A computer-controlled, closed-loop infusion system for infusing muscle relaxants: Its use during motor-evoked potential monitoring

Effect of Sugammadex During Transcranial Electrical Motor Evoked Potentials Monitoring in Spinal Surgery: A Randomized Controlled Trial

“…Some teams use partial neuromuscular blockade with successful MEP monitoring 20. This requires careful titration of the neuromuscular blocking drug to a level that achieves partial blockade of monitored twitches (T1 height between 5% and 50% of baseline or a TOF response with 2 of 4 twitches) using a closed-loop continuous infusion system 18,21–24. Closed-loop systems could result in better control of a given target within a selected range and decrease the risk of overshooting or undershooting the target 22.…”

“…20 This requires careful titration of the neuromuscular blocking drug to a level that achieves partial blockade of monitored twitches (T1 height between 5% and 50% of baseline or a TOF response with 2 of 4 twitches) using a closed-loop continuous infusion system. 18,[21][22][23][24] Closed-loop systems could result in better control of a given target within a selected range and decrease the risk of overshooting or undershooting the target. 22 In our study, a closed-loop muscle relaxant infusion system to maintain 2 twitches in the TOF was used; the TOF ratio ranged from 78.5% to 96.8% after the dura was opened.…”

Continuous Monitoring of Cerebrospinal Fluid Oxygen Tension in Relation to Motor Evoked Potentials during Spinal Cord Ischemia in Pigs

“…23 Possibly, this amplitude variability depends on the partial muscle relaxation that is a minimal requirement for myogenic evoked potential recording. 3 Partial Pressure of Oxygen Progressive SCI was associated with a median decrease of CSF PO 2 to 32% of baseline, corresponding with absolute values between 9 and 27 mmHg. The observed decreases in CSF PO 2 are in agreement with previously reported data in animal models of SCI 8,24 and focal cerebral ischemia 25 and are also similar to transient decreases in brain tissue oxygenation during cerebrovascular occlusion in patients.…”

“…Myogenic transcranial motor evoked potentials (tcMEPs) allow fast and reliable assessment of the integrity of motor tract conduction. 1,2 However, the movement artifacts that are associated with partial neuromuscular blockade, 3 the delivery of high-voltage stimuli to the brain, and the complexity of the technique might hamper the use of tcMEP in neurosurgical and critical care environments. Continuous assessment of parenchymal oxygenation via implanted microprobes is used clinically to detect cerebral ischemia after traumatic brain injury, 4 -6 but direct measurement of spinal cord tissue oxygenation is not feasible with the current technology.…”

Delayed detection of motor pathway dysfunction after selective reduction of thoracic spinal cord blood flow in pigs

“…Partial muscle relaxation balances the surgical considerations of patient immobility and movements after transcranial stimulation and the minimal requirements for myogenic evoked potentials recording. 28,29…”