Identify Patients at Risk for Persistent Postoperative Opioid use or Misuse
The first practical step anesthesiologists can take is to identify patients at risk for postoperative persistent opioid use or misuse. Investigators have identified several risk factors for prolonged opioid use or opioid misuse (Figure 1). Those of potential relevance to anesthesiologists conducting perioperative evaluations include current opioid use,[11,63–65] previous history of opioid use,[66,67] current or previous substance use disorder,[11,56,66,68–75] smoking,[56,71,76,77] coexisting psychiatric disease (particularly anxiety and depression),[30,33,56,65–68,70,73,74,77–81] more medical comorbidities (higher Elixhauser comorbidity index), history of chronic pain,[11,69,71,82,83] and younger age.[64,66,67,69,70,77] Conflicting evidence exists for sex,[11,64–68,75,77] although studies focused on perioperative prescribing have identified female sex as a risk factor for persistent postoperative opioid use consistent with studies of chronic pain conditions.
What to do Once you Have Identified Patients at Risk
Set Expectations. Anesthesiologists can play a key role in setting patient expectations for pain management during the perioperative period. Doing so may help mitigate risk for postoperative opioid use and subsequent persistent use and misuse. For example, a systematic review incorporating 3,523 surgical patients found that lower expectations of postoperative pain correlated with lower actual postoperative pain in 8 of 13 identified studies. However, patients with erroneous expectations that they should have no or minimal pain in the postoperative period may request or consume more opioids if their pain is greater than anticipated. Between 10 and 36% of postoperative patients expect complete analgesia from pain medication,[85–87] which is inconsistent with normal postoperative recovery and represents an unreasonable expectation of the efficacy of opioids. A brief conversation in the preoperative holding area to set appropriate expectations for postoperative acute pain (e.g., "You will have pain after surgery. You will receive medication for your pain, but it is not likely to take away all of your pain.") may be feasible for anesthesiologists in every practice setting. Further research is warranted into whether this is particularly beneficial for patients having surgeries with high incidences of postoperative acute pain such as spine or thoracic surgery.
Coordinate Transitions of Care. Most preoperative chronic opioid users have a "usual prescriber," and a return visit within 30 days of surgery with the usual prescriber is associated with decreased odds of high-risk opioid prescribing (multiple prescribers, co-prescribing of benzodiazepines, high-dose opioid prescriptions, and new long-acting prescriptions). Those without a usual prescriber also show more high-risk prescribing postoperatively. While these data are derived from an administrative claims database rather than a longitudinal cohort, the concept of engaging the usual prescriber in the perioperative course is consistent with the spirit of a transitional pain service.[59–62] Consequently, elective surgical patients with preexisting pain or substance use disorders but without pain or addiction medicine specialists can be referred to establish care that can continue through the phases of perioperative care. Anesthesiology groups with dedicated preoperative evaluation and acute pain services are well positioned to coordinate this care; otherwise, operating room anesthesiologists can communicate these concerns to the surgical service.
Patients with chronic pain and those at risk for the development of chronic pain postoperatively may also benefit from care at a specialized transitional pain clinic before surgery.[59–62] Pain physicians at these centers evaluate such patients preoperatively, help manage expectations regarding postoperative pain control, and make recommendations to anesthesiologists and surgeons about intraoperative and immediate postoperative pain management, including postdischarge tapering plans.[89,90] After discharge, patients continue to be followed in the clinic in order to ensure that acute and subacute pain are managed appropriately, and to minimize the risk of transitioning to new chronic pain or exacerbating extant chronic pain. Managing these at-risk patients properly with nonopioid medications, interventional techniques, and psychologic counseling has been hypothesized to lessen their chances of developing harmful postoperative opioid use patterns. While there are some early descriptions of pre-post data suggesting decreased postoperative opioid consumption for both opioid-naïve and -tolerant patients after implementational of transitional pain services,[59,92] we lack high-quality data on the efficacy and cost-effectiveness of transitional pain clinics. One thoughtful viewpoint examines the business case for such clinics. In their absence, anesthesiologists can encourage referrals to a pain medicine specialist or engaged primary care provider for potentially challenging patients.
Optimization of Preoperative Opioid use
Opioid Tapering and Cessation. About 20% of patients presenting for surgery use opioids preoperatively, with frequency and dose varying with the type of surgery. Given concerns that preoperative opioid use may increase postoperative morbidity and healthcare utilization, there has been increased attention paid to preoperative opioid weaning and cessation programs. There is particular interest in weaning patients using high doses preoperatively, generally defined as greater than 90 oral morphine equivalents daily.
A proposed template for such a high-dose opioid taper program involves regular clinic visits over a 10- to 12-week period to assist with both opioid dose reduction and palliation of withdrawal symptoms. Participating patients have their opioid doses weaned by approximately 10% weekly if tolerated. While clinical discretion is needed and care should be tailored to the individual, we have provided a sample weaning protocol for a hypothetical patient (Table 1). Preliminary studies suggest these programs may improve postoperative outcomes. A retrospective matched cohort study comparing 123 total knee or hip arthroplasty patients divided into three equal groups (opioid-dependent patients who weaned their dose by 50% or more preoperatively, opioid-dependent patients who did not wean their dose, and opioid-naïve controls) found that the weaned group and the opioid-naïve group had improvements in pain and functional outcomes (Western Ontario and McMaster Universities Osteoarthritis Index, University of California, Los Angeles activity score, and Short Form 12 version 2 Physical Component Score) that were significantly larger than those of the nonweaned group. Of note, the weaned group improved to a similar degree as the opioid-naïve group but did not reach the same absolute level of function because patients on opioids preoperatively had lower baseline scores. Furthermore, preoperative opioid use was self-reported by patients. Given the resources and time required, further study is needed to ensure preoperative weaning will improve outcomes before such care becomes a standard of care. Moreover, lengthy opioid weaning programs require close coordination with surgeons, who may hesitate to delay surgery for a 2- to 3-month wean. An additional potential consideration is that large-scale observational data have identified an association between cessation of opioid therapy and overdose or suicide, although these data are not limited to preoperative weans.[98,99] Patients and caregivers can be engaged in the decision to wean after explanation of the potential benefits. Continued monitoring and support of patients may be warranted in the context of opioid cessation whether it occurs before or after the operation.
Anesthesiology. 2022;136(4):594-608. © 2022 American Society of Anesthesiologists | Lippincott Williams & Wilkins