Quantifying Occupational Stress in Intensive Care Unit Nurses: An Applied Naturalistic Study of Correlations Among Stress, Heart Rate, Electrodermal Activity, and Skin Temperature

Abstract

Objective To identify physiological correlates to stress in intensive care unit nurses. Background Most research on stress correlates are done in laboratory environments; naturalistic investigation of stress remains a general gap. Method Electrodermal activity, heart rate, and skin temperatures were recorded continuously for 12-hr nursing shifts (23 participants) using a wrist-worn wearable technology (Empatica E4). Results Positive correlations included stress and heart rate (ρ = .35, p < .001), stress and skin temperature (ρ = .49, p < .05), and heart rate and skin temperatures (ρ = .54, p = .0008). Discussion The presence and direction of some correlations found in this study differ from those anticipated from prior literature, illustrating the importance of complementing laboratory research with naturalistic studies. Further work is warranted to recognize nursing activities associated with a high level of stress and the underlying reasons associated with changes in physiological responses. Application Heart rate and skin temperature may be used for real-time detection of stress, but more work is needed to validate such surrogate measures.

Occupational Stress and Burnout among Intensive Care Unit Nurses during the Pandemic: A Prospective Longitudinal Study of Nurses in COVID and non-COVID Units

“…The E4 device continuously records EDA, ST, and blood volume pulse from which heartrate (HR) and inter-beat interval (IBI) were derived. The E4 sensors are considered medical-grade and prior studies have used it for stress detection [34,[41][42][43][44]. A fully charged E4 was given to the participants at the start of each shift and returned at the end of shift.…”

“…Cutoff values were defined for HR and ST to remove artifacts. In line with Ahmadi et al ( 2022) [34], any HR value above 200 bpm and ST values above 45°C were removed, and the averages per minute was computed. A Python script incorporating the Ledapy package [45] was used to correct artifacts and segregate phasic and tonic components of EDA.…”

“…Kubios V3.3.1 was used to calculate SI and EE at 1-minute intervals from the IBI signals. SI is the square root of Baevsky's stress index [47] and relates to the intensity of sympathetic cardiac function, and has been used as an indicator of stress [34,48]. An SI value less than 7 c.u indicates a very low or no stress zone, a value between 7 c.u.…”

“…Phasic EDA-the acute, timevarying spikes in skin conductance level-significantly increases during states of high emotional arousal and stress [32,33]. Though a few studies used physiological indices to measure occupational stress of ICU nurses with promising results [30,34], the studies were cross-sectional rather than comparative.…”

Real-time Stress Monitoring for Intensive Care Unit (ICU) Nurses

“…Real-time physiological measurement (such as wearable sensors) has recently been proposed to monitor changes of stress non-intrusively over time. Eye metrics (e.g., pupil diameters) and activity sensors such as accelerometers have been used to quantify mental and physical stress in real-time (Ahmadi, Sasangohar et al 2022), and machine learning methods have been utilized to monitor stress (Sadeghi, McDonald et al 2022). Our team has recently used various sensors including electrodermal activity (EDA), heart rate, and skin temperature in a naturalistic study of ICU nurses and found significant correlations between the extracted Baevsky's stress index and several physiological variables (Ahmadi et al, 2022).…”