Twitch potentiation: a potential source of error during neuromuscular monitoring with acceleromyography in anesthetized dogs

T1 increased significantly during 20 minutes of uninterrupted TOF stimulation in the absence of NMB, establishing that twitch potentiation occurs in anesthetized dogs. With no time for potentiation, T1 increased during the course of recovery from NMB; this phenomenon introduces a bias in T1 measurements and could affect studies reporting potency and duration of NMB based on T1 or single twitches. TOFR was unaltered by potentiation emphasizing its clinical usefulness for excluding post-operative residual NMB.