A new version of the ischemic tourniquet pain test.

A new method of producing ischemic tourniquet pain is presented. The present test model showed a sex difference in the pain recordings. Sum pain intensity (SPI) for a 5 min trial period of ischemic pain was lower for males than for females (p less than 0.0001). The observed variability between male test subjects was greater than between female subjects, while the variation in pain scores within subjects was lower for males compared to females. The differences between sexes as a group with respect to variability of pain recordings were not statistically significant. Due to the observed sex differences in pain recording it is recommended to use test subjects of the same sex when restricting the test procedure to a limited number of subjects. The present version of the tourniquet pain test, used according to the recommended criteria, allows discriminating between i.v. administered placebo, opioid analgesics (pethidine) and ketamine.