A bilateral clinical model for the study of acute and chronic pain after breast-reduction surgery

Background: There is a need for new clinical models to investigate effectiv ely the development of pain after surgery and the effect, if any, of pre-em ptive treatment. Bilateral models are of special interest, since the patien t serves as his/her own control. The objective of this preliminary study wa s to test a clinical model for the study of acute and chronic pain after bi lateral reduction mammoplasty. Methods: Eight patients participated in the study where the breasts were ra ndomized to test and control groups. In each patient, one breast was preope ratively infiltrated with lidocaine and adrenaline and the other breast inf iltrated with saline and adrenaline. Assessment included visual analogue sc ale (VAS) pain intensity, thermal thresholds, mapping for punctate hyperalg esia and tactile sensation. Assessments were made preoperatively, postopera tively and at 6 months after surgery. Results: With regard to acute postoperative pain intensity, the model demon strated a clear difference between lidocaine and placebo treated breasts. T here was no difference between lidocaine and placebo treated breasts with r egard to chronic pain, but these results are inconclusive due to small numb er of patients. Conclusion: The model is sensitive and may be useful in studies of mechanis ms of development and prevention of chronic pain after surgery.