Multimodal Pain Control, Enhanced Recovery After Surgery, and Rapid Recovery Protocols for the Direct Anterior Approach

Adam E. Roy

Antonia F. Chen

Vivek M. Shah

Key Learning Points

Satisfactory pain control is essential to the success of enhanced recovery after surgery (ERAS) treatment protocols
Multimodal pain control protocols span the preoperative, intraoperative, and postoperative phases of surgical care
A multidisciplinary team approach is essential to the success of multimodal pain control protocols
Common techniques include the use of neuraxial anesthesia, local infiltration analgesia (LIA), peripheral nerve blocks, and nonopioid and opioid pain medications
Multimodal pain control protocols avoid the adverse effects known to slow the recovery process and improve patient satisfaction

Introduction

Our current health care landscape is rapidly changing, with a trend toward bundled payment programs that engage and motivate surgeons to control the episode of care. For many orthopaedic surgeons, this is undoubtedly a new and daunting prospect. However, ownership of the patient care episode provides the opportunity for positive growth and improvement in care, all while reducing health care costs.¹^,²

In the bundled payment environment, a successful outpatient arthroplasty program is a key to success by means of cost savings. Notably, the Centers for Medicare and Medicaid Services removed both total knee arthroplasty (TKA) and total hip arthroplasty (THA) from the Inpatient Only List, on January 1, 2018, and January 1, 2020, respectively.³ In addition, models continue to predict a rise in total joint arthroplasty (TJA), with expected THA and TKA growth of 71% to 171% and 85% to 189%, respectively, by the year 2030.⁴^,⁵ There will be an abundance of hip and knee arthroplasty candidates in the future; to achieve success in this new health care landscape, surgeons must select patients appropriately and develop standardized treatment protocols for outpatient surgery.

The ERAS concept involves identifying barriers to postoperative recovery and subsequently using evidence-based treatment protocols to standardize the preoperative, intraoperative, and postoperative phases of surgical care.⁶ ERAS protocols have been shown to reduce complications, accelerate recovery, and improve patient outcomes, all while simultaneously reducing costs.⁷^,⁸ Satisfactory pain control is one essential component to the overall success of standardized ERAS treatment protocols. Multimodal pain control protocols, specifically, span all three phases of surgical care and facilitate rapid recovery after TJA.⁹ In this chapter, we discuss general principles of rapid recovery protocols with a focus on multimodal pain control. We explore in detail the common pain control strategies and medications available within each phase of surgical care.

Multimodal Pain Control

Satisfactory pain control is an essential part of rapid recovery after hip and knee arthroplasty. Multimodal pain control emerged in an effort to avoid the adverse effects associated with general anesthesia and opioid analgesia, including postoperative nausea and vomiting, hypotension, respiratory depression, and ileus.⁹^,¹⁰ When considering outpatient arthroplasty, including direct anterior approach (DHA) THA, avoiding these complications while simultaneously improving patient satisfaction is paramount to success.

Multimodal pain control necessitates the use of varying anesthetic techniques and nonopioid pain medications implemented or administered at varying times during the three phases of surgical care. The ultimate goal is to minimize the use and associated adverse effects of traditional anesthetics and treatment options, such as sedation, nausea and vomiting, respiratory depression, and ileus.⁹ Multimodal pain control protocols are complex, and, as a result, require a multidisciplinary team approach. The surgery, anesthesia, physical therapy, and nursing teams must work closely together because each team possesses unique skills vital to successful protocol implementation. Techniques commonly used include neuraxial anesthesia, LIA, and peripheral nerve blocks (PNBs).⁹^,¹⁰ Nonopioid pain medications commonly used include nonsteroidal anti-inflammatory drugs (NSAIDs), acetaminophen, gabapentinoids, and glucocorticoids. When used in combination, these varying techniques and medications produce excellent results. The multimodal pain control protocol in use at our institution is provided in Table 42.1.

TABLE 42.1 Multimodal Pain Control Protocol for Direct Anterior Approach Total Hip Arthroplasty in Use at Our Institution

Preoperative phase
Celecoxib 200 mg once Meloxicam 15 mg once Naproxen 500 mg once	Patients prescribed one of three medications listed
Acetaminophen 975 mg once
Gabapentin 300 mg once
Intraoperative phase
Spinal anesthesia	4 mL 0.5% ropivacaine
Local infiltration analgesia	100 mL solution 50 mL 0.5% ropivacaine 30 mg ketorolac 0.5 mg epinephrine 80 μg clonidine
Postoperative phase
Celecoxib 200 mg once daily PRN Meloxicam 7.5 mg once daily PRN Ibuprofen 600 mg 3 times daily PRN Naproxen 450 mg twice daily PRN	Patients prescribed one of four medications listed
Acetaminophen 975 mg every 6 h PRN
Gabapentin 300 mg	Every 8 h for 1 wk followed by once nightly for 1 mo
Dexamethasone 10 mg daily for at least 1-2 d
Tramadol 50-100 mg every 6 h PRN	Pain 4-7 of 10 on VAS
Dilaudid 1-2 mg every 4 h PRN	Pain 8-10 of 10 on VAS
PRN, as needed; VAS, visual analog scale.

Preoperative Phase

The preoperative phase of surgical care begins with careful patient selection for outpatient surgery. Relative exclusion criteria should be adhered to and should include medical conditions associated with increased hospital length of stay (LOS). Berend et al¹¹ conducted a retrospective review of 1472 outpatient THAs to assess preoperative medical conditions and postoperative overnight hospital stay and complications. Analysis did not reveal an association between optimized preoperative medical conditions and complications; however, the presence of at least one medical condition was associated with an increased risk in overnight hospital stay. Relative exclusion criteria for the study by Berend et al¹¹ included medical conditions that cannot be optimized, including congestive heart failure or valvular disease, chronic obstructive pulmonary disease or home oxygen use, untreated obstructive sleep apnea and body mass index greater than 40 kg/m², hemodialysis or elevated serum creatinine, cerebrovascular accident, and solid organ transplant.⁶^,¹¹ Additionally, patients selected for surgery must work with providers to optimize medical conditions that may inhibit positive operative results. Standardized patient education is recommended because preoperative education has been shown to decrease patient stress and anxiety and increase patient confidence and satisfaction.⁶

In addition, ERAS protocols are moving away from the traditional prolonged preoperative fast because of the resultant dehydration and stress response shown to cause postoperative insulin resistance.⁶ Preoperative oral carbohydrate loading has been assessed in patients undergoing THA, revealing decreases in postoperative insulin sensitivity, nausea, and pain.¹² At our institution, patients are instructed to consume 2 L electrolyte fluid (reduced sugar alternative for diabetics) before midnight of the surgical date. Additionally, patients who are not the first surgical case of the day are given the option to consume 600 mL electrolyte fluid up to 3 hours before the scheduled surgical start time.

In the preoperative phase of surgical care, a number of medications are typically administered in order to “get ahead and stay ahead” of the subsequent pain that results from the surgical incision and tissue handling.¹²^,¹³ The strategy to “get ahead and stay ahead” was born out of the transition from the “sick patient model of care” to our current “well-patient model of care” in which the patient is medically optimized for surgery.¹³ In addition to executing the surgical plan, the primary goal in this model is to “get ahead and stay ahead” of complications that can deter rapid recovery. Inadequate pain control is one such complication, as are excessive volume depletion, including blood loss, and nausea and vomiting.¹³

Preemptive analgesia is a philosophy that embodies the get ahead and stay ahead strategy as it relates to pain control.⁹^,¹⁰^,¹²^,¹³^,¹⁴ Moreover, preemptive analgesia is key to the successful multimodal pain control protocol. In essence, preemptive analgesia involves administering medications before the initiation of noxious stimuli inherent to surgery. Preemptive administration decreases the production of inflammatory chemicals and the subsequent peripheral and central nervous system sensitization.⁹^,¹⁰ Additionally, excessive nociceptive afferent input to neurons of the spinal cord and brain results in central nervous system sensitization.¹⁵ The decrease in nerve fiber sensitization effectively increases the pain threshold, which results in less postoperative pain and a decreased risk of developing chronic neuropathic pain.⁹^,¹⁰^,¹⁵

The effectiveness of preemptive analgesia in reducing postoperative pain has been assessed in the literature. In their meta-analysis of 66 randomized controlled trials (RCTs) including 3261 patients, Ong et al¹⁶ assessed three outcome variables after the administration of varying preemptive pain control modalities: postoperative pain scores, cumulative analgesic requirements, and interval to rescue analgesic. Epidural analgesia improved all three outcome variables, whereas NSAIDs and LIA improved cumulative analgesic requirement and interval to rescue analgesic. Notably, systemic opioid administration was found to be the least efficacious of all modalities assessed.¹⁴^,¹⁶

For preemptive analgesia to be effective, the selected medications must be simple to administer and fast acting without the adverse effects associated with traditional medications.¹⁰^,¹⁷ Medications found to possess these characteristics include NSAIDs, acetaminophen, gabapentinoids, and glucocorticoids. Table 42.2 provides the mechanism of action of these preemptive analgesic medications. These medications may be initiated days before surgery but more typically are administered 1 to 2 hours before surgery in a designated preoperative area.⁹^,¹⁰ We discuss these medications in further detail later, including how they are implemented in the multimodal pain control protocol at our institution.

TABLE 42.2 Mechanism of Action (MOA) of Common Preemptive Analgesic Medications

Medication	MOA
Nonsteroidal anti-inflammatory drugs	Reduce prostaglandin production through the inhibition of cyclooxygenase enzymes
Acetaminophen	Poorly understood; likely multifactorial through the effects on prostaglandin, serotonin, opioid, and cannabinoid pathways
Gabapentinoids	Reduce neuronal excitability through the inhibition of voltage-gated calcium channels
Dexamethasone	Reduce production and release of inflammatory molecules through the inhibition of peripheral phospholipase enzyme

Nonsteroidal Anti-Inflammatory Drugs

Prostaglandins are potent molecules involved in a multitude of biologic processes, including inflammation and pain, and are produced through multiple enzymatic processes.¹⁸^,¹⁹ First, the enzyme phospholipase A₂ releases arachidonic acid from phospholipids, a key component of cell membranes. Next, the enzyme cyclooxygenase (COX) converts arachidonic acid to prostaglandin H₂, a key prostaglandin precursor.¹⁸ The interaction of prostaglandins with ion channels in the peripheral and central nervous system results in sensitization, which decreases the pain threshold and creates a hypersensitivity to stimuli.¹⁸

NSAIDs act peripherally by blocking COX enzymes, which reduces prostaglandin production, resulting in decreased inflammation and pain. There are two known COX enzymes, cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), and traditional, nonselective NSAIDs act on both. COX-1 enzymes are found in most cells, including platelets and cells of the gastric mucosa and kidney. COX-2 enzymes are also found in kidney cells, in addition to brain cells and cells at sites of inflammation.¹⁹ The major adverse effects associated with traditional NSAIDs include renal dysfunction, platelet dysfunction, and gastrointestinal (GI) toxicity. Risk factors for GI complications include high NSAID dose, age greater than 60 years, concurrent use of anticoagulants and glucocorticoids, and a history of GI bleeds.¹⁹ Fortunately, NSAIDs have been developed, such as celecoxib, which selectively inhibit the COX-2 enzyme. COX-2 inhibitors avoid the platelet dysfunction and GI toxicity effects while maintaining anti-inflammatory and pain control properties. Notably, COX-2 inhibitors have been linked to adverse cardiovascular events; however, celecoxib has not been shown to increase risk at doses less than 400 mg/d.⁹^,¹⁰^,²⁰ Nonetheless, the use of selective COX-2 inhibitors in patients with cardiovascular and/or renal risk factors should be carefully considered.

The role of NSAIDs in TKA pain management has been studied extensively with positive results. For instance, Meunier et al²¹ conducted a randomized placebo-controlled trial in which 50 patients awaiting TKA were randomized into one of two treatment arms, placebo or celecoxib. Patients were instructed to take either placebo or celecoxib 200 mg 1 hour preoperatively followed by twice-daily dosing for 3 weeks postoperatively. Analysis revealed decreased morphine use and a 30% decrease in pain scores in the celecoxib group at 4 weeks postoperatively, without a difference in blood loss between groups. At 1 year postoperatively, there were no differences in pain scores.²¹ Furthermore, Lin et al²² conducted a systematic review and meta-analysis of all RCTs to assess the effects of COX-2 inhibitors in TKA, which also revealed positive results. Eight RCTs including 571 patients undergoing TKA were assessed. Analysis revealed decreased pain scores, opioid use, and adverse effects contributable to opioid use, as well as increased range of motion in the COX-2 inhibitor group at 3 days postoperatively.²²

Acetaminophen

Acetaminophen, also known as paracetamol and N-acetyl-para-aminophenol, is an effective analgesic and antipyretic. Furthermore, acetaminophen has a favorable adverse-effect profile and works synergistically with other medications, making it an ideal medication in multimodal pain control protocols. Interestingly, acetaminophen was first used medically in 1887 but the exact mechanism of action is still unknown.²³^,²⁴ Experts believe the primary analgesic effects are the result of action on the central nervous system, likely involving prostaglandin, serotonin, opioid, and cannabinoid pathways.²⁴

As mentioned previously, acetaminophen is an ideal medication in multimodal pain control protocols. It can be administered both orally and intravenously and can be
effective in all three phases of surgical care. The efficacy of oral and intravenous (IV) acetaminophen was assessed by Sun et al²⁵ in their systematic review and meta-analysis. Two RCTs including 236 patients undergoing TJA were assessed. Analysis revealed no difference in postoperative pain scores or opioid consumption at 12, 24, and 48 hours between the oral and IV groups.²⁵ There is no ideal timing for administering acetaminophen in the perioperative period.

Gabapentinoids

Gabapentin and pregabalin are gabapentinoid class medications commonly used in multimodal pain control protocols. Gabapentinoids act primarily through the inhibition of voltage-gated calcium channels, which reduces neuronal excitability.¹⁰^,²⁶^,²⁷ Gabapentin and pregabalin share a similar structure and mechanism of action; however, pregabalin is more potent. As a consequence of this higher potency, adverse effects such as sedation and dizziness may occur more commonly with pregabalin use, especially in elderly patients.¹⁰^,²⁶

The use of gabapentinoids for the treatment of neuropathic pain is widely accepted and supported in the literature.²⁸ In contrast, the use of gabapentinoids for the treatment of acute pain is currently off-label because multiple efficacy studies have revealed mixed results.²⁶ Buvanendran et al²⁹ conducted a randomized placebo-controlled trial to assess the efficacy of pregabalin in reducing neuropathic pain after TKA. Two hundred forty patients awaiting TKA were randomized into one of two treatment arms, placebo or pregabalin. Patients were instructed to take either placebo or pregabalin 300 mg 1 to 2 hours preoperatively followed by a twice-daily tapered dose until postoperative day 14.²⁹ Analysis revealed statistically significant decreases in epidural and oral opioid use and in the incidence of neuropathic pain in the pregabalin arm at 3 and 6 months postoperatively (pregabalin arm: 0% and 0% and placebo arm: 8.7% and 5.2%). Furthermore, analysis revealed a statistically significant increase in active knee range of motion in the pregabalin arm to postoperative day 30.²⁹ Not surprisingly, analysis also revealed statistically significant increases in sedation and confusion in the pregabalin arm on postoperative days 0 and 1, without an increase in hospital LOS between treatment arms.²⁹

The study by Buvanendran et al²⁹ clearly supports the pain control efficacy of pregabalin in both the acute and chronic postoperative periods. Nonetheless, Paul et al³⁰ conducted a randomized placebo-controlled trial to assess the efficacy of gabapentin in reducing morphine consumption after THA, which revealed no clinically important reduction in the gabapentin arm.³⁰ Hamilton et al²⁶ conducted a meta-analysis to assess the effect of gabapentinoids on postoperative pain intensity after TKA, which corroborated the results of Paul et al.³⁰ Twelve RCTs comparing gabapentin or pregabalin with placebo or no treatment in patients undergoing TKA were included in the meta-analysis, which revealed no clinically important reduction in pain scores with gabapentinoid use at 12, 24, 48, or 72 hours postoperatively.²⁶ Furthermore, in June 2020, Verret et al³¹ published a systematic review and meta-analysis that assessed the effect of perioperative gabapentinoids on postoperative pain and adverse events. Two hundred eighty-one RCTs, including 24,682 patients, comparing gabapentin or pregabalin with control arms in adult patients undergoing surgery were included in the meta-analysis. Analysis did not reveal a clinically significant analgesic effect in patients treated with perioperative gabapentinoids. The risk of postoperative nausea and vomiting was decreased, but dizziness and visual disturbance were increased.³¹

Only gold members can continue reading. Log In or Register to continue