Clinical trial NCT00671931: Susceptibility of Motor-Evoked Potentials to Varying Targeted Blood Levels of Dexmedetomidine
Official title: Susceptibility of Motor-Evoked Potentials to Varying Targeted Blood Levels of Dexmedetomidine
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
Conditions: Scoliosis
Keywords: dexmedetomidine
neuromonitoring
spine procedures
safe dose
1- safe dose of dexmedetomidine when used in total intravenous anesthesia for procedures require neuromonitoring
2- safe dose of propofol when uses in comination with dexmedetomidine in neuromontoring
3effect of dexmedetomidine on somatosensory evoked potential and motor evoked potentials
Lead sponsor: Children's Hospital Medical Center, Cincinnati
Sponsor class: OTHER
First posted: 2008-05-05
Enrollment: 44
Sex: ALL
Minimum age (years): 10
Maximum age (years): 25
Standard ages: CHILD
ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: FACTORIAL

Brief summary: Reduction of the spinal cord injuries during scoliosis surgery is a major goal of the anesthesia and surgical team. Despite improvement in scoliosis surgery over the years, the development of neurological deficits remains the most feared complication of spine surgery. During scoliosis surgery it is very important to monitor the spinal cord to detect spinal cord injury with surgical manipulation. Continuous or intermittent intraoperative electrophysiological monitoring (neuron-monitoring) is used routinely during these procedures to provide the surgeon with information concerning the integrity of neurological structures at risk. All neuron-monitoring modalities are affected by the anesthetic regimen used. Of the various intravenous anesthetic drugs, the combination of propofol, remifentanil and dexmedetomidine appear to impact neuron-monitoring the least. The current anesthetic practice is to use the three drugs in combination at doses that do not depress the signals but there is no data relating targeted dexmedetomidine and propofol blood levels to neuron-monitoring signals. The lack of data results in wide variability in dosing with consequent variability in patient response.

Hypothesis: Clinically relevant blood levels of dexmedetomidine will affect the amplitude of transcranial motor-evoked potentials (TcMEP) either independently or by interaction with propofol in a dose dependent manner.


Eligibility criteria: Inclusion Criteria:

* Subjects must be 10 to 25 years of age
* Diagnosis of idiopathic scoliosis is established
* Subject's legal authorized representative has given written, informed consent to participate in the study and, where appropriate, the subject has given assent to participate
* American society of Anesthesiology physical status one/two
* Patients scheduled for posterior spinal fusion only

Exclusion Criteria:

* • Patients with neuromuscular scoliosis and patients with motor or sensory deficit in the lower extremities

  * Patients with allergy to, or contraindication for the drugs or techniques used in the study
  * Morbid obesity (Body mass index higher than 40)
  * History of malignant hyperthermia
  * Patient with severe cardiopulmonary disease (pulmonary hypertension, cardiomyopathy, mechanical ventilation)

Primary outcomes:
measure: Motor Evoked Potential Amplitude
timeFrame: baseline, 30 minutes
Secondary outcomes:
Other outcomes:
Locations:
city: Cincinnati
country: United States
facility: Cincinati Children Medical Center
state: Ohio
Study officials:
affiliation: Children's Hospital Medical Center, Cincinnati
name: Mohamed Mahmoud, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Mahmoud M, Sadhasivam S, Salisbury S, Nick TG, Schnell B, Sestokas AK, Wiggins C, Samuels P, Kabalin T, McAuliffe J. Susceptibility of transcranial electric motor-evoked potentials to varying targeted blood levels of dexmedetomidine during spine surgery. Anesthesiology. 2010 Jun;112(6):1364-73. doi: 10.1097/ALN.0b013e3181d74f55.