Wireless Vital Sign Monitoring in Pregnant Women: A Functionality and Acceptability Study

Objective: To test the functionality and acceptability of a wireless vital sign monitor in an inpatient obstetric unit.

Materials and methods: Pregnant women at a U.S. tertiary-care hospital wore a wireless vital sign sensor that captures heart rate, respiratory rate, and temperature. Measurements were compared with vital signs obtained by standard devices. We defined continuous capture of vital signs for 30 min with wireless data transfer to a central monitor as functional success. Acceptability was assessed per the pregnant women and nurses observing the device. Bland-Altman plots were constructed to assess agreement between the wireless sensor and standard measurements.

Results: Thirty of 32 enrolled pregnant women had successful monitoring; 2 cases were stopped early for non-study-related reasons. Comparing wireless sensor and standard measurements, the mean difference (limits of agreement) values at the 25th and 75th percentiles were 1.6 (±13.2) and 4.2 (±18.6) heartbeats/min, 4.2 (±6.1) and 0.7 (±5.4) respirations/min, and 0.02°C (±1.5) and 0.5°C (±1.8), respectively. Most pregnant women found the device comfortable, likeable, and useful (78%, 81%, and 97%, respectively); 80% of nurses found the monitor easy to use, and 84% would recommend it to a patient.

Conclusions: We successfully obtained maternal vital signs using a simple wireless monitor with high acceptability. Well-validated monitors of this nature could significantly alleviate the human resource burden of monitoring during labor and confer greatly desired mobility to laboring pregnant women, although incorporation of blood pressure monitoring will be critical.