Echocardiographic diagnosis of pulmonary artery occlusion pressure elevation during weaning from mechanical ventilation

Crit Care Med. 2009 May;37(5):1696-701. doi: 10.1097/CCM.0b013e31819f13d0.


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).

Measurements and main 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%.

Conclusion: 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Arterial Occlusive Diseases / diagnostic imaging*
  • Arterial Occlusive Diseases / etiology
  • Arterial Occlusive Diseases / mortality
  • Blood Gas Analysis
  • Catheterization, Swan-Ganz
  • Cohort Studies
  • Critical Care / methods
  • Critical Illness / mortality
  • Critical Illness / therapy
  • Echocardiography, Doppler, Pulsed*
  • Female
  • Hemodynamics / physiology
  • Humans
  • Intensive Care Units
  • Male
  • Middle Aged
  • Observer Variation
  • Predictive Value of Tests
  • Probability
  • Prognosis
  • Pulmonary Edema / etiology
  • Pulmonary Edema / prevention & control
  • Pulmonary Wedge Pressure*
  • Respiration, Artificial / adverse effects
  • Respiration, Artificial / methods*
  • Respiratory Insufficiency / diagnosis
  • Respiratory Insufficiency / mortality
  • Respiratory Insufficiency / therapy
  • Risk Assessment
  • Sensitivity and Specificity
  • Severity of Illness Index
  • Survival Analysis
  • Ventilator Weaning / adverse effects
  • Ventilator Weaning / methods*
  • Ventricular Dysfunction, Left / diagnostic imaging*
  • Ventricular Dysfunction, Left / etiology
  • Ventricular Dysfunction, Left / mortality