Fig. 2From: Analgesia effect of premixed nitrous oxide/oxygen during the rehabilitation after total knee arthroplasty: a study protocol for a randomized controlled triala Patient-controlled inhalation of premixed analgesic gas during exercise. b Patient’s pain was evaluated with a Numerical Rating Scale (NRS) during exercise, blood pressure was also measured. c Active range of motion was measured by goniometer and oxygen saturation of blood was monitored after exerciseBack to article page