Pulmonary Hypertension Flashcards
How is pulmonary hypertension
Increase in mean pulmonary arterial pressure greater than 25 mmHg OR 30 mmHg with exercise
What are the diagnostic classifications for pulmonary hypertension in neonates
Prenatal or developmental, persistent pulmonary hypertension of the newborn, pediatric heart disease, bronchopulmonary dysplasia, isolated pulmonary arterial hypertension, pediatric lung disease
What are the world health organization functional classification of pulmonary hypertension
Class 1: No limitations of physical activity, Class 2: slight limitations of physical activity but comfortable at rest, Class 3:marked limitations of physical activity but comfortable at rest, Class 4: symptoms at rest
What are the functional classifications for pulmonary hypertension in children
Class 1: Asymptomatic growing and developing normally with no limitation to activity, Class 2: slight limitation to activity with delayed developmental milestones while comfortable at rest, Class 3A: Marked limitation to activity with regression of learned physical activities with frequent naps compromised comfortability at rest, 3B: The growth is severly compromised with supplemental feelings required, Class 4: unable to do any physical activity and not able to interact with family
What are signs and symptoms of pulmonary hypertension
Low oxygen saturation, failure to thrive, lethargic, tachypnea, tachycardia, peripheral edema
What is the pathophysiology of PPHN
Failure to achieve normal drop in Pulmonary vascular resistance, decreased/dysfunctional endothelial nitric oxide synthase (eNOS)
What is the treatment for PPHN
Inhaled nitric oxide (dilates vessels in the lungs)/ prostacylcin anaglos or sildenafil
What is the pathophysiology in pediatrics
Relative imbalances of mediator substances that causes vasoconstriction, pulmonary vscular remodeling and thrombosis
What are mediator substances that are increased in pediatric pulmonary hypertension, decreased
Endothelin-1, thromboxane A2, endothelin 1/ prostacyclin and nitric oxide
What are the adjunctive therapies that can be used to treat pulmonary hypertension
oxygen, diuretics, and calcium channel blockers, vasopressors, sedation and NMBAs, warfarin
What are the potential therapies for pulmonary hypertension
inhaled nitric oxide (iNO), prostacyclin analogs, endothelian-1 antagonist, phosphodiesterase inhibitors
What is the MOA of prostacyclin
Bind smooth muscles in the vasculature causing vasodilation and anti-proliferation
What are the prostacyclin analogs duration
Epoprostenol treprostinil, Iloprost
What is the problem with using epopstenol in pulmonary hypertension
Continous IV infusion (requires long term central venous catheter), not selective and causes vast hypotension
What are other side effects
flushing headache nausea diarrhea tachycardia pain tachyphylaxis
What are the dosage forms of treprostinil, side effects
Continous subcutaneous infusion, continous IV infusion, inhaled dosage form/ pain and erythema upon injection site
Which is the most pulmonary selective, drawback
Iloprost, requires 6 to 9 inhalations
T/F: Endothelin 1 causes vasconstriction in the pulmonary vasculature depending on the receptor that is bound
True
Where is endothelian A receptors located, what do they cause
Smooth muscle cell/ vasoconstriction, proliferation, cell migration, hypertrophy
Where is endothelian B receptors located, what do they cause
Endothelial cells/ inhibition of endothelian 1 production, increased clearance of endothelian 1, increased production of nitrous oxide and PGI2, increased vaso-dilation and anti-proliferation
What are the endothelian 1 receptor antagonists
Bosentan and Ambrisentan
Which endothelian 1 receptor is contranindicated in pregnancy and has drug-drug interactions, what are the liver enzymes that cause interactions
Bosentan/ CYP2C9: warfarin and oral contraceptives, CYP3A4: ketoconazole, fluvastin, itraconazole
What is required for using Bosentan, what changes must be done due to this requirement
Monthly monitoring of LFTs/ If greater than 3 and less than 5 times the upper normal limit: lower the dose for discontinue and monitor every 2 weeks, If greater than 5 and less than 8 times the upper normal limit: stop the bosentan and monitor for two weeks (can re-consider), If greater than 8 times the upper normal limit: Stop bosentan and do not reintroduce
What is the pedatric dosing for bosentan
Less than 10kg: 1-2 mg/kg/dose, Greater than or equal to 10kg: 31.25 mg- 62.5 mg once or twice a day
