[Predicting of postoperative pain level and morphine consumption by preoperative pressure pain assessment in patients before elective surgery].

The aim of this study was to predict a postoperative pain severity and morphine consumption by preoperative pressure pain assessment.321 patients scheduled for elective surgery (lumbar discectomy, lumbar spinal fusion, hysterectomy, thoracotomy and total hip replacement) in 2009-2013 were enrolled in retrospective study. Pre-operatively, the pain threshold (PTH) and tolerance (PT) in Newton (N) were measured using the pressure algometry. Post-operatively, the pain scores at rest and during movement at 1st postoperative day (POD) using 10 cm VAS were also recorded Patients could get morphine by PCA device in addition to nonopioid analgesia post-operatively.PTH and PT were respectively 34 (24; 45.6) and 74 (54; 95) N, VAS at 1 POD 2 (1; 3.75) at rest and 4 (2,5; 6.25) cm during movement. Pre-operative PT correlated significantly with pain score during movement in patients at 1 POD (R = -0.124, p = 0.026, n = 320). Logit regression analysis found that pain control adequacy during movement at 1 POD could be predicted with PT (β = 0.011, Std. Err = 0.004, χ2 = 8.536, p = 0.004, OR = 1.011, 95% CI = 1.004-1.018). Morphine consumption by PCA device in patients was 21.25 (7.5; 38) mg. We found a significant correlation between pre-operative PT and post-operative morphine consumption (R = -0.306, p = 0.0006, n = 122).Post-operative pain severity during movement at 1st postoperative day can be predicted with the pre-operative pain tolerance using the pressure algometry. There is significant moderate negative correlation between pre- operative pain tolerance and post-operative morphine consumption by PCA device in patients at 1st postoperative day.