A.1 Flashcards
what determines distribution of water between IC and EC?
And what distributes the water between IC and EC?
Osmotic equilibrium and onconit pressure desides
Na+ K+ Cl- distributes
hormone increasing water reabsorption in kidneys?
ADH
normal plasma osmolarity?
280mOsm/L
daily requirements of Na
1,5-2,5 mmol/kg
max Na C kidney can handle
> 1500 mOSm/kg in healthy
600-800 mOsm/kg in ICU patients
what happens to renal perfusion pressure in ICU patiens?
In healthy individuals without systemic hypertension, intrarenal blood flow is auto-regulated at renal perfusion pressures between 60 and 100 mmHg. During critical illness, these processes may be compromised.
How does pressure affect filtration rate in the kidneys?
The glomerular filtration rate is directly proportional to the pressure gradient in the glomerulus, so changes in pressure will change GFR. GFR is also an indicator of urine production, increased GFR will increase urine production, and vice versa
mechanical ventilation effect on kidneys?
increase renal perfusion pressure by increasing preload on the heart
what effect does hyperthermia have on fluid loss`
increases insensible (skin, lung) fluid loss with 2,5 L/day
what effect does hyperventilation have on fluid loss`
increase insensible fluid loss by 0,5-2 L/day
what effect does tracheostomy have on fluid loss`
increase insensible fluid loss by 0,7 L/day
hypovolemia can cause
*Decreased tissue perfusion
*Tissue hypoxia
*Anaerob metabolism
*Inflammatory cascade↑
*Neutrophil oxidative killing↓
*Wound healing disorder
*Organ dysfunction
hypervolemia can cause
*Oedema
*Anastomosis insufficiency
*Bowel dysfunction, PONV
*Coagulation disorder
*Renal insufficiency
*Cardiopulm. complications
*Organ dysfunction
fluid compartments in the body
─ Intracellular fluid (ICF): 40% of body weight
─ Extracellular fluid (ECF): 20% of body weight
─ Interstitial fluid: 15% of body weight
─ Intravascular fluid: 5% of body weight
how can you increase Preload?
Colloid and Crystaloid solutions
how can you decrease Preload?
diuretics
How to measure CVP?
in SVC and tells us what the preload is
3 methods of measuring SV
PICCO
Swan-Gaz catheter
Echochardiography
best way to measure fluid responsivness?
measuring SV and change in the stroke volume
Normal value of IVC diameter?
1,5-2,5 cm
what can IVC tell us about volume status?
IVC < 1,5cm => volume depletion
IVC > 2,5cm => volume overload
what is the problem with using the gold standars SV do assess fluid response?
What is another option to increase fluids with 300ml withoud actullay giving fluids?
If the patient is already in a good fluid state giving 300ml crystalloid can cause edema
The led raise test because lower extremity containe about 300-400ml fluids
does the acute management of hyperkalemia solve the problem?
No, we need to do hemodialysis to actually remove the K+ from the body
what is the dose of IV K?
what can you do if you want to give a higher dose?
MAX 2g/h!!!! -
PVL- max 2g/500ml IV infusion in a PVK
if you want to give a higher dose use CVK
CVL- max 2g/hr IV KCl (Except in DKA)
what is the exception to giving max 2g/h of K+?
Ketoacidosis
how to find the albumin corrected Ca2+ concentration
measured Ca2+ + 0,02 x (40- Se Albumin)
what should you NOT give as a diuretic in hypercalcemia?
Thiazide
can you give calcitonin alone?
No, always with bisphosphonates
what is the absolute limit of giving Na? and why must it not exceed this level?
0.5 mmol/L/h
can cause pontine myelolysis
management of hyponatremia below 115 mmol/L1
First give 3% NaCl (1-2 mM/hr for total of 4-6mM)
then give 0.9% NaCl (fluid replacement therapy)
have to correct it slowly bcz if fast > risk of osmotic demyelination syndrome (ODS) ( >8-10mM/24hr or >18mM/48hr)
Hyponatremia definition?
Na <135mM
causes of hyponatremia?
water problem: excess relative to Na
impaired water excretion by the kidney
pseudohyponatremia:
hyperLIPIDemia/PROTEINemia
symps of hyponatremia
-cerebral edema
-nausea and vometing
-lethargy, confusion, seizures and coma
hyponatremia therapy?
Hypertonic saline: when Se Na <125mM
Isotonic saline: when Se Na >125mM
how do you know how much saline to give and what is the rate?
Na required = TBW x (desired [Na] - measured [Na])
rate: <0.2mmol/h
max: 0.5mmol/L/h
Hypernatremia definition?
Se Na >145
causes of hypernatremia?
-pure water loss (and inadequate water intake)
-hypotonic fluid loss (sweating)
-salt intake
symptoms of hypernatremia?
-increase thurst
-CNS symps: confusion, weakness, lethargy, coma
hypernatremia therapy?
-water replacement based on formula
-if normovolemia: 5% glucose
-if hypovolemia: isotonic saline first then hypotonic fluids (after correction of volume depletion)
water replacement formula?
H2O deficit = [(measured Na/140)xTBW] - TBW
Hypokalemia definition?
Se K+ <3.5mM
Causes of hypokalemia?
increase excretion:
-diarrhea
-renal loss
-mineralocorticoid excess
-Mg+ deplestion
K+ shift into the cell:
-drugs (insulin, beta-blockers, caffaeine)
-alkalosis
-hyPERthyroidism
symps of hypokalemia?
ECG:
- flat T
- ST depression
- Uwave
- Long QT
- Arrhythmias
- muscle paralysis
- rhabdomyolysis
- metabolic alkalosis
- coma
hypokalemia therapy?
K+ supplimentation (by formula):
- 1 g KCl –> 13.4mM
- 1 g K-citrate –> 9.2mM
Hyperkalemia definition?
Se K >5mM
Hyperkalemia causes?
impaired excretion:
- Renal failure
- Mineralocorticoid deficiency
- pseudohypoaldosteronism
- Drugs (K-sparing, ACEi, NSAIDs)
K+ shift out of the cell:
- Tissue breakdown
- Acidosis
- insulin deficiency
Symps of Hyperkalemia?
ECG:
- peaked Twave
- loss of P waves
- Wide QRS
- heart blocks
- VArrhythmia
- Asystole
- paresthesia
- weakness
- paralysis
- Acidosis
hyperkalemia therapy?
- Ca-gluconate
- insulin
- Na-bicarbonate
- beta2-agonists
- loop diuretix
- Na-polystyrene sulfonate
- dialysis
Hypercalcemia definiton
Ca > 1.29mM
hypercalcemia cause?
MAH: Malignancy associated hypercalcemia
symptoms of hypercalcemia?
stones, bones, cardiac thrones, moans, groans
- renal: nephrocalcinosis, nephrolithiasis
- bone: pain, arthralgia, osteoporosis
- cardiac: bradycardia, SHORT QT (long was hypo-kal)
- abdominal: pain, constipation
- CNS: anexiety, depression
hypercalcemia therapy?
- forced rehydration: 0.9 NaCl 300-500ml/h
- furosemide 20-40 mg IV
- bisphosphonate: osteoclast inhib
- calcitonin
- hemodialysis
- steroid
- RANKL-AB: Denosumab
