Exam 2: 17 Feb Pain Flashcards
What is the annual cost of pain management?
$40 billion
This figure does not include costs associated with surgery and lost workdays.
What role does the dorsal root ganglion play in pain modulation?
It acts as a peripheral relay station for pain signals to the spinal cord
The dorsal root ganglion is crucial for transmitting pain stimuli.
What are the four main steps in the pain pathway?
- Transduction
- Transmission
- Modulation
- Perception
Each step plays a critical role in how pain is experienced.
Which part of the brain interprets pain signals?
The thalamus
The thalamus relays signals to the primary somatosensory cortex for pain interpretation.
What types of fibers are involved in pain transmission?
- Unmyelinated C fibers
- Myelinated A fibers
C fibers are slow, while A fibers transmit pain signals quickly.
What is the function of local anesthetics in pain management?
They stop pain transmission at the transduction level
Local anesthetics block pain signals before they reach the spinal cord.
What is the difference between acute and chronic pain?
- Acute pain usually resolves after the underlying cause is treated. (Occurs days to weeks after injury.)
- Chronic pain persists beyond tissue healing (lasting more than 3 to 6 months)
What are hyperalgesia and allodynia?
- Hyperalgesia: increased sensitivity to pain
- Allodynia: pain from stimuli that do not normally provoke pain
Both are conditions related to abnormal pain perception.
Where does the modulation of pain impulses occur?
The dorsal horn of the spinal cord
Modulation can inhibit or excite pain transmission.
What systemic responses can occur due to pain?
- Cardiovascular: hypertension, tachycardia
- Pulmonary: increased oxygen consumption
- Gastrointestinal: decreased motility
- Endocrine: increased cortisol levels
Each response can lead to further complications if pain is not managed.
What is the gate control theory of pain?
It describes how the spinal dorsal horn acts as a neurologic gate for pain transmission
This theory explains how certain stimuli can inhibit pain signals.
What role do neuromodulators play in pain transmission?
- Substance P
- Glutamate
These are key chemicals involved in the pain signaling process.
What are the four ascending pathways of pain interpretation?
- Spinothalamic
- Spinal medullary
- Spinal bulbocaudal
- Spinal hypothalamic
Each pathway contributes to the overall perception of pain.
True or False: The emotional response to pain includes anxiety and depression.
True
Emotional responses can complicate pain management and recovery.
Fill in the blank: The _______ is responsible for modulating pain signals in the brainstem.
periaqueductal gray (PAG)
The PAG is involved in descending inhibitory pathways.
What complications can arise from the cardiovascular response to pain?
- Myocardial ischemia
- Increased myocardial irritability
These complications are serious and require careful pain management.
What is the resting threshold of pain receptors?
It is the level at which pain receptors begin to transmit impulses
Pain impulses occur once this threshold is surpassed.
What types of stimuli can type one (myelinated) fibers transmit?
- Heat
- Mechanical
- Chemical
What are some chemical mediators involved in pain transmission?
- Substance P
- Calcitonin
- Bradykinin
- Calcitonin gene-related peptide
What role do prostaglandins, thromboxanes, and endocannabinoids play in pain?
They cause vasodilation and inflammation
What medications are commonly used to address chemical mediators?
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Cannabis
What is hyperalgesia?
Increased pain sensation to normal stimuli
What is allodynia?
Perception of pain in response to normally non-painful stimuli
What is primary hyperalgesia?
Increased pain sensation at the original site of injury
What is secondary hyperalgesia?
Sensitization of uninjured skin surrounding the injury
What structure in the spinal cord is responsible for relating pain signals?
Dorsal horn
What are the laminae involved in pain modulation in the spinal cord?
- Lamina 1 (marginal layer)
- Lamina 2 (substantia gelatinosa)
- I,IV, & VII, along with the ventral horn innervate the muscle and viscera
- III & IV utilize NKI receptors with Substance P
What is the significance of lamina 2 in pain modulation?
It is where opioids work to inhibit pain transmission
What is the gate control theory of pain?
A theory that describes how pain transmission can be modulated in the spinal cord
How does the gate control theory explain the effect of massage therapy on pain?
Massage can close the gate to pain transmission, reducing the perception of pain
What is the role of glutamate in pain modulation?
It is an excitatory impulse mediator
Which substances are considered inhibitory impulse mediators?
- GABA
- Glycine
- Norepinephrine
What are the four ascending pathways for pain interpretation?
- Spinothalamic
- Spinal medullary
- Spinal bullbar
- Spinal hypothalamic
What brain regions are involved in the perception of pain?
- Somatosensory cortex
- Anterior cingulate cortex
- Insular cortex
- Prefrontal cortex
What is the function of descending inhibitory pathways in pain perception?
They can inhibit the interpretation of pain signals
What can influence the perception of a paper cut as painful or not?
Individual interpretation can vary based on context and emotional state
What is the descending inhibitory tract?
A pathway that modulates pain transmission, originating from the periaqueductal gray (PAG) and rostral ventral medulla (RVM)
It reduces pain perception by affecting neurotransmitters at the spinal level.
What is the role of endorphins in pain modulation?
They are released during the experience of pain and contribute to the inhibitory pathway, leading to reduced pain perception
Endorphins, enkephalins, and serotonin are examples of neurotransmitters involved in this process.
What neurotransmitter is known as an excitatory pain transmitter?
Substance P
It plays a key role in the transmission of pain signals in the nervous system.
Fill in the blank: The process that hyperpolarizes A delta and C fibers involves the release of _______.
neurotransmitters
This process decreases the release of substance P, contributing to pain inhibition.
What are the key differences between acute and chronic pain?
Acute pain lasts days to weeks; chronic pain persists for months, often beyond tissue healing
Chronic pain can lead to ongoing discomfort despite no tissue injury.
What is neuropathic pain?
Pain that persists after tissue healing, often characterized by allodynia or hyperalgesia
It can be exacerbated in cancer patients due to chemotherapy.
True or False: Visceral pain is well localized.
False
Visceral pain is often diffused and poorly localized.
What is Complex Regional Pain Syndrome (CRPS)?
A variety of painful conditions following an injury, characterized by sensory and motor impairments
Symptoms include spontaneous pain, allodynia, and local tissue changes.
At what gestational week can neonates perceive pain?
23 weeks of gestation
Neonates have a lower pain threshold and exaggerated pain responses.
What are the cardiovascular responses to pain?
Hypertension, tachycardia, myocardial irritability, and decreased cardiac output
These responses can lead to myocardial ischemia.
Fill in the blank: Pain can lead to impaired _______ function, contributing to respiratory complications.
cough
Impaired coughing can lead to pneumonia or respiratory infections.
How does pain affect gastrointestinal function?
It enhances sympathetic tone, leading to decreased motility and potential for ileus
Pain management is crucial to prevent complications such as constipation.
What hormonal changes occur in response to pain?
Increase in catabolic hormones (e.g., cortisol) and decrease in anabolic hormones
This leads to increased glucose levels and negative nitrogen balance.
What is the effect of pain on coagulation?
Increased coagulability and risk of venous thromboembolic disease (VTE)
Pain can lead to platelet adhesiveness and reduced fibrinolysis.
What emotional responses can be induced by pain?
Anxiety, sleep disturbances, and depression
These responses can further complicate pain management.
What is the significance of the reticular activating system in pain perception?
It can influence the experience of pain and is affected by factors such as lack of sleep and stress
This system plays a role in modulating the pain experience.
