Do Liquid Crystal Thermometers Provide an Accurate Representation of Core Temperature in Surgical Trauma Patients? A Study Comparing Liquid Crystal Skin Thermometer and an Esophageal Temperature Probe

Abstract

Temperature monitoring in an ASA standard of care for all patients undergoing any type of operation in the United States. Temperature measurement is essential in victims of trauma because they are exceptionally vulnerable to the detrimental effects of hypothermia. General anesthesia is known to worsen hypothermia, especially in trauma patients. As a result, both core temperature measurement and maintenance are vital to the long-term survival of surgical trauma patients. This study compared the trends of two different types of temperature measurement during surgical trauma operations. Similar studies have previously been performed in healthy, general surgery patients, but this is the first time such a study was performed on trauma patients. In surgical trauma cases at Hurley Medical Center, an esophageal temperature probe is the most frequently used device, despite the absence of research supporting this practice for trauma patients. In this study, an esophageal thermometer was inserted into the distal one-third of the esophagus, representing core temperature, and was simultaneously compared to a liquid crystal skin probe placed on the forehead. Attempts were made to compare the efficacy, accuracy, and cost effectiveness of the liquid crystal skin thermometer compared to the esophageal probe, in addition to a comparison o f the degree of difference in temperature readings over time. Subject enrollment consisted of 12 Level I and II trauma patients, age 18 and older, who underwent surgery under general anesthesia at Hurley Medical Center. Inclusion and exclusion criteria were followed according to protocol, with waived informed consent per approval by the IRB. The study failed to achieve statistical significance due to the small sample size. The liquid crystal skin thermometer failed to produce readings on 6 of the 12 subjects, due to temperature readings below 35° C. Four of the six subjects displayed liquid crystal skin temperature readings that trended accurately with the esophageal temperature probe over time. A larger sample size may have demonstrated that the liquid crystal skin thermometer is a cost-effective, reliable representation o f mean core temperature trending over time in surgical trauma pa tients. Multiple factors have been identified in relation to the unsuccessful enrollment of subjects in regards to this study.