Improvement in clinical outcomes following institution of dedicated critical care support in the high-dependency unit

Introduction

A recent Scottish Medical and Scientific Advisory Committee report has recommended greater intensivist input into high-dependency units (HDUs). At Stirling Royal Infirmary, patients in the HDU remained under speciality team care, in an open unit model, leading to significant inconsistencies in quality of care. In December 2007 a closed unit policy was implemented with intensivists providing clinical leadership of the unit. We hypothesized that having a single team responsible for all HDU patients would improve continuity of care, with this being reflected in clinical outcome.

Methods

The Scottish Intensive Care Society's database, Wardwatcher™, was used to retrospectively gather data from the 12 months preceding, and 12 months following critical care involvement in the HDU. We investigated three outcome measures of patients who required transfer to the ICU from the HDU during these periods: requirement for renal replacement therapy (RRT), length of stay (level 3 days), and ICU mortality.

Results

Following critical care involvement in the HDU, the total number of HDU admissions per annum fell from 1,372 to 1,197, allowing for the closure of two HDU beds. Ninety-three patients were transferred to the ICU from the HDU in the pre-change 12 months, compared with 67 subsequently. There were no significant differences in age, APACHE II scores, or requirement for mechanical ventilation. The requirement for RRT decreased significantly from 32% to 16% (P = 0.02). This alone is associated with a cost saving of between £15,000 and £25,000. The mean length of stay (level 3) reduced from 7.0 days to 6.0 days, which in combination with the reduction in ICU admissions saved 250 level 3 bed-days over 12 months. Finally there was a trend towards reduced ICU mortality (31% vs. 19%, P = 0.09).

Conclusion

Implementing a critical-care-led closed unit policy in the HDU was associated with an immediate reduction in both HDU and ICU bed-days, allowing planned bed closures. There was a significant reduction in need for RRT and a trend towards reduced ICU mortality. Finally this organisational change has been carried out with significant cost savings that are likely to be sustained.