Monitoramento da temperatura de recém-nascidos: Desenvolvimento de um dispositivo sem fio e prova de conceito

Abstract

Introduction: The maintenance of the newborn's temperature is one of the most relevant factors for his survival. Maintaining thermal control prevents several complications related to hypothermia and hyperthermia and reduces the chance of dying from different causes. Temperature monitoring systems are common in neonatal intensive care units. However, outside of this environment, the detection of hypothermia is still a challenge. Objective: The objective of the study is to develop a prototype of a neonatal temperature monitoring system to alert thermal uncontrolled. Method: An observational cohort study, the temperature of 21 newborns was monitored in a conventional approach and using a new monitoring system under test. All infants were born with gestational age above 35 weeks, healthy and they were evaluated during rooming-in stay, in a public university maternity hospital. To this proposal, a prototype system consisting of a temperature sensor, a Wi-Fi emitter, data collection, and processing center was developed. The temperature value measured by the prototype was blinded, as well as the warnings of thermal uncontrolled. A bench experiment evaluated the reliability of the temperature sensor comparing measurements by the sensor with a conventional standard thermometer. In a real scenario, the sensor of the prototype was affixed to the skin of the newborn's infra-axillary area, and the temperature was automatically measured every 10 minutes. The performance of the prototype was evaluated by comparing the episodes of thermal uncontrolled of the newborn, detected by the two measurement techniques, considering the closest pair of measures. The total set of measurements recorded in the prototype was also analyzed. Hypothermia was characterized by temperature <36.5ºC and hyperthermia >37.5ºC. The Kappa concordance analysis compared the results of the two measurement approaches. Results: The reliability of the temperature measurements accessed by the prototype and the conventional digital thermometer had an intraclass correlation coefficient = 1. In real scenario of care, the newborns temperature surveillance had average time 22:36 hours. The difference between the 115 pairs of measures performed by nursing in relation to those recorded by the prototype averaged 0.014 ºC (SD = 0.14). Comparing the measurement pairs, hypothermia was detected by nursing in 14 (66.7%) newborns and by the prototype in 15 (71.5%) newborns, Kappa index = 0.889. When all measurements performed by the real-time monitoring system were considered, hypothermia was recorded in 520/2809 (28.8%) measurements, while by the intermittent mode, hypothermia was recorded in 30/115 (26.8%). There were three episodes of hypothermia or hyperthermia detected by the new device, at times not monitored by nursing. Conclusions: Temperature monitoring by a computerized system detected as much thermal abnormalities as the conventional method. The developed prototype showed its potential to offer continuous and simultaneous monitoring to a group of newborns hospitalized in a maternity unit.

Keywords: Infant; Newborn; Monitoring; Skin Temperature; Hypothermia; Wireless Technology