion pressure elevation during weaning from mechanical ventilation.
abstract: OBJECTIVE
  Weaning-induced pulmonary edema is a cause of weaning failure in high-risk patients. The diagnosis may require pulmonary artery catheterization to demonstrate increased pulmonary artery occlusion pressure (PAOP) during weaning. Transthoracic echocardiography can estimate left ventricular filling pressures using early (E) and late (A) peak diastolic velocities measured with Doppler transmitral flow, and tissue Doppler imaging of mitral annulus velocities including early (Ea) peak diastolic velocity. We tested the hypothesis that E/A and E/Ea could be used to detect weaning-induced PAOP elevation defined by a PAOP > or =18 mm Hg during a spontaneous breathing trial (SBT).
  
  
  RESULTS
  We included 39 patients who previously failed two consecutive SBTs. A third SBT was performed over a maximum 1-hour period using a T-piece. The PAOP, E/A, and E/Ea were measured before and during this SBT. Receiver operating characteristic curves were constructed to determine the optimal sensitivity and specificity values of E/A and E/Ea obtained at the end of the SBT for predicting a weaning-induced PAOP elevation. Weaning-induced PAOP elevation occurred in 17 patients. A value of E/A >0.95 at the end of the SBT predicted weaning-induced PAOP elevation with a sensitivity of 88% and a specificity of 68%. A value of E/Ea >8.5 at the end of the SBT predicted weaning-induced PAOP elevation with a sensitivity of 94% and a specificity of 73%. The combination of E/A >0.95 and E/Ea >8.5 predicted a weaning-induced PAOP elevation with a sensitivity of 82% and a specificity of 91%.
  
  
  CONCLUSIONS
  At the end of an SBT, the combination of E/A >0.95 and E/Ea >8.5 measured with transthoracic echocardiography allowed an accurate noninvasive detection of weaning-induced PAOP elevation.
authors.affiliation: Service de réanimation médicale, Centre Hospitalo-Universitaire de Bicêtre, Assistance Publique-Hôpitaux de Paris, Université Paris Sud, Le Kremlin-Bicêtre, France.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Lamia
authors.forename: Julien
authors.initials: J
authors.lastname: Maizel
authors.forename: Ana
authors.initials: A
authors.lastname: Ochagavia
authors.forename: Denis
authors.initials: D
authors.lastname: Chemla
authors.forename: David
authors.initials: D
authors.lastname: Osman
authors.forename: Christian
authors.initials: C
authors.lastname: Richard
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Teboul