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Published on: April 28, 2014
Probiotics: Prevention of Severe Pneumonia and Endotracheal Colonization Trial-PROSPECT: a pilot trial
Deborah J Cook1,2, Jennie Johnstone3,4,5, John C Marshall6,7
1Department of Medicine, McMaster University, McMaster Health Sciences Center, Room 2C11, 1200 Main Street W, Hamilton, ON, Canada. debcook@mcmaster.ca.
Background:
Probiotics are live microorganisms that may confer health benefits when ingested. Randomized trials suggest that probiotics significantly decrease the incidence of ventilator-associated pneumonia (VAP) and the overall incidence of infection in critically ill patients. However, these studies are small, largely single-center, and at risk of bias. The aim of the PROSPECT pilot trial was to determine the feasibility of conducting a larger trial of probiotics to prevent VAP in mechanically ventilated patients in the intensive care unit (ICU).
Methods:
In a randomized blinded trial, patients expected to be mechanically ventilated for ≥72 hours were allocated to receive either 1 × 10(10) colony-forming units of Lactobacillus rhamnosus GG or placebo, twice daily. Patients were excluded if they were at increased risk of L. rhamnosus GG infection or had contraindications to enteral medication. Feasibility objectives were: (1) timely recruitment; (2) maximal protocol adherence; (3) minimal contamination; and (4) estimated VAP rate ≥10 %. We also measured other infections, diarrhea, ICU and hospital length of stay, and mortality.
Results:
Overall, in 14 centers in Canada and the USA, all feasibility goals were met: (1) 150 patients were randomized in 1 year; (2) protocol adherence was 97 %; (3) no patients received open-label probiotics; and (4) the VAP rate was 19 %. Other infections included: bloodstream infection (19.3 %), urinary tract infections (12.7 %), and skin and soft tissue infections (4.0 %). Diarrhea, defined as Bristol type 6 or 7 stools, occurred in 133 (88.7 %) of patients, the median length of stay in ICU was 12 days (quartile 1 to quartile 3, 7-18 days), and in hospital was 26 days (quartile 1 to quartile 3, 14-44 days); 23 patients (15.3 %) died in the ICU.
Conclusions:
The PROSPECT pilot trial supports the feasibility of a larger trial to investigate the effect of L. rhamnosus GG on VAP and other nosocomial infections in critically ill patients.
Trial Registration:
Clinicaltrials.gov NCT01782755 . Registered on 29 January 2013.
Insights
This pilot study found it is feasible to conduct a large trial on probiotics for preventing ventilator-associated pneumonia (VAP) in intensive care unit (ICU) patients. Lactobacillus rhamnosus GG administration was well-tolerated and achievable in a multi-center setting.
Area of Science:
- Critical care medicine
- Microbiology
- Clinical trials
Background:
- Probiotics, live microorganisms conferring health benefits, are suggested to reduce infections in critically ill patients.
- Previous studies on probiotics for ventilator-associated pneumonia (VAP) are limited by small size, single-center design, and potential bias.
- The PROSPECT pilot trial aimed to assess the feasibility of a larger study on probiotics for VAP prevention in mechanically ventilated intensive care unit (ICU) patients.
Purpose of the Study:
- To determine the feasibility of recruiting patients, maintaining protocol adherence, and minimizing contamination in a large-scale probiotic trial.
- To estimate the VAP rate in mechanically ventilated patients to inform sample size calculations for a future definitive trial.
- To gather preliminary data on other infections, diarrhea, length of stay, and mortality.
Main Methods:
- A randomized blinded trial involving 150 patients expected to require mechanical ventilation for at least 72 hours.
- Patients received either Lactobacillus rhamnosus GG (1×10^10 colony-forming units twice daily) or a placebo.
- Feasibility objectives included timely recruitment, high protocol adherence (≥97%), minimal contamination, and an estimated VAP rate of ≥10%.
Main Results:
- All feasibility goals were met across 14 Canadian and US centers within one year.
- The VAP rate was 19%, exceeding the ≥10% target, with high protocol adherence (97%) and no open-label probiotic use.
- Other observed infections included bloodstream (19.3%), urinary tract (12.7%), and skin/soft tissue infections (4.0%). Diarrhea occurred in 88.7% of patients.
Conclusions:
- The PROSPECT pilot trial successfully demonstrated the feasibility of conducting a larger, multi-center trial on probiotics for VAP prevention.
- Lactobacillus rhamnosus GG administration was feasible and well-tolerated in critically ill, mechanically ventilated patients.
- Findings support further investigation into the efficacy of L. rhamnosus GG for reducing VAP and other nosocomial infections in the ICU setting.
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