haemo exam revision Flashcards
What are three components of body fluids?
- Water
- Electrolytes
- Non-electrolytes
what is fluid as a percentage of body weight.
60% male
50% female
Infants 70-80%
Elderly 45%
Name the main intracellular and extracellular ions
- Intracellular = potassium
- Extracellular = sodium
What are the three areas within the extracellular fluid compartment?
- Intravascular
- Interstitial
*Transcellular
Describe third spacing
- Represents the loss or trapping of ECF in transcellular spaces
Give three examples of transcellular spaces
- CSF
- Peritoneal space –aka ascites
- Pleural space
- Pericardial cavities
- Joint spaces
- GI tract
What three interrelated processes do volume, solutes and pH balance within the body rely on?
- Fluid balance
- Electrolyte balance
- Acid base balance
Name three functions of electrolytes
- Regulate essential mineral and enzymes
- Control osmosis of water between body compartments
- Maintain acid/base balance required for normal cellular activities
- Create action potentials for neurotransmission
Describe the difference between electrolytes and non-electrolytes
Electrolytes are charged ions that dissolve in water. Non-electrolyte are compounds with
Describe the difference between simple diffusion and facilitated diffusion
- Facilitated diffusion is where the solute is attached to a lipid-soluble membrane carrier protein which facilitates the transport through what would otherwise be an impermeable membrane
Describe active transport
- Moves solutes against an osmotic gradient by using the sodium/potassium pump
What is the normal pH range of the human body?
7.35-7.45
Name two effects the change in pH has at a cellular level?
Disrupts the stability of the cell membranes
Alters protein structure
Name three different types of chemical buffer systems
- Phosphate, protein, bicarbonate
What are the two general causes of oedema?
- Abnormal leakage of fluid from the plasma to the interstitial spaces across the capillaries
- Failure of the lymphatic system to return fluid from the interstitium back to the intravascular space
Define osmolality
The concentration of a solution expressed as the total number of solute particles per kilogram (within the body
Name the four forces that contribute to Starlings equilibrium.
- Blood hydrostatic pressure (BHP)
- Blood (colloidal) osmotic pressure (BOP)
- Interstitial hydrostatic pressure (IHP)
- Interstitial (colloidal) osmotic pressure (IOP)
What does blood (colloidal) osmotic pressure do in the capillary?
Pulls fluid back into the capillary from the interstitial compartment As fluid moves in and out of the capillaries there is a small amount of excess fluid.
What system removes this and returns it to the circulation?
Lymphatic system
Describe what is meant by the 3:1 rule in association with blood loss and
fluid resuscitation
Infuse 300mL of crystalloid for every 100mL of blood lost to achieve fluid resuscitation
How much of the infused fluid will still be in the vascular space 1 hour post administration?
One third
Define the term colloid
A substance made up of larger particles that are unable to pass through the capillary membrane and thus remain in the intravascular space. The particles can be large molecules like proteins.
Name three different types of fluids can be used for volume resuscitation?
Isotonic crystalloids
Hypertonic crystalloids
Synthetic colloids
Blood substitutes
What is the name of the receptors that receive pain stimulation?
Nociceptors.