Preventing code blue false alarms through a simple design change: a case study

To the Editor: Recognising and responding to deteriorating patients is essential for mitigating morbidity and mortality.¹ Hospitals worldwide have implemented code blue calls that are activated in response to episodes of patient deterioration, such as a cardiac arrest. This activation is typically through calling an internal emergency number or pressing an emergency alert button. In Australia, the design of these buttons was regulated by a national standard; however, it did not include specifications such as the inclusion of protective covers to prevent false alarms.² Currently, there is no standard to guide the design of these buttons. Here, we present a case study of an Australian hospital and describe how emergency alert buttons installed in line with the national standard affected the costs and frequency of code blue false alarms.

We conducted a retrospective analysis of data from an existing code blue database in an Australian hospital previously described.³ All code blue calls between 1 January 2016 and 31 December 2019 were included. False alarms were code blue calls resulting from an accidental button press, determined by ward staff who then notified the response team upon their arrival. On 24 January 2017, the old hospital building was decommissioned, and all clinical care moved to a new building on an adjacent site. We compared three periods. Firstly, before this move, when all emergency alert buttons had plastic protective covers, the period in the new hospital when no covers were in place, and then the period when covers had been retrofitted to buttons in the new hospital due to the increase in false alarms. A further change was that 3 months after the move to the new building, pull cords in patient bathrooms were reprogrammed to not trigger a code blue when used, but this is not the focus of this letter.

To quantify the change in false alarms, we calculated the average weekly number of true and false alarm code blue calls for each of the three periods. In addition, we undertook an analysis of the financial costs of attending false alarms. A 15-minute attendance duration at each false alarm was assumed. Staff costs were based on the pay rates in 2020 for the response team — three third-year doctors and two nurses.^4,5 Annual costs were presented assuming false alarm rates during the relevant period remained constant for 12 months.

Rates of true and false alarm code blue calls in the old hospital building were 0.95 and 0.59 per week respectively. In the new hospital site, before retrofitting button covers, the rate of false alarms increased to 9.02 per week, representing a 15-fold increase. During this period, only one in 6.1 code blue calls was a true event. After the retrofit of covers was completed, the rate of false alarms decreased to 3.01 per week, which was an improvement of one in 2.4 code blue calls relating to a true activation (Figure 1). At the old hospital site, the annual cost for attending false alarms was $2096. At the new site, before retrofitting the covers, the equivalent annual cost was $31 850. Once the retrofit of covers was completed, the annual cost decreased to $10 632. Cover retrofitting cost $21 279; therefore, cost recovery occurred after 366 days. For the period in the new hospital without covers, a total of 14.7 work weeks would have been spent attending false alarms if the rate had remained constant for one year.

Figure 1.

Average weekly number of false alarms over time (January 2016 – December 2019). The solid line refers to false alarm code blue events, the dotted line refers to true code blue events

Based on this case study, we have identified the high number of false alarms and high staff costs associated with installing hospital emergency alert buttons according to the national standards. High rates of false alarms may desensitise critical care responses and increase staff workload, while also unnecessarily increasing the cost of responding to code blue calls.⁶ Overall, building standards need to mandate designs that mitigate false alarms. In the interim, we believe the installation of protective covers on all emergency alert buttons should be considered for all new hospitals.

Competing interests

None declared.