Osmoregulation Flashcards
1
Q
Plasma Osmolality Calculation
A
Posm = (2XNa) + (gluvose/18) + (BUN/2.8)
2
Q
NaCl affect on Plasma Na,
ECF/ICF, urine Na
A
INC Plasma Na
INC ECF
INC Urine Na
DEC ICF
3
Q
water affect on Plasma Na,
ECF/ICF, urine Na
A
DEC Plasma Na
INC ECF
INC Urine Na
INC ICF
4
Q
Isotonic Saline affect on Plasma Na,
ECF/ICF, urine Na
A
No affect Plasma Na
INC ECF
INC Urine Na
No affect ICF
5
Q
Mechanisms of ANP
A
- Natriuresis -> Diuresis
- Close Na+ channels + suppress RAAS
6
Q
Hyponatremia S/S
A
- AMS
- Fatigue
- headache
- Loss of appetite
0 muscle spasm/cramp
7
Q
SIADH Diagnosis
A
- Hyponatremia + Hyposmolality
- Euvolemia
- Urine Osm > 200
- Normal renal/cardiac/hepatic/pit/thyroid/adrenals
- absence of antidiuretics
- Urine Na > 20 mew/L
8
Q
Hyponatremia Therapy
A
- Water restriction (SIADH; CHF; Cirrhosis)
- Isotonic saline or PO NaCl
- Hormones replacement (Hypothy or Cort def)
9
Q
3% saline algorithm
A
Na+ req = total body water X (desired [Na] - Current [Na])
Infusion rate <0.5 meq/L/hr OR 10 meq/L/24
10
Q
Hyperacute Hyponatremia
A
- Inadequately trained long distance runners
- A/S Pulmonary edema
- Tx Loop blockers + Hypertonic saline bolus
