Psychological and physiological effects of warm posterior neck compression in restricted supine position

Objective: This study aimed to investigate the psychological and physiological effects of applying a hot pack to the posterior neck while in a restricted supine position. Methods: In the hot pack (HP) method, a hot compress at approximately 41°C was applied to healthy adults for 30 min after 60 min of supine restraint and compared with the control (CR) method. Psychological effects were assessed using the POMS2 Japanese shortened adult version to measure the mood before and after treatment. Physiological parameters, including body temperature, blood pressure, pulse rate, heart rate variability (HRV) as an autonomic index, and skin surface temperature, were also measured. Results: The results showed that the HP method significantly decreased fatigue and lethargy, whereas the CR method decreased tension and anxiety and increased friendship scores. HRV analysis revealed that the HP method tended to suppress sympathetic nerve activity more than the CR method, although the difference was not statistically significant. There were no significant differences in the physiological parameters between the two methods; however, the skin surface temperature was significantly higher with the HP method at 70, 80, and 90 min. Conclusions: Warm posterior neck compression does not cause changes in the circulatory system and is safe for patients in the supine position for prolonged periods. Although it alleviates negative mood states, it is not strong enough to conclude that it inhibits sympathetic nervous system activity.