Pain
very complex experience that is personal & subjective, influenced by age, gender & psychosocial factors (social, economic status, race, ethnicity, cultural background)
nociceptors
peripheral nerve fibres that have special endings that can sense different types of harmful stimuli (anything that threatens or damages tissues)
- could be a cut, pressure, heat, inflammation, chemical changes
Nociceptive Pain
In response to tissue damage, nociceptors at the source of the injury relay pain messages in the form of electrical impulses. These pain messages travel along a peripheral nerve to your spinal cord.
What is the difference between fast & slow fibers?
Specialized nerve cells filter and prioritize messages form the peripheral nerves. Severe pain, as from a burn, is processed as an urgent warning, triggering your muscles to pull hand away from the stove. Some pain messages, like a scratch or an upset stomach, are relayed more slowly or with less strength. Pain messages travel to the brain and the brain sends back messages that promote the healing process: Signals ANS to send increased WBCs and platelets for tissue repair. Release of pain-suppressing chemicals.
fast fibres
myelinated fibres that conduct a fast transmission of sensation from peripheral to the CNS for acute severe pain (i.e hand being burned from fire, signalling you to remove hand immediately)
slow fibres
unmyelinated fibres that are responsible for the slow and persistent messaging for less severe pain (dull abdominal pain from needing to expel flatus)
gate control theory
specialized nerve cells in the spinal cord filter and prioritize messages from the peripheral nerves. These nerve cells act like gates controlling which messages get through to the brain and at what speed & strength. Explains that non-painful stimuli close the nerve gates to painful input input which prevents pain sensation from travelling to CNS
4 classifications of pain
somatic
visceral
sympathetic
neuropathic
somatic pain
- musculoskeletal pain (skin, muscles, joints, bones, ligaments)
- Often characterized as a sharp localized pain in a specific area of injury.
- Swelling, cramping & bleeding may exist with somatic pain.
- Responds to a variety of medications: including non-opioids, opioids & nonsteroidal anti-inflammatory drugs.
visceral pain
- pain located within the main body cavity (thorax, abdomen, pelvis)
- due to injury or illness to an internal organ
- The pain receptors in the visceral cavities respond to stretching, swelling & oxygen deprivation.
- Opioids are the most effective pain medication for this classification of pain
- feels like a deep ache with cramping
- Visceral pain may radiate to other locations in the back & chest.
neuropathic pain
- pain that results as a direct consequence of a lesion or disease affecting abnormal functioning of the peripheral nervous system (PNS) or central nervous system (CNS)
- Caused by damage to the nerve cells or changes in the spinal cord processing
- described as burning, freezing, numbing, or tingling
- can also create a “pins and needles” sensation.
- A common form of neuropathic pain occurs when diabetes damages the small nerves in the hands and feet, producing a painful burning sensation
Sympathetic Pain
- Due to possible over-activity of sympathetic nervous system and CNS/PNS mechanisms.
- It controls blood flow to tissues such as skin and muscle, sweating by the skin and the speed and responsiveness of the peripheral nervous system.
- occurs more commonly after fractures & soft tissue injuries of the arms & legs
- Characteristics of sympathetic pain include extreme hypersensitivity in the skin around the injury & peripherally in the limb
- Associated with abnormalities of sweating & temperature control in the area
- The limb is usually so painful, that the sufferer refuses to use it, causing secondary problems after time, such as muscle wasting, joint contractures, & osteoporosis of the bones
What is referred pain?
pain felt in an area from which it has not originated. Due to lack of a dedicated sensory pathway in the brain for info concerning the internal organs
What is referred pain?
pain felt in an area from which it has not originated. Due to lack of a dedicated sensory pathway in the brain for info concerning the internal organs
acute pain
sudden injury that causes trauma to body tissue (cut, burn, accident)
acute pain
sudden injury that causes trauma to body tissue (cut, burn, accident)
S/S of acute pain
- increased heart rate (HR)
- increased respiratory rate (RR)
- increase in blood sugar
- elevated blood pressure (BP)
- diaphoresis - sweating
- pallor or flushing
- decreased gastric acid secretion
- Dilated pupils
- nausea
chronic or persistent pain
- discomfort that last beyond the normal healing period (>3 months)
- pain levels may go fluctuate without any change to an injured area
pharmacological treatment for pain
acetaminophen, opioids, local anaesthetics, NSAIDS, anti-inflammatory drugs, muscle relaxants, antidepressant, antiepileptic
Nursing interventions for pain
- Establishing trusting, therapeutic relationship
- Routine assessments is essential for effective pain management
- Discussing with patient and family what the goals of pain management are - can use the pain scale and use previous pain management strategies and coping skills
- Pharmaceutical vs non-pharmaceutical treatments
- Should be interprofessional care planning
