Low-Dose Ketamine Infusions for Highly Opioid-Tolerant Adults Following Spinal Surgery: A Retrospective Before-and-after Study.
Managing acute-on-chronic pain in opioid-tolerant individuals is complex and challenging; exploring new analgesia regimens for this population is essential. Ketamine is an N-methyl D-aspartate antagonist that blocks transmission of painful stimuli and could be a useful medication for this patient population. A new low-dose ketamine protocol as an adjunct to conventional pain therapy was implemented in a major urban Level 1 trauma center in Canada. A retrospective before-and-after chart review was conducted to explore the research question, "What is the effect of low-dose ketamine continuous intravenous infusions on pain of highly opioid-tolerant adults following spinal surgery?". All patients had spine surgery, used a minimum of 100 mg daily oral morphine equivalent preoperatively and were followed postoperatively by the hospital's Acute Pain Service. Data from individuals treated with conventional therapy during the year prior to protocol implementation were compared with data from patients who received conventional therapy plus ketamine post implementation. Outcome measures included pain scores and daily opioid consumption on postoperative days 0 through 5, time to ambulation, time to discharge, and adverse effects. There were no statistically significant differences between conventional therapy and conventional therapy plus ketamine. Ketamine may still be of benefit to patients with acute-on-chronic pain, although this was not evident in this study. Future research using more robust assessment tools to determine effectiveness of ketamine is required.
Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada; Acute Pain Service, Alberta Health Services, Foothills Medical Centre, Calgary, Alberta, Canada. Electronic address: patrycja.vaid@ahs.ca.
Patrycja
P
Vaid
Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada; Queensland University of Technology, Faculty of Health, School of Nursing, Kelvin Grove Campus, Brisbane, Australia.
Theresa
T
Green
Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada; Acute Pain Service, Alberta Health Services, Foothills Medical Centre, Calgary, Alberta, Canada.
Kelly
K
Shinkaruk
Faculty of Nursing, University of Calgary, Calgary, Alberta, Canada.
Kathryn
K
King-Shier
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000700:Analgesics / Q000008:administration & dosage*; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007649:Ketamine / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy* / Q000451:nursing; D012189:Retrospective Studies; D013123:Spinal Fusion; D016896:Treatment Outcome; D055815:Young Adult
D000700:Analgesics; D000701:Analgesics, Opioid; D007649:Ketamine