CH 20 Newborn: Processes of Adaption

Development of the Lungs: Initiation of Respirations:

- Fetal Lung fluid.

- Surfactant is produced as lungs mature.

- Corticosteroids are recommended for pregnant women.

Surfactant is produced as lungs mature

- Reduces surface tension with alveoli

- Surfactant usually sufficient by 34 to 36 weeks

Corticosteroids are recommended for pregnant women between?

Between 24 0/7 weeks and 33 6/7 weeks of gestation who are at risk of preterm delivery within 7 days, includes for those with ruptured membranes and multiple gestations.

Causes of Respirations in babies?

Diaphragm contracts and is pulled downward and lungs filled with air.

Cardiovascular Adaption: Transition from fetal to neonatal circulation

- At birth, increased blood oxygen and pressure shifts causes shunt closure and pulmonary vessel dilation.

- Closure of Ductus Arteriosus and foramen ovale reverses pressures, establishing adult-like circulation.

- Asphysxia or persistent pulomnary hypertension can reverse pressures causing shunts to reopen patent ductus arteriousus.

Thermoregulation goals

- A neutral thermal environment.

- Maintains body temperature with minimal oxygen need.

- Without an increase in metabolic rate

Non shivering Thermogenesis (NST)

- Primary form of heat production.

- Babies do not shiver, instead they become restless and cry.

- NST is triggered when thermal receptors detect temperatures between 35-36 degrees Celsius.

- The hypothalamic thermal center causes norepinephrine release and activating brown fat.

What are the causes for heat loss in newborns?

- Evaporation

- Conduction

- Convection

- Radiation

What are the clinical manifestations of cold stress?

Thermoregulation

- Neutral Thermal Environment

- Effects of Cold stress

- Hyperthermia

Neutral Thermal Environment

- Infant can maintain stable body temperature with minimal oxygen (O2) need and without increase in MR called the thermoneutral zone.

- Varies according to gestational age, size, and hours after birth.

- Axillary temperature should average 37 degrees with range 36.5 to 37.5 degrees.

- Maintain ideal body temperature via skin to skin when possible.

Effects of cold stress

- Increased MR (metabolic rate) and metabolism of brown fat which result in increase need for oxygen.

- Increases need for glucose which can lead to hypoglycemia.

- Brown fat metabolism releases FAs and metabolic acidosis occurs.

- Can interfere with transport of bilirubin to liver resulting in jaundice.

Hyperthermia

- Increased temperature and leads to increase metabolic rate, and increased need for glucose and oxygen.

- Increased fluid loss.

APGAR Scores

- Appearance

- Pulse

- Grimace

- Activity

- Respiration

Appearance

Color

Pulse

Pulse/HR

Grimace respond to stimulation

reflex response

Activity/muscle tone

Muscle tone and flexion

Respiration

Respiratory effort and cry

Gastrointestinal System: Stomach

- Capacity expands within first few days of life.

- Peristalsis is rapid.

- Gastrocolic reflex is stimulated when the stomach fills.

- Cardiac sphincter is relaxed, leading to regurgitation.

Gastrointestinal System: Intestines

- Long in proportion to infant's size: more surface area for absorption.

- Infants are more prone to rapid water loss with diarrhea.

- Bowel sounds are present within the first hour.

- The digestive tract is sterile until feeding begins.

Gastrointestinal System: Digestive Enzymes

- Cannot digest complex carbohydrates

- Saliva production limited until third month of life

- Ingredients in breast milk more easily digested

Gastrointestinal System: Stools

- Meconium is the first stool excreted.

- Transitional stool is the second type.

- Breastfed infant

- Formula-fed infant

Meconium is the first stool excreted.

- Greenish black with a thick, sticky, tar like consistency

- First stool is usually passed within 12 hours.

- Consists of particles from amniotic fluid.

Transitional stool is the second type.

Greenish brown and looser consistency than meconium.

Breast-fed infant

- Stools are seedy and mustard colored.

- Stools are more frequent than with formula.

- Stools have a sweet-sour smell.

Formula-fed infant

- Stools are pale yellow to light brown.

- Stools are firmer in consistency.

- Stools have the characteristic odor of stools.

Hepatic System

- Maintenance of BG levels (glycogen stored in liver).

- Production of factors for blood coagulation.

- Storage of iron.

- Metabolism of drugs.

- Conjugation of bilirubin.

Hepatic System: Conjugation of Bilirubin

- When newborn liver is not mature enough to clear bilirubin in blood then jaundice occurs

- Source and effect of bilirubin

- Factor in increased bilirubin

Source and effect of bilirubin

- Hemolysis of erythrocytes.

- More red blood cells.

- Bilirubin is a toxic substances.

- Liver must convert to a soluble form (conjugated).

- Unconjugated bilirubin causes jaundice and kernicterus.

Factors in increased bilirubin

- Excess bilirubin production

- Red blood cell life

- Liver immaturity

- Trauma can result in increased hemolysis of red blood cells.

Hepatic System: Hyperbilirubinemia Physiologic jaundice

- Caused by transient hyperbilirubinemia.

- Never present during first 24 hours of life; in the first second or third day after birth.

- Jaundice is visible when bilirubin level is greater than 5 mg/dL.

- Rate of rise and fall of bilirubin level is important.

- Peaks 2-4 days of life and to normal levels at 5-7 days

Hepatic System: Hyperbilirubinemia Pathologic jaundice

- May occur in the first 24 hours.

- Caused by abnormalities causing excessive destruction of erythrocytes.

- Caused by excessive destruction of RBCs or problems of bilirubin conjugation.

- ABO incompatibility, infection, metabolic disorders.

- Treated with phototherapy.

Hepatic System: Jaundice Associated with Breastfeeding Breastfeeding or early onset jaundice

- Occurs in about 13% breastfed infants by about 1 week of age.

- Inadequate intake.

- Sleepy infant with poor suck.

- Delay in elimination of meconium - colostrum is a natural laxative and helps eliminate bilirubin.

- Lack of adequate suckling.

Hepatic System: Jaundice Associated with Breastfeeding True breast milk or late onset jaundice

- Bilirubin levels rise after the first 3 to 5 days.

- Substances in breast milk may interfere with conjugation of bilirubin.

- Closely monitor bilirubin levels.

- Treat with phototherapy and may discontinue breastfeeding or pump for several days while giving formula.

Immune System

- Less effective at fighting off infection

- Immunoglobulin G (IgG)

- Immunoglobulin M (IgM)

- Immunoglobulin A (IgA)

Immunoglobulin G (IgG)

Only immunoglobulin that crosses placenta and provides temporary immunity

Immunoglobulin M (IgM)

First immunoglobulin produced when exposed to infection.

Immunoglobulin A (IgA)

- Receive some from colostrum and breast milk- none from formula.

- Must be produced by the infant

What are some vaccines offered during pregnancy>

- COVID]

- RSV

- Tdap

- Flu