[Psychological prophylaxis training for coping with postoperative pain. Long-term effects]

Preoperative Anxiety and Postoperative Pain in Patients With Laparoscopic Hysterectomy

Objective: This study was designed to investigate preoperative anxiety situations and postoperative pain degree in Chinese patients undergoing laparoscopic hysterectomy and to analyze the related factors of preoperative anxiety and the correlation between preoperative anxiety and postoperative pain to provide a reference for effective postoperative analgesia management.

Methods: A total of 100 female patients undergoing laparoscopic hysterectomy were enrolled in this study and randomly divided into two groups (n = 50, each). In group A, the patients were treated with dexmedetomidine and sufentanil for postoperative analgesia. In group B, the patients were treated with sufentanil alone for postoperative analgesia. All patients were evaluated with a self-rating anxiety scale (SAS) 1 day before the operation. The patients’ pain was evaluated using the numerical rating scale (NRS) 1 day after the operation, and data were recorded.

Results: In these 100 patients, the highest preoperative SAS score was 48, and the average score was 40.99 ± 4.55 points, which is higher than the norm in China. There were significant differences in preoperative SAS scores among patients with different occupations and previous surgical experience (P < 0.05). There was no significant difference in SAS scores among patients with different education levels (P > 0.05). The postoperative NRS score of group A was significantly higher than that of group B, and the difference was statistically significant (P < 0.05). The correlation coefficients between SAS scores and NRS scores in groups A and B were 0.836 and 0.870, respectively, presenting with a significantly positive correlation.

Conclusion: Preoperative anxiety is an important predictor of postoperative pain. Patients undergoing laparoscopic hysterectomy have preoperative anxiety. The degree of anxiety is influenced by the occupation and previous operation experience of the patients, and patients with higher preoperative anxiety have greater postoperative pain. In addition, we should not neglect the management of postoperative pain because of the small trauma of laparoscopic surgery, and dexmedetomidine combined with sufentanil can improve the postoperative analgesic effect.

Prediction of persistent post-surgery pain by preoperative cold pain sensitivity: biomarker development with machine-learning-derived analysis

Background

To prevent persistent post-surgery pain, early identification of patients at high risk is a clinical need. Supervised machine-learning techniques were used to test how accurately the patients' performance in a preoperatively performed tonic cold pain test could predict persistent post-surgery pain.

Methods

We analysed 763 patients from a cohort of 900 women who were treated for breast cancer, of whom 61 patients had developed signs of persistent pain during three yr of follow-up. Preoperatively, all patients underwent a cold pain test (immersion of the hand into a water bath at 2-4 °C). The patients rated the pain intensity using a numerical ratings scale (NRS) from 0 to 10. Supervised machine-learning techniques were used to construct a classifier that could predict patients at risk of persistent pain.

Results

Whether or not a patient rated the pain intensity at NRS=10 within less than 45 s during the cold water immersion test provided a negative predictive value of 94.4% to assign a patient to the "persistent pain" group. If NRS=10 was never reached during the cold test, the predictive value for not developing persistent pain was almost 97%. However, a low negative predictive value of 10% implied a high false positive rate.

Conclusions

Results provide a robust exclusion of persistent pain in women with an accuracy of 94.4%. Moreover, results provide further support for the hypothesis that the endogenous pain inhibitory system may play an important role in the process of pain becoming persistent.

The psychology of chronic post-surgical pain: new frontiers in risk factor identification, prevention and management

In an era of considerable advances in anaesthesiology and pain medicine, chronic pain after major surgery continues to be problematic. This article briefly reviews the known psychological risk and protective factors associated with the development of chronic postsurgical pain (CPSP). We begin with a definition of CPSP and then explain what we mean by a risk/protective factor. Next, we summarize known psychological risk and protective factors for CPSP. Psychological interventions that target risk factors and may impact postsurgical pain are reviewed, including the acceptance and commitment therapy (ACT)-based approach to CPSP prevention and management we use in the Transitional Pain Service (TPS) at the Toronto General Hospital. Finally, we conclude with recommendations for research in risk factor identification and psychological interventions to prevent CPSP. Several pre-surgical psychological risk factors for CPSP have been consistently identified in recent years. These include negative affective constructs, such as anxiety symptoms, depressive symptoms, pain catastrophizing and general psychological distress. In contrast, relatively few studies have examined psychological protective factors for CPSP. Psychological interventions that target known psychological risk factors while enhancing protective psychological factors may reduce new incidence of CPSP. The primary goal of our ACT intervention is to teach patients a mindful way of responding to their postsurgical pain that empowers them to interrupt the negative cycle of pain, distress, behavioural avoidance and escalating opioid use that can limit functioning and quality of life while paradoxically amplifying pain over time. Early clinical outcome data suggest that patients who receive care from TPS physicians reduce their pain and opioid use, yet patients who also receive our ACT intervention have a larger decrease in daily opioid dose while reporting less pain interference and lower depression scores.