Chapter 9 and 10 Flashcards
what does amniotic fluid do to the fetal lungs
inhalation helps growth of fetal lung tissue, absorption accelerates during labor, birth and a few hours after which means decreased pulmonary resistance to blood flow initating air breathing
What do chemical factors do to initiate first breath
hypercarbia, acidosis, hypoxia - these factors stimulate respiratory system of brain to initiate breathing
what do sensory factors do to initiate the first breath
overwhelming new stimuli like tactile visual olfactory and auditory
what do thermal factors do to initiate first breath
drastic change in temp stimulates respiratory response to prevent cold stress and respiratory depression need to dry in place infant skin to skin
what do mechanical factors due to initiate first breath
fetal chest compression thoracic squeeze during vaginal delivery pushes fluid out of lungs, chest recoil after newborn trunk delivered creates intrathoracic pressure the air replaced the fluid that was squeezed out remaining lung fluid pushed into lymphatic and circulatory system and absorbed within a few hours this doesn’t happen in C-section so respiratory distress
what are some complications from O2 therapy
Broncopulmonary dyspnea and retinopathy of prematurity
what is a L/S ratio and how do you get it
lectin-to-sphingomyelin - Mature longs =2:1, less then 35 wks= less lactin, An amniocentesis can be done to get ratio
what happens to the fetal lungs after birth
lung expansion after birth stimulates surfactant release which decrease in surface tension within alveoli thus preventing alveolar collapse
what are some factors that interfere with fetal breathing
prematurity, birth asphyxiation can adversely affect lung compliance and surfactant production, respiratory distress, translate tachypnea of newborn
ss of respiratory distress syndrome
grunting, accessory muscle, retractions, nasal flaring, tachypnea
what is the treatment for respiratory distress syndrome
air maintenance and oxygenation by humidified O2 continuous positive airway pressure (CPAP) it is less invasive than intubation, but want to wean ASAP so they don’t become dependent
what is transient tachypnea of newborn
aka respiratory distress syndrome type 2 - delayed clearance of fetal lung fluid (usually resolves 2-3 days)
what are the risk factors for transient tachypnea of newborn
c-section, large baby, late preterm (34-36wks)
how is transient tachypnea of newborn
via blood gasses showing respiratory acidosis
what are the ss of transient tachypnea of newborn
tachypnea, grunting, retractions, cyanosis, nasal flaring
what is the treatment for transient tachypnea of newborn
hold oral feeds over 6oz to decrease risk of aspiration, CPAP at 40% for 24-48 hours
what does hypoxia trigger
impulses from chemoreceptors to stimulate respiratory center in medulla
what does sudden temp change trigger
sensors in the skin to send impulses that stimulate breathing
when does the foramen ovale and how
closes when the pressure in the LA is higher then RA pressure, semi closes 1-2 hours after birth and permanent closure by 6mths
when and how does the ductus arteriosus close
constricts preventing deoxygenation blood from pulmonary artery from entering aorta, usually closes within 72 hours with incomplete closure you can hear murmur in 2nd intercostal space/left sternal border, permeant closure at 3-4 wks and then called ligamentum arteriosum
when and how does the ductus venosus close
clamping umbilical cord occludes blood flow into umbilical circulation so closes ductus venosus which forces blood flow to liver, name is now ligamentation venosum by first week
what position do premies need to maintian body temp
flexed position
what increases heat production in babies
peripheral vasoconstriction , nonshivering thermogenesis
how do you prevent hyperthermia in newborns
sweatglands no developed until 1 mth so the baby does peripheral vasodilation and evaporation of insensible H2O loss