ASSESSMENT OF PAIN THRESHOLD AND PAIN TOLERANCE IN WOMEN IN LABOR ANDIN THE EARLY POSTPARTUM PERIOD BY PRESSURE ALGOMETRY

The changes in the pressure pain threshold (PPThr) and pressure pain t olerance (PPTol) in 41 parturients have been studied during the active phase of labour and in the early post-partum period. The sensitivity to pressure stimuli was examined with an electronic pressure algometer placed on the sternum during the interval between painful contraction s, after extradural analgesia and 24 h after childbirth. Prior to extr adural analgesia, mean (+/-SD), PPThr and PPTol were 4.9+/-1.6 kg 0.25 cm(-2) and 6.9 +/- 1.8 kg 0.25 cm(-2), respectively. Similar values w ere recorded Ih after induction of the extradural block when the pain of labour was abolished. At 24 h post-delivery, a significant decrease in both PPThr and PPTol was noted (P<0.001). The lack of influence of extradural analgesia on pressure algometry values, and the elevated s ensitivity to pain in the early post-partum period, may be related to the influence of pregnancy and labour on the appreciation of pain.