Hydration status and signs of dehydration

Question 1

What are the cases of dehydration?

Answer 1

Decreases input: increased risk with age, decreased oral intake

Increased output: diabetes, diarrhoea and vomiting, fever, drugs

Insufficient replacement fluid

Major haemorrhage

Sepsis

Question 2

What are the causes of fluid overload?

Answer 2

Iatrogenic – excess fluid prescribed

Cardiac failure

Renal failure

↑ADH secretion

Question 3

How do you review hydration status? (without assessing patient)

Answer 3

• Fluid balance (Large positive /negative balance)

Observation chart (tachycardia, BP, Temperature, O2 saturations)

Medications (diuretics, heart medication, nephrotoxic drug)

Bloods (↑↑Urea, ↑Creatinine, ↑albumin, ↑Haematocrit)

Chest X-ray (pulmonary oedema, heart failure)

Question 4

How do you manage dehydration?

Answer 4

Fluid challenge (250-500ml Hartmann’s or 0.9% NaCl)

Assess why they are dehydrated

Increase oral intake (if possible

Maintenance fluids

Consider altering medications

Question 5

How do you manage overload?

Answer 5

Nitrates

Diuretics

CPAP (if severe enough)

Assess why they are overloaded?

Question 6

How should you assess a patients hydration status) (HINT: exam)

Answer 6

1. Introduction 
• Introduce self and Identify patient
• Gain Consent and acquire a chaperone
• Wash hands
• Ask about pain
• Position patient and ensure adequate exposure

2. General inspection
• Body habitus (obese/cachexic)
• Oedema
• Breathless (suggesting fluid overload)
• IV lines, Nasogastric tubes
• ‘Nil by mouth’ signs/ Food/drink around bed
• Catheter (how much? What colour?)
• Vomit bowels
• Surgical Drains
• Stomas

3. Examine the hands
   • Assess warmth
   • Capillary refill time
   • Assess skin turgor
4. Examine the Arms
   • Pulse (weak, ↑in dehydration and overload)
   • Lying/standing BP (a difference of >20mmHg is significant)
5. Examine the neck
   • Carotid pulse (character- weak/thready?)
   • JVP (>4cm ↑ is significant – Overload?)
6. Examine the head
   • Temperature (fever – dehydration?)
   • Sunken eyes (dehydration)
   • Dry mouth (dehydration)
7. Examine the chest
   • Parasternal heaves (right heart dilatation)
   • Displace apex beat (left heart dilatation)
   • 3rd heart sound (Heart failure, fluid overload)
8. Examine the back and legs
   • Lung bases (crackles = LVF)
   • Sacral oedema (RVF)
   •Ankle oedema (RVF)

9. Conclude
• Thank patient 
• Review charts and blood
• Daily weights
• Repeat blood (U&Es, LFTs, FBCs)
• CXR (pulmonary oedema)
• Specific gravity of urine