Interest in strategies to minimize the intraoperative and postoperative use of opioids has skyrocketed over the past 5 years. With the fallout of 'The Opioid Crisis', physicians have reflected on changes they could make in the day-to-day management of pain in patients having a surgical procedure.
While the complexities of the opioid crisis are out of scope for this article, there has been increased scrutiny in every step of the surgical process to identify where alternative pain management techniques to opioids could be utilized. The result has been efforts towards 'opioid-free anesthesia', 'opioid-free analgesia' and 'opioid-sparing modalities'.
This recent journal publication from Anesthesiology was the basis for this blog post. While I agree with the efforts to decrease the number of opioid pills that are prescribed and end up in US households, I also fear the wide-sweeping proclamations that the ultimate goal should be 'opioid-free surgery'. Check out the pdf here. https://bit.ly/2Tp5xp7
In this article, I will accomplish the following:
- review definitions
- discuss the difficulties of assessing success
- the practical limitations
- how to provide the best assessment and treatment of patients undergoing surgical procedures while being mindful of the burden of overuse and overprescription of opioid medications
We are all aware of the challenges associated with opioid use and prescription in the existence of 'The Opioid Crisis' which was the culmination of several initiatives including declaration of the first decade in 2000 as the 'Decade of Pain Control and Research', prescribing opioids to improve patient satisfaction, declaring pain control a human right (without clarifiers), and questionable actions by pharmaceutical companies. Because deaths from prescription opioids as well as illicit opioids skyrocketed and closer review revealed liberal oral prescriptions after even minor surgical procedures, medical providers reflected on changes they could make to mitigate this situation. As such, opioid-free strategies, opioid-free anesthesia, opioid-free anesthesia have come to the forefront of quality initiatives that can affect every phase of the perioperative period.
There are a couple of distinctions that I think are important to make. There are two phases of care that must be considered. First is the apparent over-prescription by some in the past of opioids for surgical procedures. The second is that long-term opioids were continued to be prescribed for individuals with chronic pain conditions. Addressing these two situations are complex and a one-size-fits-all approach is not appropriate and attempting to do so can have negative ramifications. Speculation has been made that providing opioids during a surgical procedure may be associated with persistent opioid use or an opioid use disorder. However, the only consistent factor present are the opioids themselves; the remaining characteristics of these individuals is so heterogeneous that it is exceedingly difficult to determine what truly is the driver to these problems. The long-term prescription of opioids for chronic pain is a complex topic on its own and out of scope for discussion in this article. I will address this in a future blog however.
At the same time, the increased prescription of opioid tablets, sometimes far exceeding the patient's true needs, results in a stockpile of opioids (and other medications) in the home medicine cabinet and are then available for misuse. This IS a huge problem and I commend those leaders who have taken a critical look at our prescribing practices and have determined some standardization around the number of tablets to dispense to an individual based on experience with other patients.
Opioid-sparing anesthesia - using local anesthetics, regional anesthesia techniques, and non-opioid based multimodal pain management to minimize or eliminate opioid usage in the intraoperative / postoperative period
Opioid-free anesthesia - the combination of various opioid-sparing techniques leading to the disappearance of intraoperative opioids
Opioid-free analgesia - avoidance of opioids in both the intraoperative period and the postoperative phase
Be aware that these definitions can be interpreted in different ways by different researchers. One must critically assess the specifics regarding medication administration and not jump to conclusions based on the labeling of the medication approach.
Determining the Goal of the 'Opioid-Free' Movement
In an effort to reduce the available medications that remain in the home unused after a surgical procedure, the concept of 'opioid-free' surgeries was introduced. An additional driver was the hypothesis that administration of opioids at any point during the perioperative period (during or after surgery) lead to an increased risk of persistent opioid use. When pain persisted after surgery, and the provider failed to prescribe additional opioids, individuals sought easier-to-access illicit opioids for their pain. Health care providers reflected on their contributions to the opioid crisis and pondered whether utilization of strategies other than opioids could safely and effectively get a patient through a surgical procedure. But is that enough?
Challenges with the Pain Experience
The IASP defines pain as 'an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage'. This is true for not only chronic pain but for acute pain as well. The differing experiences of individuals need to be taken into consideration when developing a pain management plan. (Image below courtesy of Stefan Friedrichsdorf MD).
Some individuals may present to surgery with pre-existing pain, and some will be using opioids, both of which will impact the manner in which a patient copes with a new acute pain. Moreover, there are several comorbid states that might be present and have an undeniable impact on the process of nociception (perception of a painful stimulus). Anxiety, depression, societal pain, poor sleep, psychological pain, mental health issues, social pain, spiritual pain, racial disparity all add up to a heightened pain experience.
A further challenge is how to measure the pain experience. Given there is no reproducible objective measure of pain, we must rely on self-report of pain score (Numeric Rating Scale, for example) as an indicator of a patient's pain. We know these reports are subjective and, as mentioned above, are colored not only by the pure pain stimulus but that stimulus is filtered through our brains based on past pain experiences, coping styles, what the pain represents to us, etc. While we are taught in medical school that 'the pain is what the patient states it is', we do need to be cautious of responding purely to the pain score a patient reports. However, trends in these scores CAN be helpful and are just one of the indicators of improvement after a surgical procedure.
Pitfalls of Multimodal Analgesia
From Shanthanna 2021
Multimodal analgesia is the use of multiple agents and techniques in the intraoperative and postoperative period to address pain. Multiple agents are considered to target the numerous receptors responsible for nociception. The typical agents used are shown above.
But just because we have the capability of infusing multiple agents during surgery, does it mean this is best practice? The authors of the aforementioned article argue that many of these agents are limited by a ceiling effect and often cannot be titrated to effect and address breakthrough pain that could occur in the postoperative setting. Exceeding the maximum dose may result in organ toxicity or appearance of undesired side effects (bradycardia, hypotension in the case of dexmedetomidine or tachycardia, anxiety, hallucinations in the case of ketamine). Infusing multiple agents simultaneously could result in safety and drug interactions. There may be resource limitations (infusion pump availability, personnel, monitoring capabilities) that would make the delivery of multimodal analgesia exceeding difficult. I would also argue that there could be inconsistent application of these various modalities and no tool currently exists to address what I think is needed: a systematic approach to pain based on the expected intensity of pain. To support this belief, researchers in one study found that only 14% of patients undergoing surgical procedures were prescribed a combination of two or more medications for pain. Even with more simple approaches to pain, we still have yet to optimize the prescription and administration of medications despite ample evidence of this benefit (scheduled acetaminophen and NSAIDs for moderate to severe pain, for example). To ignore this fact will further increase the disparity in pain treatment. Some individuals will reap all the benefits; others will have their pain complaints ignored or invalidated.
Despite the definitions reviewed above, there may be quite a bit of variation in practice with regard to 'opioid-free' and exactly what that entails. For example, even in 'opioid-free' protocols, some patients were administered fentanyl for induction or had remifentanil infusing during the case. One must also consider if there were attempts to standardize the anesthetic technique. For example, ideally certain aspects of the anesthetic are kept the same to assure that the only differences are the medications that are being studied. In some studies, patients who received opioids did not receive any multimodal agents (which as mentioned above is the standard of care). For example, patients receiving opioids should also be prescribed scheduled acetaminophen and NSAIDs, unless contraindicated. Doing so may allow for a smaller dose of opioid to be administered and a decrease in the side effects from opioids. To withold these analgesics brings into question 'What exactly are we measuring?'.
An additional problem that is not often addressed in literature about 'opioid-free surgery' is the fact that the opioid epidemic is a social problem, not merely a prescribing problem. While it may be beneficial to explore the various tools we have to minimize use of opioids, the emotional and social components of pain simply cannot be managed with more medication infusions. Along with the pharmacologic approaches to pain, we must address the mental health reforms that need to occur to provide better care of this population.
Perhaps one of the more disappointing findings of some of these studies thus far is that there is little evidence to suggest that limiting intraoperative opioids influences the risk of persistent opioid use. To further complicate the matter, Shanthanna cited there was evidence of 29 different definitions of 'persistent opioid use' in the literature. It could be argued that 'persistent opioid use' may also be the sole result of a provider continuing to prescribe these opioids rather than addressing the persistent pain from a psychological and coping perspective. In today's busy clinic setting, it is often faster and easier to prescribe a medication that to engage in conversation or refer a patient to other services for coping strategies.
It Is Not about Opioids but How We Use Them
While it is admirable to reflect on how we as physicians can positively contribute to minimizing the risk of opioids, I do not believe that we should completely disregard the benefits of appropriately-used opioids. This class of medication has stood the test of time, now being used for nearly 5,000 years. While other medications have been replaced by newer classes in an effort to minimize side effects and toxicities, opioids hav