Fluids Flashcards
Water percentages
The amount of water as a percentage within a person decreases with age;
- Newborn; 75% of water
- Average adult; 60% roughly
- Older adult; between 45% & 50%
Fluid compartments
- Extracellular fluid (ECF)
- comprises of the fluid between the cells and is also known as interstitial or tissue fluid. it is the plasma (fluid) of the blood and lymph
- Intracellular Fluid (ICF)
- present within all body cells
This is; two thirds ICF & one third ECF in adults, with the opposite in children.
Four ways fluids are excreted from the body/ Sensible & insensible fluid losses
Urine via the bladder
Sweat via the skin
Air via the lungs
Faeces via the bowels
Sensible losses;
- this refers to the typical routes of excretion such as urination and defecation
Insensible losses;
- other routes of fluid loss, such as through the skin via sweat and air via the respiratory tract
Groups most at risk of fluid depletion
- elderly
- children
- those with mobility concerns
- those in a hotter climate
- those with LDs
- those with dementia
- unconscious patients
- those with mental health problems
Typical volumes of drinking vessels
- mug- 20mL
- carton- 240mL
- jug-800mL
- can- 330mL
- water bottle- 330mL
- glass- 250mL
- plastic cup- 150/175mL
- soup bowl- 400mLs (dependends)
Fluid balance and physiological parameter recordings
- Blood pressure
- dehydration can result in low blood volume and therefore low blood pressure (less blood to force against the blood vessel walls)
- in severe situations of dehydration, this drop in BP may only be apparent during positional BP readings, showing as postural hypotension when standing from sitting.
- fluid overload such as during IV therapy can cause an increased BP
Pulse
- an increased in pulse rate occurs in fluid volume deficit because there is less fluid in the vascular system (hypovolemia), causing the heart to work harder.
-fluid volume excess also causes a raised pulse, and so adequate monitoring of fluid input and output is vital
Respiration
- the RR, effort and depth can change in response to fluid, electrolyte and acid-base imbalance. E.g. a person with fluid volume excess can develop pulmonary oedema which causes dysnopea; difficulty breathing and a cough with frothy sputum
-dehydration can also cause mucus to become thicker and stickier, making breathing harder and more likely to become ill
What are diuretics
Also known as water pills, these can help rid the body of salt (sodium) and water. It is any substance that promotes diuresis; the increased production of urine, with all increasing the excretion of water from the body via the kidneys.
They can also be used to treat the following;
- heart failure
- hypertension
- increased excretion from the body
Furosemide is a type of diuretic that blocks the effects of ADH and therefore increases urine volume