Echocardiographic evaluation and N-terminal pro-brain natriuretic peptide measurement of patients hospitalized for heart failure during weaning from mechanical ventilation.
BACKGROUND
Weaning patients with heart failure who have required mechanical ventilation remains challenging. We evaluated echocardiographic indexes and N-terminal pro-brain natriuretic peptide (NT-proBNP) as markers of acute cardiac dysfunction before and after spontaneous breathing trials (SBT) in such patients to assess their ability to predict subsequent successful extubation.


METHODS
Forty-four patients who underwent their first SBT were prospectively included. Plasma levels of NT-proBNP and transthoracic echocardiography indices including cardiac index, E/A ratio and E/Ea ratio were recorded immediately before commencing and just before the end of SBT.


RESULTS
Ten patients (22.7%) failed their SBT. No significant difference was observed concerning baseline echocardiographic data and NT-proBNP level between the patients who succeeded the SBT or those that failed. Cardiac index increased significantly at end-SBT in patients who passed (3.3 [3.06-3.77] vs. 3 [2.68-3.3] L/min/m(2), P<0.001), whereas it remained unchanged in those that failed. E/Ea ratio (16.8 [8.5-27.3] vs. 10.7 [6.7-20.5], P=0.006) and NT-proBNP level (8199 [3106-10949] vs. 4200 [1855-7125] pg/mL, P=0.004) increased significantly in those who failed the SBT, in contrast to the weaning success group where they remained unchanged.


CONCLUSIONS
Neither NT-proBNP level nor the studied echocardiographic indices before SBT were able to predict SBT outcome in patients presenting with severe heart failure. Failure to increase the cardiac index and increases in both E/Ea ratio and NT-proBNP levels were seen at end-SBT in patients who failed the SBT, and may reflect failure of myocardial reserve to cope with the stress of SBT.
Soins Intensifs Cardiologiques, Plateau de Cardiologie Interventionnelle, CHU de Bordeaux, Hopital Haut-Lévêque, Pessac, France. edouard.gerbaud@chu-bordeaux.fr
E
E
Gerbaud
M
M
Erickson
M
M
Grenouillet-Delacre
M-C
MC
Beauvieux
P
P
Coste
C
C
Durrieu-Jaïs
G
G
Hilbert
Y
Y
Castaing
F
F
Vargas
D000368:Aged; D000369:Aged, 80 and over; D060666:Airway Extubation; D015415:Biomarkers; D015331:Cohort Studies; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging* / Q000209:etiology; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011654:Pulmonary Edema / Q000209:etiology; D016896:Treatment Outcome; D014463:Ultrasonography; D015300:Ventilator Weaning / Q000009:adverse effects*
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain