Abstract
BACKGROUND: Healthcare workers face elevated infection risks by droplet or airborne transmissible pathogens during close patient care, but objective data on actual exposure patterns are scarce. METHODS: We measured nurse-patient contacts (less than 1.5 metres from the patient's head) using Bluetooth Low Energy transmitters on one respiratory intensive care unit (ICU) (December 2020-February 2021) and one respiratory intermediate care unit (IMU) (August 2021) at a German university hospital. Contact frequency, average duration, and cumulative exposure time per 8-h shift were analysed by ward and work shift. RESULTS: ICU nurses had on average 80.3 contacts per shift (mean duration = 46.8 s); IMU nurses had 27.9 contacts (43.6 s). Cumulative time <1.5 metres was 31.8 min in the ICU vs 9.6 min in the IMU. Exposure peaked during early shifts in both units. Differences between ICU and IMU were statistically significant (P < 0.05; Cohen's d > 1.2). CONCLUSION: This study provides the first objective measurements of nurse-patient exposure in ICU and IMU care. ICU nurses experienced substantially higher frequency and duration of close contacts.