Visceral Pain
Visceral pain is caused by obstruction, infiltration or compression of visceral structures and supporting
connective tissues.3 Lung, liver and kidney parenchyma are insensitive to pain, but tumours associated with these organs may cause pain when the capsule or adjacent structures are affected.4 Visceral pain is often diffuse and sometimes referred to other nonvisceral structures, making the source of pain difficult to localize.
Neuropathic Pain
Studies indicate approximately 30% to 55% of cancer patients have neuropathic pain, which is due to involvement of neural structures (eg, nerves, plexi or roots), usually by tumour infiltration or compression. Sympathetic activity also plays a role in spontaneous neuropathic pain. This type of pain is characterized as aching, burning, stabbing or lancinating.3,4 It may also present as paraesthesia, dysaesthesia, hyperalgesia or allodynia. Relative to somatic and visceral pain, neuropathic pain responds poorly to systemic opioids, hence other treatments are often utilized. Most post-treatment pain syndromes (eg, postsurgical, postradiotherapy or postchemotherapy pain) are neuropathic.3 Injury to the intercostobrachial nerve during mastectomy causes a tight, burning sensation in the axilla, the medial aspect of the upper arm and the upper aspect of the anterior chest wall. Radiation-induced fibrosis can cause peripheral nerve injury. Vincristine, cisplatin and paclitaxel are neurotoxic and can cause dysaesthesia, paraesthesia, cramps and restless legs associated with weakness, sensory loss or autonomic dysfunction. This set of recommendations aims to provide a logical approach to
effectively manage cancer pain, with a particular focus on neuropathic pain. Patients may have several cancer pain syndromes that respond differently to pharmacological and nonpharmacological interventions. Therefore, a pain management programme should be devised on an individual basis depending upon patient characteristics and responses. Multiple medications may be used, with each agent adjusted according to the specific pain syndrome for which it is used.7 Pain management should be guided by a detailed patient assessment.
Reference source: http://www.neuroPAINhk.org, www.brain-spine.com.hk
The above information is for educations only, if you have any related disease, please consult your neurosurgeon for more information.
