Normal Newborn: Process of adaptation Flashcards
Respiratory Adaptations
- 20-24 weeks alveoli ducts appear
- At 28 to 32 weeks type II cells appear (synthesis and storage of surfactant)
- Surfactant production peaks at about 35 weeks
- Surfactant is comprised of Lecithin and Sphingomyelin L/S ratio=2:1
- At 35 wks the lungs are structurally adequate to maintain lung expansion and gas exchange
Fetal Breathing
- Fetal breathing movement appears about at 11 weeks
- Purpose of breathing is to develop chest wall muscles and the diaphragm
- Lungs are fluid filled
- 80-100ml present at birth
Promotion of Oxygenation
- The respiratory and Cardiovascular systems must undergo the most rapid changes to support extra uterine life.
- Mechanical- Squeezing during vaginal delivery to rid the lungs of fluid
- Chemical- Inspiratory gasp is triggered by the elevation in PCo2, decrease in PO2 and pH.
- Crying helps to open /increase intrathoracic pressure which pushes air into the alveoli which expands the lungs.
- Thermal
- Sensory
Thermogenesis-Heat Production
- Heat is produced by increased metabolic rate, muscular activity and thermogenesis
- Brown adipose tissue or Brown fat produces heat
- Appears at 26-30 weeks and persists for up to 5 weeks after birth
Evaporation
lose heat from being wet; insensible water loss from lungs; throwing up on self
- Keep baby dry
- Change babies frequently
Conduction
lose body heat by contact with something cold
- Dont touch them with cold stuff
- Use a barrier between skin and object; clothes, blankets
- Warm stethoscope
Convection
lose of heat from a cool draft
- Avoid cool drafts/ fans/ AC/ warm clothing
radiation
lose of heat due to being near cold surfaces; widows/walls
Cold stress chain
If baby loses heat they develop cold stress:
Cold stress; develops 3 things
- Hypoglycemia
- Hypoxia
- Hyperbilirubinemia
-
Hypoglycemia: due to increased metabolic rate
- Use up more glucose (brown fat)
— Increased production of fatty acids
—-Causes metabolic acidosis= displaces bilirubin = hyperbilirubinemia/ jaundice
Use up more oxygen
- Decreased surfactant
- Hypoxemia
Elimination
- Meconium- in 8-24hrs of life and for sure by 48 hrs. Thick, black and tarry.
- Transitional stool- for 1-2 days. Thick brown to green
- Breast Milk stools- more liquid and yellow
- Formula stools- brown, solid
- Frequency- once every 2-3 days to 10 times per day
Hematologic System
- Hct may rise 1-2 g/dl above fetal level placental transfusion, low oral intake, decreased extracellular fluid.
- Physiologic Anemia of Infancy- Hgb may decline over the first 2 months.
— Nutritional status
— Neonatal RBCs have a life span of 80-100 days - WBC- Neutrophils elevated for first days of life-due to stress 9.1-34 thousand
Hepatic Adaptations
- Role of the Liver: iron storage, carbohydrate metabolism, conjugation of bilirubin, and coagulation.
- Conjugated Bilirubin- conversion of yellow lipid soluble pigment into water soluble pigment. (direct) Excreted in stool.
- Unconjugated Bilirubin- (indirect) byproduct of Hgb from RBC destruction. Not able to be excreted and is toxic.
What is Bilirubin? Where Does Bilirubin Come From?
An orange, bile pigment waste product, produced from the breakdown of heme- containing proteins (red blood cells).
What Causes Hyperbilirubinemia?
- Increased production
- Short RBC lifespan
- Less Albumin
- Immature liver
- Blood incompatibility
- Intestinal factors
- Delayed feeding
- Trauma - (cephalohematoma)
- Increased fatty acids-brown fat
Types of Jaundice
- Pathologic- Occurs at birth (born jaundice)
- Physiologic- caused by increase in RBC destruction, impairment of conjugation of bilirubin, and increased reabsorption of bilirubin in intestinal tract. Occurs after 24 hours of birth.
- Breastfeeding jaundice- occurs in first days of life
- Breast milk jaundice- occurs from milk composition
