Double burst stimulation for monitoring profound neuromuscular blockade: a comparison with posttetanic count and train of four.

Double burst stimulation (DBS) is a new nerve stimulation pattern introduced to facilitate tactile evaluation of recovery from neuromuscular blockade. DBS consists of two bursts of high frequency stimulations separated by a short time interval. The relationships between DBS, post-tetanic count (PTC) and train-of-four (TOF) on the evoked twitch response was investigated in 16 surgical patients and 7 intensive care patients given atracurium for muscle relaxation. A significant correlation between the twitch height of the first response to DBS and the number of post-tetanic responses was demonstrated when PTC was more than five (r = 0.47, p < 0.0003). When the first twitch of TOF was still not measurable, the first twitch of DBS ranged from 0 to 20% of the TOF-control twitch height. Furthermore the DBS ratio was significantly correlated to the TOF ratio (r = 0.92-0.96, p < 0.0002). It is concluded that DBS not only can be used for monitoring of recovery from neuromuscular blockade, but also for monitoring of intense degrees of neuromuscular blockade.