Abstract:
Context:
Patients in the intensive care unit (ICU) are at risk not only from their critical illness but also from secondary processes such as nosocomial infection. Pneumonia is the second most common nosocomial infection in critically ill patients. Indeed, diagnosis of ventilator associated pneumonia (VAP) requires a high clinical suspicion combined with bedside examination, radiographic examination, microbiologic analysis of respiratory secretions, and blood test.
Aims: This study aimed to evaluate the effectiveness and accuracy of lung ultrasound for VAP diagnosis and follow-up.
Settings and Design: A prospective cohort study was done on 74 patients, with total number of 54 with high likelihood of VAP and 20 with low likelihood of VAP
Methods and Material:Mechanically ventilated patients for 48 hours or more were included. We calculated Clinical pulmonary infection score and Lung Ultrasound was performed within 24 hours.
Statistical analysis used:Data were collected and analyzed by using SPSS (Statistical Package for the Social Science, version 20, IBM, and Armonk, New York). Quantitative data were expressed as mean ± standard deviation (SD) and compared with Student t test. Nominal data were given as number (n) and percentage (%). Chi2 test was implemented on such data.
Results:
Based on Clinical pulmonary infection score (CPIS) with cutoff point (≥ 6), the sensitivity of transthoracic ultrasound was 81.5%, the specificity was 82% and the accuracy was 81.6%. Regarding sonographic signs, the highest sensitivity was for sub-pleural dots of consolidation 82%, then B-lines 56%, followed by pleural effusion and air bronchogram both 19%. Highest specificity was for air bronchogram 100%, then B-lines and pleural effusion both 90%, followed by sub-pleural dots of consolidation 80%. Positive predictive value for transthoracic ultrasound was 92%, Area under the receiver operation characteristics (ROC) curve (AUC) for total ultrasound score was 0.82.
Conclusions: Transthoracic ultrasound is an easy bedside tool for diagnosis and follow up of ventilator associated pneumonia.
Key-words: Ventilator associated pneumonia, Clinical pulmonary infection score, Lung Ultrasounds, intensive care unit
Key Messages:
Transthoracic ultrasound is a useful and convenient bed-side tool for diagnosis and follow up of ventilator associated pneumonia. It should be established as a reasonable tool in early diagnosis due to its availability, being easy to use and low cost. This helps in starting early treatment with antimicrobial therapy.
