CCP 340 Neonatal Anatomy and Physiology πΆπ» Flashcards
Neonatal airway anatomical features
aka from an ANATOMICAL perspective why do neonates suck to intubate
- VERY Small, compressible airway
2. Relatively large tongue and occipital area
Neonatal airway physiologic features
aka from an PHYSIOLOGIC perspective why do neonates suck to intubate
- Low Functional Residual Capacity
2. High metabolic rate and oxygen consumption (desaturate FAST)
Emergency evaluation of the newborn should be framed by three questions
- Was it a term birth? (37 weeks)
- Does the neonate have good tone?
- Is the neonate breathing or crying effectively?
Negative responses to any of the above questions should prompt further evaluation and likely initiation of resuscitation procedures.
Positive responses to all questions and no additional provider concerns indicate that resuscitation is likely not needed and the infant can stay with the mother.
main aetiologies for Neonatal distress and arrest
common: respiratory
rare: severe anemia or congenital/cardiac
location for PRE-ductal pulse oximetry
right upper extremity
what percent of term infants require drying and stimulation to trigger breathing reflex
10%
what percent of term infants will breathe spontaneously within the first 30 s of life and require no additional management
85%
what percent of term infants require positive pressure ventilation to trigger breathing reflex
3%
what percent of term infants require intubation for respiratory support
2%
what percent of full-term infants require chest compressions and epinephrine to achieve transition
0.1%
detail of the pathophysiology related to rapid shift in fetal circulation upon delivery
aka, how does CVS/respiratory shit change for baby once it gets outta mom
- Clamping of the umbilical cord β the babyβs SVR
- Blood flow through the ductus venosus β and gradually closes over the first 3-7 d, thereby β blood flow to the IVC
- Lung expansion causes a β in pulmonary vascular pressure, which β right atrial flow
- The β in right atrial flow ceases the flow through the foramen ovale, which then closes almost immediately.
- These alterations in blood flow through the ductus arteriosus β its closure within the first week of life
- obtaining an SpO2 on the right hand (preductal) gives the most accurate assessment of central oxygen levels.
- This process also explains the gradual shift in appropriate O2 levels from <65% at birth to 85%-95% at 10 min of age
maternal risk factors which increase prenatal stress on the fetus leading to higher rates of neonatal resuscitations
AKA, in what cases should you anticipate an NRP resus
Active infection Gestational diabetes Gestational hypertension Illicit drug use Lack of prenatal care Pre-eclampsia/eclampsia Prescription or hospital-administered drug use (including general anesthesia or magnesium therapy)
The normal neonatal respiratory rate
40-60 breaths per minute
The normal neonatal heart rate
120-160 beats per minute
how does PPV help a neonate βtransitionβ
- The initiation of respiration is the first task in neonates.
- positive-pressure respiratory support aids in fluid absorption in the lungs and expands the lung volume β a decrease in PVR β an increase in right atrial flow β improved CVS/pulmonary dynamics/oxygenation
Pregnancy complications and fetal factors which play a role in an increased likelihood of NRP resuscitation requirements
Multiple gestation (particularly <35 wk) Oligo- or polyhydramnios Hydrops fetalis Fetal congenital malformations Premature rupture of membranes (rupture before labor begins) or prolonged rupture (>18 h) Preterm delivery (<36 wk) Non-reassuring fetal heart rate or bradycardia Meconium-stained amniotic fluid Breech presentation Shoulder dystocia Nuchal cord Emergency cesarean section
define gestational age
Gestational age is loosely defined as the number of weeks between the first day of the motherβs last normal menstrual period (LMP) and the day of delivery
APGAR: βAppearanceβ
Blue, pale (0)
Centrally pink (1)
Pink (2)
APGAR: βPulseβ
Absent (0)
<100 bpm (1)
>100 bpm (2)
APGAR: βGrimaceβ
Floppy (0)
Minimal responsiveness (1 )
Responds to stimulation (2)
APGAR: βActivity (tone)β
Absent (0)
Flexed (1 )
Active (2)
APGAR: βRespirationsβ
Absent (0 )
Slow (1)
Vigorous (2)
neonatal hypoglycaemia definitions
- Hypoglycemia in the first 1-4 h of life is considered at levels <2.2 mmol/L
- From 4-24 h of life, glucose should be >2.5 mmol/L
when does a fetus become viable?
23 weeks +/- 1wk