The Applied Research Of Wireless Continuous Body Temperature Monitoring Technology In The Clinical Care Of Critically Ill Patients

Objective:This study was designed to establish a wireless continuous body temperaturemonitoring system in order to explore the implementation approach of wirelesscontinuous body temperature monitoring technology, and provide a scientific basis forimproved methods of temperature monitoring in critically ill patients.Methods:1. We chose Japan Shibaura NTC thermistors PX-42H-S2sensors, AD8290signalamplifier and Texas Instruments TI CC2540radio chip to develop the continuoustemperature monitoring hardware; we chose ApplexCode development tools todevelopwireless continuous body temperature monitoring software based on iOSoperating system. We calibrated the instrument according to the People’s Republicof China National Metrology technical specifications JJF1226-2009‘medicalelectronic thermometer calibration standard’, issued by ChinaGeneralAdministration of Quality Supervision, Inspection and Quarantine.2. We developed wireless continuous temperature monitoring system, recruited100healthy adult volunteers in the study to compare axillary temperature and the innercanthus temperature between our continuous temperature monitoring system andmercury thermometer.3. Select26patients inPLA GeneralHospital sequencely, all these patients wereplanning to take cardiovascular surgery and embed pulmonary artery. Record theircore body temperature (pulmonary artery temperature) and skin temperaturerespectively based on five timestamps: enter ICU(T0), one hour later(T1), twohours later(T2), three hours later(T3), four hours later(T4), five hours later(T5).Using continuous cardiac output monitor to monitor the patient’s pulmonary artery temperature, using wirelesscontinuous temperature monitoring system to monitorbodytemperature of the inner canthus of the skin, axilla, radial artery pulse at thewrist outside the skin, abdominal umbilical connection with the anterior superioriliac spine1/3the skin, the skin at the groin femoral pulse and many other parts ofpatients’ body temperature. We have comparedeach patient’s body temperaturevalues between these measurements methods.4. Select52patients in ICU of PLA General Hospital sequencely, use continuous bodytemperature monitoring system to record their body temperature of inner canthus ofthe skin and axillarespectively based on six timestamps:2:00（T1）、6:00（T2）、10:00（T3）、14:00（T4）、18:00（T5）、22:00（T6）. Compare the result with mercuryfilled glass thermometer record results in same condition, to explore the betterapproach for ICUpatients noninvasive and continuous body temperaturemonitoring.At the same time, from the beginning of T0, record24hours ofcontinuous axillary temperature using wireless continuous temperature monitoringsystemhourly.Results:1. The error of the wireless continuous temperature monitoring system calibrationresults is less than0.05℃.2. Monitoring results from mercury filled glass thermometers and wireless continuoustemperature monitoring system of healthy volunteers’axillary and inside canthustemperature was positively correlated(P <0.05), with good consistency. Monitoringresults from mercury filled glass thermometers on axillatemperature andwirelesscontinuous temperature monitoring system on was positively correlated (P <0.05),with good consistency.3. Monitoring results from wireless continuously temperature monitoring systemmeasured cardiac surgery patients’within canthus skin temperature and pulmonaryartery temperature was positively correlated,(P <0.05), with good consistency.Monitoring results from wireless continuously temperature monitoring system measured cardiac surgery patients’armpit skin temperature and pulmonary arterytemperature was positively correlated,(P <0.05), with good consistency.Monitoringresults from wireless continuously temperature monitoring system on cardiacsurgery patients’wrist radial artery pulse at the skin, the outer spine connection1/3lower abdominal skin before umbilical and iliac, femoral pulse at the groin skintemperature and pulmonary temperature was positively correlated (P <0.05), but therelevance and consistency is poor.4. Monitoring results from wireless continuously temperature monitoring systemmeasured critically illed patients’ armpit and within canthus skin temperature andpulmonary artery temperature was positively correlated,(P <0.05), with goodconsistency.24hours average body temperatureof critically ill patients arepositively correlated (P <0.05) with APACHEII score points, C-reactive protein andinterleukin-6.Conclusion:1. The wireless continuous temperature monitoring system is in line with nationalstandards, showing error is in the specified range.2. The wireless continuous body temperature monitoring system monitoring result inhealthy volunteers has good correlation with axillarytemperature and skintemperature inside canthus measured from mercury filled glass thermometer, can beused to measure body temperature.3. Wireless continuously temperature monitoring system measured axillarytemperature and inside canthus skin temperature has good consistency with thepulmonary artery temperature. Canthus is the best place in the core temperaturesurface monitoring.4. The wireless continuous body temperature monitoring system monitoring result inICU patients has good correlation with axillarytemperature and skin temperatureinside canthus measured from mercury filled glass thermometer, can be used toreplace mercury filled glass thermometer.5. Compare to regular body temperature monitoring, continuous body temperature monitoring is more helpful on in time diagnosis and treatment.