Physiologie
Physiopathologie
H.M
, HYDRATION DISORDERS
SUMMARY
🧪 Learning Objectives
• Understand the pathophysiological mechanisms of
hydration disorders
• Know how to make a positive diagnosis
• Identify signs of severity
• Plan appropriate management
• Master monitoring and prevention
💧 I. Water Metabolism
1. Body Fluid Compartments:
• Water = 60% of body weight (higher in infants,
lower in elderly/obese)
• Two main compartments:
• Intracellular (40%)
• Extracellular (20%): interstitial fluid, plasma,
lymph
2. Osmolarity & Tonicity:
• Osmosis = water movement along concentration
gradient
• Osmolality = number of dissolved particles per kg
of water
• Tonicity = depends on active osmoles (e.g., sodium,
glucose)
3. Water Balance:
• Inputs: thirst, food and fluids
• Outputs: kidneys (regulated by ADH), skin, GI
tract
• Regulation: via ADH, thirst center, and
osmoreceptors
Physiopathologie
H.M
, HYDRATION DISORDERS
SUMMARY
🧪 Learning Objectives
• Understand the pathophysiological mechanisms of
hydration disorders
• Know how to make a positive diagnosis
• Identify signs of severity
• Plan appropriate management
• Master monitoring and prevention
💧 I. Water Metabolism
1. Body Fluid Compartments:
• Water = 60% of body weight (higher in infants,
lower in elderly/obese)
• Two main compartments:
• Intracellular (40%)
• Extracellular (20%): interstitial fluid, plasma,
lymph
2. Osmolarity & Tonicity:
• Osmosis = water movement along concentration
gradient
• Osmolality = number of dissolved particles per kg
of water
• Tonicity = depends on active osmoles (e.g., sodium,
glucose)
3. Water Balance:
• Inputs: thirst, food and fluids
• Outputs: kidneys (regulated by ADH), skin, GI
tract
• Regulation: via ADH, thirst center, and
osmoreceptors
