Chapter 25- Physiological Newborn Adaptations Flashcards
14 Questions on exam (and chapter 26)
How long is the neonate period?
Birth to 28 days
What are the 3 stages of the newborn transition period?
1) INITIAL Period of REACTIVITY
2) Period of Relative INACTIVITY
3) SECOND Period of REACTIVITY
What are the physiological changes that occur to the newborn for a successful transition?
– Spontaneous breathing
– Thermoregulation
– Successful Cardiopulmonary changes
– Independent system functioning including
Ingesting,
Retaining,
Digesting,
Eliminating waste,
Regulating weight
How long does the transition period last in a newborn?
The transition lasts about 6-8 hours
What Physiological Changes occur in the newborn in the Initial Period of Reactivity?
- HR of 160-180 bpm
- Irregular RR 60-80 breaths/min with crackles, grunting, nasal flaring, and retractions
- Alert, spontaneous startles, tremors, crying, head side to side
- Audible bowel sounds and possible meconium
How long does the Initial Period of Reactivity last?
Occurs within 30 minutes of birth
What Physiological Changes occur in the newborn in the Period of Relative Inactivity?
- Sleep and Decreased motor activity
- Pink colour
- RR rapid and shallow, 60 breaths/min; NOT laboured
- Audible bowel sounds; may note peristaltic waves over abdomen
How long does the Period of Relative Inactivity last?
Occurs 60-100 mins post birth
What physiological changes occur in the newborn in the Second Period of Reactivity?
- Brief periods of Tachycardia and Tachypnea due to increased muscle tone
- Skin colour changes
- Mucous production (higher in C-section babies)
- Passing Meconium
How long does the Second Period of Reactivity last?
Occurs 2-8 hours after birth, lasting 10 mins-several hours
What is the Average Time window for newborns to pass Meconium?
Within 24 hours of birth. Most pass Meconium by 48 hours of life.
Signs of Respiratory Distress in newborn
- Intracoastal and subcostal Retractions
- Central Cyanosis
- Pallor (acrocyanosis is normal)
- <30 or >60 breaths/min
- Apnea
- Nasal flaring, grunting
Notable in the first 2 hours after birth, should not last longer
What is Transient Tachypnea of the newborn?
It is caused by a delay in the clearance of fetal lung fluid after birth, which leads to ineffective gas exchange, respiratory distress, and tachypnea.
What is the significance of Transient Tachypnea in C-section babies?
When labour does not occur before birth (c section babies) the catecholamine surge that promotes lung fluid clearance is not effective and therefore they have more fluid retention. They are also not squeezed through the vaginal canal which would cause them to retain more mucous.
What changes occur to the Ductus Arteriosus after birth?
Prostaglandin aids in its closure. Functionally closed after birth, permanent closure 3-4 weeks after and then it becomes a ligament. Can open in response to low oxygen levels. Can be detected as a heart murmur upon auscultation.
What changes occur to the Foramen Ovale after birth?
Functionally closed after birth caused by pulmonary blood flow from the left side of the heart increasing pressure in the left atrium. Crying may temporarily reverse flow through the foramen and can cause mild cyanosis.
At what point is a newborn checked for Congenital Heart Disease?
At 24 hours of age.
What is the average Heart Rate of a newborn after birth?
- HR is 110-160 bpm, increasing with crying and decreased during sleep
What is the average Blood Pressure of a newborn after birth?
- BP is (60-80 sbp/40-50 dbp)
What are Cardiac Signs of Distress in a newborn?
- Persistent tachy/bradycardia
- Unequal or absent pulse
- Bounding pulse
- Hypertension or hypotension
- Prolonged Cyanosis or Pallor
What are positive effects of Delayed cord clamping (DCC)?
Expands blood volume, increasing BP and lowering the chance of intraventricular hemorrhage and necrotizing enterocolitis
Are Red Blood Cell levels higher or lower in a newborn? Why?
Born with increased levels of RBCs at birth to compensate for poor fetal circulation.
What is Polycythemia?
Increase in hematocrit levels in preterm newborns. Causes the blood to be thicker.
Can occur because of DCC, maternal hypertension, diabetes, intrauterine growth restriction
What is Neutrophilia?
High neutrophil count which can be a sign of a underlying condition such as infection or inflammation. Leukocytes are slow to recognize and fight infection in early life.
What is a Direct Antibody Test (DAT)?
Used to detect antibodies present in newborns blood. DAT tests for evidence of a reaction between the mother’s and baby’s blood groups. Samples obtained through cord blood. Can detect conditions such as anemia and jaundice.
What newborn Temperature reading indicates need for Increase Warming Interventions?
<36.5 degrees Celsius
Warm slowly to avoid shock
What is the Nurses Priority Care for the Thermogenic system?
Maintain a neutral thermal environment (heat balance) to minimize glucose and O2 consumption.
What are the benefits of Skin-Skin contact after birth?
Lowers conduction and radiant heat loss. Increases newborn temperature control. Encourages parent and newborn interaction.
What Physical Characteristics put newborns at higher Risk for Heat Loss?
- Thin layers of subcutaneous fat
- Blood vessels are close to surface of the skin
- Environment temperature impacts blood temperature
- Larger body surface to body weight ratio
What are the 4 ways newborns can Lose Heat?
Conduction, Radiation, Convection, Evaporation
What is Non Shivering Thermogenesis?
The newborn metabolizes brown fat (adipose tissue) to produce more heat. Brown fat in newborns is located in their back, neck and shoulders.
How does heat loss occur through Convection? What is an appropriate intervention?
The surrounding air pulls heat from the body.
- Keep the ambient temperature at 22-26 C
- Wrap the baby in a blanket or put on a cap
How does heat loss occur through Conduction? What is an appropriate intervention?
Through direct contact with a cooler surface which draws heat away from the baby (exam table)
- Place a blanket or covering on the surface
How does heat loss occur through Radiation? What is an appropriate intervention?
Indirect heat loss to a cooler surface from the baby (windows, lamps)
- Place crib away from windows
How does heat loss occur through Evaporation? What is an appropriate intervention?
Heat loss when liquid evaporates to vapour
- Dry the baby properly after baths/birth
What is the physiological response to Hypothermia and Cold stress in a newborn?
Vasoconstriction to preserve heat causing
- Cool, pale, mottled appearance
- Increased RR due to increased oxygen demand
- O2 is redirected away from brain and heart to maintain thermogenesis
- Can lead to Transient Respiratory Distress related to poor pulmonary perfusion and hypoxia
- Metabolic acidosis caused related to low pH
-Hyperbilirubinemia and hypoglycemia
Signs of Renal Concerns and Dehydrationin a newborn
- Low urine output
- Poor skin turgor
- Indent in fontanelles/visible
- Low weight
- Cystic kidneys (masses)
Signs of Gastrointestinal problems in a newborn
- No meconium in 24 hours
- Abdominal distension
- Hernias
- Diarrhea
- Projectile vomiting
Signs of Hypoglycemia in a newborn
- Jittery, shaking (rule out other causes)
- Lethargy
- Apnea
- Feeding problems (poor suction)
- seizures ( <1.5 mmol/L)
What are normal levels of Blood Glucose in newborns? What is a dangerous Level and an Intervention?
First hours after birth: 2.5-3 mmol/L
Day 3: ranges 4-6 mmol/L.
Levels below: 2.7 mmol/L are hypoglycemic
Less than: 2.2 mmol/L is cause for concern and intervention.
Colostrum during breastfeeding contains high levels of glucose which can help to correct hypoglycemia
Why is the difference between Conjugated and Unconjugated bilirubin?
Unconjugated bilirubin is insoluble and binds to circulating plasma protein (albumin); it must be conjugated to be able to be excreted by the body
Conjugated bilirubin is soluble and can permeate other tissues; cause for concern if it passes the blood-brain barrier as it causes neurotoxicity (encephalopathy/kernicterus)
In proper functioning conjugated bilirubin is excreted through urine and feces
How does Jaundice occur?
Bilirubin is produced by the breakdown of hemoglobin in RBCs, specifically the Heme portion that is further broken down into iron and unconjugated bilirubin.
The unconjugated bilirubin is too much for the liver to coagulate fast enough resulting in high plasma levels of bilirubin
What aspects of newborn Physiology put them at Risk for Hyperbilirubinemia (jaundice)
- High RBC count at birth and shorter RBC lifespan therefore a greater need for bilirubin synthesis
- The ability of the liver to conjugate bilirubin is reduced during the first days after birth (can only excrete 2/3 of bilirubin)
- Fewer bilirubin binding sites due to lower albumin levels (less binding to albumin therefore must conjugate and be excreted)
- Conjugated bilirubin can become unconjugated and recirculated in the intestines, increasing bilirubin levels
What is the greatest risk factor for hyperbilirubinemia? Name other contributing factors
Preterm babies (Affects liver and brain metabolism and albumin binding sites)
- Brushing
- Delayed meconium
- Delayed feeding
- GI obstructions
- Medications that inhibit the binding of bilirubin
What is Physiological Jaundice?
- Represents the newborns physiological immaturity to handle increased bilirubin production
- Visible jaundice appears between 24 to 72 hours of age
- Total serum bilirubin (TSB) usually peaks by day 3 and then falls
- Usually does not require treatment
- Occurs in 60% of at term newborns and 80% of preterm infants
What is Pathological Jaundice?
- Occurs within the first day of life and is detected through blood tests
- Persist even with treatment
What are some common causes of Pathological Jaundice?
- Intrinsic blood disorders: maternal and fetal blood type (or Rh factor) differ creating antibodies that break down RBCs causing jaundice; excessive vitamin K, viral infections; DAT testing
- Extravascular hemolysis: hemorrhage (excessive destruction of RBCs)
- Impaired hepatic function: hypothyroidism
- Biliary obstruction: corrected by surgery; if not corrected can lead to cirrhosis of the liver
What causes Breastmilk Jaundice?
Breastmilk containing high levels of fatty acids (harder for the liver to digest) which inhibits bilirubin conjugation
What is Kernicterus?
Kern (“nucleus”) + Ikterus ( jaundice”)
- Caused by deposition of unconjugated bilirubin into the basal nuclei of the brain
- Symptoms are hypotonia, absent reflexes, coma, followed by excitation
About half of the infants survive but are affected with CP, hearing impairment and neurological deficits
Jaundice treatment measures
Frequent Feeding:
- Every 2 hours
- Encourage breastfeeding
- Use of supplemental systems if required
- Early feeding act as laxative and promote GI elimination & bacterial colonization
- Intensive Phototherapy: causes loose stools, dehydration, cold stress or hyperthermia, increased metabolic rate, dark urine, nausea/migraines for caregivers due to lights
- Exchange Transfusion: 85% RBC lowers bilirubin by 50%
- IVIG (immunoglobulin)
What Physiological changes occur in the newborn’s Immune system?
- Higher risk for infection
- Passive immunity (igG) from mother for the first 3 months
- If fever is present before 3 months of age it is a medical emergency
- Breastmilk provides newborn with some immunity
- The newborn is capable of producing a protective immune response to vaccines
Signs of Infection in a newborn
Temperature: fever or hypothermia, Cognitive: lethargy, irritability
GI: poor feeding, vomiting or diarrhea, Motor: decreased reflexes
Integumentary: pale or mottled skin
Respiratory: Apnea, tachypnea, grunting, retractions
What is the Vernix Caseosa?
Thick white coating that is fused with the epidermis and comes off on its own. It serves as a protective coating.
What is lanugo?
Lanugo: fine hair
What is Milia?
Clogged sweat glands. Pimple-like appearance but must be left alone and not irritated
What is Congenital Dermal Melanocytosis (Mongolian Spots)
Bluish black area pigmentation; fade gradually
What is the difference between Caput Succedaneum and Cephalohematoma?
Caput Succedaneum: generalized EDEMAtous area of the scalp; EXTENDS across the suture line
Cephalohematoma: collection of blood between a skull bone and its PERIOSTEUM; does NOT cross a cranial suture line
What are signs of Developmental Dysplasia of the Hip?
- Asymmetry of gluteal and thigh
folds with shortening of the thigh (Galeazzi sign) - Limited hip abduction, seen in flexion
(Ortolani test) - Apparent shortening of the femur, as indicated by the level of the knees in
flexion (Allis sign). - Ortolani test with femoral head moving in and out of acetabulum (in 1-2 months old).
What is the difference between Tremors/jitteriness and Seizure activity?
Tremors: easily elicited by motions or voice and cease with gentle restrain of the body part
Seizure activity: continues even with restrain, ocular changes, autonomic changes
What are the Sleep-wake states?
Deep sleep
Light sleep
Drowsy
Quiet alert
Active alert
Crying.
What are the infants Responses to Environmental Stimuli?
Habituation, Consolability, Cuddliness, Irritability, and crying
What is Nevi/Nevus?
A small growth on the skin that is usually pink, tan, or brown and has a distinct edge
What is Erythema toxicum?
A transient rash
What is Ecchymosis?
Brushing
What is Desquamation?
Peeling
