Transition to Extrauterine Life Flashcards
What does the fetus depend on for gas exchange?
The placenta
The placenta facilitates gas exchange between maternal and fetal blood.
What percentage of fetal cardiac output flows through the placenta?
40%
This highlights the importance of placental circulation in fetal development.
What is the ductus venosus?
A fetal shunt that directs blood from the umbilical vein to the inferior vena cava
40-60% of umbilical venous blood bypasses the liver, which allows a significant portion of well-oxygenated blood to enter the heart directly
It plays a crucial role in fetal circulation.
What are the main characteristics of fetal lungs?
Decreased blood flow, thick muscular layer, high pulmonary vascular resistance
These characteristics differ significantly from postnatal lung physiology.
When does surfactant begin to be present in the fetus?
By 20 weeks gestation
Surfactant is critical for lung function after birth.
What is hypoxemia?
Low oxygen in the blood
It can lead to various complications in the fetus.
What is the difference between hypoxemia and hypoxia?
Hypoxemia refers to low oxygen in the blood, while hypoxia refers to low oxygen levels in the tissue
Both conditions are critical to monitor in fetal health.
What is acidosis?
Increased concentration of H+ in the tissue
It can arise from respiratory or metabolic causes.
What causes respiratory acidosis in a fetus?
Increased CO2 from lack of exchange
Can occur rapidly and may lead to significant metabolic acidosis if prolonged.
What is asphyxia during labor primarily due to?
Ongoing progressive hypoxia
This leads to cellular metabolic changes and can cause significant harm.
True or False: Neonatal depression is synonymous with perinatal asphyxia.
False
Neonatal depression can have multiple causes beyond asphyxia.
What factors influence fetal to neonatal adaptation?
Maternal placental blood flow, blood pressure, maternal oxygenation
These factors are critical for a successful transition to extrauterine life.
What does the APGAR score assess?
Activity, Pulse, Grimace, Appearance, Respiration
It provides a quick assessment of the newborn’s health and response to resuscitation.
What are the phases of physiologic adaptation in a newborn?
First period of reactivity, sleep phase, second period of reactivity
These phases describe the newborn’s initial responses after birth.
What is the role of surfactant in the lungs?
Stabilizes the alveoli and prevents collapse
Surfactant is essential for maintaining proper lung function.
What happens to pulmonary vascular resistance (PVR) after birth?
It decreases significantly
This is due to lung aeration and increased oxygen levels.
What is the function of the ductus arteriosus?
Shunts blood from the right ventricle to the aorta
Equal in size to the aorta. Blood flows R to L because of high pulmonary vascular resistance and low placental resistance
It is a key fetal shunt that closes after birth.
Fill in the blank: The umbilical vein carries _______ blood from the placenta to the fetus.
oxygenated
This is crucial for fetal oxygen delivery.
What is a common cause of neonatal respiratory distress?
Surfactant deficiency
This can lead to conditions such as Respiratory Distress Syndrome (RDS).
What indicates a need for gavage feeding in newborns?
Choking/cyanosis with feeds
This may suggest esophageal atresia or other feeding difficulties.
What is the normal range for a newborn’s hematocrit?
45 – 65 gm/dl
This range is important for assessing newborn health.
What is the significance of the transition period in a newborn’s life?
Most dramatic changes occur in the first few minutes of life
This period is critical for establishing normal physiological functions.
What is the normal respiratory rate for a newborn?
40-60 bpm
This rate can vary with activity and state.
What is acrocyanosis?
Normal peripheral cyanosis in newborns
It is often seen in the first few hours after birth.
What are signs of illness in a newborn?
Respiratory distress, hypothermia, hypoglycemia
Early identification of these signs is crucial for intervention.
What are the mechanisms of heat loss in newborns?
Evaporation, Radiation, Convection, Conduction
Understanding these mechanisms helps prevent hypothermia.
What is the first sign of respiratory distress in a newborn?
Rapid, shallow breathing
This can indicate underlying respiratory issues.
What is motility?
The ability of the gastrointestinal tract to move contents through it.
What condition is characterized by a lack of stool?
Constipation.
What is an imperforate anus?
A congenital defect where the anal opening is absent or blocked.
What does tracheoesophageal fistula/esophageal atresia refer to?
A congenital condition where the esophagus is not properly connected to the trachea.
What is intestinal obstruction?
A blockage that prevents the normal flow of contents through the intestines.
What does NEC stand for?
Necrotizing enterocolitis.
What is the central nervous system?
The part of the nervous system consisting of the brain and spinal cord.
What characterizes a normal state of reactivity in a newborn?
Periods of reactivity, smooth state transition, and predominant flexor tone.
What does hypotonia indicate?
Decreased muscle tone.
What are signs of abnormal behavior in a newborn?
Hypotonia, lethargy, asphyxia.
What does IDM stand for?
Infant of a diabetic mother.
What is a normal urinary output in the first 24 hours for a newborn?
100% void with pale yellow urine.
What might the presence of urate crystals in urine indicate?
Normal hydration status.
What is acute tubular necrosis?
A condition resulting from damage to the tubules of the kidneys.
What is renal vein thrombosis?
A blockage of the renal vein due to a blood clot.
What is hydronephrosis?
Swelling of a kidney due to a build-up of urine.
What are posterior urethral valves?
Congenital obstructive membranes in the urethra.
What is a normal heart rate for a newborn?
80-140 bpm.
What indicates good perfusion in a newborn?
Blood pressure greater than 35-40 mmHg systolic and 2+ pulses bilaterally.
What are signs of abnormal cardiovascular function in a newborn?
Congenital heart disease, supraventricular tachycardia, shock.
What type of shock is characterized by low blood volume?
Hypovolemic shock.
What should you think when there is any change in behavior in a newborn?
Infection.
What are signs of poor skin perfusion in a newborn?
Irritability, lethargy, poor feeding, temperature instability.
Cord gas acidosis- umbi vein vs umbi arteries
Venous- acidosis on placental side
Arterial- acidosis on fetal side
FRC
Functional Residual Capacity
20 cc/kg at birth
Vaginal/thoracic squeeze/chest recoil assists the replacement of fluid with air to establish FRC
Increase in FRC with each breath
Less inspiratory pressure for subsequent breaths
Evaporation
Contact with cold or wet objects
Term Neonate: After birth, if not dried immediately, the amniotic fluid on the skin evaporates, causing heat loss.
Preterm Neonate: Preterm babies have immature skin with higher water loss, leading to significant evaporative cooling, especially in high-humidity incubators.
Radiation
Near a cold object, not touching
Term Neonate: Lying in a crib near a cold window or wall can result in heat loss through radiation.
Preterm Neonate: Radiant heat loss is significant in preterm infants when placed in an open warmer without adequate heating.
Convection
Contact with cold air
Term Neonate: A baby exposed to drafts from an open window or fan can lose heat through convection.
Preterm Neonate: Incubators without a proper temperature-controlled environment can cause heat loss if warm air is not maintained.
Conduction
Wet, damp linens
Term Neonate: Placing the baby on a cold examination table or scale can cause heat loss.
Preterm Neonate: A preterm baby lying on an unheated mattress instead of a warm skin-to-skin contact surface can experience significant heat loss.
