Somatosensory Evoked Potential Monitoring Useful
Technique may help prevent position-related peripheral nerve injuries in spinal surgery patients
THURSDAY, March 26 (HealthDay News) -- In patients undergoing lumbosacral spinal surgery, monitoring of upper-limb somatosensory evoked potential may help prevent position-related peripheral nerve injuries, according to a report published in the April issue of The Spine Journal.
Induk Chung, Ph.D., of the Medical Center of Central Georgia in Macon, Ga., and colleagues monitored upper-limb somatosensory evoked potential (SSEP), lower-limb SSEP and electromyography in 230 patients aged 28 to 86.
The researchers found that there was a greater than or equal to 50 percent decrease in amplitude of ulnar SSEP in 10 patients but no significant changes in lower-limb SSEP or electromyography during surgery. Two patients had changes in bilateral limbs and eight in unilateral limbs. For those 10 patients, the average surgical time was 154 minutes, the report indicates.
"Correct positioning provides surgeons with good access to the surgical site, and can decrease potential nerve damage," the authors write. "Even with careful positioning, it is not uncommon that obese patients may still be at risk for upper arm compression, where the ulnar nerve or brachial plexus are at higher risk. In addition, the ulnar nerve exhibits higher sensitivity to stretch or compression compared with the median or radial nerve. Hence, despite efforts to position patients carefully with placement of an elbow pad and adequate perfusion of the upper extremities, postoperative ulnar neuropathy may still result."