Test 1 Flashcards
When should you consider thrombolytic therapy for venous thromboemboli?
-Hypotension (clearest indication) -Severe hypoxemia -Severe RV dysfunction by echo -Anatomically very large PE (one lung or greater) Severe proximal DVT Essentially, use in hemodynamically unstable patients
What do you see on lung histology of an individual with hypersensitivity pneumonitis?
poorly formed granulomas
Where do pseudostratified ciliated columnar cells extend to?
extend to beginning of terminal bronchioles
Whats the equation for steady state CO2 excretion?
VCO2= VA x [PACO2/760]
Identify the accessory muscles of inspiration:
external intercostals sternocleidomastoid scalene
If the brainstem is transected between the Apneustic Center and the Pneumotaxic Center, the animal breathes with _____.
inspiratory gasps.
What separates the trachea from the esophagus?
tracheoesophageal septum
List the multiple effects of maternal carbon monoxide on fetal O2 delivery.
-lowers maternal O2 content -left shifts maternal dissociation curve so it doesn’t release O2 as well as it should at the placenta -this lowers umbilical venous PO2 -maternal CO diffuses into fetal circulation —CO competes with O2 for Hb binding sites –CO left shifts fetal dissociation curve making it harder for O2 to be delivered to fetal tissue
shipbuilder/insulation/ pipe fitter=
asbestosis
Post thrombotic syndrome develops in 30% of patients with DVT. What causes it?
damgage to venous valves
mediastinal lymphadenopathy, non-caseating granuloma=
sarcoidosis, fungal infection
Does a D-dimer level have high specificity or high sensitivity?
high sensitivity (if you have low D dimer levels, it’s pretty safe to say you don’t have a venous thromboembolism)
Where do neurogenic tumors (schwannoma, neurofibroma, ganglioneuroma) almost almays occur?
posterior mediastinum
What’s maternal venous blood PO2 and %Sat?
35mmHg, 70%
which medullary respiratory center is necessary for respiratory rhythm?
Pre-Botzinger complex
What are the key differences between usual interstitial pneumonia (idiopathic pulmonary fibrosis) and nonspecific interstitial pneumonia?
-NSIP patients are usually younger and shower a more stable pattern of chronic dyspnea (not progressive) - Radiographically, NSIP typically lacks peripheral honeycombing.
What can mom have that puts baby at risk for respiratory distress syndrome?
Maternal diabetes: high level of insulin can inhibit surfactant production
What diseases increase compliance work?
restrictive diseases
alveolar pressure > 0
expiration
Dynamic airway collapse takes place in intrathoracic airway during ____.
active expiration
What is the normal P50 in adult Hb?
26 mmHg (50% sat.)
In the fetal circulatory system, what site has the highest O2 saturation?
umbilical vein (80% sat)
What’s P50 of fetal blood on the dissociation curve?
Fetal P50 ~ 19 mm Hg vs 26 mm Hg for adult
What patient population does sarcoidosis particularly effect?
African American females (below 40, non-smokers)
What’s a normal FEV1/FVC value (percentage wise)?
80%
What is transudate and what causes it?
thin, clear, serous fluid only; results from a change in hydrostatic and/or oncotic pressures
What’s a typical value for lung compliance?
200ml/cm H20
What stimulates a baby to take its first breath?
asphyxia of birth, drop in temp, tactile stimulation
What is the PAO2 and PACO2 levels when VA/Q = infinity (no perfusion; dead space)?
Alveolar gas has PO2 and PCO2 of humidified inspired air.
What is a normal tidal volume?
500 ml
Equation for functional residual capacity:
FRC= ERV + RV
The larynx is Lined by “pseudostratrified ciliated columnar epithelium” everywhere EXCEPT the superior surface of the epiglottis and the true vocal folds, which are lined by ____.
lined by “stratified squamous non-keratinized epithelium”
In the intact brain, the Pneumotaxic Center _____ the Apneustic Center, and the normal function of the Apneustic Center is not well understood.
INHIBITS
What are the components of the conducting zone of the respiratory tree?
nose, pharynx, larynx, trachea, bronchi, terminal bronchioles
What’s a normal change in O2 content?
Δ O2 Content = 5 ml/100 ml (5 vol%)
Identify the accessory muscles of expiration:
internal intercostals abdominals
What are two random changes that take place at birth (he just slapped it on the last slide of an SDL)?
-a combined metabolic and respiratory acidosis (which is corrected) -a drop in body temp of about 3 degrees Fahrenheit (which is corrected)
birds/hot tubs/ farmers=
hypersensitivity pneumonitis
How do you get the total compliance of the system?
“add in the reciprocal” 1/Ctotal= 1/C lung + 1/C chest wall result is that your total compliance is always less than the individual compliances
What’s the equation to find the PO2 of alveoli?
PAO2= PiO2 - [PACO2/R]
R=0.8 PiO2= [atmospheric pressure- 47] x FiO2
FiO2 is .21 unless states otherwise
What’s used to treat venous thromboemboli acutely?
UFH or LMWH or Fondaparinux
Describe serum RBC changes in the first four months of life:
initially a drop in RBC count b/c increased PO2 shuts down erythropoiesis. Recovers after a few days.
Describe serum bilirubin changes in the first four months of life:
at birth, very little liver function= bilirubin builds up quickly; liver function develops shortly thereafter and bilirubin levels promptly drop
What structures compose the diaphragm?
-septum transversum -pleuroperitoneal membrane -dorsal mesentery of esophagus
What’s fetal umbilical arterial blood PO2 and %Sat?
22mmHg, 58%
In a tension pneumothorax, will the trachea deviate towards or away from the side of the lung collapse?
away from the side of the lung collapse (tracheas are cool with spontaneity, not tension)
What are the outcomes of oligohydramnios?
Potter’s syndrome -Positional deformities in limbs, joint stiffness, flexion contractures -Pulmonary hypoplasia -Flattened facial features (nose/ears)
Describe the epithelium of the nasal vestibule.
stratified squamous keratinized
What are the two main differences between the maternal and fetal dissociation curves?
1) fetal has higher affinity for O2 than adult Hb (left shift) —-b/c fetal has lower affinity for 2,3-BPG 2) there’s a higher concentration of Hb in fetal blood than in maternal blood
What’s a normal A-a gradient?
5-10mmHg
Which cells/mediators are involved in asthma?
mast cells, Th2 t cells, eosinophils
What’s the equation for change in O2 content (also called Fick’s principle)?
change in O2 content= VO2 / CO
VO2 is amount of O2 delivered to the tissue CO=cardiac output
What are the two types of emphysema? Which is the most common type?
centriacinar and panacinar centriacinar is the most common
What is the normal P50 for oxygen (PO2 that gives 50% saturation of Hb)?
=26 mmHg
What disease states increase lung compliance?
emphysema
normal aging (might as well be a disease)
What’s used for long term treatment/prevention of venous thromboemboli?
warfarin
What scan should be used to confirm PE?
spiral CT (unless patient has renal problems, in which case you give them a VQ scan)
Why does absorption (resorption) atelectasis happen more readily if someone is breathing a high O2 gas mixture?
normally, the N2 gas present in the alveoli slows the collapse of the alveoli. If high content O2 is breathed long enough, it washes out the alveolar nitrogen subsequently removing the protection from collapse that N2 provided.
What is used as an index of O2 level in a tissue?
venous PO2
Dynamic airway collapse takes place in extra thoracic airways during ____.
inspiration
If transpulmonary pressure (PA - Ppl) is increased, then lung volume is _____.
increased
What’s the treatment for sarcoidosis?
Tx is steroids, but they often resolve spontaneously without treatment
What’s the normal arterial PO2??
90-95 mmHg
stem cells of the bronchioles
club (clara) cells [are capable of dividing into ciliated or non-ciliated bronchiolar cells]
Rate of diffusion of O2 between air and blood is inversely proportional to ____.
thickness of barrier (distance from alveolar air to RBC)