Format

Send to

Choose Destination
J Clin Med. 2019 Aug 14;8(8). pii: E1217. doi: 10.3390/jcm8081217.

Ventilator-Associated Pneumonia and PaO2/FIO2 Diagnostic Accuracy: Changing the Paradigm?

Author information

1
Department of Pneumology, Hospital Clinic of Barcelona, August Pi i Sunyer Biomedical Research Institute - IDIBAPS, University of Barcelona, 08036 Barcelona, Spain. miferrer@clinic.cat.
2
Network Centre for Biomedical Research in Respiratory Diseases (CibeRes, CB06/06/0028), Carlos III Health Institute, 28029 Madrid, Spain. miferrer@clinic.cat.
3
Department of Pneumology, Hospital Prof. Doutor Fernando Fonseca, EPE, School of Medicine, University of Lisbon, 2720-276 Lisbon, Portugal.
4
Department of Pneumology, Hospital Clinic of Barcelona, August Pi i Sunyer Biomedical Research Institute - IDIBAPS, University of Barcelona, 08036 Barcelona, Spain.
5
Network Centre for Biomedical Research in Respiratory Diseases (CibeRes, CB06/06/0028), Carlos III Health Institute, 28029 Madrid, Spain.
6
Department of Anesthesiology and Intensive Care Medicine, Fondazione Policlinico Universitario A. Gemelli, Sacred Heart Catholic University, 00168 Rome, Italy.
7
St. James's Hospital, Multidisciplinary Intensive Care Research Organization (MICRO), Dublin D03 VX82, Ireland.
8
Department of Pneumology, Hospital Clinic of Barcelona, August Pi i Sunyer Biomedical Research Institute - IDIBAPS, University of Barcelona, 08036 Barcelona, Spain. atorres@ub.edu.
9
Network Centre for Biomedical Research in Respiratory Diseases (CibeRes, CB06/06/0028), Carlos III Health Institute, 28029 Madrid, Spain. atorres@ub.edu.

Abstract

BACKGROUND:

Ventilator-associated pneumonia (VAP) is associated to longer stay and poor outcomes. Lacking definitive diagnostic criteria, worsening gas exchange assessed by PaO2/FIO2 ≤ 240 in mmHg has been proposed as one of the diagnostic criteria for VAP. We aim to assess the adequacy of PaO2/FIO2 ≤ 240 to diagnose VAP.

METHODS:

Prospective observational study in 255 consecutive patients with suspected VAP, clustered according to PaO2/FIO2 ≤ 240 vs. > 240 at pneumonia onset. The primary analysis was the association between PaO2/FIO2 ≤ 240 and quantitative microbiologic confirmation of pneumonia, the most reliable diagnostic gold-standard.

RESULTS:

Mean PaO2/FIO2 at VAP onset was 195 ± 82; 171 (67%) cases had PaO2/FIO2 ≤ 240. Patients with PaO2/FIO2 ≤ 240 had a lower APACHE-II score at ICU admission; however, at pneumonia onset they had higher CPIS, SOFA score, acute respiratory distress syndrome criteria and incidence of shock, and less microbiological confirmation of pneumonia (117, 69% vs. 71, 85%, p = 0.008), compared to patients with PaO2/FIO2 > 240. In multivariate logistic regression, PaO2/FIO2 ≤ 240 was independently associated with less microbiological confirmation (adjusted odds-ratio 0.37, 95% confidence interval 0.15-0.89, p = 0.027). The association between PaO2/FIO2 and microbiological confirmation of VAP was poor, with an area under the ROC curve 0.645. Initial non-response to treatment and length of stay were similar between both groups, while hospital mortality was higher in patients with PaO2/FIO2 ≤ 240.

CONCLUSION:

Adding PaO2/FIO2 ratio ≤ 240 to the clinical and radiographic criteria does not help in the diagnosis of VAP. PaO2/FIO2 ratio > 240 does not exclude this infection. Using this threshold may underestimate the incidence of VAP.

KEYWORDS:

Intensive care unit; PaO2/FIO2.; nosocomial infection; ventilator-associated pneumonia

Supplemental Content

Full text links

Icon for Multidisciplinary Digital Publishing Institute (MDPI) Icon for PubMed Central
Loading ...
Support Center