Predicting Postoperative Pain: A Complex Interplay of Multiple Factors

Incidence and risk factors of pain following breast cancer surgery: a retrospective national inpatient sample database study

BACKGROUND

Postoperative pain (PP) is a dynamic process that reflects the complex interplay between symptoms, treatment, and patient experiences, and its intensity is reportedly primarily related to the severity of surgical trauma. However, no large-scale national database-based study has hitherto been conducted to assess the occurrence and features related to PP following breast cancer (BC) surgery.

METHODS

In this retrospective analysis, we screened BC surgery cases between 2015 and 2019 within the National Inpatient Sample (NIS) Database, utilizing the International Classification of Diseases (ICD) 10th edition clinical modification codes. The researchers identified patients who developed PP and compared them to those who did not. Factors associated with PP were then screened: patient demographics (age and race), hospital characteristics (type of insurance, bed size, teaching status, type of admission, location, and hospital area), length of stay (LOS), total cost during hospitalization, inpatient mortality, comorbidities, and perioperative complications. Data were analyzed using descriptive statistics. Multivariate logistic regression analysis was used to determine the independent risk factors for postoperative pain in BC surgery.

RESULTS

39,870 BC surgery cases were identified over a five-year period from 2015 to 2019. The overall occurrence of PP following breast cancer surgery was 6.15% (2,387 cases), with a slight upward trend every year. Significant racial disparities were observed, Whites associated with a higher incidence of PP (P < 0.001). In addition, the incidence of elective admission was 11.96% lower (67.491% vs. 79.451%) than that of patients without PP following breast cancer surgery (P < 0.001). Besides, PP was related to prolonged hospitalization duration (3 vs. 2 days; P < 0.001), and higher total cost ($68,283 vs. $60,036; P < 0.001). Multivariate logistic regression identified breast cancer surgery-independent risk factors for PP, including younger age, non-elective hospital admission, rural hospitals, depression, drug abuse, metastatic cancer, psychoses, weight loss, and chronic pulmonary disease. In addition, postoperative pain for BC was associated with urinary retention, gastrointestinal complications, continuous invasive ventilation, deep vein thrombosis, urinary tract infection, blood transfusion, arrhythmia, and chest pain.

CONCLUSION

Despite the low incidence of postoperative pain in BC surgery cases, it is essential to investigate factors predisposing to PP to allow optimal care management and improve the outcomes of this patient population.

Pain Neuroscience Education in elective surgery patients: study protocol for a randomised controlled trial

BACKGROUND

Pain Neuroscience Education (PNE) consists of an educational strategy that seeks to understand the biological processes of pain and how to control it. The main objective of this study will be to evaluate the impact of PNE on outcomes related to the postoperative period. The hypothesis is that the intervention may positively influence postoperative recovery, contributing to pain control, clinical indications, acceptance and consumption of analgesics and other pharmacological drugs that contribute to its control, as well as psychological aspects, such as anxiety, depression and pain catastrophising.

METHODS AND ANALYSIS

This will be an open, parallel, multicentre and randomised controlled clinical trial. A total of 100 participants aged between 18 and 59 years of age, of both genders, who are going to have elective general surgery will be evaluated. The intervention group will participate in a preoperative pain neuroscience educational session and also receive usual preoperative care, while the control group receives usual preoperative care as well. The educational session will last 30 min and consists of a video (5:20 min), a questionnaire about the content, time for participants to express their beliefs, thoughts and doubts. Participants will be evaluated preoperatively and there will be one postintervention evaluation. The intensity and characteristics of pain and anxiety are evaluated as primary outcomes. As secondary outcomes, pain catastrophising and depression are taken into account.

ETHICS AND DISSEMINATION

The project was approved by the Research Ethics Committee of the Faculty of Ceilandia, the Research Ethics Committee of the Institute of Strategic Health Management of the Federal District and the Research Council of the Hospital of Brasília-Rede Dasa (CAAE: 28572420.3.0000.8093). Recruitment began in June of 2023. All participants were included in the study only after their written consent. All data obtained will be analysed and distributed through publication in journals and at scientific events.

TRIAL REGISTRATION NUMBER

Brazilian Registry of Clinical Trials (ReBEC) (RBR-23mr7yy).

Development and prospective validation of postoperative pain prediction from preoperative EHR data using attention-based set embeddings

Preoperative knowledge of expected postoperative pain can help guide perioperative pain management and focus interventions on patients with the greatest risk of acute pain. However, current methods for predicting postoperative pain require patient and clinician input or laborious manual chart review and often do not achieve sufficient performance. We use routinely collected electronic health record data from a multicenter dataset of 234,274 adult non-cardiac surgical patients to develop a machine learning method which predicts maximum pain scores on the day of surgery and four subsequent days and validate this method in a prospective cohort. Our method, POPS, is fully automated and relies only on data available prior to surgery, allowing application in all patients scheduled for or considering surgery. Here we report that POPS achieves state-of-the-art performance and outperforms clinician predictions on all postoperative days when predicting maximum pain on the 0-10 NRS in prospective validation, though with degraded calibration. POPS is interpretable, identifying comorbidities that significantly contribute to postoperative pain based on patient-specific context, which can assist clinicians in mitigating cases of acute pain.

Analgesia for the Bayesian Brain: How Predictive Coding Offers Insights Into the Subjectivity of Pain

PURPOSE OF REVIEW

In order to better treat pain, we must understand its architecture and pathways. Many modulatory approaches of pain management strategies are only poorly understood. This review aims to provide a theoretical framework of pain perception and modulation in order to assist in clinical understanding and research of analgesia and anesthesia.

RECENT FINDINGS

Limitations of traditional models for pain have driven the application of new data analysis models. The Bayesian principle of predictive coding has found increasing application in neuroscientific research, providing a promising theoretical background for the principles of consciousness and perception. It can be applied to the subjective perception of pain. Pain perception can be viewed as a continuous hierarchical process of bottom-up sensory inputs colliding with top-down modulations and prior experiences, involving multiple cortical and subcortical hubs of the pain matrix. Predictive coding provides a mathematical model for this interplay.

The influence of preoperative anxiety on postoperative pain in patients undergoing cardiac surgery

Patients undergoing cardiac surgery represent a challenge in terms of pain management due to multiple factors relating to the patients and to the procedure itself. Our aim was to identify the influence of levels of preoperative anxiety on postoperative pain in patients undergoing cardiac surgery and explore associations between preoperative anxiety, postoperative pain, analgesic requirements, and sex. We present a prospective cohort study of 116 patients undergoing cardiac surgery between January and April 2020. Preoperative anxiety was evaluated using the State-Trait Anxiety Inventory and the amount of morphine needed to keep pain intensity below 4 on the verbal numerical rating scale was recorded for 48 h post-surgery. Given the extracorporeal circulation time, type of surgery and body surface, it was observed that every percentile increase in preoperative state anxiety led to an extra 0.068 mg of morphine being administered. For each extra year of age, the amount of morphine needed decreased by 0.26 mg, no difference was observed between men and women in terms of preoperative anxiety or postoperative analgesics requirements. It may be concluded that in cardiac surgery, postoperative analgesic requirements increased with higher levels of preoperative state anxiety and decreased for every extra year of age.

Clinical Update on Patient-Controlled Analgesia for Acute Postoperative Pain

Patient-controlled analgesia (PCA) is an effective method for controlling acute pain, including postoperative pain in adults and in children from five years of age, pain resulting from labor, trauma, or other medical situations, or chronic and malignant pain. The treatment consists of a mini-computer-controlled infusion pump permitting the administration of on-demand, continuous, or combined doses of analgesic (mainly opioid) variations in response to therapy, which allows pain to be significantly controlled. Intravenous (IV)-PCA minimizes individual pharmacodynamics and pharmacokinetic differences and is widely accepted as a reference method for mild or severe postoperative pain. IV-PCA is the most studied route of PCA; other delivery methods have been extensively reported in the literature. In addition, IV-PCA usually voids the gap between pain sensation and analgesic administration, permitting better recovery and fewer side effects. The most commonly observed complications are nausea and vomiting, pruritus, respiratory depression, sedation, confusion and urinary retention. However, human factors such as pharmacy preparation and device programming can also be involved in the occurrence of these complications, while device failure is much less of an issue.

A systematic review and meta-analysis of efficacy of ultrasound-guided single-shot quadratus lumborum block for postoperative analgesia in adults following total hip arthroplasty

STUDY OBJECTIVE

To evaluate the efficacy of ultrasound-guided single-shot quadratus lumborum block (QLB) for postoperative analgesia in adults following total hip arthroplasty (THA).

DESIGN

Systematic review and meta-analysis.

SETTING

Perioperative period.

PATIENTS

Adult patients undergoing THA.

METHODS

Studies were identified by performing electronic searches in the following electronic databases, PubMed (Medline), Cochrane Central Registry of Trials (CENTRAL), and Google Scholar. We sought studies in adult patients undergoing THA, comparing QLB with a control group (no block, sham block or any other ultrasound guided regional nerve blocks). A total of 774 patients from 10 studies (7 randomized controlled, one controlled clinical and two retrospective study) were included in this meta-analysis.

MAIN RESULTS

The 24 hr opioid consumption was similar in both the groups [WMD -4.09; 95%CI (-9.00, 0.83); P = 0.10; I2 = 95%]. The pain scores at rest at 24 hr was significantly less in QLB group [WMD -0.62; 95% CI (-1.15, -0.10); P = 0.02; I2 = 75%].The difference in pain scores was not clinically significant. The pain scores on movement at 24 hours, time to first analgesic request and time to discharge from hospital were similar in both the groups.

CONCLUSIONS

QLB as part of multimodal analgesia did not result in any significant analgesic benefits in patients undergoing hip arthroplasty in terms of either postoperative opioid consumption or pain scores at rest and on movement. Overall, the level of certainty is low. Further, well-designed trials are required to verify the results.

PROSPERO REGISTRATION NO

CRD42021253425.