Optimal Postoperative Analgesia for the Opiate-Naïve Patient

INTRODUCTION

The management of postsurgical pain has evolved significantly throughout the years. Since the discovery of morphine in the early 1800s, the field has relied heavily on opioid-based medications. Bayer’s aspirin, which was in widespread use by 1899, provided one of the first alternatives to opioids for the treatment of mild to moderate pain. In 1921, the modern technique for lumbar epidural anesthesia for upper abdominal surgeries was developed and popularized by Spanish surgeon Fidel Pages. The field further expanded after the Second World War with the embrace of evidence-based practices and numerical scales to quantify patient-reported pain intensity. In 1965, “gate control theory” was introduced, offering an explanation for how nonpainful stimuli could override painful sensations, thus laying the groundwork for a multidisciplinary approach to pain management.

Acknowledging that the treatment of acute pain requires specialized expertise, Ready and colleagues introduced the concept of a formalized acute pain service in 1988. Soon after, investigators began to focus on developing evidence-based practice guidelines for postsurgical and acute pain management. Early attempts focused on single-modality approaches. In 1993, Kehlet and Dahl revolutionized the field by promoting the concept of “balanced analgesia,” bringing multimodal approaches to the forefront of postoperative pain management and advocating for procedure-specific pain treatments. This opened the door to our current milieu of nonopioid analgesics, including nonsteroidal antiinflammatory drugs (NSAIDs), acetaminophen, local anesthetics, alpha-2 agonists, N-methyl-D-aspartate (NMDA) antagonists, steroids, and gabapentinoids.

Our modern approach to postsurgical pain control is incorporated into broader enhanced recovery after surgery (ERAS) protocols. These ERAS pathways have been instituted broadly in the United States for a variety of surgical procedures and encourage effective management of postoperative pain, minimization of opioid consumption, and preservation of overall physical function. Regional techniques offer an attractive means of accomplishing these goals. Furthermore, evidence has emerged for the opioid-sparing properties of adjuvants such as lidocaine and ketamine. Considering the risk for respiratory depression, excessive sedation, physical dependence, and other short- and long-term adverse effects associated with opioid use, it remains to be seen what role opioids should play in the future, particularly in the opiate-naïve patient.

OPTIONS

Although our treatment options for control of postoperative pain in the opioid-naïve patient have greatly expanded, there remain significant variation in practice and barriers to care. Studies have looked at the effects of race, geographic region, and insurance status on anesthetic care. Tighe and colleagues reviewed 6000 orthopedic surgery cases and found the likelihood of receiving a nerve block depended on the type of facility at which the procedure was performed. Specifically, a nerve block was more likely to be performed in metropolitan service areas (odds ratio [OR] 1.86, 95% confidence interval [CI] 1.19–2.91, p = .007) or freestanding surgical facilities (OR 2.27, 95% CI 1.74–2.96, p < .0001). The study also found that patients were more likely to receive a peripheral nerve block if government programs (OR 2.5, 95% CI 1.01–6.21, p = .048) or private insurance (OR 2.62, 95% CI 1.12–6.13, p = .03) were used to support payment as opposed to self-pay or charity care. It remains unclear how large an impact these barriers to anesthetic care have on overall patient outcomes.

It is important that we address these discrepancies in anesthetic care. A better understanding of the modalities available may help providers in caring for patients in the postoperative setting. In this chapter, we will review proven strategies for treating postoperative pain in the opiate-naïve patient. We will review the evidence for the use of epidural analgesia, NSAIDs, continuous peripheral nerve blocks (CPNB), lidocaine, and opioids. The chapter will also focus on areas of uncertainty in the field and provide evidence-based guidelines based on the information presented.

EVIDENCE