Predictors of failure of noninvasive positive pressure ventilation in patients with acute hypoxemic respiratory failure: a multi-center study.
BACKGROUND
In patients with hypoxemic acute respiratory failure (ARF), randomized studies have shown noninvasive positive pressure ventilation (NPPV) to be associated with lower rates of endotracheal intubation. In these patients, predictors of NPPV failure are not well characterized.


OBJECTIVE
To investigate variables predictive of NPPV failure in patients with hypoxemic ARF.


METHODS
Prospective, multicenter cohort study.


METHODS
Eight Intensive Care Units (ICU) in Europe and USA.


METHODS
Of 5,847 patients admitted between October 1996 and December 1998, 2,770 met criteria for hypoxemic ARF. Of these, 2,416 were already intubated and 354 were eligible for the study.


RESULTS
NPPV failed in 30% (108/354) of patients. The highest intubation rate was observed in patients with ARDS (51%) or community-acquired pneumonia (50%). The lowest intubation rate was observed in patients with cardiogenic pulmonary edema (10%) and pulmonary contusion (18%). Multivariate analysis identified age > 40 years (OR 1.72, 95% CI 0.92-3.23), a simplified acute physiologic score (SAPS II) > or = 35 (OR 1.81, 95% CI 1.07-3.06), the presence of ARDS or community-acquired pneumonia (OR 3.75, 95% CI 2.25-6.24), and a PaO2:FiO2 < or = 146 after 1 h of NPPV (OR 2.51, 95% CI 1.45-4.35) as factors independently associated with failure of NPPV. Patients requiring intubation had a longer duration of ICU stay ( P < 0.001), higher rates of ventilator-associated pneumonia and septic complications ( P < 0.001), and a higher ICU mortality ( P < 0.001).


CONCLUSIONS
In hypoxemic ARF, NPPV can be successful in selected populations. When patients have a higher severity score, an older age, ARDS or pneumonia, or fail to improve after 1 h of treatment, the risk of failure is higher.
Antonelli
M
M
Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Policlinico A. Gemelli, Largo A. Gemelli 8, 00168 Rome, Italy. max.antonelli@flashnet.it
Conti
G
G
Moro
M L
ML
Esquinas
A
A
Gonzalez-Diaz
G
G
Confalonieri
M
M
Pelaia
P
P
Principi
T
T
Gregoretti
C
C
Beltrame
F
F
Pennisi
M A
MA
Arcangeli
A
A
Proietti
R
R
Passariello
M
M
Meduri
G U
GU
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal; D007558:Italy; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012131:Respiratory Insufficiency / Q000628:therapy*; D012307:Risk Factors; D013030:Spain; D018709:Statistics, Nonparametric; D013714:Tennessee; D017211:Treatment Failure