Use of single patient rooms to decrease acquisition of antibiotic-resistant bacteria in the ICU

Introduction

The role of isolation rooms in decreasing bacterial transmission between ICU patients has been debated. A recent change in ICU location allowed for further investigation.

Methods

Old ICU A and Old ICU B were open-plan seven-bed and four-bed units. In March 2007, ICU A moved to single patient rooms (New ICU A - eight beds). ICU B remained unchanged (New ICU B). The same physicians cover both ICUs. Patient distribution is based on available space only. Demographic and microbiological data were collected on consecutive patients staying >48 hours. Culture of resistant organisms (MRSA, VRE, ESBL, resistant Acinetobacter, or carbapenem-resistant Gram-negatives) in surveillance or clinical cultures was measured. New ICU A was compared with open-plan New ICU B to assess the effect of single rooms. New ICU A was compared with Old ICU A to assess change vs historical controls and New and Old ICU B were compared with show control group stability.

Results

Data were collected on 62, 62, 44 and 39 patients from Old ICU A, New ICU A, Old ICU B and New ICU B. Patient populations in New ICU A and B were similar. ICU acquisition of resistant organisms was lower in New ICU A (3/62, 5% vs 7/39, 18% New ICU B patients, P = 0.043). This finding was confirmed using survival analysis (P = 0.011). Comparing New with Old ICU A showed lower APACHE II scores (18 ± 9 vs 21 ± 9, P = 0.028), pre-ICU antibiotic use (20/62, 32% vs 37/62, 60%, P = 0.001), pre-ICU hospital admission (21/62, 34% vs 37/62, 60%, P = 0.004) and ICU admission prevalence of resistant organisms (11/62, 18% vs 25/62, 40%, P = 0.006). On Cox regression only the admitting ICU was significant for acquisition of resistant organisms (Old vs New ICU A: HR 4.07, 95% CI 1.03 to 16.06, P = 0.025). Comparing New with Old ICU B showed no changes. Adequate hand hygiene amongst the same physicians was found on 140/242 (58%) occasions in New ICU A vs 23/66 (35%) in New ICU B (P < 0.001).

Conclusions

The change in ICU design to single patient rooms significantly decreased acquisition of multiresistant organisms. Whether the ICU design or improved infection control awareness led to change could not be determined. This is the first study to measure the effect of ICU design on acquisition of a range of resistant organisms while including a contemporaneous control ICU environment.