| Introduction |
Pain is classified as the "fifth vital sign" ; Its management is key to improving the quality of life (QoL) of patients. Pain is defined as an "unpleasant sensory and emotional experience associated or appearing to be associated with actual or potential tissue damage."
Pain has several classifications depending on its anatomical, etiological, chronicity (duration), intensity, and pathophysiological characteristics.
Acute pain is one of the most common reasons for seeking medical attention in the emergency department (ED). Low back pain (LBP) is the main cause of limitation and absence from work worldwide. Occupational factors are key causes of DL. Migraine-related pain is another major cause of disability.
In general, challenges in pain management are found at the level of patients (i.e., culture, experience, education, and health status), health professionals, and the health system. These challenges are multiple and stem mainly from undertreatment, the inability to assess initial pain, the unavailability of pain management guidelines, and the lack of recognition and documentation of pain. A major contributing factor is the misuse and abuse of opioids at unacceptable levels.
The dynamic nature of pain and its intensity highlight the importance of “stratified care ,” an approach to treating pain according to the risk category (i.e., low, medium, or high risk of poor outcomes) of patients. In these circumstances, treatment guidelines can assist in evidence-based decision making.
| Expert recommendations for clinical pain management in Qatar |
> Management of acute pain in the ED
Acute pain is the neurophysiological response to noxious injuries that lasts less than 3 months. Includes postoperative pain, fractures, appendicitis, and soft tissue injuries. Acute LBP is a common cause of ED consultation.
> Pain assessment
The visual analog scale (VAS) and numerical pain rating scale (NRS) are commonly used for the assessment of pain intensity. The 4-point Verbal Categorical Scale (VRS) is not recommended.
> Pharmacological treatment
Analgesics have varied physiological mechanisms and are therefore chosen depending on the severity of the pain.
• Acetaminophen (paracetamol): Widely used for its antipyretic and analgesic effect. It is very selective and has an additive effect; However, it does not have a synergistic effect when combined with other nonsteroidal anti-inflammatory drugs (NSAIDs). It is available both orally and intravenously (IV) at an approved dose of up to 4 g/day due to its hepatotoxicity. It has demonstrated an analgesic effect similar to that of NSAIDs. It can be used IV in hospitalized patients to treat pain with an opioid-sparing effect and fewer side effects than morphine.
• NSAIDs: They act by inhibiting COX enzymes and are proposed as first-line drugs for mild to moderate pain. They are contraindicated in elderly patients and in those with peptic ulcer, hypertension, kidney disease or liver failure. They should also be avoided in patients with a history of myocardial infarction, transient ischemic attack, stroke, or inflammatory bowel diseases.
In general, NSAIDs are more effective than opioids, but without additional benefits when combined with opioids or muscle relaxants in acute pain. IM use of diclofenac and IV administration of acetaminophen have comparable efficacy in relieving pain.
Ketorolac has a similar effect to naproxen for mild to moderate LD reduction, but with faster relief. Additionally, IV administration of parecoxib sodium (40 mg) may be an alternative to morphine sulfate 0.1 mg/kg in cases of acute traumatic pain in EDs. Topical NSAIDs are also used for chronic musculoskeletal pain.
• Weak opioids: Tramadol has two independent mechanisms to produce analgesic effects: the opioid mechanism (binds to the m-opioid receptor) and the non-opioid mechanism (inhibits the reuptake of serotonin and norepinephrine), with fewer opioid side effects.
Codeine is another weak opioid that is available in combination with acetaminophen.
• Strong opioids: Effective in the treatment of pain but with several limitations, as they are associated with an increased risk of respiratory depression, sedation and addiction. Evidence has shown effective pain relief with oral and parenteral use of strong opioids in patients with severe acute pain, although with increased risk of AEs, especially dependence. Therefore, the use of strong opioids should be restricted and patients should be referred to a pain specialist for interventional management modalities.
| Expert recommendations for the treatment of chronic pain |
Pain that lasts more than 3 to 6 months after an acute injury or illness is called chronic pain and has several pathophysiological causes. The effect of chronic pain is multiple, such as a negative influence on QoL, depression, anxiety, disruption of daily routine, reduced social activity, disability, sleep disorders, and increased costs of care.
> Chronic pain evaluation
The PainDETECT, Douleur Neuropathique en Four Questions and Leeds Assessment of Symptoms and Signs of Neuropathic Pain are some of the validated questionnaires used to assist clinicians in the assessment of chronic pain.
> Pharmacological treatment
• NSAIDs : NSAIDs are the first-line agents for mild to moderate pain and the first step in the treatment of chronic pain. However, long-term use of agents such as diclofenac, ibuprofen, and COX2 inhibitors may cause an increased risk of death from myocardial infarction and coronary heart disease, but not naproxen.
• Acetaminophen (paracetamol): Insufficient evidence supports the use of acetaminophen in chronic LBP. It is generally less effective than NSAIDs in relieving chronic LBP and knee and hip pain in patients with osteoarthritis, while the ibuprofen/acetaminophen combination is significantly superior to acetaminophen alone, but with an increased risk of GI bleeding.
• Opioids: They have limited effectiveness in the treatment of chronic pain. Evidence suggests that opioids are effective in treating chronic pain for up to 3 months. Its for non-cancer pain should be indicated with caution and under supervision.
| Neuropathic pain |
It is pain caused by an injury or disease of the somatosensory nervous system, which is further classified as peripheral or central.
> Pain assessment
The Profile of Mood States, Hospital Anxiety and Depression Scale and the Depression, Anxiety and Stress Scale are commonly used to identify the presence of psychosocial consequences of neuropathic pain.
> Pharmacological treatment
• Tricyclic antidepressants (TCAs): TCAs, such as amitriptyline, are recommended as first-line treatment for pain due to peripheral neuropathy, postherpetic neuralgia, traumatic spinal cord injury (SCI), chronic neuropathic pain, and painful diabetic neuropathy. Amitriptyline and nortriptyline have comparable efficacy in the treatment of peripheral neuropathic pain. The most common AEs of these agents are nausea, dizziness, drowsiness, dry mouth, diarrhea, constipation, and hyperhidrosis.
• Serotonin-norepinephrine reuptake inhibitors (SNRIs): SNRIs are also recommended as first-line therapy for neuropathic pain. Duloxetine and venlafaxine significantly reduce the intensity of neuropathic pain. The most common AEs are nausea, dizziness, drowsiness, dry mouth, diarrhea and constipation.
• Anticonvulsants: Anticonvulsants commonly used for neuropathic pain are gabapentin and pregabalin. Pregabalin showed significant pain relief in chronic central neuropathic pain after SCI. However, promising results are not shown in patients with neuropathic pain due to chronic lumbosacral radiculopathy and in those with central post-stroke pain.
• Opioids: They are recommended as second, third and fourth line therapy for neuropathic pain since long-term use is associated with a high risk of AEs and abuse. Weak opioids, such as tramadol, may be considered. It is advisable to consult a pain specialist for interventional management modalities.
| Discussion |
Pain is a major health problem and one of the most common reasons for hospital consultation worldwide. Pain management is an evolving area in Qatar, and there is same undertreatment in the country due to the stigma associated with painkillers.
The most appropriate treatment option for a patient with acute pain is paracetamol due to its additive effect.
The second-line option is NSAIDs for acute pain of moderate intensity and referral to a pain specialist for pain of severe intensity. For the management of chronic pain, non-pharmacological and non-opioid therapies should be considered.
Doctors should refer patients to a pain specialist if the patient needs opioid treatment. The pain specialist should discuss with patients the risks and benefits of such treatment.
For neuropathic pain, antiepileptic drugs, SNRIs, and TCAs are recommended as first-line treatment. Topical lidocaine and topical capsaicin are considered second-line options, while NSAIDs are not recommended for neuropathic pain.
A standardized treatment strategy for various types of pain could help optimize pain management, which is currently an unmet need in Qatar.
| Conclusion |
The panel strongly recommended avoiding opioid use when possible and referring the patient to a pain physician for interventional management modalities as needed. These recommendations will be periodically re-examined and updated based on future developments.
