Good design vs. bad bugs

Graphic:  TM Osborn Associates

A new paper in Critical Care (full text here) attempts to evaluate whether improved ICU design has an impact on transmission of epidemiologically important pathogens, such as VRE and MRSA. The authors compare the proportion of patients acquiring these pathogens before and after an ICU moved from an open unit to one with all private rooms, and also compared this to another ICU that maintained an open floor plan during the study period. In the ICU that moved to all private rooms, the proportion of patients acquiring a targeted pathogen fell from 23% to 5%, whereas in the control ICU there was no change (20% in the corresponding pre-move period, and 18% in the post-move period). So the authors conclude that better ICU design leads to fewer infections.

The study has a number of problems--it's small and relatively short. Moreover, in the intervention ICU, prior to the move the patients were sicker, had received more antibiotics prior to ICU admission, and had a higher prevalence of multidrug-resistant organisms on admission. All of these factors could be responsible for the higher proportion of patients acquiring the bad bugs in the "old" ICU, making the "new" ICU look better than perhaps it was. Also, importantly, hand hygiene compliance was significantly higher in the intervention ICU than in the control ICU in the post-move period, though one could argue that improved hand hygiene was due to better design (e.g., better availability of sinks).

While I remain unconvinced regarding the conclusions of this particular study, it seems to me that for many reasons having ICUs with all private rooms is a good thing. Infection prevention, since time immemorial has been about separating clean from dirty and infected from uninfected. It just makes sense--kind of like not wearing the same dirty white coat to work every day.