By Jeremy Groves
The Intensive Care Society’s revised recommendations for preventing Ventilator Associated Pneumonia. If you’re like me you’ll find keeping up with the medical literature a bit of a pain. Too many journals, too many words and not enough information. I thus rejoice when I see evidence based guidance in a quality journal that someone with a good deal more patience than me has painstakingly put together. The latest update to the Society’s recommended bundle of interventions for the prevention of ventilator associated pneumonia by Hellyer and colleagues in the August issue of JICS fits the bill.
Now I know bundles are not every ones cup of tea. We all have opinions, some strongly held, and if they don’t accord with one of the items in the bundle, then there is the risk of ignoring the whole package. Personally I can see the merits of them. Wide spread implementation of best practice can only lead to more impetus to research something better.
So, to the recommendations.
1. Elevation of the head of the bed 30-45 degrees
The evidence would seem to point to completely supine being bad, but elevation between 10 and 45 degrees being advantageous. The authors note the difficulty in maintaining a precise angle.
2. Daily sedation interruption (DSI) and assessment of readiness to extubate
In the studies where DSI was compared to ‘standard care’, DSI was clearly superior, where compared to protocoled weaning regimes, the difference was less clear cut. The authors though come down firmly in favour of DSI preventing over sedation and promoting ‘liberation’ from ventilation.
3. Use of subglottic secretion drainage
In the studies reviewed by the authors there were consistent signals for both reduction in VAP (relative risk reduction of about 0.5) and a reduction in length of stay (1 to 3 days). A recent RCT has also shown a reduction in antibiotic usage.
4. Avoidance of scheduled ventilator circuit changes
Now I find this an interesting one. The evidence would seem to suggest that, the more the circuit is manipulated, the higher the incidence of VAP. One study showed a significant financial benefit with changes only when the circuit was visibly soiled when compared to routine 7 day changes.
Routine oral chlorhexidine is not included in this ‘bundle’. It would appear that the studies that led to its adoptions had a large proportion of cardiac surgery patients included and that, while they may benefit, subgroup analysis suggests the general critical care population did not. The authors recommend continuing good oral hygiene, while noting the concerns of bacteraemia following tooth brushing.
Stress ulcer prophylaxis is not included. The balance of risk between prevention of gastrointestinal bleeding and increased bacterial colonisation secondary to reduced gastric pH is acknowledged. The authors note the potential protective benefits of enteral nutrition and recommend a case by case approach with use of SUP in patients at risk of GI bleeding.
I always like interventions that are simple and save money. Three of the interventions could be said to do that with only the airways with subglottic suction having a cost implication.
All in all a useful, and practically applicable, summary of our current knowledge in this area.
Read the article in JICS.