Perioperative Pain management

Question 1

What is Pain?

Answer 1

An unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.

Question 2

Classifications: Duration

Answer 2

ACUTE:
Recent onset
Short duration (<6 weeks)
Acute pain is associated with trauma, surgery or acute illness.
Usually limited to the area of damage
Usually resolves with healing.
CHRONIC
Pain that is no longer associated with normal tissue healing processes
Persists beyond the usual course of an acute illness or injury or beyond normal tissue healing times

Question 3

Classification: Site of injury (Nociceptive pain)

Answer 3

Pain that arises from actual or threatened damage to non-neural tissue and is due to the activation of nociceptors.

Nociception: The neural process of encoding noxious stimuli

Quality:
(Somatic) Sharp, dull, aching, throbbing.
(Visceral)
Gnawing, squeezing, cramping
Localisation:
(Somatic) Localised
(Visceral) Diffuse, poorly localised, refferred pain.

Question 4

Classification: Site of injury (Neuropathic pain)

Answer 4

Pain caused by a lesion or disease of the somatosensory nervous system.

Quality:
Burning, electric shocks, allodynia
Localisation:
Dermatomal or diffuse
Associated symptoms:
Tingling, pins and needles, numbness, itching

Question 5

Classification: Site of injury (Nociplastic pain)

Answer 5

Pain that arises from altered nociception despite no clear evidence of actual or threatened tissue damage causing the activation of peripheral nociceptors or evidence for disease or lesion of the somatosensory system causing the pain.

Question 6

PAIN MANAGEMENT:

Answer 6

Simple analgesia:
Paracetamol
NSAIDS & COX 2 inhibitors:
Ibuprofen
Diclofenac
Ketorola
Indomethacinc

Question 7

NSAIDS & COX 2 inhibitors:

Answer 7

AFFECT COX2 TO PREVENT INFLAMMATION & PAIN however it may cause bronchospasm because the accumulating Arachidonic Acid becomes leukotrienes

Ibuprofen
Diclofenac
Ketorola
Indomethacinc
Parecox b

Side effects:
Gastric irritation
Renal dysfunction
Platelet dysfunction
Bronchospasm
Hepatotoxicity
Myocardial Infarction

Question 8

Opioids “MIS BRUNCH’

Answer 8

Weak opioids: codeine, tramadol
Strong opioids:
Long acting: morphine
Short acting: fentanyl, remifentanil, sufentanyl & alfentanyl

Side Effects
Muscle rigidity, Itchiness/pruritis, Sedation, Bradycardia, Respiratory Distress, Urinary Retention, Nausea and Vomiting,
Constipation
Histamine release

Question 9

Naloxone “PHAA”

Answer 9

Opioids antagonist
1-4mcg/kg IV
Rapidly displaces opioids from receptors
Useful for emergency management of respiratory depression
Neonates: opioid reversal in mothers who have received opioids in labour or as part of GA pre-delivery
Diagnostic value
NOT A CURE—patient must be carefully monitored as opioids can bind again
Sudden opioid withdrawal can be extremely distressing for the patient

Side effects include:
Arrythmias
Pulmonary oedema
Hypertension
Anti-analgesic

Question 10

What is allodynia?

Answer 10

Pain due to a stimulus that does not normally provoke pain.

Question 11

What is hyperalgesia?

Answer 11

Increased pain from a stimulus that normally provokes pain