Sedation with ketamine during intradiscal electrothermal therapy.
METHODS
A technical report.


OBJECTIVE
To present a new and improved method to sedate patients during intradiscal electrothermal therapy (IDET).


BACKGROUND
The current standard of practice is to sedate patients with short-acting benzodiazepines and opioids during the coagulation phase of intradiscal electrothermal therapy. There are few data on the subject, but it is estimated that between 5% and 20% of IDET procedures are either aborted early or switched to a lower heating temperature because patients cannot tolerate the optimal, recommended heating protocol. A priori, one must assume these patients are more likely to fail their treatment than those who are able to tolerate complete heating.


METHODS
The authors treated 9 patients receiving intradiscal electrothermal therapy who were unable to tolerate the latter portion of their heating protocol secondary to axial low back pain despite high doses of opioids, with low dose ketamine. This paper outlines our experience with "rescue" doses of ketamine, along with the rationale and guidelines for its use.


RESULTS
After receiving ketamine, all patients were able to complete the full intradiscal electrothermal therapy heating protocol. The rescue dosages of ketamine ranged from 15 to 55 mg. The dosages of midazolam used to prevent the psychomimetic effects of ketamine ranged from 3 to 7 mg. Oxygen saturation and hemodynamic parameters did not change significantly after ketamine was administered, and all patients remained responsive throughout the procedure. There were no adverse effects or complications reported.


CONCLUSIONS
When used judiciously to treat axial back pain during intradiscal electrothermal therapy heating, ketamine is a safe and effective rescue medication.
Cohen
Steven P
SP
Pain Management Centers, Department of Anesthesiology, and Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287, USA. spc5_2000@yahoo.com
Larkin
Thomas
T
D000328:Adult; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000627:therapeutic use; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D001416:Back Pain / Q000209:etiology / Q000517:prevention & control; D016292:Procedural Sedation; D004305:Dose-Response Relationship, Drug; D004564:Electrocoagulation / Q000009:adverse effects; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage / Q000627:therapeutic use; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000627:therapeutic use*; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D007431:Intraoperative Complications / Q000517:prevention & control; D007649:Ketamine / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000627:therapeutic use*; D008297:Male; D008874:Midazolam / Q000008:administration & dosage / Q000627:therapeutic use; D017410:Practice Guidelines as Topic; D011292:Premedication; D012585:Sciatica / Q000209:etiology
D018712:Analgesics, Non-Narcotic; D000701:Analgesics, Opioid; D006993:Hypnotics and Sedatives; D007649:Ketamine; D008874:Midazolam; D005283:Fentanyl