09: Lungs & Heart Flashcards
Right atrial pressure?
2-8mmHg
Right ventricle pressure?
15-30/2-8mmHg
Pulmonary artery pressure?
15-30/4-12mmHg
Pulmonary capillary wedge pressure?
2-10mmHg
Left atrial pressure?
2-10mmHg
Left ventricle pressure?
100-140/3-12mmHg
Aortic pressure?
100-140/60-90mmHg
Describe the blood flow distribution of the lungs
Uneven; in upright position, Zone 1 has lowest flow and Zone 3 has greatest.
In the supine position, blood flow is uniform.
Describe pulmonary circulation.
- Low resistance, high compliance vascular bed
- Reacts differently to stimuli (e.g., hypoxia) than does systemic circulation
- Normally in a state of mild vasodilation
Describe pulmonary circulation during exercise.
- ↑CO (4-5x baseline levels)
- Accommodated by recruitment and vasodilation
- Net effect: ↓PVR
What causes high-altitude pulmonary edema?
- At high altitude, ↓O2 –> hypoxia
- Hypoxia –> vasoconstriction of pulmonary bed
- Causes abnormal ↑PA pressure and ↑PVR
- Reversal rapid by going to lower altitude or O2 administration
Describe pulmonary venous hypertension.
- Post-capillary
- PA pressure >/= 25mmHg (rest) or >/=30mmHg (exercise), AND
- PCW/LVED pressure >15mmHg
Describe pulmonary arterial hypertension.
- Pre-capillary
- PA pressure >/=25mmHg (rest) or >/=30mmHg (exercise)
- PCW/LVED pressure =15mmHg
- Pulmonary vascular resistance index (PVRI) >/=3
- No left-sided ehart disease
What are etiologies of PVH?
- Valvular heart disease
- Cardiomyopathies
- Ischemic heart disease
- Pericardial disease
- Tumors (myxoma)
- Congenital (cor triatriatum, coarctation)
What factors influence microvascular fluid exchange in the lungs?
Net difference between **hydrostatic **and protein oncotic pressure and the **permeability **of the capillary membrane.
Describe a normal chest X-Ray.
PCWP: 8-12mmHg; lower lobe vessels 2-3x larger in diameter than upper lobe vessels.
Describe a chest X-Ray of pulmonary vascular redistribution (cephalization).
PCWP: 12-18mmHg; blood flow redirected to upper lobes; patient may be asymptomatic.
Describe a chest X-Ray of pulmonary interstitial edema.
PCWP >18mmHg; haziness of vessels, Kerley B lines (linear markings at periphery of lower lung fields), Sx: SOB, PND, orthopnea, cough.
Describe a chest X-Ray of pulmonary edema.
PCWP >25mmHg; alveolar edema with opacification of the air spaces, butterfly pattern around the hila, pleural effusions; Sx: cyanotic, rales and wheezing, frothy pink sputum, marked distress.
