In a small pilot study, scientists in Sweden found that probiotic or so called “friendly” bacteria were just as effective as an antiseptic at reducing pathogenic bacteria that can cause pneumonia in hospital patients on ventilators.
The study was led by Dr Bengt Klarin from the University Hospital in Lund, Sweden and is published this week in the BioMed Central open access journal Critical Care.
The researchers found that the “friendly” probiotic bacterium, Lactobacillus plantarum 299 (Lp299), which is in saliva and also common in fermented foods like pickles and sauerkraut, can out-compete dangerous bacteria that cause respiratory illnesses like pneumonia in patients who are on ventilators.
A solution of friendly bacteria was just as effective at keeping down levels of pathogenic bacteria that commonly cause ventilator-associated pneumonia (VAP) as a solution of normal antiseptic, they said in a press statement.
VAP is a common side effect of being on a breathing machine and occurs when harmful bacteria in the mouth, throat or breathing tube get into the lungs.
The early signs of pneumonia are sometimes missed because people on ventilators can’t communicate or because they are sedated.
As Klarin explained:
“VAP is connected with longer intensive care and hospital stays, additional costs and high mortality. The risk of developing this condition increases by 1% with each additional day of mechanical ventilation.”
For the study, Klarin and colleagues performed a randomized, controlled trial with 50 critically ill patients on mechanical ventilation. They assigned the patients either to receive oral mechanical cleansing followed by washing with 0.1 per cent solution of the antiseptic chlorhexidine (CHX), or the same cleansing procedure followed by oral application of an emulsion of Lp299.
Klarin said:
“We hypothesised that swabbing the mouth with probiotics would be an effective (and microbiologically attractive) method of reducing pathogenic oral microorganisms in intubated, mechanically ventilated, critically ill patients.”
The researchers also took microbiological samples from the throat and windpipe (oropharynx and trachea) of the patients at the start of the trial (inclusion) and at regular intervals afterwards.
The results showed that:
- Potentially pathogenic bacteria that were not present at inclusion were found in throat samples from 8 of the patients washed with Lp299 and 13 with CHX (p = 0.13).
- Tracheal (windpipe) samples showed similar results.
- Lp299 was recovered from the throat samples of all patients in the Lp299 group.
Klarin and colleagues concluded that:
“In this pilot study, we found no difference between the effect of Lp299 and CHX used in oral care procedures, when we examined the effects of those agents on colonisation of potentially pathogenic bacteria in the oropharynx of intubated, mechanically ventilated patients.”
Using Lp299 may also bring other advantages said the researchers such as avoiding some of the common side effects of CHX like tooth discoloration, irritation and sometimes allergic reactions too. Also CHX is diluted by saliva and can lead to resistant harmful bacterial strains.
Lp299 on the other hand did not cause any side effects in this study said the researchers.
“Use of the probiotic Lactobacillus plantarum 299 to reduce pathogenic bacteria in the oropharynx of intubated patients: a randomised controlled open pilot study.”
Bengt Klarin, Göran Molin, Bengt Jeppsson and Anders Larsson.
Critical Care (in press), November 2008.
Sources: Biomed Central.
Written by: Catharine Paddock, PhD.