IONM: The standard of evidence must be both credible and ethical.
Stanley A.Skinner, Neurologist/Neurophysiologist, Abbott Northwestern Hospitaldrskinnermd@yahoo.com
Stan Skinner, Minneapolis, MN; David Rippe, Minneapolis, MN
Submitted April 10, 2012
Drs. Ney and van der Goes [1] do not dispute that unrecovered spinal cord conduction block during monitoring predicts postoperative spinal cord injury (SCI). They rightfully insist that monitoring will prevent SCI. Therefore, those who monitor patients must identify injury when it occurs, relate the presumed injury to a procedural context, and implement a context-driven intervention.
We—and others—have reported these tactics during decompression at spinal cord level. [2] We lost motor evoked potential (MEP) in 15 patients: 4/5 with unrecovered MEP suffered postoperative SCI and 10/10 patients with lost MEP recovered through specific interventions who suffered no deficit. The understudied problem of false positive MEP monitoring must be considered. [3] However, if only 1/10 of our MEP-recovered patients "truly" avoided catastrophic SCI, the monitoring effort was vindicated.
Also, cost-effectiveness analyses [4] suggest that the lifetime cost of one avoided paraplegic age 25 is about $977,000. The avoidance of paraplegia in one patient age 50 may pay for about 250 monitored cases. Patient caregivers, who act also as research scientists, operate under a special burden. The enrollment of patients into randomized trials demands a state of "therapeutic equipoise" between the studied interventions (or non-interventions). Only a "genuine doubt" of efficacy can bioethically justify randomization. [5]
1. Ney, JP, van der Goes D. Updated Practice Guidelines for IOM Fall Short. Neurology published online March 6, 2012.
2. Skinner SA, Transfeldt EE, Mehbod AA, Mullan JC, Perra JH. Electromyography detects mechanically-induced suprasegmental spinal motor tract injury: review of decompression at spinal cord level. Clin Neurophysiol 2009;120:754-764.
3. Langeloo DD, Lelivelt A, Louis Journée H, Slappendel R, de Kleuver M. Transcranial electrical motor-evoked potential monitoring during surgery for spinal deformity: a stude of 145 patients. Spine 2003;28:1043-1050.
4. Sala F, Dvorak J, Faccioli F. Cost effectiveness of multimodal intraoperative monitoring during spine surgery Eur Spine J 2007;16(Suppl 2):S229-231.
5. Kerridge I, Lowe M, Henry D. Ethics and evidence based medicine. BMJ 1998;316:1151-1153.
For disclosures, contact the editorial office at journal@neurology.org.
Drs. Ney and van der Goes [1] do not dispute that unrecovered spinal cord conduction block during monitoring predicts postoperative spinal cord injury (SCI). They rightfully insist that monitoring will prevent SCI. Therefore, those who monitor patients must identify injury when it occurs, relate the presumed injury to a procedural context, and implement a context-driven intervention.
We—and others—have reported these tactics during decompression at spinal cord level. [2] We lost motor evoked potential (MEP) in 15 patients: 4/5 with unrecovered MEP suffered postoperative SCI and 10/10 patients with lost MEP recovered through specific interventions who suffered no deficit. The understudied problem of false positive MEP monitoring must be considered. [3] However, if only 1/10 of our MEP-recovered patients "truly" avoided catastrophic SCI, the monitoring effort was vindicated.
Also, cost-effectiveness analyses [4] suggest that the lifetime cost of one avoided paraplegic age 25 is about $977,000. The avoidance of paraplegia in one patient age 50 may pay for about 250 monitored cases. Patient caregivers, who act also as research scientists, operate under a special burden. The enrollment of patients into randomized trials demands a state of "therapeutic equipoise" between the studied interventions (or non-interventions). Only a "genuine doubt" of efficacy can bioethically justify randomization. [5]
1. Ney, JP, van der Goes D. Updated Practice Guidelines for IOM Fall Short. Neurology published online March 6, 2012.
2. Skinner SA, Transfeldt EE, Mehbod AA, Mullan JC, Perra JH. Electromyography detects mechanically-induced suprasegmental spinal motor tract injury: review of decompression at spinal cord level. Clin Neurophysiol 2009;120:754-764.
3. Langeloo DD, Lelivelt A, Louis Journée H, Slappendel R, de Kleuver M. Transcranial electrical motor-evoked potential monitoring during surgery for spinal deformity: a stude of 145 patients. Spine 2003;28:1043-1050.
4. Sala F, Dvorak J, Faccioli F. Cost effectiveness of multimodal intraoperative monitoring during spine surgery Eur Spine J 2007;16(Suppl 2):S229-231.
5. Kerridge I, Lowe M, Henry D. Ethics and evidence based medicine. BMJ 1998;316:1151-1153.
For disclosures, contact the editorial office at journal@neurology.org.