respiratory distress syndrome and pulmonary HTN Flashcards
What are the pathologic changes seen in pulmonary HTN?
atherosclerosis of the pulm trunck, smooth muscle hypertrophy of pulm arteries, and intimal fibrosis. may also see plexiform lesions with severe long-standing disease (group/tuft of capillaries that appear together)
What is the classic presentation of pulm htn?
exertional dyspnea
Who may get primary pulm HTN?
young adult women
familial forms are related to inactivating mutations of BMPR2. this mutation causes proliferation of vascular smooth muscle.
What is the pathogenesis of ARDS?
damage to the alveolar capillary interface within the air sacs. protein-rich fluid leaks into the air sac and is reorganized as a hyline membrane. you will see pink hyline membrane in each air sac. this causes 2 problems: decreased gas exchange causes hypoxemia and cynosis. Also, they increase the surface tension of the air sac- diffuse collapse of the lung.
What are the X-ray features of ARDS?
diffuse white-out of the lung
What kinds of damage occur to cause ARDS?
activation of neutrophils induces protease-medaited and free radical-mediated damage of type I and type II pneumocytes
What is the treatment of ARDS? complications?
address underlying cause, give PEEP ventilation. recovery may be complicated by interstitial fibrosis. you have damaged the type II pneumocytes- you are having difficulty with regeneration.
What is the cause of neonatal respiratory distress syndrome?
resp distress due to inadequate surfactant levels. surfactant is produced by type II pneumocytes to reduce the surface tension of the lung so that the lungs don’t collapse every time you breathe out.
What are the clinical features of neonatal respiratory distress syndrome? What is seen on x-ray?
incr. resp effor after birth, tachypnea with use of accessory muscles, and grunting. cyanosis and hypoxemia also present. see diffuse granularity of the lung.
What conditions are associated with neonatal respiratory distress syndrome?
- prematurity. screen with L:S ratio (lecithin: sphingomyelin in amniotic fluid). Ratio > 2 means the lung is OK. (phosphatidylcholine is the major component)
- C-section delivery: steroids increase production and release of surfactant. C-section babies don’t have as much stress during birth and thus release less steroids
- Maternal diabetes: high blood sugar goes into baby, who responds with excess insulin. insulin inhibits production of surfactant
What are complications of neonatal respiratory distress syndrome?
hypoxemia incr. risk for persistence of a PDA and necrotizing enterocolitis (decr. O2 to gut). supplemental O2 can cause incr. free radicals. this can cause blindness as free radicals damage the retina, or bronchopulmonary dysplasia because of damage to the lung.
What is the treatment for neonatal respiratory distress syndrome?
maternal steroids before birth; artificial surfactant for infant
What is the definition of pulmonary HTN?
pulmonary artery pressure greater than 25 mmHg at rest
What is obesity hypoventilation syndrome?
obesity causes hypoventilation. We see decreased PaO2 and increased PaCO2 during waking hours.
What conditions may be distinguished by fremitus? What conditions may be distingished by tracheal deviation?
deviation towards the side of the lesion suggest atelectasis (lung collapse); away from the side of the lesion is a tension pneumothorax. consolidation, like with lobar pneumonia or pulm edema, will cause increased fremitus. everything else causes decreased fremitus.
