Pain Medication

Question 1

What are sources of pain?

Answer 1

Trauma
Inflammation
Ischemia 
Neuropathic
Chronic
Malignant Pain

Question 2

What pathway does pain follow when we are exposed to trauma?

Answer 2

Trauma pain is of neuronal origin where stimuli follows delta fibres which makes for fast pain.

Question 3

What pathway does pain travel when stimulated by ischaemia/inflammation?

Answer 3

Is of chemical origin stimulated by prostaglandins or histamine. Travels along C fibres which relates to delayed pain.

Question 4

Describe the gate control theory of pain?

Answer 4

The gate control theory of pain asserts that non-painful input closes the “gates” to painful input, which prevents pain sensation from traveling to the central nervous system. Therefore, stimulation by non-noxious input is able to suppress pain.

Question 5

What stimuli can close the gate in the gate control theory of pain?

Answer 5

Peripheral nerve stimulation
– (Rubbing)
Neurohumoral influences (mental state)
– Dynorphins
– Enkephalins
– Endorphins

Question 6

What are the signs of inflammation?

Answer 6

Redness (Rubor)
Hear (calor)
Swelling (tumor)
Pain (dolor)

Loss of function

Question 7

What changes occur to vascular permeability in acute inflammation?

Answer 7

Vascular permeability increases

Therefore slowing of circulation and plasma proteins pull more fluid out of the blood vessels to cause odema.

Question 8

Define oedema.

Answer 8

a condition characterized by an excess of watery fluid collecting in the cavities or tissues of the body.

Question 9

How is an abscess formed?

Answer 9

When foreign organisms such as bacteria enter the body, the immune system sends white blood cells to fight the infection. This causes swelling (inflammation) at the site of infection and the death of nearby tissue, creating a hole called a cavity, which fills with pus to form an abscess

Question 9

Define allodynia.

Answer 9

A pain due to a stimulus which does not normally provoke pain. Temperature or physical stimuli can provoke allodynia, which may feel like a burning sensation, and it often occurs after injury to a site.

Question 10

What role do Leukocytes play in acute inflammation ?

Answer 10

• Migration
• Adhesion
• Emigration towards a chemotactic stmuli
• Phagocytosis
• Extracellular release of leukocyte product

Question 11

What are the consequences to oxygen deprivation in energy production?

Answer 11

Anaerobic respiration occurs and lactic acid formation occurs

Question 12

Define acute pain.

Answer 12

Less then 3 months and is a response to a natural/therapeutic process or traumatic injury.

Question 13

Define chronic pain.

Answer 13

> 3 months

Question 14

What are the types of pain relief?

Answer 14

Local anaesthetics
Opioids
Non opioid
Anti Ischaemia

Question 15

How do local anaesthetics work?

Answer 15

Sodium channel blocker as it blocks the sodium receptor which stops the depolarisation of the action potential.

Question 16

What are the adverse effects of the local aesthetics?

Answer 16

Neurological disorders
 - Convulsion
 - Restlessness
 - Respiratory paralysis
Cardiac disorders
- Reduced impulse conduction in the hear
 - (Cardiac arrest)

Question 17

What are the different types of nerve block?

Answer 17

Topical block
Peripheral block
Infiltration
Epidural block

Question 18

Define hyperpolarise.

Answer 18

Cell is made more negative via potassium effluent from cell. This is the mechanism of action for opioids as the cell stops firing.

Question 19

What binds to opioid receptors?

Answer 19

Endogenous:
 - Hormone e.g. endorphins
 - Neuronal 
Exogenous:
 - Morphine

Question 20

What are the side effects of opioids?

Answer 20

Cough centre depression
Pupil constriction
Diaphoresis
Euphoria
Flushing
Respiratory rate and rhythm depression!!!
Bronchial contraction
Vasodilation
Biliary spasm
Decreased peristalsis!!! Constipation!!
Increases bladder tone

Question 21

What are the types of opioids?

Answer 21

Morphine
Codeine
Pethidine
Tramadol

Question 22

What is COX 1?

Answer 22

Is an enzyme that produces chemicals that protect the stomach lining, reduces acid secretion in the stomach & increases epithelial blood flow to the intestines.

Question 23

What is COX 2?

Answer 23

Is an enzyme that is produced by tissue damage that produces chemicals that provide inflammatory response.

Question 24

What are the side effects of NSAIDs?

Answer 24

Gastric Irritation
Broncho-spasm
Renal damage
Inhibits ovulation
Hypersensitivity

Question 25

What are side effects of COX 2 inhibitors?

Answer 25

Cardiac so rarely given

Question 26

What are the adverse side effects of NSAIDS?

Answer 26

Gastric Irritation
Broncho-spasm
Renal damage
Inhibits ovulation
Hypersensitivity

Question 27

What are the aims anti-ischaemic treatment?

Answer 27

Improve blood flow
Reduce muscle oxygen utilisation
Stop spasm

Question 29

Name examples of spasmodic pain.

Answer 29

Renal colic
Stomach cramps
Dysmenorrhoea

Question 30

What is the mechanism in anti spasmodic drugs?

Answer 30

Act as anticholinergics such as Buscopan, that reduce visceral muscle contraction which relieves pain.

Question 31

What are the cautions for taking anti spasmodics?

Answer 31

• Previous sensitivity/ allergic
• Glaucoma
• Blockage of urinary tract
• Severe ulcerative colitis
• Reflux oesophagitis

Question 32

What are causes of ischaemic pain?

Answer 32

• Spasm
• Blocked/narrowed blood vessels
• Accumulation of waste products/ cytokines

Question 33

What are acute adverse effects of opiods?

Answer 33

Respiratory depression

Vascular smooth muscle vasodilation (Hypotension)

Question 34

Name some examples of NSAIDs.

Answer 34

Paracetamol
Aspirin
Fenamates (Diclofenac)
Indomethacin
Ibuprofen

Question 35

What are the adverse effects of anti spasmodics?

Answer 35

dizziness
drowsiness
light-headedness
nausea
blurred vision
dry mouth
weakness

Question 36

What is pain transduced by?

Answer 36

As pain does not have a particular receptor, it is picked up by free nerve endings that are sensitive to different painful stimuli

Question 37

What nerves are found when pain was transmitting pain to the dorsal horn of the spinal cord?

Answer 37

• Fast conducting delta nerves

- Slow conducting C nerve fibres

Question 38

What pathway takes the brain signal up to the brain?

Answer 38

Spino-thalamic tract

Question 39

How does morphine work?

Answer 39

Morphine works as an agonist on the Mu receptor, inhibiting pain

Question 40

Why does draining an abscess relieve pain?

Answer 40

It reduces the pressure in the wound.

Question 41

How do the cardinal signs of inflammation are caused?

Answer 41

The cardinal signs of inflammation may be explained by an increased blood flow and capillaries with increased permeability. This would lead to an increased blood flow (redness & heat) and increased formation of odema Swelling). When the pressure increases in the area inflammatory mediator-derived allodynia causes the small increase in pressure painful. The resulting pain frequently causes a loss of function of the inflamed part of the body.

Question 42

Which enzyme is frequently inhibited with non-opiod pain relief?

Answer 42

Cycloxygenase Enzyme

Question 43

What happens to WBC (leukocytes) when injury occurs?

Answer 43

White blood cells (leukocytes) are directed towards the injured area due to chemotaxis. To gain access to the injured tissue the WBCs, first marginate from the blood stream and then adhere to the endothelium. This causes the endothelial cells to loosen their junctions and move apart so that the WBC can emigrate into the area of damage and engulf or phagocytose the dead cells or debris.