TIME-COURSE OF SUBJECTIVE PAIN RATINGS, AND WOUND AND LEG TENDERNESS AFTER HYSTERECTOMY

Background: Little information is available on time course of wound te nderness and relationship to subjective pain ratings following surgery . Furthermore, it is not clarified whether surgical procedures may ind uce hyperalgesia to mechanical stimulation outside the area of the sur gical incision. We have therefore assessed postoperative pain and pres sure pain thresholds (PPT) adjacent to and remote from the surgical in cision in 16 patients undergoing hysterectomy. Methods: Pressure pain threshold was assessed with pressure algometry preoperatively, 4 and 6 h and 1, 4 and 8 d after surgery on the abdominal wall 0.5, 5, 10 and 15 cm perpendicular to the wound, and on the anterior surface of the left thigh and tuberositas tibia. Furthermore, pain was assessed on a visual analogue scale (VAS) at rest and during cough. Results: PPT dec reased significantly 0.5, 5, 10 and 15 cm from skin incision up to 96 h after surgery (P<0.01) with a trend towards higher PPT with increasi ng distance from the wound. There was no significant changes in PPT on the thigh or the tuberositas tibia (P=0.49 and P=0.12) and no correla tion between changes in PPT near the wound and in remote areas (the le gs) (Rs=-0.082, P=0.44 and Rs=-0.0664, P=0.53, respectively). VAS at r est increased from 4 to 24 h and the cough values, remained elevated t hroughout the study (P<0.05). An inverse relationship was observed bet ween PPT 5 cm from the incision and VAS at rest (Rs=-0.406, P=0.0002) and during cough (Rs=-0.398, P=0.0002). Conclusion: These results indi cate that wound pressure algometry correlates to postoperative pain at rest and during movement and may be an alternative way of assessing w ound pain and tenderness. Increased tenderness to mechanical stimulati on remote from the surgical wound could not be demonstrated.