Dehydration

Question 1

What are some signs of dehydration? Outline good and less reliable signs.

Answer 1

• Better signs: weight loss (GS if measured), delayed CRT (>2s), inc RR
• Good signs: tissue turgor, tachycardia, hypotension, irritable/reduced consciousness, deep acidotic breathing, sunken fontanelles, peripheral shutdown
• Less reliable signs: sunken eyes, lethargy, dry mucous membranes
  (JVP hard to elicit in small children)

Question 2

How can you assess the degree of dehydration?

Answer 2

Mild (<4%):
- No signs (only may more thirsty)

• Moderate (4-6%):
  • Delayed CRT> 2 secs
  • Increased respiratory rate
  • Mild decreased tissue turgor

Severe (>/=7%):
• Very delayed CRT > 3 secs, mottled skin
• Other signs of shock (tachycardia, irritable or reduced conscious level, hypotension is very late)
• Deep, acidotic breathing
• Decreased tissue turgor

Question 3

In managing dehydration, what are the main types of fluid loss/requirements to consider?

Answer 3

1. Hypovolaemic shock
2. Deficit
3. Maintenance fluid requirements
4. Ongoing losses

Question 4

How do you manage hypovolaemic shock in paediatrics?

Answer 4

1. 20mls/kg normal saline (remember, sometimes 10mls/kg needed if rehydration must be slow e.g. DKA)
2. Extra 20mls/kg normal saline (40mls/kg total) if still signs of hypovolaemia

If still signs of hypovolaemia after 40mls/kg:
○ Blood transfusion needed (fully cross-matched blood preferred), may need FFP + plts
○ Consider inotropic support if not improving
○ Get help
□ Seniors, MET, PIPER

Do not include this fluid volume in any subsequent calculations of hydration.

Question 5

How do you calculate a child’s fluid deficit?

Answer 5

A. What clinical signs of dehydration?
B. What %body weight of dehydation does that correspond to?
C. % x body weight = fluid lost (mls)
D. Replaced over time period (depending on situation)

Question 6

How do you calculate a child’s maintenance fluids?

Answer 6

A. Calculate via 4:2:1 rule
B. Most children should receive 2/3 of this, due to ADH secretion in stress - unless dehydration
- Esp acute CNS conditions like meningitis - should be further restricted
- 100mls/hour (2400mls/day) is the normal maximum amount

Question 7

How do you calculate a child’s ongoing fluid losses?

Answer 7

• Figure out by measuring losses e.g. vomiting, catheter, nappy weights
• Replace based on per hour/4hr etc, depending on situation
• Normal (0.9%) saline may be sufficient

Question 8

What monitoring should be done when administering fluids?

Answer 8

• Vitals
• Weight
• Bloods if needed - glucose, UEC

Question 9

What are some possible complications of fluid resusc?

Answer 9

• Hypothermia
• Coagulopathy
  ○ Exacerbated by hypothermia
  ○ Give 2 units of fresh frozen plasma for every 4 units of packed red blood cells given
• Hypoglycaemia
• Hypotension