7-9 Flashcards
- Pulmonary pathology in the neonatal period: Hyaline-membrane disease, aspiration syndrome, bronchopulmonary dysplasia.
- pulmonary pathology in the neonatal period
refers to diseases affecting the pulmonary system from birth to 28 days as respiratory distress
respiratory distress defiend as:
- tachypnoe less than 60 breaths a minute
- laboured breathing, with chest wall recession and nasal flaring
- expiratory grunting
- cyanosis
transient tachypnea of the newborn
- definition
- cause
- Is a benign self-limitid condition that can present in any infants of any gestational age shotly after birth
- it is caused by a delay in the clearance of fetal lung fluid after birth that leads to ineffective gas exchange, respiratory distress and tachypnea.
transient tachypnea of the newborn
- Etiology
- History and physical
- Delivery before completion of 39 weeks gestation, a cesarean section without labour, gestational diabetes, and maternal asthama
- tachypnea less than 60 breaths per minute, nasal flaring, grunting, intercostal/subcostal/supracostal retractions.
transient tachypnea of the newborn
- Evaluation
- Treatment
-complete blood count, blood culture, C-reactive protein, lactate to rule out neonatal sepsis
Arterial blood gas may show hypoxemia (less than 85mmhg) and hypocapnia - low carbondioxide in the blood.( pco2 less than 45mmhg)
-treatment is supplemental oxygen and rule of two, or CPAP
Hyaline membrane disease
-overview
-Also known as respiratory distress, and is the result of insufficient surfactant which is responsible for keeping the alveoli open
Hyaline membrane disease
-etiology
caused by lack of surfactant, surfactants is made by type 2 alveolar cells that produce a lipiprotein complex knows as sufractant
the mother starts producing surfactant around the 24th week of gestation, and it is a slow process in the start, but around the 34-35 th week of gestation when the mother stars producing cortisol is when the surfactant production increses.
-surfactant decreases the surface tension in the lungs by binding to the water molecules and not making them stuck on the bottom of the alveoli, thus decreasing the surface tension and making it easier for the alveoli to expand.
-Hyline membrane disease is a type of of hypoplasia ( a lack of cells in an organ or tissue) with type 2 alveolar cells failing to develop.
-premature birth
Hyaline membrane disease
- Diagnosis
- Treatment
diagnosis is usally via clinical picture tachypnea, tachycardia cyanosis, and x-ray will show decresed lung volume and ground glass infiltrates uniform through the lungs
ABG will show lowered amount of oxygen less than 85mmhg and increased amount of co2.
-treatment include oxygen supplementation, with CPAP with iv fluids and exogenous surfactant through the breathing tube into the lungs.
Aspiration syndrome
- general
- meconium
-also known as meconium aspiration, in which the fetus pass meconium in the amniotic fluid, where it can put itself in a risk of aspiration that can have serious consequences
-meconium is a thick green brownish, blackish, substance that makes up the fetal stool, and is made up of bile, bile acids, mucus, pancreatic fluid, blood and cellular debris.
meconium is usally not found in the amniotic fluid, instead its usally passed within the first 24.72 hours after birth.
Aspiration syndrome
- etiology
- diagnosis
- post term neonates less than 42 weeks of gestational age, umbilical cord/ plancetal pathology as they can put stress on the fetus in utero.
- staining of the amniotic fluid, the fetus has meconium stains, tachycardia, x-ray.
Aspiration syndrome
- complications 1-5
- treatment
complications include 1-5
- mechanical obstruction
- surfactant wash
- pneumonitis occurs in 50% of meconium aspiration, defined as inflammation of the airways due to irritants found in the meconium , leads to inflammatory response in the alveoli causing stifness and fibrosis.
- pulmonary vasoconstriction/pulmonary hypertension as meconium has vasoconstrictive properties.
- damage to umbilical cord by inflammation and fibrosis, widespread vasoconstriction that can lead to umbilical cord ischemia that can turn in umbilical necrosis.
- treatment includes mechanical ventilation and nitric oxide for vasodilation.
bronchopulmonary dysplasia
- generall
- etiology
-Infants who have an oxygen requirement at a postmenstrual age of 36 weeks are
described as having bronchopulmonary dysplasia (aka chronic lung disease).
Often a complication of Respiratory Distress Syndrome
-the lung damage is due to delay in lung maturation and possibly from pressure and volume trauma from atrifical ventilation.
-has a multifactoral etiology, significant risk factors include prolonged mechanical ventilation, high concentrations of inspired oxygen and infections
bronchopulmonary dysplasia
- symptoms
- treatment
- symptoms include rapid breathing, labored breathing, wheezing, repeted lung infections
- the focus of the treatment is to minimize further lung damage and provide support to the infants lung allowing them to heal and grow.
- diuretics: decrease the amount of fluid in alveloi.
- bronchodilators: relax muscles around air passage
- cortical steroids: reduce inflammation within the lungs
- cardiac medications: relaxing the blood vessles around the lungs and reduce the strain on the heart.
Infections of the neonatal infant:
- common causes
- ealry symptoms of infections
neonatal infections can be acquired during prenatal development or the first four weeks of life
-preterm infants are at an increased risk of infections as IgG is mostly transferred across the placenta in the first trimester, additionally infections around the cervix is often a cause of preterm labor and may cause postpartum infection. such infections are called congenital infections
-common causes include toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus, varcicella zoster, syphilis and others.
when the infection is intrauterine we can see growth restrictions and infants deformities.
-early symptoms of infections include: respiratory distress with transient apnea, lethargy, increase in liver and spleen size, WBC can be both elevated or decreased.
Infections of the neonatal infant: neonatal sepsis,
-general
Sepsis is the bodys response to a systemic infection, sepsis can be early onset or late onset.
sepsis can be confused with bacterimia, bacterimia is defined as the presence of bacteria in the blood, while sepsis is the response to the bacteria.
-the response include vasodilation leading to hypertension leading to tachycardia.
-sepsis is casued usally to a primary infection somwhere else in the body, which makes sepsis a complication of the primary infection.