Fluid balance Flashcards
what are the mechanism of fluid balance
- baroreceptors
- RAAS
- Vasopressin
- ANP
On average what is the proportion of total body water in an adult
60%
How is the total body water distributed between the intracellular and extracellular compartment
2/3 Intracellular compartment
1/3 extracellular compartment
What is the preoperative evaluation of fluid status
h/o intake and output
blood pressure supine and standing
heart rate
skin
urine output
mental status
What is the significance of orthostatic hypotension?
When SBP decreases of greater than 20 mmHg from supine to standing. It indicates significant fluid loss. heart rate should increase as a compensatory measure. if no increase in heart rate, may indicate autonomic dysfunction or antihypertensive drug therapy
What is the formula for maintenance fluid requirements
- 4-2-1 rule
- insensible losses approximately 1.5ml/kg/hr
NPO deficit calculation
number of hours NPO * maintenance fluid requierement
What is the significance if third space and invisible losses
isotonod trnafer of ECF to from functional body fluid compartments. depends on the type of surgery
Blood loss
we use 1;1 ration
What are tehe types in intravenous fluids we use for rescucitation
- Crystalloids
- Colliods
What is the composition of ringer lactate
Na130, Cl109, K4, Ca3, Lactate 28
What is the composition of Normal Saline, (0.9%)
Na154, Cl154
what are the examples of colloids
Albumin, dextran, hespan
What is the formula for Allowable blood loss
ABL = EBV (HB (INITIAL-HB(FINAL)/HB initial