A new infrared tympanic thermometer in surgery and anesthesia

Effect of a steam foot spa on geriatric inpatients with cognitive impairment: a pilot study

Purpose

To investigate whether a steam foot spa improves cognitive impairment in geriatric inpatients.

Methods

Geriatric inpatients with cognitive impairment were given a steam foot spa treatment at 42°C for 20 minutes for 2 weeks (5 days/week). Physiological indicators such as blood pressure, percutaneous oxygen saturation, pulse, tympanic temperature, and sleep time and efficiency were assessed. Cognitive function and behavioral and psychological symptoms of dementia were assessed using the Mini-Mental State Examination, Dementia Mood Assessment Scale, and Dementia Behavior Disturbance scale.

Results

Significant decreases in systolic (P < 0.01) and diastolic blood pressure (P < 0.05) along with a significant increase in tympanic temperature (P < 0.01) were observed after the steam foot spas. A significant improvement was seen in the Mini-Mental State Examination score (P < 0.01) and the overall dementia severity items in Dementia Mood Assessment Scale (P < 0.05).

Limitations

Japanese people are very fond of foot baths. However, it is difficult to understand why inpatients cannot receive steam foot baths. In this study, a control group was not used. Raters and enforcers were not blinded.

Conclusion

The results of this pilot study suggest that steam foot spas mitigate cognitive impairment in geriatric inpatients.

Temperature monitoring and perioperative thermoregulation

Most clinically available thermometers accurately report the temperature of whatever tissue is being measured. The difficulty is that no reliably core-temperature-measuring sites are completely noninvasive and easy to use-especially in patients not undergoing general anesthesia. Nonetheless, temperature can be reliably measured in most patients. Body temperature should be measured in patients undergoing general anesthesia exceeding 30 min in duration and in patients undergoing major operations during neuraxial anesthesia. Core body temperature is normally tightly regulated. All general anesthetics produce a profound dose-dependent reduction in the core temperature, triggering cold defenses, including arteriovenous shunt vasoconstriction and shivering. Anesthetic-induced impairment of normal thermoregulatory control, with the resulting core-to-peripheral redistribution of body heat, is the primary cause of hypothermia in most patients. Neuraxial anesthesia also impairs thermoregulatory control, although to a lesser extent than does general anesthesia. Prolonged epidural analgesia is associated with hyperthermia whose cause remains unknown.

The accuracy and precision of four infrared aural canal thermometers during cardiac surgery

BACKGROUND

Four infrared aural canal thermometers are currently available in Japan: Genius, Thermoscan, Quickthermo, and Thermopit. We therefore tested the hypothesis that each is sufficiently accurate and precise for clinical use.

METHODS

For the purpose of this investigation, we considered accuracy to be the mean difference between the test thermometers and the reference thermocouple. Precision was considered to be the standard deviation of the difference between the test and reference values. We evaluated ten patients undergoing cardiopulmonary bypass with moderate hypothermia (approximately 30 degrees C). Aural canal temperatures were measured in random order with each infrared thermometer, and compared with readings from a thermocouple positioned at the contralateral tympanic membrane.

RESULTS

Compared to the thermocouple, the Genius and Thermoscan both had regression slopes > 0.85 and correlation coefficients near 0.87; in contrast, slopes of the Quickthermo and Thermopit regressions were 0.68 and 0.53, respectively. The correlation coefficients for each were < 0.65. The accuracy (offset, or bias) was near 0 degree C with both the Genius and Thermoscan thermometers. In contrast, it was 1.1 degrees C with the Quickthermo and a full 2.3 degrees C with the Thermopit. The precision (standard deviation) of the measurements, however, was approximately 0.8 degree C in each case.

CONCLUSION

We conclude that none of the tested aural canal infrared thermometers was sufficiently accurate and precise for perioperative use.

A comparison of four infrared tympanic thermometers with tympanic membrane temperatures measured by thermocouples

PURPOSE

To compare measurements made with four infrared tympanic thermometers (Genius, Thermopit, Quickthermo, and Thermoscan) with those recorded from thermocouples positioned in the contralateral ear.

METHODS

Four tympanic thermometers were evaluated in 50 healthy volunteers (12 female and 38 male). Temperatures were measured, in random order, at the right tympanic membrane four times and the highest temperature was considered to be the true value measured by each thermometer. The control temperature was measured at the left tympanic membrane using Mon-a-Therm thermocouples.

RESULTS

The tympanic membrane temperature measured by Genius correlated best with the Mon-a-therm measurement (TM) (r = 0.74). The tympanic membrane temperatures measured by Thermopit, Quickthermo, and Thermoscan correlated moderately with TM (r = 0.56, 0.63, and 0.58, respectively). Mean differences between TM and each temperature (TG, TTP, TQ, and TTS) were -0.3, 0.73, 0.42, and -0.3 degrees C, respectively. Likewise standard deviations were 0.33, 0.37, 0.35, and 0.35.

CONCLUSION

We conclude that all but the Thermopit (TTP) are similarly useful for the management of patients during anaesthesia.