Newborn Transition

Question 1

Describe CV Adaptations newborns experience at birth.

Answer 1

1. Pulmonary resistance in vessels drops and allows for greater blood flow and gas exchange
2. Increased pressure & blood flow from left side of the heart
3. Functional closure of the foramen ovale at birth
4. Patent ductus arteriosus functionally closes within 24 hours
   
   • Closes in response to increased O2 and prostaglandin E (PGE2)
   • Permanent closure 3-4 weeks
   • Reopens in response to hypoxia

Question 2

Describe Respiratory Adaptations newborns experience at birth.

Answer 2

• Intrauterine oxygenation occurs by passive diffusion through the placenta
• Blood shunts away from the fetal lungs due to high pulmonary vascular resistance

Question 3

Initiation of respirations at the time of birth occurs in response to what?

Answer 3

• Chemical – activation of chemoreceptors in carotid arteries and aorta
• Mechanical – intrathoracic pressure as fetus passes through birth canal
• Thermal – receptors in skin stimulate the respiratory center in the medulla
• Sensory – handling, stimulating to cry

Question 4

Describe Respiratory Adaptations newborns experience at birth (lungs, mechanical breathing).

Answer 4

• Term fetal lungs contain approximately 20mL fluid/kg of body weight (60-80mL)
  
  • Fluid absorbed through pulmonary circulation and lymphatic system
• Alveoli lined with surfactant
  
  • Lung expansion dependent on chest wall movement and adequate surfactant
  • Surfactant lowers surface tension – reducing the pressure required to keep alveoli open
• Infants are nose breathers
  
  • Can’t breathe through their mouth and feed
• Respiratory rate 30-60/minute
• Visible abdominal breathing – contraction of the diaphragm is the main source of respiratory effort

Question 5

Describe Metabolic Adaptations newborns experience at birth.

Answer 5

• Fetal glucose levels approximately 70% of the maternal level
• At birth, maternal glucose supply abruptly ends:
  
  • Initial drop in newborn glucose occurs 30-90 minutes after birth
  • Glucagon levels increase and insulin levels decrease as liver begins to regulate blood glucose
  • Newborn has limited glycogen/fat stores
  • Initiation of newborn feedings key to stabilization
  • Glucose levels stabilize by 2-3 day of life
• Not routinely assessed unless risk factors for hypoglycemia

Question 6

Describe Hematologic Adaptations newborns experience at birth.

Answer 6

• Fetal hemoglobin more efficient at transporting oxygen
  
  • Greater number of RBC’s
• Rapid breakdown of excess red blood cells
  
  • Release of bilirubin
  • Broken down by liver and bacteria in the duodenum
  • Colostrum is a natural laxative

Question 7

Expand on the bilirubin levels and what it causes in newborns.

Answer 7

• Bilirubin is excreted in urine and stool
  
  • Dependent on PO intake and passage of meconium
• Peaks 72-96 hours after birth
  
  • Gradually decreases to normal level by 14 days of age
• Physiologic jaundice develops when bilirubin levels exceed the liver’s ability to break it down

Question 8

What is the Apgar Scoring criteria?

Answer 8

look at chart

Question 9

What does each range of Apgar scores represent?

Answer 9

• 7–10: A reassuring score that indicates the baby is adapting well to their environment
• 4–6: A moderately abnormal score
• 0–3: A low score that may indicate illness

Question 10

Describe Nursing Care in relation to vital signs.

Answer 10

every 15 minutes until stable for 2 hours

Question 11

What assessment is used to measure gestational age of the newborn?

Answer 11

• The New Ballard Score is one of the most widely used tools to estimate the gestational age of a newborn.
• 6 physical measures; 6 neuromuscular measures
  
  • Higher score = higher gestational age

Question 12

Describe Thermoregulation.

Answer 12

• Balance between heat loss and heat production - neutral thermal environment achieved at approximately 97.5 - 98.6 axillary
• Factors that influence thermoregulation:
  
  • Large body surface to body weight ratio
  • Lose heat 4x’s faster than adults
  • Thin layer of subcutaneous fat
  • Blood vessels close to surface of skin
  • Limited stores of glucose and fat

Question 13

Nursing care for thermoregulation?

Answer 13

• Drying the newborn immediately after birth is essential to prevent heat loss from evaporation.
• Skin-to-skin contact (kangaroo care) is an effective way to maintain the newborn’s body temperature.
• Radiant warmers and incubators are commonly used to help maintain body temperature
• Swaddle the newborn or use caps and socks

Question 14

What are the different types of heat loss in newborns?

Answer 14

• Convection
• Radiation
• Evaporation
• Conduction

Question 15

Describe Convection heat loss and list some interventions.

Answer 15

• Heat loss to cooler air currents or drafts, which carries heat away from the baby’s body.
• Warm environment and room temperature, incubators or radiant warmers

Question 16

Describe Radiation heat loss and list some interventions.

Answer 16

• Heat loss to cooler surfaces, without direct contact.
• Keep away from cold surfaces (windows), use incubators or radiant warmers

Question 17

Describe Evaporation heat loss and list some interventions.

Answer 17

• Heat loss that occurs when moisture on the newborn’s skin evaporates, taking away body heat.
• Dry baby, put on hat

Question 18

Describe Conduction heat loss and list some interventions.

Answer 18

• Heat loss that occurs when the newborn’s body comes into contact with cooler surfaces.
• Pre-warm surfaces, warm blankets, skin-to-skin

Question 19

Hypothermia s/s in newborns?

Answer 19

• Vasoconstriction (mottled, acrocyanosis)
• Tachypnea
• Tachycardia
• Hypoglycemia
• Poor muscle tone
• Poor feeding ability
• Lethargy

Question 20

Describe hyperthermia in newborns.

Answer 20

• Often due to inappropriate use of external heat sources
• Sweat glands not functional in newborns