Dehydration: More Than Just Feeling Thirsty 💧

Water is essential for life, but fluid balance can be easily disrupted by illness, exertion, or inadequate intake. Dehydration ranges from mild to severe, with progressive signs that can escalate from thirst to hypovolaemic shock.

🚨 What Happens When the Body Loses Water?

🔹 Mild Dehydration (1–3% fluid loss)

• ✔ Increased thirst (early warning system)
• ✔ Dry mouth and slightly darker urine due to reduced renal filtration
• ✔ Subtle cognitive changes (mild fatigue, difficulty concentrating)
• ✔ Slight tachycardia as compensation

🔹 Moderate Dehydration (4–6% fluid loss)

• ⚠ Dizziness, postural hypotension due to reduced circulating volume
• ⚠ Reduced skin turgor (tenting effect when pinched)
• ⚠ Oliguria (markedly reduced urine output) as kidneys conserve fluid
• ⚠ Irritability, confusion due to decreased cerebral perfusion

🔹 Severe Dehydration (>7% fluid loss)

• 🛑 Hypotension, tachycardia, weak pulses → Signs of hypovolaemic shock
• 🛑 Cold, mottled extremities → Peripheral vasoconstriction to maintain central perfusion
• 🛑 Sunken eyes, severe lethargy → Profound fluid depletion
• 🛑 Anuria → Kidneys unable to sustain filtration

🩺 How Do We Assess Hydration Status?

🔍 Adults & General Populations

• ✅ Skin turgor test (tenting effect)
• ✅ Capillary refill time (<2 sec normal, prolonged in dehydration)
• ✅ Orthostatic BP changes (drop of >20 mmHg systolic or >10 mmHg diastolic)

🔍 Paediatrics & Elderly

• ✅ Sunken fontanelles in infants
• ✅ Tear production (absence indicates dehydration)
• ✅ Dry mucous membranes
• ✅ Behavioural changes (lethargy, irritability)

🔍 Athletes & Heat-Exposed Populations

• ✅ Urine colour chart (darker shades signal dehydration)
• ✅ Weight loss tracking (acute water depletion post-exercise)
• ✅ Core temperature monitoring (in heat-related dehydration)

💡 Key Takeaway

Dehydration isn’t just about thirst—it’s a progressive physiological state that can lead to circulatory collapse if untreated. Early recognition and appropriate interventions (oral vs. IV rehydration) are crucial in both clinical and everyday scenarios.

💭 Which dehydration assessment methods have you read about? Let’s discuss below! 👇