4. Hyperhydration (isotonic, hypotonic, hypertonic) and edema. Flashcards
1
Q
Causes of isotonic hypervolaemia
A
- Saline + water intake/retention proportional to increase
- Iatrogenic hyperfusion (Caused by medical treatment)
2
Q
Consequences of isotonic hyperhydration
A
- Hydrostatic pressure ↑
- Oncotic pressure ↓
- Intravascular fluid excretion into the interstitium ↑
- EC fluid ↑; IC ↔
- General oedema develops
3
Q
Causes of hypotonic hyperhydration
A
Water intake or retention increases disproportionally to saline increase
4
Q
Consequences of hypotonic hyperhydration
A
- Fluid movement: EC → IC
- EC/IC fluid ↑
- Blood Na+ ↓ (Hyponatraemia)
- Oedema is rare
- IC water transport → Haemolysis/Swelling
5
Q
Causes of hypertonic hyperhydration
A
“Salt poisoning”
- Salt intake ↑ / Salt loss ↓
- Drinking seawater
- Iatrogenic (medical) cause
- Hyperosmotic saline overdose
6
Q
Consequences of hypertonic hyperhydration
A
- Hypernatraemia
- Water transport IC → EC
- Oedema can develop (rarely)
7
Q
Which species are sensitive to hypertonic hyperhydration?
A
- Birds
- Pigs
8
Q
Define oedema
A
Fluid accumulation in the interstitial space
9
Q
The causes of oedema can be split into…
A
- Intravasal factors
- Interstitial factors
10
Q
Intravasal factors causing oedema
A
- ↑ Hydrostatic pressure
- ↓ Oncotic pressure (caused by hypoalbuminaemia)
- ↑ Permeability of blood vessels
11
Q
Causes of hypoalbuminaemia
A
- Liver disease
- Protein loosening enteropathy/nephropathy
- Starvation
12
Q
Interstitial factors causing oedema
A
- ↑ Oncotic & osmotic pressure
- Disorders of the flow of lymph
13
Q
List the types of oedema
A
- Oedema…
- stagnationis
- dyscorticum (cell membrane disorders)
- ex. hypoproteinaemia
- lymphangioticum (capacity change in lymph vessels)
- hormonale (endocrine disturbances)
