The use of cusum analysis in the early detection and management of hospital bed occupancy crises.
OBJECTIVE
To assess the value of cusum analysis in hospital bed management.


METHODS
Comparative analysis of medical patient flows, bed occupancy, and emergency department admission rates and access block over 2 years.


METHODS
Internal Medicine Services and Emergency Department in a teaching hospital.


METHODS
Improvements in bed use and changes in the level of available beds.


METHODS
Average length of stay; percentage occupancy of available beds; number of patients waiting more than 8 hours for admission (access block); number of medical patients occupying beds in non-medical wards; and number of elective surgical admissions.


RESULTS
Cusum analysis provided a simple means of revealing important trends in patient flows that were not obvious in conventional time-series data. This prompted improvements in bed use that resulted in a decrease of 9500 occupied bed-days over a year. Unfortunately and unexpectedly, after some initial improvement, the levels of access block, medical ward congestion and elective surgical admissions all then deteriorated significantly. This was probably caused by excessive bed closures in response to the initial improvement in bed use.


CONCLUSIONS
Cusum analysis is a useful technique for the early detection of significant changes in patient flows and bed use, and in determining the appropriate number of beds required for a given rate of patient flow.
Burns
Claire M
CM
Queensland Clinical Practice Improvement Centre, Queensland Health, Brisbane, QLD, Australia.
Bennett
Cameron J
CJ
Myers
Colin T
CT
Ward
Michael
M
D001509:Bed Occupancy / Q000379:methods* / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D006739:Hospital Administration / Q000379:methods* / Q000706:statistics & numerical data; D006742:Hospital Bed Capacity / Q000706:statistics & numerical data; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D011793:Queensland