Fluid therapy Flashcards
Crystalloid
Contains small molecules
isotonic crystalloid purpose
To manage dehydration and hypovolaemia
isotonic crystalloid examples
Hartmanns, 0.9% NaCl
Colloid
contains large molecules that can’t cross semi-perm membranes
5 routes of fluid admin
Per os (mouth)
sub cut
IV
central venous access
IO
Volume overload symptoms (hypervolaemia)
dyspnoea, tachypnoea, crackles
Venous engorgement symptoms
jugular distension, peripheral oedema, cavitary effusions
fluid distribution
60% is water- 55% extravascular- 40% inside cells, 15% outside cells
hypovolaemia vs dehydration
hypovolaemia is fluid lost quickly from the intravascular space, dehydration is fluid lost slowly from extravascular space
consequences of hypovolaemia
blood loss-> reduced preload-> reduced stroke volume-> decreased CO-> vasoconstriction and tachycardia-> BP drop
patient assessment of IV volume
HR
pulse quality
MM colour
CRT (>2secs)
BP
mentation (mental status)
temp
patient assessment of extravascular volume
moistness of MM
skin turgor
weight
globe position
urine output
clinicopathological parameters
PCV, TS
urea, creatinine
USG
shock
an imbalance between oxygen delivery to the tissues and oxygen consumption by the tissues
4 types of shock
hypovolaemia
cardiogenic
obstructive (tension pneumothorax, thromboembolism)
distributive (uncontrolled inflammatory response)
physiological response to hypovolaemic shock
neurohormonal response:
- catecholamine release (increases HR, vasoconstriction)
- activation of renin-angiotension-aldosterone system (increases Na + water retention
- ADH release
- spleen contraction (releases more RBC)