Pathophys and Assessment of Pain Flashcards
Pain is one of main reasons:
is one of main reasons patients seek care
purpose of rating person’s pain?
assess their level of pain and to determine if interventions are effectively helping that pain or not
-pain has protective function
Somatogenic pain:
nociceptive pain:
neuropathic pain:
pain with usually known cause localized in body tissue
- tissue damage(skin, muscle, bones, joints) and visceral organs
- caused by nerve damage
psychogenic pain
pain for which there is no know physical cause but processing of sensitive information in CNS is disturbed
-psych evaluation will evidence that the pain itself is predominantly sustained by psych factors
Acute pain
a protective mechanism that alerts the individual to a condition or experience that is immediately harmful to the body
Onset……usually sudden
Pain effects on the Respiratory system
Reduction in lung volume (Tidal volume, functional residual capacity, vital capacity)
Regional lung collapse (atelectasis)
Decrease alveolar ventilation leads to hypoxemia and hypercapnia
Cough is decreased
Secretions are retained
Chances of chest infections are increased
Increased O2 consumption
Stimulation of what nervous system occur during acute pain:
Autonomic nervous system; mydriasis(dilated pupils, tachcardia, tachypnea, sweating, vasoconstriction
Inadequate relief of acute pain can contribute to:
hypercoagulability and impaired immunity, leading to such complications as venous thromboembolic disease and infections-like PE
Inadequately controlled acute pain can be a factor in the development of chronic pain, extended hospital stay, readmission, and patient dissatisfaction
Nociceptive pain:
involves the normal neural processing of pain that occurs when free nerve endings are activated by tissue damage or inflammation
Nociceptive involves the 4 processes of :
Transduction
Transmission
Modulation
Perception
Neuropathic pain:
involves the abnormal processing of stimuli from the peripheral or central nervous systems and is thought to serve no useful purpose
Pain stimuli are sense by:
specialized nociceptors that are the nerve terminals of the primary afferent fibers
The pain signal is then transmitted to the dorsal horn of the spinal column and transmitted through the central nervous system (CNS) where it is processed and interpreted in the somatosensory cerebral cortex
The majority of signals are sent contralaterally through:
The spinothalamic tract which synapses in the thalamus
Transduction:
Transmission:
Modulation:
Perception:
- Transduction refers to the conversion of a noxious stimulus (thermal, mechanical, or chemical) into electrical activity in the peripheral terminals of nociceptor sensory fibers
- Transmission refers to the passage of action potentials from the peripheral terminal along axons to the central terminal of nociceptors in the central nervous system. Conduction is the synaptic transfer of input from one neuron to another
- Modulation refers to the alteration (eg, augmentation or suppression) of sensory input
- Perception refers to the “decoding”/interpretation of afferent input in the brain that gives rise to the individual’s specific sensory experience
Nociceptors:
Highly specialized subset of primary sensory neurons that respond only to pain stimuli
Categorized by the kind of stimulation they respond to and the nature of their response
Most noxious stimuli activate a variety of nociceptor types in the affected area. Their signals sum to produce the nociceptive input, leading to the subjective sense of pain
Myelinated nociceptors:
What kind of fibers and what are they responsible for ?
Relatively fast conducting A-delta fibers
Responsible for the first immediate sharp pain
Unmyelinated C fibers:
constitute the majority of peripheral nociceptors
These are slow conducting primary afferents that recover from fatigue more slowly than those of A-delta nociceptors
C fibers mediate delayed and longer-lasting pain, typically characterized as dull
Physiological responses to acute pain may include:
- increased heart rate - diaphoresis
- increased respiratory rate - ↑ blood sugar
- elevated blood pressure - ↓ gastric acid secretion
- pallor or flushing, - ↓ gastric motility
- dilated pupils - ↓ blood flow to the viscera, kidneys, skin
- nausea occasionally
Relief from occurs when:
after the chemical mediators that stimulate the nociceptors are removed
Perception of pain involves:
Perception, the conscious experience of pain, involves both the sensory and affective components of pain
Final Nociceptive process-modulation results from:
activation of the midbrain
Adaptive pain:
contributes to survival by protecting the organism from injury and/or promoting healing when injury has occurred
Maladaptive or chronic pain is:
is pain as disease and represents pathologic functioning of the nervous system
Chronic pain is defined as:
is persistent or intermittent and usually defined as lasting at least 6 months
has been defined as pain which lasts beyond the ordinary duration of time that an insult or injury to the body needs to heal
An argument has been made that the term “persistent pain” should be used in lieu of “chronic pain”
The cause is often unknown
Often develops insidiously
Very often is associated with a sense of hopelessness and helplessness