I am a
Home I AM A Search Login

Making Sense of Pain Assessment After Surgery



The 2024 Global Year will examine what is known about sex and gender differences in pain perception and modulation and address sex-and gender-related disparities in both the research and treatment of pain.

Learn More >

Pain among hospitalized patients is expected and thus pain assessment is a crucial step towards its appropriate management. The first day after surgery, around 20-40% of patients will experience severe pain. Some surgical procedures cause more pain than others, especially orthopedic and trauma procedures on the spine or extremities (i.e., knee/hip replacement, spinal reconstruction, etc.). This needs to be considered when choosing the appropriate pain treatment. 

Pain treatment after surgery is not meant to make the patient pain-free, which is a common misconception. It is meant to manage the pain so that it is bearable. Patient pain is commonly assessed using a numeric pain rating scale, where patients are asked, “How would you rate your pain on a scale from 0 to 10, if 0 means no pain and 10 means the worst pain imaginable?” On average, pain ratings of 4 or less (mild-to-moderate pain intensity) have been deemed acceptable by patients who have undergone surgery (here and here). Yet, patients were more satisfied with their pain treatment if they had pain ratings of 3 or less. Other hospitalized patients find severe pain acceptable as long as it resolves. 

Despite its widespread global use, health professionals and researchers agree that sole use of a numeric pain rating scale to assess pain (i.e., pain intensity) is insufficient to capture the entire pain experience for patients.

Moving beyond the sole use of a numeric pain rating scale

The surgical pain experience varies between patients and is known to be multidimensional, meaning that pain affects a number of biological, psychological and social functions (also referred to as biopsychosocial functioning), and those functions affect the pain experience. This underscores the importance of assessing other aspects of the pain experience, such as the effects of pain on functioning, rather than just pain intensity.

Based on a study from 2016, patients agree that their pain experience is unique and cannot be captured by a numeric pain rating scale. Some of these patients who live with chronic pain also struggled with rating the acute pain they experienced after surgery, as their chronic and acute pain tended to differ in intensity. This study also explored an extreme of the numeric pain rating scale. One could question how patients would know what the worst imaginable pain is, and some patients were unsure whether they had yet to experience the worst imaginable pain for a human being. 

What is expected to be gained by assessing the effects of pain on functioning in addition to pain intensity? If pain interferes with function, the pain intensity that patients find acceptable after surgery is lower than if the pain does not interfere with function (ratings of 3 or less on the numeric pain rating scale as opposed to 4 or less). Therefore, assessing both pain intensity and function in hospitalized patients likely results in better pain control.

Evidence-based functional pain assessment tools are already available and include the CAPA Tool, the ABCs of Pain Scale and the American Pain Society Patient Outcome Questionnaire. Comfort, mood, movement and sleep are examples of domains assessed with these tools, and some can also assess changes in pain, pain control and side effects.

Communication is key to better pain assessment

Patients and health professionals tend to have different views on whether a patient’s pain is considered unbearable. We know that physicians tend to rate patients’ pain lower than the patients themselves and this inability to fully understand the extent of a patient’s pain can pose a threat towards the patient obtaining adequate pain management. 

When communicating with the patients, it is important to discuss expectations regarding the pain experience. The use of personalized pain goals has been suggested to improve the management of cancer pain and defined as the “maximal self-reported pain intensity score on a 0-10 numerical rating scale at which the patient will consider comfortable in physical, functional and psychosocial domain.” In other words, what is the highest pain rating that won’t disrupt a patient’s sleep, mental health, social relationships and/or physical activity in their view?

Moreover, it has been said that “pain is a social transaction between patients and clinicians.” The clinician assesses the patient while the patient presents their pain experience or vice versa, and they work together on finding a solution and choosing an appropriate treatment/prevention strategy. By improving this social transaction, patients’ experiences and outcomes will likely be improved too. 

Continuously working to improve pain assessment and communication between patients and clinicians is key to success. Also, since the views of when pain is considered bearable and unbearable differ between patients, personalized pain goals might be important to consider in surgical settings as well.

Pain assessment and management go hand in hand

Pain assessment guides pain management, as treatments can be chosen based on pain severity. For instance, opioids are generally effective for treating moderate-to-severe pain, however, there are several studies that show non-opioid medications (e.g., NSAIDs [non-steroidal anti-inflammatory drugs] such as ibuprofen) can also treat moderate-to-severe pain effectively (here, here and here). Even more effective is the combination of different types of pain medications (e.g., NSAIDs and paracetamol/acetaminophen such as Tylenol).

Caution is necessary when administering opioids since they are potent drugs (i.e., low drug concentration can lead to pain relief) and can also be highly addictive. This has led to many issues we are facing today, especially in North America, such as opioid use disorder (when “a person uses opioids even though it causes harm to themself or others”), illicit opioid use and overdoses. 

In Canada, approximately 20 people die every day from substance use poisoning where at least one substance is an opioid. Since opioids are commonly used to treat acute surgical pain, and sensitivity to opioids is known to differ between patients (as does the risk of opioid use disorder), this needs to be considered in surgical settings. 

There are several reasons why we want to enhance pain assessment and management practices. Inadequate pain management has been linked to adverse psychological and physical patient outcomes (e.g., suppression of the immune system, increased risk of infection and poor wound healing), and affects recovery after surgery. If the patients’ pain affects their ability to move and take deep breaths, then it can increase the risk of dangerous blood clots and pneumonia. 

When is pain management considered inadequate? In a study from 2018, researchers found a heightened connection between cancer patients whose pain interfered with their daily life and inadequate pain management. Nevertheless, many patients, who were expected to receive acceptable pain management, still reported pain interfering with function. This underscores the importance of not only assessing pain intensity but also assessing the effect of pain on function.

Selecting and implementing a functional pain scale in Alberta

At Alberta Health Services, we are currently working on selecting and implementing a functional pain scale to better assess pain in surgical patients. Currently, we have identified a wide range of pain-related tools and are working toward selecting one functional pain scale that will best fulfill our needs for in-hospital pain assessment surrounding surgery. 

We do not believe that implementation of a functional pain scale will replace the numeric pain rating scale but, when combined, will help to enhance pain control and surgical recovery and therefore patient experiences during hospitalizations.

We believe that a multidimensional pain rating scale can help us to ensure the adequate management of patients’ pain. We know that if the pain affects a patient’s ability to function, the pain rating threshold considered as acceptable decreases. Therefore, we expect that our pain management practices will be improved by both assessing pain intensity and the interference of pain on function. 

We hope that these changes in practices can be a positive step towards addressing part of the opioid crisis in Alberta (e.g., after COVID-19, there are more unintentional opioid poisoning deaths across the province), and that more patients will be recognized as partners in the assessment of pain after surgery.  This might help patients to feel more confident when asked to rate their pain.

Simona Denise Frederiksen, Knowledge Translation Consultant
Surgery Strategic Clinical NetworkTM, Alberta Health Services, Calgary, Canada

Kayla Denness, Senior Practice Consultant
Surgery Strategic Clinical NetworkTM, Alberta Health Services, Calgary, Canada

Daniella Anderson, Provincial Project Manager
Surgery Strategic Clinical NetworkTM, Alberta Health Services, Edmonton, Canada

Tracey Geyer, Team Lead/Senior Health Planner
Planning and Performance, Alberta Health Services, Edmonton, Canada

The Surgery Strategic Clinical NetworkTM is funded and the authors are employed by Alberta Health Services

Thanks to Health Canada’s Substance Use and Addictions Program (SUAP) for funding

Share this