Pre-operative Pregabalin and Ketamine to Prevent Phantom Pain

About This Study

Phantom limb pain (PLP) is as painful sensations located to the missing limb and classified as neuropathic pain. In the United States, an estimated 1.7 million patients have undergone limb amputation, and 60% to 80% of these patients develop PLP (1-2) and it is usually resistant to a wide variety of treatments (1-4). Three factors may contribute to the development of persistent, post-amputation PLP by inducing central sensitization at different times relative to surgery: pre-amputation pain, noxious intraoperative stimuli, and acute postoperative pain (5-7). Investigators hypothesis that pre-amputation period could be important in eliminating Phantom Limb Pain (PLP) in the patients in whom cortical reorganization is not yet established. The reduction of pre-operative pain and prevention of formation of pain memories may eliminate development of PLP by using dual networks treatment strategy. This Phase III, randomized, double-blind, placebo-controlled study is designed to evaluate the efficacy of pre-operative pregabalin (lyrica) and ketamine in eliminating phantom limb pain in patients undergoing lower limb amputation.

Conditions Studied

Interventions

• •Pregabalin
• •Ketamine
• •Placebo

Eligibility

Inclusion Criteria:

1. Ager 18-65 years old
2. Unilateral lower-limb amputations
3. Able to understand study procedures
4. If on opioids, patient should be on a stable dose for at least one week prior to enrolment.
5. Subject with normal renal function (CrCI \> 60 mL/min).

Exclusion Criteria:

1. Cases with only digits amputation
2. Current or recent history of alcohol and drug abuse
3. Concomitant use of CYP 3A4 medications
4. Unstable hypertension
5. Abnormal EKG
6. Increased intracranial pressure currently or in the past six months
7. Increased intraocular pressure currently or in the past six months
8. Liver disease or AST/ALT ≥ 3 ULN or total bilirubin \>2 x ULN
9. Poorly controlled psychiatric illness.
10. A history of seizure
11. Using other anticonvulsant drug
12. Renal impairment as determined by clinically significant labs
13. Women of childbearing age who either has:

    1. A positive pregnancy test
    2. Unprotected heterosexual sex since their previous menses or;
    3. Not currently using and/or willing to use a medically approved form of contraception (e.g., birth control pill)

Study Locations (2)