title: Hospital outcomes associated with introduction of a two-tiered response to the deteriorating patient.
abstract: BACKGROUND
  Liverpool Hospital introduced the medical emergency team system in 1990 and it has recently been adopted at a national and international level. New South Wales, Australia, has introduced a standardised rapid response system in over 250 acutecare hospitals: the two-tiered (clinical review call [CRC] and rapid response call [RRC]) "between the flags" (BTF) program.
  
  
  OBJECTIVE
  To describe the effect of the introduction of a twotiered response to the deteriorating patient on the number of RRCs, cardiac arrests and hospital deaths.
  
  
  METHODS
  Our study was undertaken at an 850-bed teaching hospital in the south-west of Sydney, Australia, with about 80 000 hospital admissions each year. Rates of RRCs, cardiac arrests and all hospital deaths (with and without not-for-resuscitation orders) were compared before the introduction of the BTF program (2009) and after implementation, until June 2013. The rates of CRCs after implementation were measured. Changes in the reasons for RRCs were also compared for the 12-month period before and the 36 months after the introduction of the BTF program.
  
  
  RESULTS
  The monthly rate of RRCs before introduction of the program was 18.8 per 1000 hospital admissions (95% CI, 17.8- 19.8 per 1000 admissions) and was estimated to increase by 4% after program implementation (95% CI, 3.2%-4.7%; P < 0.001). The rate of CRCs increased by 13.2% (95% CI, 10.9%-15.6%) during the study period. The cardiac arrest rate before implementation of clinical review was 1.1 per 1000 admissions (95% CI, 0.9-1.3 per 1000 admissions) and after implementation was estimated to have changed by 1% (95% CI, - 1.9 to 3.9; P = 0.48). The hospital death rate before implementation of the BTF program was 10.8 per 1000 admissions (95% CI, 10.1-11.5 per 1000 admissions), and after implementation was estimated to increase by 2% (95% CI, 1.2%-3%, P < 0.001). The reasons for RRCs before and after the introduction of the BTF program did not change (all P values > 0.2), apart from the "worried" criterion, that decreased from 30% to 17% of all calls after implementation (P < 0.001).
  
  
  CONCLUSIONS
  After introduction of the BTF program, there was a progressive increase in documented CRCs and an increase in RRCs. There was no decrease in cardiac arrests or hospital deaths. RRCs based on objective physiological criteria increased. More research is needed to evaluate two-tiered response systems.
authors.affiliation: Intensive Care Liverpool Hospital, Sydney, NSW, Australia. s.frost@uws.edu.au.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Frost
authors.affiliation: Intensive Care Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Amanda
authors.initials: A
authors.lastname: Chapman
authors.affiliation: Intensive Care Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Anders
authors.initials: A
authors.lastname: Aneman
authors.affiliation: South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Jack
authors.initials: J
authors.lastname: Chen
authors.affiliation: Intensive Care Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Parr
authors.affiliation: Intensive Care Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Ken
authors.initials: K
authors.lastname: Hillman
mesh_terms: D000328:Adult; D001315:Australia; D003422:Critical Care / Q000458:organization & administration*; D016638:Critical Illness / Q000401:mortality* / Q000628:therapy; D006323:Heart Arrest / Q000453:epidemiology*; D017052:Hospital Mortality; D057209:Hospital Rapid Response Team / Q000458:organization & administration*; D006760:Hospitalization; D006784:Hospitals, Teaching; D006801:Humans; D015397:Program Evaluation; D012151:Resuscitation