FM patients who seem resistant to the more routine therapies have a new pain relief treatment available, according to a study presented at the ANESTHESIOLOGY™ 2013 annual meeting. Intravenous (IV) lidocaine infusion provided significant pain relief to patients, although the pain relief was much less for African-Americans and smokers.
Statistics were collected for sex, race, body weight, pain duration, pain relief duration after lidocaine infusion, and scores on the brief pain inventory scale, visual analog scale and pain interference scale before and after the infusion.
The study found an almost 10 per cent average decrease in the brief pain inventory scale score, which dropped from 83.18 before the infusion to 73.68 after the infusion. The average pain interference score dropped from 7.73 to 6.88. The brief pain inventory score was much lower for non-smokers than for smokers; non-smokers’ average score was 72.63, while smokers’ average score was 89.98.
Dr Huh, M.D., Ph.D., professor and medical director of the Department of Pain Medicine at The University of Texas MD Anderson Cancer Center, Houston, and adjunct professor of the Department of Anesthesiology at Duke University Medical Center, Durham, N.C., hypothesized that because smokers frequently have vascular damage that impairs blood circulation, the lidocaine may not reach the painful area because of poor blood flow. He also suggested that the benefit of lidocaine may be reduced because smokers have significant amounts of toxic chemicals in their blood.
The difference in pain interference scores for white patients and African-American patients was .028. For this test, a score less than .05 is considered statistically significant. Dr. Huh could not be certain about the reason for the difference, but noted, “Many drugs are more effective or less effective for certain ethnic groups. For example, some blood pressure medications are more effective for certain races. I think this finding is quite possibly related to genetic makeup.”
Further, I found no material stating how often or for how long this type of infusion would be required.