A 5-year analysis of rapid response system activation at an in-hospital haemodialysis unit

To study the incidence, patient and event characteristics, and outcome of rapid response system (RRS) activation on an in-hospital haemodialysis unit.

Retrospective review of all RRS events on an in-hospital 10-bed haemodialysis unit over a 64-month period (November 2001 to February 2007).

University of Pittsburgh Medical Center Presbyterian Hospital, a 730-bed academic, urban, tertiary care adult hospital in the USA. Interventions None.

Over a 64-month-period, 107 of 8928 patients undergoing haemodialysis on the dialysis unit required an RRS activation (12 events/1000 patients dialysed). The most common reasons for RRS activation were respiratory distress/hypoxaemia (27%) and mental status change (24%). Predictors of in-hospital mortality included old age (33% in-hospital mortality for patients aged 65 years or older vs 14% for patients aged less than 65 years; χ(2) = 5.66, df = 1, p = 0.017), and RRS activation due to a respiratory abnormality (37% mortality for respiratory codes vs 18% for all other codes; χ(2) = 4.12, df = 1, p = 0.042). Surprisingly, only 71% of the patients who had an RRS event had the event as dialysis was occurring. Twenty-four patients (22%) met one or more RRS activation criteria upon first vital sign check in the dialysis unit; RRS was activated on 12 (11%) of these patients before dialysis was started. Nineteen (18%) additional patients had an RRS event after their dialysis session had ended, while awaiting transport back to their unit.

From our findings, it can be suggested that critical events often occur before and after dialysis treatment, during or awaiting transport. Careful assessment of these high-risk patients before and after transport, to and from the dialysis unit may be warranted.