Pulmonary Edema Flashcards
What is pulmonary edema?
Accumulation of fluid in the alveoli
Pulmonary edema is usually d/t __________.
L-sided heart failure
What are some non-cardiogenic causes of pulmonary edema?
- Fluid overload
- Aspiration
- Smoke inhalation from fire
- IV drug abuse (especially narcotics)
How does IV drug abuse contribute to pulmonary edema?
They effect the brainstem and cause an increase in permeability
T or F:
Pulmonary edema causes a l/o compliance d/t decreased elasticity
F, there is l/o compliance, but this is d/t fluid in the alveoli not l/o elasticity
What is a specific characteristic of the cough that accompanies pulmonary edema/
The cough is productive, with frothy and possibly blood tinged sputum
What causes the dyspnea in pulmonary edema?
Inadequate filling and expansion of the lungs
What is the Tx of pulmonary edema?
- Treat the cause
- Respiratory support
What is an embolus?
Anything in the blood that should not be there
What is a pulmonary embolism?
An occlusion in the pulmonary arterial bed
What is pulmonary embolism usually due to?
DVT
- Pieces of the thrombus may break off and become emboli
What are some causes of pulmonary embolism, excluding DVT?
- Fracture
- Air
- Amniotic fluid
How does a fracture contribute to pulmonary embolism?
When the fracture occurs, damage is done to the surrounding vessels. Then marrow of the fractured bone is exposed and if the fat contained in the marrow get into the surrounding vessels this can cause a pulmonary embolism
How does amniotic contribute to pulmonary embolism?
Because the particulate matter from the fluid may become an embolis if it can gain access to the mum’s vessels
What are saddle embolus?
Large emboli the form in the bifurcation of pulmonary arteries. If an embolus settles there, a thrombus may form around it and can occlude the lumen. Quickly life-threatening.
Patho of pulmonary embolism:
Thrombus in artery -> embolus -> obstructs perfusion -> platelets aggregate and degranulate/release mediators -> cause bronchial and pulmonary constriction -> hemodynamic instability
What is hemodynamic instability?
Refers to the instability of the flow of blood
How does the nervous system react in a situation with pulmonary embolism?
Triggers bronchoconstriction due to reflex in the brain
How is the ventilation:perfusion ratio affected by a pulmonary embolism?
It will become unbalanced and result in hypoxemia
How is cardiac output affected by pulmonary embolism?
There is a decrease in cardiac output because the embolus is obstructing flow through the pulmonary circuit, making it more difficult to adequately pump the blood into the left side of the heart. Decreased blood in the heart = decreased cardiac output
T or F:
Pulmonary embolism causes a decrease in surfactant.
T
How can pulmonary embolism cause right sided heart failure?
Because of the embolus, the right side of the heart ends up pumping against significant resistance, causing hypertrophy and, eventually, death. DUN DUN DUNNN
What are the typical mnfts of pulmonary embolism?
(3)`
- Dyspnea
- Tachypnea
- Chest pain
Why does tachycardia happen during pulmonary embolism?
This is a compensatory mechanism, the increased heart rate will increase the speed of bloodflow and help to compensate for the decrease in oxygen.
What are 3 important labs to run for pulmonary embolism and why are they done?
- ABG’s
- Measures the acidity, or pH, and the levels of oxygen and carbon dioxide from an artery - D-dimer
- Measures for the presence of fragments of fibrin, broken down by fibrinolysis - Lactate dehydrogenase (LDH3)
- A lung specific enzyme
What is 131I-HSA and what is it used for?
- 131I is an isotope
- HSA is “human serum albumin”
- This test is a lung scan that will track the path of the 131I-HSA through the lungs until it reaches the obstruction
What kinds of imaging may be done to diagnose pulmonary embolism?
- Chest X-ray
- CT
- Angiogram
What is the treatment of pulmonary embolism?
4
- STAT intervention
- Maintain cardio-pulmonary support
- Eg drugs, O2, inc CO, etc
- Thrombolytics and anticoagulants
- Treat the cause
- Eg DVT
When does pulmonary HTN occur?
When there is a sustained pulmonary arterial pressure exceeding 25 mmHg (normal = 15 mmHg)
The pulmonary circuit is compliant because…
2
…it has low resistance and low pressure
If the CO is increased, this will have a _______ impact on pulmonary pressure.
Minimal
If resistance were to increase within the pulmonary circuit, what kind of effect would this have on the pulmonary pressure?
Pressure will increase
Most cases of pulmonary HTN are due to:
Existing problems of cardiac and pulmonary origin.
What are the 3 categories of pulmonary HTN?
- Hypoxemia
- Increased pulmonary venous pressure
- Eg mitral valve stenosis
- Increased pulmonary blood volume
- Eg septal defect
Mnfts of pulmonary HTN:
7
- Dyspnea
- Fatigue
- Syncope
- Chest pain on exertion
- Those of right sided failure
- Distended pulmonary arteries
- Seen on x-ray
- Right ventricle hypertrophy
- Seen on x-ray
What is the treatment of pulmonary HTN?
3
- Treat the cause
- Ca channel blocker
- Prostacyclin (PGI2)
- Used if other drugs fail
- Potent vasodilator
- Anti-platelet
