Evaluation the Impact of Dry Cupping Therapy on Microvascular Reactivity by Near-infrared Spectroscopy with Vascular Occlusion Test in Healthy Volunteers

Participants rested in a seated position at standard temperature for at least 10 minutes. A blood pressure cuff was applied to the upper arm, and the NIRS device (Covidien INVOS™ 5100C Cerebral/Somatic Oximeter, Dublin) was used to monitor regional oxygen levels in the thenar region of the hand throughout the protocol. After a 3-minute stabilization period, the vascular occlusion protocol commenced: the blood pressure cuff was inflated rapidly within 3-4 seconds to 50 mmHg above the baseline systolic blood pressure and maintained for 3 minutes, then deflated within 1 second. The participant rested for another 10 minutes before a certified cupping therapist placed a plastic therapy cup on the forearm, 5 cm from the medial and lateral epicondyles. The size of the cup was based on the participant's forearm, covering 50% of the area. The cup was vacuumed twice using a manual hand pump and left in place for 5 minutes before the air was released through the valve. Following a 3-minute stabilization period, the vascular occlusion protocol was repeated. During the test, rSO2 values and the time to reach the lowest and highest values were recorded. Using this data, the occlusion slope, recovery slope, and 10-second recovery slope were calculated. The occlusion slope was determined by the formula [(baseline rSO2 - minimum rSO2) / time to lowest rSO2], in %/minute. The recovery slope was calculated as [(minimum rSO2 - maximum rSO2) / time to reach the highest rSO2], in %/second. The 10-second recovery slope was calculated as [(minimum rSO2 - rSO2 at 10 seconds) / 10 seconds].