3 - Pulmonary Patho Flashcards
(148 cards)
What is dyspnea?
Subjective experience of breathing discomfort
Normal tidal volume
400-800 ml
Kussmaul respirations are characterized by: (3)
increased RR
Very large tidal volume
No expiratory pause
Cheyne-Stokes Respiration
Alternating deep and shallow breathing patterns with 15-60 seconds apnea in between
What causes Cheyne Stokes?
Any condition that slows the blood flow to the brainstem or impairs conduction above the brainstem
It basically indicates a delayed reaction to chemoreceptors
Minute volume =
Tidal volume x RR
What causes peripheral cyanosis?
Centra cyanosis?
Poor blood delivery to the periphery, but normal PaO2
Decreased PaO2
What amount of unsaturated hemoglobin causes cyanosis?
5g of Hgb
How can you reverse clubbing?
You can’t, even if you restore normal oxygen levels
What probably causes clubbing?
Megakaryocytes and platelt clumps escape filtration in the pulmonary bed
They enter the systemic circulation
They lodge in the tissues and release platelet-derived growth factor at the nail bed
Can also happen 2/2 inflammatory cytokins and growth factors released during cancer
What do V and Q represent?
V = amount of air getting into the alveoli
Q = among of blood perfusing the capillary
What is a normal V/Q?
Why?
0.8-0.9
perfusion is usually somewhat greater than ventilation in the lung bases
AND
bronchial venous blood (non-participating) is shunted into peripheral circulation
What is alveolar dead space?
Alveoli are ventilated but not perfused
What does it mean if a V/Q is high?
Ventilation outstrips perfusion
What is the most common cause of a high V/Q?
PE
What is the definition of Acute Respiratory Failure?
PaO2 < 50
AND/OR
PaCO2 > 50 with pH <7.25
What are the four most common causes of postop resp failure?
atelectasis
pneumonia
pulmonary edema
pe
Who is most at risk for primary/spontaneous pneumothorax?
Young men, usually smokers
What is the cause of primary pneumothorax?
Blebs in the visceral pleura rupture and create a conduit for air to get into the pleural space
No clear cause, but almost everyone who has it has emphysema-like changes to their lung, whether they smoke or not
Autosomal dominant inheritance
What kind of Pneumothorax or COPD pts prone to?
Why?
Secondary/traumatic
they have large vesicles in their lungs that can rupture
What are other words for transudative?
Exudative?
watery
proteinaceous
What is the usual cause of transudative pleural effusion?
Cardiogenic
Hypoproteinemia from kidney or liver disease
What is the usual cause of exudative pleural effusion?
infection, inflammation, malignancy
Caused by anything that releases biochemical mediators and increased capillary permeability
What is the usual cause of empyema?
Detritus of infection d/t blocked lymph vessels
pneumonia, lung abscess, infected wounds