Understanding heart rate alarm adjustment in the intensive care units through an analytical approach

<div><p>Background</p><p>Heart rate (HR) alarms are prevalent in ICU, and these parameters are configurable. Not much is known about nursing behavior associated with tailoring HR alarm parameters to individual patients to reduce clinical alarm fatigue.</p><p>Objectives</p><p>To understand the relationship between heart rate (HR) alarms and adjustments to reduce unnecessary heart rate alarms.</p><p>Methods</p><p>Retrospective, quantitative analysis of an adjudicated database using analytical approaches to understand behaviors surrounding parameter HR alarm adjustments. Patients were sampled from five adult ICUs (77 beds) over one month at a quaternary care university medical center. A total of 337 of 461 ICU patients had HR alarms with 53.7% male, mean age 60.3 years, and 39% non-Caucasian. Default HR alarm parameters were 50 and 130 beats per minute (bpm). The occurrence of each alarm, vital signs, and physiologic waveforms was stored in a relational database (SQL server).</p><p>Results</p><p>There were 23,624 HR alarms for analysis, with 65.4% exceeding the upper heart rate limit. Only 51% of patients with HR alarms had parameters adjusted, with a median upper limit change of +5 bpm and -1 bpm lower limit. The median time to first HR parameter adjustment was 17.9 hours, without reduction in alarms occurrence (p = 0.57).</p><p>Conclusions</p><p>HR alarms are prevalent in ICU, and half of HR alarm settings remain at default. There is a long delay between HR alarms and parameters changes, with insufficient changes to decrease HR alarms. Increasing frequency of HR alarms shortens the time to first adjustment. Best practice guidelines for HR alarm limits are needed to reduce alarm fatigue and improve monitoring precision.</p></div

Descriptive statistics of patients with heart alarm parameters changed and unchanged.

<p>Descriptive statistics of patients with heart alarm parameters changed and unchanged.</p

Relationship between number of alarms per hour before HR alarm setting change (log scale) and the hours from first alarm to change in HR alarm setting change (log scale).

<p>When the alarm frequency is higher, there was less delay in adjusting the HR alarm limits.</p

Unit-based summary showing heart rate alarm metrics and parameter settings.

<p>Unit-based summary showing heart rate alarm metrics and parameter settings.</p

Occurrence of alarms and alarm adjustments in the HR vital files.

<p>The occurrence of alarms is indicated by a green * while the alarm adjustment is indicated by the orange square. The pink dotted lines represent the default lower and upper limits.</p

Hospital infrastructure to automatically store all physiologic monitor waveform and alarm data.

<p>Hospital infrastructure to automatically store all physiologic monitor waveform and alarm data.</p

False apnea alarm in a patient breathing adequately on mechanical ventilation.

<p>The respiratory waveform (bottom tracing labelled “Resp”) has a flat line appearance. The detection of respirations from the ECG lead (impedance method) is inaccurate in this patient, displaying an erroneous respiratory rate of 4 per minute.</p

ST-Segment Alarm Durations in a 16-Bed Cardiac ICU.

<p>ST-Segment Alarm Durations in a 16-Bed Cardiac ICU.</p

Schema for Counting and Reporting Physiologic Monitor Device Alarms.

<p>CVP = central venous pressure; RAP = right atrial pressure; PAP = pulmonary artery pressure; LAP = left atrial pressure; ART = invasive arterial line; FEM = invasive arterial line in femoral site.</p><p>Schema for Counting and Reporting Physiologic Monitor Device Alarms.</p

Alarm Default Settings for Adult ICUs during the Study Period.

<p>Alarm Default Settings for Adult ICUs during the Study Period.</p