Pain Flashcards
What is pain?
Unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.
What is nocireceptive pain?
Pathological process arising from somatic or visceral nociceptors.
What is neuropathic pain?
The abnormal functioning of the somatosensory nervous system.
What is psychogenic pain?
This pain has psychological, psycho-social or psychiatric origin.
Explain the difference between chronic and acute pain?
Chronic pain is usually persistent and lasts longer than 3 months -may be due to illnesses and it difficult to treat. Treated with paracetamol and opioids, dull, aching, can have a profound social effect.
Acute pain - related to injury and is sudden in onset - normally can be treated. Treated with opioids, sudden onset, sharp and localised.
How does the inflammatory process affect the pain receptors?
The chemical mediators (prostaglandin / histamines) and the mechanical pressure of the oedema will stimulate the nociceptors.
In the inflammatory process, increased capillary permeability results in what response?
Pain and swelling.
In the inflammatory process, arteriolar dilation results in what response?
Heat and redness.
The sensory pathway consists of 3 neurons. What are they and where do they start?
First / second and third neuron.
Starting from the place where sensory is recieved to the brain.
Where does the first neuron originate and what type of receptors does it have?
Originates in PNS - afferent neuron and comes from the site of origin of the sensation (skin / organ).
The receptors (thermo / chemo / nocio) on the dendrites of these neurons must be stimulated to generate an electrical impulse.
Where does the second neuron originate and what is its function?
Located in spinal cord - multipoplar neuron.
The axon of this neuron crosses to the opposite side of the body - this may be at the level where the neuron enters the spinal cord or medulla.
Where is the third neuron and what its function?
Radiates from the thalamus to the sensory cortex and other relevant areas of the brain.
What is transduction in the pain pathway?
The conversion of one type of stimuli or energy into another form. In the pain pathway a chemical trigger is changed into an electrical impulse.
In the pain pathway, the damaged body cells release chemicals into the interstitial fluid. One is a prostaglandins, what are four others?
Histamines
Bradykinins
Potassium
Nitric oxide
True or false. The pain threshold does not vary much between people, it is the physiological component of pain.
True.
What is pain transmission?
It is the electrical impulse conduction along the pain pathway from the site to the brain.
In the sequence of first, second and third neurons. What role does the thalamus play?
The 2nd neuron synapses with the 3rd neuron in the thalamus. From here it radiates from the thalamus to the sensory cortex and other areas for processing and perception.
Also, it is involved in basic interpretation of pain.
In the pain pathway, define perception of pain?
Refers to the processing and interpreting of the information. It can involve multiple neurons and many association areas in the brain.
In what part of the brain does the identification of the source and location of the pain occur?
In the sensory cortex of the cerebrum.
What is the sensory-discriminative dimension of the pain pathway?
Determines the severity of the pain occurs in the sensory cortex and reticular activating system.
True or false. The affective motivation component is the reference to the meaning and emotional component. This occurs in the limbic system and amygdala.
True.
What is the difference between pain tolerance and pain threshold?
Pain tolerance is the point at which pain becomes unbearable to the person - is subjective and varies widely among individuals. Pain tolerance can be affected by ethnicity, genetics, gender and culture.
Pain threshold is the point at which the pain pathway is initiated by tissue damage and does not vary much between different people.
What is pain modulation?
The bodies normal response of modifying the pain perception. This can involve a variety of processes, - altering the transmission or perception process.
Gate theory (which is used in massage therapy) is one example of modulation. What are two others?
CNS depression - endogenous modulators
Descending inhibitory pathways are activated in hypnosis or TENS or morphine administration.
Gate therapy - massage therapy or TENS (trans cutaneous electrical nerve simulation (or acupuncture).
How can we assess pain in a clinical environment?
Numeric pain scale
PQRSTU - provocative or palliative / quality or quantity / region or radiation / severity / timing or treatment / understanding
OLDCART - Onset (acute or gradual) / location / duration / characteristics / aggravating factors / relieving factors / treatments (response) / severity
What are some associated sights and symptoms of pain?
Tachycardia / hypertension / hyperventilation / nausea / vomiting / fear / anxiety.
What does the abbreviation 5-HT stand for?
serotonin
How many neurons does the ascending pathway consist of?
Three.
With which of the sensory neurons does the the descending pathway synapse?
2nd -spinal
Can the mechanoreceptor fibres and nociceptor fibres transmit impulse to the spinal cord fibres at the same time?
No - which ever nerve impulse gets there first, will inhibit the other.
What is the role of nor-adrenaline and opiates at the synapse between primary and secondary sensory neurons?
Both inhibit pain transmission = modulation of pain.
Can we use pethidine for treating a cough or diarrhoea?
No
