Pain is one of the most common symptomatic complaints from patients in all healthcare areas, and your role in pain management is crucial as a nurse. However, to manage pain effectively, we must understand its pathophysiology and tailor our care plan to each patient. These notes will give an overview of what pain is and the different classifications of pain.
What is Pain?
Pain is an unpleasant sensory or emotional feeling that arises from actual or potential tissue damage. The International Association of Pain has determined six key concepts we must understand when discussing pain.
Pain is always an individual experience affected by different factors, including biology, psychology and social status.
Pain and nociception are not the same, and pain does not necessarily have to emerge from activity in sensory neurons.
As individuals, we learn about the idea of pain through our own life experiences.
We should always respect how others perceive and interpret their pain experience.
In some cases, pain may promote an individual’s ability to cope with a situation. However, it also negatively affects one’s function and social and psychological well-being.
Several behaviours indicate pain, and we can not exclude the fact that some people and animals might feel pain but cannot communicate their experiences.
What they’re saying with all this is that pain is unique to every individual, and as nurses, we must treat it as such.
Acute vs Chronic Pain
Pain is divided into two main categories: Acute pain, which refers to pain that lasts for a short duration, and Chronic pain, which refers to long-term persistent pain, or intermittent pain with exacerbations.
In most cases, acute pain occurs because the individual is experiencing a specific illness or has injured their tissues by trauma, surgery or burns. The pain is associated with spasms in the skeletal muscles and sympathetic nervous system activation, and it serves the biological purpose of alerting the individual that something is wrong. Moreover, acute pain follows a normal healing process and is often resolved by treating the underlying cause and can be managed well with analgesia.
Chronic pain, however, is pain that lasts more than three months, and its cause is often not identified. It serves no biological purpose and has no recognizable end-point, even if a disease or injury provokes it as chronic pain does not follow the normal healing pathway. In addition, chronic pain may arise or be aggravated by psychological problems.
When treating chronic pain, medical professionals further subdivide the category into pain originating from cancer and pain not arising from cancer. The root cause of non-cancerous chronic pain varies widely, but some of the most common causes include diabetic peripheral neuropathy, back and neck injuries and osteoarthritis.
The Tree Types of Pain
1. Nociceptive Pain
Another common way to classify pain is according to its pathology. When you place your hand over a sharp object, you can feel the pressure translating into pain. This feeling warns your brain that you’re about to injure yourself if you continue. If you keep pressing and hurt yourself, your injured tissues send the pain signal to your brain, indicating that you now have a problem. These warning signals are called Noxious Stimuli, and they are completely normal in how they are triggered and perceived by our bodies. When pain occurs through this normal pathway, it is known as Nociceptive Pain.
2. Neuropathic Pain
The second type of pain is Neuropathic pain which results from a lesion or illness affecting the somatosensory system. Ectopic sites generate impulses due to damage or dysfunction of the peripheral or central nervous system. The ectopic impulses create the feeling of pain in the innervated area, known as positive symptoms. At the same time, the nerve damage creates sensory deficits in the innervated area, causing negative symptoms.
3. Nociplastic Pain
Nociplastic pain is more complex because the patient’s complaint will be the only evidence and symptom of its occurrence. Despite the many investigations and tests, there would be no evidence of where the pain is coming from. Their tissues would seem normal without any damage or potential threats that could activate the peripheral nociceptors. And there would be no evidence of any conditions or lesions that could trigger pain through the somatosensory system.
Woolf C. J. (2010). What is this thing called pain?. The Journal of clinical investigation, 120(11), 3742–3744. https://doi.org/10.1172/JCI45178
Chen JS, Kandle PF, Murray I, et al. Physiology, Pain. [Updated 2021 Jul 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK539789/
Bonezzi, C., Fornasari, D., Cricelli, C., Magni, A., & Ventriglia, G. (2020). Not All Pain is Created Equal: Basic Definitions and Diagnostic Work-Up. Pain and therapy, 9(Suppl 1), 1–15. https://doi.org/10.1007/s40122-020-00217-w