Nursing the pain and unconsiousness patient

What is pain?

A sensory and/or emotional experience associated with actual or potential tissue damage

what is the pain sensation created by?

a noxious stimulus

what is a noxious stimulus

one that is damaging to tissues

what are examples of noxious stimulus

thermal, mechanical and chemical

what is meant by thermal (noxious stimulus)

high and low temperatures

what is meant by mechanical (noxious stimulus)

pressure, swelling, cutting type injury

what is meant by chemical (noxious stimulus)

natural chemicals released from damaged cells by inflammation or external chemical exposure

what is nociception?

is the perception of pain detected in nociceptive pathways transmitted to the central nervous system

what are the 3 categories pain is recognised in?

physiological, inflammatory and neuropathic

what is physiological pain?

An early warning device that alerts the animal to the presence of potentially damaging stimuli in the environment

The pain is appropriate to the degree of stimulation and stops when the stimulation stops and pain is localised

what is inflammatory pain?

Clinical pain initiated by tissue damage and inflammation as a result of surgery or trauma

Heightened pain sensitivity as a result of changes in pain pathways

what is neuropathic pain

clinical pain initiated by damage to the nervous system itself

can occur following amputation of a limb

how is pain broadly categorised into types

1. somatic pain

2. visceral pain

3. neuropathic pain

4. idiopathic pain

what is somatic pain?

pain originating from the skin, muscles, bones or joints. This pain is usually described as sharp or throbbing. Common in soft tissue or fracture injuries

what is visceral pain?

associated with internal organs, this pain is more diffuse and difficult to localise. It may be deep, aching discomfort and often observed in conditions such as pancreatitis or gastrointestinal disorders

What is neuropathic pain?

Pain irising from nerve damage or irritation, this pain is often described as burning or tingling. It can be challenging to manage and frequently occurs with conditions such as intervertebral disc disease or spinal cord injury

what is idiopathic pain

chronic pain that has no identifible underlying cause, which can be challenging for both veterinary professionals and owners. Management typically involves a comprehensive, multimodal approach

what are nociceptors?

nerve endings

what do nerve endings detect?

sensory input when tissues are damaged

what is the pain pathway?

1. transduction

2. transmission

3. modulation

4. a spinal reflex

5. perception of pain at brain

what occurs at transduction

they convert the chemical/mechanical/thermal energy at the site of injury into electrical activity that the nervous system can understand

what occurs at transmission

electrical signals is transmitted to the dorsal horn of the spinal cord and onto the brain

what occurs at modulation

involves the changing, inhibiting or amplifying of the transmission impulses within the spinal cord

when can a spinal cord reflex occur immediately ie what is needed

a motor response

where and how does perception of pain occur

in the brain upon the recognition of the sensory input

what does pain create

a stress response

what does the sympathetic nervous system release?

catecholamines (adrenaline)

what is the result of the release of catecholamines (adrenaline)

1. tachycardia

2. increased cardiac output

3. tachypnoea

4. increased blood pressure increased intestinal secretions

5. urine retention

6. increased metabolism and oxygen

7. reduced efficiency of immune system

8. increased sensitivity to pain

what does the activation of the parasympathetic nervous system release

acetylocholine

what does the release of acetylcholine result in?

1. bradycardia

2. hypotension

3. syncope

4. nausea

what does pain trigger the release of

stress hormones; cortisol and catecholamines

what are the levels of consciousness?

1. alert

2. obtunded

3. stuporous

4. coma