Heat Loss and Thermoregulation of the Newborn

Question 1

Which TWO ways can heat be lost from the body and describe how

Answer 1

Internal gradient - heat is lost from the core to the surface
External gradient - heat is lost from the skin to the environment

Question 2

Why do newborns struggle to maintain their own body temperature? (3 reasons)

Answer 2

• Large surface area compared with body mass
• Thin layer of subcutaneous fat
• Cannot shiver to produce heat

Question 3

If heat loss is not prevented, how many degrees can a newborn’s temperature drop by in 5 minutes?

Answer 3

4.5 degrees

Question 4

How is heat lost through radiation?

Answer 4

Through cold objects in the rooms not in contact with baby, eg. windows

Question 5

How is heat lost is through conduction?

Answer 5

Through contact with cold objects, eg. scales, resuscitiare

Question 6

How is heat lost is through evaporation?

Answer 6

Through wet skin

Question 7

How is heat lost through convection?

Answer 7

Through drafts

Question 8

What is the principal source of heat production in a neonate?

Answer 8

Non-shivering thermogenesis (break down of brown fat)

Question 9

What TWO substances does non-shivering thermogenesis require?

Answer 9

Oxygen
and
Glucose

Question 10

Which areas can brown fat be found in?

Answer 10

Around the neck, axillae (underarms), behind the sternum (chestbone) and between the scapulae (shoulder blades)
Deep layers surrounding adrenal glands, kidneys, trachea and oesphagous

Question 11

Name the SIX stages of cold stree

Answer 11

• Increased metabolism of glucose and oxygen
• Increase in use of glycogen and depletion of glycogen stores
• Hypoglycaemia
• Oxygen consumption increases and increase in respiratory rate
• Requires more oxygen than is available leading to hypoxia and anaerobic respiration
• Respiratory distress

Question 12

What is the normal core body temperature of a newborn?

Answer 12

36.5 - 37.2 degrees celcius

Question 13

What is the core body temperature range of a newborn with mild hypothermia or cold stress?

Answer 13

36-36.4 degrees celcius

Question 14

What is the core body temperature range of a newborn with moderate hypothermia?

Answer 14

32-35.9 degrees celcius

Question 15

What is the core body temperature range of a newborn with severe hypothermia?

Answer 15

Less than 32 degrees celcius

Question 16

What is the core body temperature range of a newborn with severe hyperthermia?

Answer 16

Greater than 37.2 degrees celcius

Question 17

Name SEVEN signs that a newborn may have hypothermia

Answer 17

• Shallow breathing
• Lethargy
• Hypotonia
• Pale, mottled skin
• Hardening of the skin
• Weak sucking
• Hypoglycaemia

Question 18

Name SEVEN signs that a newborn may have hyperthermia

Answer 18

-Tachycardia, tachypnoea
-Apnoea
-Hypotension
Warm extremeties
-Perspiration
-Hypotonia
-Poor feeding

Question 19

List the NINE points of the warm chain

Answer 19

• Warm delivery room (25 - 28 degrees)
• Immediate drying, remove wet towel
• Skin to skin contact
• Breast feeding
• Bathing postponed
• Appropriate clothing and bedding
• Mother and baby together
• Warm transportation
• Warm resuscitation

Question 20

List the THIRTEEN steps to follow after the birth

Answer 20

• Prepare for resuscitation (if expected)
• Dry baby and remove wet towel
• Assess - APGAR score
• Skin to skin contact
• Breast feeding
• Early feeding
• Weight - cover scales
• Delay first bath
• Identification - 2 x name bands
• Examination of the newborn
• Vitamin K prophylaxis
• Document findings
• Mother and baby to transfer together where possible