Double Blind Placebo Controlled Study of Outpatient Intravenous Ketamine for the Treatment of CRPS
Complex Regional Pain Syndrome
About this trial
This is an interventional treatment trial for Complex Regional Pain Syndrome
Eligibility Criteria
Inclusion Criteria:
- Patients diagnosed with CRPS based on the modified IASP (International Association for the Study of Pain) research criteria (Harden RN and Bruehl SP
- Diagnostic Criteria: The Statistical Derivation of the Four Criterion Factors.
In CRPS: Current Diagnosis and Therapy, Progress in Pain Research and Management, Vol 32: pp 45-58, 2005), whose condition is intractable for at least six months and have failed at least three of the following therapies:
- Nerve blocks
- Opioid analgesics
- Non-opioid analgesics
- Non-steroidal anti-inflammatory drugs
- Anti-seizure medications
- Antidepressants
- Muscle relaxants; or
- Physical therapy.
- The patients must be ketamine naïve and can be of either gender including all racial and minority groups. The patient's age must be between 18 and 65 years, inclusive.
- The study subjects must report pain levels equal to or greater than 4 on a scale of 0-10 (0 = no pain and 10 = unbearable pain). The pain must be stable over time and not vary more that 1 pain level.
- The patient must be on a stable dose of CRPS medications for 28 days prior to and throughout the duration of the study.
- The patient must be accompanied by a responsible adult.
- The patient will be instructed that he/she will not be allowed to drive home following the infusion. Therefore in order to be included in the study the subjects must arrange for transportation for the 10 day duration of the study.
Exclusion Criteria:
- Patients less than 18 years of age will be excluded. In this initial study, patients over 65 years of age will be excluded due to possible unforeseen concomitant medical problem.
- Patients that have previously undergone intravenous ketamine infusions will be excluded from the study.
- Patients who are pregnant, are lactating, have known psychotic or psychiatric illness, are afflicted with glaucoma or have thyrotoxicosis will also be excluded.
- Any patient that is unable to provide consent due to cognitive difficulties will not be used in this study.
- Patients that can not provide the means to be transported home following daily infusions will be excluded from the study.
- The investigators feel that issues concerning monetary gain and or loss due to the patient's medical condition may adversely affect the study, therefore, patients with active litigation, compensation or disability issues related to their CRPS will be excluded.
- Patients with a history of substance abuse will be excluded.
- Patients on certain blood pressure lowering medications such as calcium blockers, or beta blockers will be excluded from the study.
- Patients with major medical problems including but not limited to; uncontrolled hypertension, hypotension, cardiac failure, renal failure or liver failure will not be used in this study.
Sites / Locations
- Drexel University College of Medicine Department of Neurology
Arms of the Study
Arm 1
Arm 2
Placebo Comparator
Experimental
1
2
INFUSION PLAN: All patients will be infused intravenously with 100 ml of normal saline with or without ketamine for four hours (25 ml/hr) daily for 10 days. The maximum intravenous ketamine infusion dose for this study will be 0.35 mg/kg/hr, not to exceed 25 mg/hr (100 mg of ketamine over a 4 hour period). On the first day, the intravenous ketamine infusion will be set to 50% of the maximum rate. On the second day, the intravenous ketamine infusion will be increased to 75% of the maximum rate. On the third day, the intravenous ketamine infusion will be increased to the maximum rate. The daily ketamine infusion rate is maintained at this level for the duration of the ten day study.