What’s in the web for family physicians – Pain management basics

Fiona PY Tsui 徐佩儀, Carina CF Li 李靜芬, Alfred KY Tang 鄧權恩

HK Pract 2019;41:47-48

Pain is a common presenting symptom of a wide range of medical conditions. Persistent pain or pain disorders can also adversely affect patient’s well-being and lead to other co-morbidies (e.g. anxiety and depression). The prevalence of chronic pain in Hong Kong adults has increased from 10.8% in 1999 to 28.7% in 2017.¹ It is therefore important for family physicians to learn about how to recognise, assess and manage pain.

Definition of pain and related terms

The International Association for the Study of Pain (IASP) defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”. In simple words, pain is what the patient say it hurts. This reflects the fact that while most pain symptoms come with a related tissue damage (e.g. sprained ankle), it can also occur in absence of such damage (e.g. idiopathic trigeminal neuralgia).

Basic framework of pain management

The Essential Pain Management provides a framework for basic pain management. It uses the acronym “RAT” to represent the Recognition, Assessment and Treatment of pain.

Recognise – Pain is a perception and is always subjective. The best way to recognise pain in a patient is to ask for the presence of it.

Assess – It is essential to classify the type of pain and its severity before deciding on treatment. In general, pain can be classified into acute vs chronic, nociceptive vs neuropathic, and cancer vs non-cancer. Commonly used pain severity scales include the numeric rating scale (0-10), visual analog scale (0-100mm), and verbal descriptive scale (none, mild, moderate, severe).

Treat – Treatment of pain can be broadly divided to pharmacological and non-pharmacological modalities. While simple pain can be managed with monotherapy, complex pain cases will usually require a multidisciplinary approach.

Screening tool for identifying neuropathic pain in Hong Kong population

The prevalence of neuropathic pain is about 9.03% in Hong Kong.¹ Neuropathic pain is a pathological pain state due to a lesion or disease of the somatosensory nervous system. It is characterised by presence of neuropathic features, such as burning, lancinating, pins and needles like, numbing. It is often accompanied by sensory changes such as allodynia. It may be difficult for Cantonese or Mandarin speaking patients to describe neuropathic pain as these are not terms commonly used in our language. The ID Pain Questionnaire is a simple validate tool for detection of neuropathic pain in Hong Kong population. However one should note that the ID Pain Questionnaire do not replace a proper pain assessment.

WHO analgesic ladder for cancer pain

The WHO has developed a simple 3 steps analgesic ladder to guide pharmacotherapy for cancer pain. Clinican can choose to use appropriate analgesics from each of 3 steps according to the patient’s pain severity. It is important to note that the analgesics should be given regularly (by the clock) and orally (by the mouth). Depending on patient’s physical status, alternatives such as non-oral route preparations (e.g. transdermal opioid patches) or pain interventions (e.g. neurolysis) may be considered as adjuncts. Attention should also be made to analgesic related side effects, especially opioid induced ventilatory impairment. As a general rule, one should always “start low and go slow” when titrating analgesics to achieve the desired effect.

Hazardous co-prescription with opioids and benzodiazepines

It is not uncommon for chronic pain patients to visit different presecribers for multiple prescriptions. In Western countries we are seeing an increasing number of opioid-related deaths and occasionally the prescriber gets sued. It is therefore prudent to screen for any concomittent sedative or strong opioid use before prescribing any drug from these 2 classes. It is also worth noting that the evidence in benzodiazepine or opioid in managing chronic non-cancer pain remains poor.

Online resources on pain topics

The IASP website contains rich resources for health professionals interested in pain management. Useful sections include the IASP Clinical Updates, where you can find short update articles on different pain topics written by their experts in the respective field. The IASP Global Year section also contains articles written by different health professionals related to the year’s theme.

Online course for non-pain specialists

The Faculty of Pain Medicine, a faculty of the Australian and New Zealand College of Anaesthetists, is one of the world leading academia in pain medicine training. It offers the Better Pain Management program which is available online to non-pain specialists. This online program also serves as an introductory module to the faculty’s trainees.