Background

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in patients in ICUs. As demonstrated in a cross-sectional prevalence survey in 1,417 ICUs worldwide, the prevalence of respiratory tract infection was 64% among all patients with nosocomial infections. Estimates of all-cause mortality in patients with VAP range from 20-50% and can be as high as 94% in low- to middle-income countries. VAP prolongs the length of mechanical ventilation by 7.6-11.5 days and prolongs hospitalisation by 11.5 – 13.1 days compared with similar patients without VAP.

The excess cost associated with VAP has been estimated at USD$40,000 per patient in the United States. Given its high prevalence and associated antibiotic usage, VAP is likely to be a key driver of antimicrobial resistance (AMR) in ICUs.

The trial has a stepwise noninferiority–superiority hypothesis, i.e., if noninferiority of short duration, compared with long duration, is shown, statistical tests for superiority will be performed using closed testing methods without requiring adjustment of the significance level for multiple comparisons.

This study includes adult patients (≥18 years old) who satisfy our inclusion criteria for VAP after ≥ 48 hours of mechanical ventilation.

In Nepal, patient recruitment will be from:

1. Patan Academy of Health Science, Patan Hospital, Kathmandu
2. Civil hospital, Kathmandu

Following screening and fulfilling the inclusion/exclusion criteria, the study subject will be recruited within 72 hours. The antibiotic treatment course will be determined according to randomization.

Participants in the intervention (short duration) arm will receive antibiotics for up to 7 days. Antibiotics should be stopped from day 3 to 7 if respiratory cultures are negative and the patients fulfil a set of stringent clinical criteria signifying cardiopulmonary stability for 48 hours.

If the respiratory cultures are positive, patients who fulfil the same set of clinical criteria should have their antibiotics stopped from day 5 to 7. Antibiotics administered via all routes, i.e. intravenous, oral and nebulisation, should be stopped. Randomisation will be carried out when the participants fulfil the clinical stop criteria.

The rationale for stopping antibiotics at the above time points is as follows:

The patients will be screened, randomized and followed up by the Research Medical Officer and Research nurse in the Medical ICU of Patan Hospital, Surgical ICU of Patan hospital and Medical ICU of the Civil Hospital.