Strategies Aimed at Preventing Chronic Post-surgical Pain: Comprehensive Perioperative Pain Management after Total Joint Replacement Surgery

PURPOSE

Chronic post-surgical pain (CPSP) is a frequent outcome of musculoskeletal surgery. Physiotherapists often treat patients with pain before and after musculoskeletal surgery. The purposes of this paper are (1) to raise awareness of the nature, mechanisms, and significance of CPSP; and (2) to highlight the necessity for an inter-professional team to understand and address its complexity. Using total joint replacement surgeries as a model, we provide a review of pain mechanisms and pain management strategies.

SUMMARY OF KEY POINTS

By understanding the mechanisms by which pain alters the body's normal physiological responses to surgery, clinicians selectively target pain in post-surgical patients through the use of multi-modal management strategies. Clinicians should not assume that patients receiving multiple medications have a problem with pain. Rather, the modern-day approach is to manage pain using preventive strategies, with the aims of reducing the intensity of acute postoperative pain and minimizing the development of CPSP.

CONCLUSIONS

The roles of biological, surgical, psychosocial, and patient-related risk factors in the transition to pain chronicity require further investigation if we are to better understand their relationships with pain. Measuring pain intensity and analgesic use is not sufficient. Proper evaluation and management of risk factors for CPSP require inter-professional teams to characterize a patient's experience of postoperative pain and to examine pain arising during functional activities.

Emerging drugs for the treatment of postsurgical pain

INTRODUCTION

Postoperative pain is a distressful experience and remains to be a significant concern after surgery. Current agents either fail to prevent or minimize postoperative pain or cause a series of adverse effects, addiction, or abuse. Opioids have been the gold standard in the treatment of postoperative pain despite their well-described adverse effects. Many new agents with different mechanisms of action have been recently introduced to address this issue.

AREAS COVERED

This current review summarizes the list of new and emerging drugs investigated for their efficacy in controlling the postoperative pain and decreasing the need for rescue opioid use, adverse effect profile, abuse, and addiction potential.

EXPERT OPINION

Opioids have unrivaled analgesic efficacy. However adverse effects of opioids led to the search for better options. In mild pain most of the emerging drugs have been shown to control postoperative pain and decrease the use of rescue opioid, however fail to control pain after major surgeries causing severe pain. Specific agents such as Oliceridine, new local anesthetics, etc., are effective in controlling severe pain and hold a promise to replace opioids in the near future.

Gabapentinoids as a Part of Multi-modal Drug Regime for Pain Relief following Laproscopic Cholecystectomy: A Randomized Study

Background:

Gabapentinoids have been used as preemptive analgesics for pain management following laparoscopic cholecystectomy. Recently, multimodal analgesic techniques have been found superior to preemptive analgesia alone.

Aim:

The aim of this study is to evaluate and compare a single preoperative dose of pregabalin 150 mg and gabapentin 300 mg for pain relief following laparoscopic cholecystectomy as a part of multimodal drug regime.

Settings and Design:

This randomized, single-blind study was conducted after Ethical Committee approval and written informed consent from the patients.

Materials and Methods:

Fifty patients undergoing laparoscopic cholecystectomy under general anesthesia were randomly allocated to receive either 150 mg pregabalin (Group PG), or 300 mg gabapentin (Group GB) orally, 2 h before surgery. Standard anesthesia induction and maintenance were done. For intraoperative pain management, injection fentanyl 2 μg.kg^-1 intravenous (IV) along with injection voveran 75 mg IV and port site infiltration was used. Postoperatively, injection diclofenac 75 mg intramuscular TDS was continued. Severity of postoperative pain (visual analog scale [VAS]), postoperative fentanyl requirement and incidence, and severity of side effects were assessed. When VAS >40 mm or on patient's request, a Fentanyl bolus at an increment of 25–50 μg IV was given as rescue analgesia.

Results:

Intraoperative fentanyl requirement was 135 ± 14 μg in Group PG and 140 ± 14 μg in Group GB (P = 0.21). Postoperative, fentanyl requirement was 123 ± 18 μg in Group PG and 131 ± 23 μg in Group GB (P = 0.17) There was no statistically significant difference in the VAS score for static and dynamic pain. Time to the first requirement of analgesic was 5.4 ± 1.1 h in Group PG and 4.6 ± 1.6 h in Group GB (P = 0.015). No side effects were observed.

Conclusion:

We conclude that a single preoperative dose of pregabalin (150 mg) or gabapentin (300 mg) are equally efficacious in providing pain relief following laparoscopic cholecystectomy as a part of multimodal regime without any side effects.

Development and Internal Validation of the Postoperative Analgesic Intake Needs Score: A Predictive Model for Post-Operative Narcotic Requirement after Spine Surgery

STUDY DESIGN

Retrospective Cohort.

OBJECTIVE

The aim of this study was to develop a clinical tool to pre-operatively risk-stratify patients undergoing spine surgery based on their likelihood to have high postoperative analgesic requirements.

METHODS

A total of 1199 consecutive patients undergoing elective spine surgery over a 2-year period at a single center were included. Patients not requiring inpatient admission, those who received epidural analgesia, those who had two surgeries at separate sites under one anesthesia event, and those with a length of stay greater than 10 days were excluded. The remaining 860 patients were divided into a derivation and validation cohort. Pre-operative factors were collected by review of the electronic medical record. Total postoperative inpatient opioid intake requirements were converted into morphine milligram equivalents to standardize postoperative analgesic requirements.

RESULTS

The postoperative analgesic intake needs (PAIN) score was developed after the following predictor variables were identified: age, race, history of depression/anxiety, smoking status, active pre-operative benzodiazepine use and pre-operative opioid use, and surgical type. Patients were risk-stratified based on their score with the high-risk group being more likely to have high opioid consumption postoperatively compared to the moderate and low-risk groups in both the derivation and validation cohorts.

CONCLUSION

The PAIN Score is a pre-operative clinical tool for patients undergoing spine surgery to risk stratify them based on their likelihood for high analgesic requirements. The information can be used to individualize a multi-modal analgesic regimen rather than utilizing a "one-size fits all" approach.