Fluid therapy Flashcards
What ways do we lose fluid?
Urine
Faeces/diarrhoea
Vomit
Blood loss
Third space loss
Inflammatory exudate
Insensible losses
Redistriubtion
Explain fluid loss via vomiting
Loss of acid (HCl) => metabolic alkalosis
Explain fluid loss via blood loss
Can be external or internal e.g., bleeding splenic haemangiosarcoma (tumour)
Loss of blood => loss of O2 supply => anareobic respiration => lactic acid formation => acidosis
Describe fluid loss via third space loss
Third space = body cavities e.g., abdomen
Fluid can be a transudate (low protein and cells), modified transudate (high protein, low cells) or exudate (high protein and cells) depending on disease
Loss of fluid +/- proteins => reduced blood volume => poor oxygen supply => anaerobic respiration => lactic acid formation => acidosis
Explain fluid loss via inflammatory exudate
Loss of fluid due to inflammation e.g., burns
Burns lead to fluid and protein loss from site
Explain fluid loss via insensible losses
e.g., sweating, breathing
can be significant e.g., sweating in exercising horses
Explain fluid loss via redistribution
a relative loss
Relates to hypovolaemia and distributive shock
In ‘distributive’ disease blood vessels dilate => more fluid needed to fill vessels back up
Peripheral vasodilation causes a relative hypovolaemia due to change in capacticance
Define dehydration
Loss of fluid from intracellular and interstitial compartments
Define hypovolaemia
loss of fluid from intravascular space
How can you check for hypovolaemia?
poor Pulse quality
pale Mucous membrane
long CRT
high Heart rate
low rectal temp
Blood parameters
What are the clinical signs of dehydration?
Prolonged skin tent
Tacky or dry mucous membranes
Sunken and dull eyes
Weight loss
what is shock?
Tissue hypoxia (low oxygen) due to:
- reduced O2 delivery
- excessive O2 demand/usage
- inadequate utilisation of O2
What are the 4 types of shock causing reduced delivery?
Hypovolaemic:
- e.g. haemorrhagic
- BP drops => reduced perfusion of tissues
Distributive:
- vasodilation => reduced ability of blood to fill vessels => reduced BP => reduced perfusion of tissues
Cardiogenic:
- ‘pump’ no longer working effectively => reduced BP => reduced perfusion of tissue
Obstructive:
- BV blocked or compressed so blood cannot reach tissues
How can you diagnose hypovolaemic shock?
same as hypovolaemia:
poor Pulse quality
pale Mucous membrane
long CRT
high Heart rate
low rectal temp
Blood parameters
How can distributive shock be diagnosed?
Dark pink/red mucous membranes
Quick capillary time
Normal or high temp
Reduced BP:
- weak pulse
