Preoperative Psychologic and Demographic Predictors of Pain Perception and Tramadol Consumption Using Intravenous Patient-controlled Analgesia

Postoperative pain is characterized by a wide variability of patients' pain perception and analgesic requirement. The study investigated the extent to which demographic and psychologic variables may influence postoperative pain intensity and tramadol consumption using patient-controlled analgesia (PCA) after cholecystectomy.Eighty patients, aged 18 to 70 years, with an American Society of Anesthesiologists physical status I or II and a body mass index between 18.5 and 24.9, undergoing laparoscopic cholecystectomy were enrolled. Self-rating anxiety scale (SAS) and self-rating questionnaire for depression (SRQ-D) were used--1 day before surgery--to assess patients' psychologic status. General anesthesia was standardized. PCA pump with intravenous tramadol was used for a 24-hour postoperative analgesia. Visual analog scale at rest (VASr) and after coughing (VASi) and tramadol consumption were registered. Pearson's and point biserial correlations, analysis of variance, and step-wise regression were used for statistical analysis.Pearson r showed positive correlations between anxiety, depression, and pain indicators (P0.05). Moreover, female patients had higher pain indicators (P0.05). Analysis of variance showed that anxious (P0.05) and depressed (P0.001) patients had higher pain indicators, which significantly decreased during the postoperative 24 hours (P0.00001). Regression analysis revealed that tramadol consumption was predicted by preoperative depression (P0.001). VASr was predicted by sex and SRQ-D (P0.05). VASi was predicted by sex and SAS (P0.05).Pain perception intensity was primarily predicted by sex with an additional role of depression and anxiety in determining VASr and VASi, respectively. Patients with high depression levels required a larger amount of tramadol.