Pulmonary Flashcards
What is the extra lobe on the right side?
The middle lobe
How many generations of airway branches are there in humans? Which are the conducting ones?
23
The first 16 are conducting airways
The lungs develop out of the _________
Gut tube
What are the 5 stages of lung development?
Embryonic - foregut endoderm extends into surrounding mesenchyme. Branching occurs to level of subsegmental bronchi.
Pseudoglandular/terminal sac - branching to level of terminal bronchioles.
Canalicular - branching to level of respiratory bronchioles. Surfactant begins to be made. Fetal begins to practice breathing.
Saccular - terminal sacs form. Characterized by epithelial cell differentiation (type I and II pneumocytes)(
Alveolar (continues until age 3) - alveoli mature
The maximal force for the diaphragm is at ______ it’s resting length
130%
How are compliance and elastance related?
They are inversely proportional
At what fetal age is surfactant produced?
Fetal week 24
The probability of tubulent flow is given by the ______
Reynolds number
What are the 2 types of pulmonary ventilation?
Minute - volume of air that goes into or out of the lung in 1 minute
Alveolar - volume of air that flows into or out of the alveolar space in 1 minute
minute > alveolar b/c it encompasses more of the lung
What are the 2 dead spaces in the lung? What dead space do they combine to form?
Anatomic - air that remains in the conducting path
Alveolar - alveoli that are in unperfused areas in the lung
Physiologic dead space
What is different about lungs in obstructive diseases?
Increased resistance
What is the ratio between O2 in and CO2 out?
They are equal, so 1-1 ratio
What are the lobes of the lung?
R = superior, middle, inferior L = superior, inferior
What is the acinus?
The terminal bronchiole, alveolar ducts, alveoli - the region of lung supplied with air from a terminal bronchiole
Which germ layer do the lungs develop from?
Embryonic endoderm
Which week do lung buds develop at?
4
Which branchial arches do the lungs develop between?
4th and 6th (remember there is no 5th)
The formation of conducting airways is completed at the end of the _________ stage of lung development
Pseudoglandular
Do they pulmonary veins grow out of the LA or do they come to it?
They grow from the pulmonary vascular bed to the left atrium
What is an atresia?
When an orifice or passage in the body is abnormally closed/absent
In lung development, the descent of the lungs is halted by the _________
Liver
Is branching in the embryonic stage of lung development symmetrical?
No. More on the R
Are most alveoli present at birth?
No. 90% of them develop after birth
The pulmonary arteries develop from the __________ aortic arch
6th
What are the following lung volumes? TGV RV TLC FVC FEV1 DLCO
Thoracic gas volume Residual volume Total lung capacity Forced vital capacity in 1 second Forced expiratory volume uhh some measure of gas exchange
Is total ventilation affected by moderate disease conditions?
No. Generally, total ventilation is affected only by severe disease conditions
How does gravity affect ventilation and volume throughout the lung?
Ventilation of the top alveolus volume bottom
This is because of compliance - bottom alveolus in middle of PvsV curve; top alveolus is at top
What is compliance?
dV/dP
How do you calculate minute ventilation?
Tidal volume * breathing rate
Usually about 6 L
Our breathing rate/tidal volume is where it is because of the superposition of 2 types of work:
Resistance (increases with decreasing tidal volume b/c big breaths open airways)
Elastic (increases with increasing tidal volume)
Breathing parameters reduce total work
What are the 2 pleura?
Parietal - on inside of chest wall
Visceral - on outside of lung
What are the cartilagenous air conduction pathways in the lung?
Trachea
Primary bronchi - 1R;1L
Secondary (lobar) bronchi - 3R;2L
Tertiary (segmental) bronchi - 10R;8L
Where are the pulmonary arteries? Where are the veins?
Arteries follow bronchial tree
Veins are intersegmental
What is the blood supply of the bronchi? Where does it go?
Bronchial artery. Most of it anastomoses with the pulmonary supply and some goes back to the bronchial vein
What are 4 cell types in the bronchial epithelium?
Ciliated cells - move mucus up airway
Goblet cells - secrete mucus
Basal cells - stem cells for ciliated and goblet cells. These are shorter.
Neuroendocrine cells of varying types - reflexive control of airway diameter
What are 4 layers to the mucosa of the bronchus?
Epithelium
Basal lamina
Areolar connective tissue/lamina propria - loose connective tissue with capillaries an dleukocytes
Muscularis mucosa - agitate epithelium, helps submucosal glands excrete mucus
What are 3 layers to the submucosa of the bronchus?
Dense connective tissue
Cartilage plates with chondrocytes living in their lacunae
Adventitia - large blood vessels, nerves
___________________ connects to the points of the C-shaped cartilage rings in the trachea
Trachealis muscle
What are 2 cell types in the bronchiolar epithelium?
Club cells - secrete surface-active substances (like surfactant but not) that maintain patency of the bronchioles since the bronchioles don’t have cartilage plate support like bronchi do
Ciliated cells - move mucus up airway
What are 2 cell types in the alveolar epithelium?
Type I pneumocyte - they chill
Type II pneumocytes - secrete surfactant. Stem cell for type I and II pneumocytes
What is Dalton’s Law?
Inspired O2 = (atmospheric pressure - H2O partial pressure)* fraction oxygen being given
PiO2 = (760 Torr-47 Torr)*FO2
PB = barometric pressure
FO2 is 0.21 with normal breathing; 1 w/ 100% oxygen
What is the alveolar gas equation?
alveolar PO2 = inspired PCO2 - arterial PO2/0.8
PAO2 = PIO2 - (PACO2/R)
R = respiratory exchange ration = CO2 produced/O2 consumed. Can vary depending on metabolite. Usually 0.8
What is the rate-limiting step for removing CO2 from the blood in teh lungs?
Ventilation
Diffusion is fast
What is the alveolar ventilation eqation?
PaCO2 = (rate VCO2/rate VA) * k
rate VCO2 = CO2 production in 1 minute
rate VA = alveolar ventilation in 1 minute
How is the length of the diaphragm affected in obstructive lung disease?
It is shorter b/c their lungs don’t relax all the way.
As a consequence, force exerted by the diaphragm is less
Dras the lung pressure vs. volume curve
:)
What is lung compliance like in emphysema?
Increased, so elastic recoil of the lungs is decreased. Expiration is impaired.
3 causes of reduced chest wall compliance
Old age
Obesity
Scar tissue
3 affects of water surface tension on the lung if surfactant wasnt there
Wants to make the alveolus smaller -> collapse of alveoli, decreasing surface-volume ratio
Decreased lung compliance
Water accumulation in lung
Where in the lungs is the majority of airway resistance?
Bronchioles
How do airway resistance and radius relate?
R oc 1/r^4
Where in the lungs can turbulent airflow be found?
The trachea (sometimes)
2 ways the body can induce bronchoconstriction
Parasympathetic input
Histamine
2 ways the body can induce bronchodilation
Sympathetic input
CO2 in bronchioles (which isn’t really the body doing something on purpose)
Why does higher lung volumes decrease resistance?
Increased radius of bronchioles
Why do patients with emphysema exhale through pursed ips?
Increases airway pressures, reducing airway collapse
3 factors that affect perfusion
O2 tension (hypoxic vaso-pulmonary constriction)
Capillary recruitment
Gravity
What is ventilation?
What is perfusion?
Ventilation (V) = air that reaches alveoli
Perfusion (Q) = blood that reaches the alveoli
How do V?Q ratios in the apex vs. base of lung compare?
The base of the lung has a lower V/Q ratio because ventilation and perfusion are increased at the base compared to the apex, but Q is more so
Apex of lung V/Q>1 ; wasted ventilation
Base of lung V/Q
Does V/Q mismatch affect arterial CO2 levels? What about O2?
No
Yes
2 ways the body corrects V/Q mismatch
Bronchodilation with high PCO2 in bronchiole
Vasoconstriction with low PO2 in blood
What is an area with perfusion but no ventilation?
Shunt
What is an area with ventilation but no perfusion?
Dead space
What is the most common mechanistic cause of hypoxemia?
V/Q mismatch
pneumonia, PE, COPD, etc
The conversion of CO2 to carbonic acid is catalyzed by _________ in _________
Carbonic anhydrase
Red blood cells
The effect of O2 binding reducing CO2 binding to hemoglobin and vice versa are the _____________ and _________ effects
Haldane (O2 binding reduces CO2 affinity for Hb)
Bohr (CO2 binding reduces O2 affinity for Hb)
What is the oxygen carrying capacity of the blood (definition)?
Maximal O2 that can be carried by a particular amount of Hb
What is the A-a gradient?
A measure of the difference between the Alveolar and arterial oxygen concentration (PAlvO2-PartO2)
We want it to be low
Helps find source of hypoxemia. If A-a is abnormal, problem is in the lungs
How is compliance in an alveolus with a large volume?
It is not so great compared to a smaller one (see pressure-volume curve)
How does FEV1/FVC compare between obstructive and restrictive lung disease?
Obstructive - less than normal b/c it is hard to exhale
Restrictive - greater than normal b/c lung volumes are reduced
What is the Henderson-Hasselbach equation
pH = pKa + log[A-]/[HA]
What is pH?
-log[H+]
3 intracellular buffers
organic phosphates
proteins
hemoglobin
4 extracellular buffers
proteins
albumin
phosphate
bicarbonate
3 stages of the bicarbonate buffering system
H2O + CO2 H2CO3 H+ + HCO3-
normal venous pH
7.4
How does pH of oxygenated and deoxygenated blood compare? Why?
Deoxyhemoglobin is a great buffer! venous pH is only slightly lower and venous pCO2 is only slightly higher than arterial blood despite there being much more CO2
What are the 2 compensation mechanisms for disturbed blood pH?
Lungs regulate CO2 levels (minutes)
Kidneys regulate bicarbonate (hours-days)
What is the most common cause of respiratory acidosis/alkalosis?
Changes in ventilation
Acidosis - too little ventilation
Alkalosis - too much ventilation
2 categories of metabolic acidosis. What are their causes?
Anion gap: Na+ - (Cl- and HCO3-). When Na»anions, indicates extra acid from somewhere being balanced by HCO3 reduction
Non-anion gap - from loss of bicarbonate
3 causes of non-anion gap metabolic acidosis
GI losses (like diarreha)
Renal losses
Too much IV saline (increases in Cl- with loss of bicarbonate)
8 causes of metabolic acidosis
MUD PILES
Methanol Uremia DKA (and other ketoacids like EtOH and starvation) Propylene glycol INH (isoniazid antibiotic) Lactate Ethylene glycol Salicylates
5 causes of metabolic alkalosis
Loss of gastric acid (vomiting or NG tube suction)
Ingestion of a bicarbonate
Ingestion of an alkali
Hypovoluemia (contraction alkalosis)
Diuretics
What part of the brain contains motor neurons that control respiratory muscles?
Medulla
3 things that peripheral chemoreceptors look out for
Low arterial O2
High arterial PCO2
High arterial [H+]
Where are the peripheral chemoreceptors?
Carotid bodies
Where are central chemoreceptors?
ventral surface of medulla
What do central chemoreceptors sense?
Protons in CSF, which correlates with arterial CO2
Do the peripheral or central chemoreceptors have more power to mediate the ventilatory response?
Central
How does the kidney control pH?
By altering amount of H+ secretion, which is proportional to bicarbonate (HCO3-) reabsorption
so, the kidney decreases bicarbonate reabsorption in alkalosis so it can keep more H+ ions
What are the 3 different types of normal breath sounds?
Vesicular
Bronchovesicular
Bronchial
Bronchiovesicular and bronchial sounds heard over the periphery of the lung are abnormal
Rales sound like ______
Velcro
Are wheezes more commonly heard on inspiration or expiration?
Expiration
Rhonchi sound like _____
Rumbles
What is the difference between a lung volume and a lung capacity?
Capacities are the sums of at least 2 volumes
Can you directly measure lung residual volume?
No
What is functional residual capacity?
The volume of gas remaining in lung at end of a tidal expiration
ERV + RV
Expiratory reserve volume + residual volume
At which volume is the lung system in equilibrium?
end of a tidal breath - functional reserve capacity
What is inspiratory capacity
Volume of gas that can be maximally inspired from a normal exhale
TV + IRV
What is vital capacity?
ERV + TV + IRV
What is total lung capacity?
RV + ERV + TV + IRV
Can you diagnose restrictive disease with spirometry?
No
the FEV1/FVC can be normal!
Draw the flow-volume loop of the lung
Mrr
Inspiration is symmetric
Expiratory limb has an increase in airflow at the beginning
Draw the flow-volume loops of fixed, variable intrathoracic, and variable extrathoracic obstructions
:)
2 ways to measure lung volumes
Dilution w/ gas that won’t be readily absorbed like helium - requires uniform diffusion of gas
Plethysmography - uses Boyle’s law and pressure changes in a small volume to look at lung volume
What is boyle’s law
P1V1 = P2V2
How do we measure DCLO?
Transfer of a known (but small) amt of CO to blood
What do you need to correct for in DLCO testing?
Alveolar volume
DLCO/VA
What are 2 terms used to describe respiratory muscle strength?
PiMax
PeMax
Inspiration/expiration against a closed valve
3 reasons the bicarbonate buffer is so important
High concentration
Blood pH is close to pK (where curve is steepest)
Can be affected by both kidneys and lungs (most effect)
FRC and ________ are equivalent terms
TGV (toral gas volume)
At what lung capacity are elastic and resistance work minimized?
FRC (functional residual capacity)
How do you calculate minute ventilation? Alveolar ventilation?
Vm = Vt*RR
Va = (Vt-Vd)*RR
How do you calculate pulmonary vascular resistance?
R = dP/CO
CO is in L/min so is flow
4 categories of obstructive lung disease
Chronic bronchitis
Emphysema
Asthma
Bronchiectasis
Why is the lamina propria important?
It allows leukocytes to wander around in it
4 causes of hypoxemia (4 for the 2nd one)
Altitude
Hypoventilation (obesity, central, neuromuscular, drugs)
Diffusion limitation (exercize, interstitial lung diseae)
Low V/Q or shunt
Thromboxane is a vaso______
Constrictor
Prostacyclin is a vaso_______
Dilator
6 inflammatory cells found in asthmatic airways
Mast cells Eosinophils Th2 Dendritic cells Macrophages Neutrophils
3 structural airway changes in asthma
Increase in airway SMCs
Increase in blood vessels
Increase in mucus secretion form increased goblet cells and size of submucosal glands
Do sympathetic neurons have much power in ditermining airway diameter?
Nope. It’s mostly parasympathetic neurons
What element do we use to treat asthma?
Magnesium in life threatning exacerbation
Bronchodilates maybe due to inhibition of calcium influx into SMC
4 short-acting beta-adrenergic agonists (SABAs)
Albuterol
Terbutaline
Pirbuterol
Levabuterol
2 long-acting beta-adrenergic agonists (LABAs)
Salmeterol
Formoterol
Are anticholinergics used in COPD or asthma? What is their suffix? What do they do?
COPD
-tropium
Bonchodilate via SMC relaxation
Inhibit production of respiratory secretions
What are the actions of systemic glucocorticoids?
What respiratory issue are they given for?
Inhibit phospholipase -> inhibit cytokine synthesis
-> anti-nflammatory, vasoconstrict (reducing edema)
Use to treat acute exacerbations of asthma
Can you use LABAs by themselves for asthma treatment?
No - can increase deaths
Should be combined with an inhaled corticosteroid to control inflammation
What do leukotriene modifiers due?
Inhibit 5-lipoxygenase
Bronchodilate
Anti-inflammatory due to leukotriene blocking
What is omalizumab?
What is it used for?
Anti-IgE
Allergic asthma
What is mepolizumab?
Anti-IL-5, which is a cytokine
Why is lung infacrtion uncommon?
Collateral circulation from bronchial arteries
What is the source of most bleeding in the lung?
Bronchial circulation (not pulmonary)
How does the compliance of pulmonary vessels compare to systemic ones? What are 2 results of this?
Much more compliance
-> low resistance, high volume vascular bed
Does lung resistance go up when cardiac output increases? 2 reasons
No
Lung vessels are highly distensible
The number of perfused vessels increases
What are the 3 West zones of the lung?
Zone 1: Palveolar > P arterial > Ppulmonary veins
Minimal blood flow
At apex
Zone 2: Parterial>Palveolar>Pvenous
Intermittent blood flow
At middle
Zone 3: Parterial > Pvenous > P alveolar
Constant blood flow
At base
Locations can change with position, but in upright individual are like this
4 safety factors to prevent pulmonary edema
Decreased interstitial oncotic pressure
Increased interstitial hydrostatic pressure
Increased plasma oncotic pressure
Lymphatic reserve system
2 mechanisms for pulmonary edema
2 ways you can destinguish
Hemodynamic (or hydrostatic or cardiogenic) from increased pulmonary hydrostatic pressure
Permiability (or non-hydrostatic or non-cardiogenic) from acute widespread injury to microvascular circulation
History/exam
left atrial pressure (from pulmonary capillary wedge pressure). If it is low, this means it is not hemodynamic
What are the 5 categories of pulmonary hypertension?
What are the 2 other ways to categorize pulmonary hypertension?
Pulmonary arterial Due to left heart disease Due to lung disease/hypoxia Thromboembolic Idiopathic/unclear/multifactorial
Pre-capillary (arterial)
Post-capillary (venous)
Which gorup of people does idiopathic pulmonary arterial hypertension tend to affect?
Younger women
4 targeted pathways for medical management of pulmonary arterial hypertension
Endothelin pathway - endothelin receptor antagonists (endothelin is a vasoconstrictor)
Nitric oxide pathway - inhibiting phosphodiesterase (braks down NO)
Prostacyclin pathway - prostacyclins vasodilate
Calcium channel blockers - for those with an acute reponse to a pulmonary vasodilator (5% of the time)
The pulmonary vasodilating effects of nitric oxide are mediated through its second messenger, ______________
cGMP (grump)
_______________ degrades cGMP
Phosphodiesterase
Prostacyclins upregulate ______________
cAMP
4 drug categories to reduce airway tone in asthma
Beta-agonists
Anti-cholinergics
Leukotriene inhibitors
Methylxanthines (theophylline) - phosphodiesterase inhibitors that increase intracellular cAMP
3 drug categories to reduce inflammation in asthma
Corticosteroids Mast cell stabilizers Leukortriene inhibitors Anti-IgE (omalizumab) Anti-IL5 (mepolizumab)
What defines COPD?
Irreversible airflow limitation
What defines chronic bronchitis?
Productive cough present for 3 months/year over a 2-year period without another identified medical cause
What defines emphysema?
Abnormal, permanent enlargement of air spaces distal to terminal bronchioles
+
Destruction of alveolar walls w/o obvious fibrosis
2 subtypes of emphysema. What causes each?
Centriacinar - smoking
Scarring and focal dilation of broncioles and adjacent alveoli
Panacinar - alpha1 anti-trypsin deficiency (autosomal recessive)
Bronchioles down to alveoli involved
What is bronchiectasis?
Abnormal dilation of proximal medium-sized bronchi due to destruction of muscular and elastic components of their walls
They produce shit-tons of sputum
Cystic fibrosis is a mutation in what gene?
Cystic fibrosis trans-membrane regulator
The ascultatory hallmark of bronchiolotis is _____
Inspiratory squeak
2 major causes of airflow obstruction
Airway narrowing (bronchospasm, plugging, inflammation)
Floppy airways (decreased radial tethering or decreased airway integrity)
2 types of asthma. Which one tends to be more chronic/persistent?
Extrinsic (allergic)
Intrinsic (nonallergic). More chronic/persistent
What is bronchoprovocation? What is it for?
Give methacholine/histamine and test FEV1
Can detect occult asthma
What is the PV curve like in acute asthma?
Above (higher volumes) but same shape (no change in tissue properties)
How do you differentiate vocal cord dysfunction from asthma? (3)
Sounds on inspiration (stridor)
Fiberoptic laryngoscopy
Bronchoprovacation may worsen VCD, but does not change FEV1 or PC20
What is vocal cord dysfunction (in pulmonary setting)
Inappropriate vocal cord motion results in airflow obstruction
How many people have COPD after 50 years of smoking?
20
What is the mechanism of dynamic airway collapse in emphysema?
Reduced elasticity of tissue around airways so can’t withstand pleural pressure
What is the PV curve like in emphysema?
High volume Steeper curve (because more compliant/less elastic)
5 causes of death from COPD
Respiratory failure Right ventricular failure Pneumonia Spontaneous pneumothorax Pulmonary embolism
How do you get bronchiectasis?
A combination of:
Infectious/inflammatory insult
Impaired drainage/obstruction/immunodeficiency
3 parts to management of bronchiectasis
Airway clearance to remove secretions
Antibiotics
Treatment of reactive airways disease
Well controlled asthma frequency: Daytime symptoms Nighttime symptoms SABA Peak flow Oral steroid Urgent care visit
2x/week 2x/month 2x/week Normal 1x/yr 1x/yr
What is tiotripium for?
A long-acting anticholinergic for asthma in ppl >12
What does cromolyn/nedocromil do?
Inhibit mast cell mediator release
Preventative therapy for exercise-induced or allergen-induced asthma
What does theophylline do?
Inhibits phosphodiesterase
-> bronchodilation and some anti-inflammatory activity
What are the effects of particle size on drug inhalation?
> 5um deposit in pharynx and larger airways
What has the greatest capacity to influence the natural history of COPD?
Smoking - so everybody should stop
Is physical activity recommended in COPD?
Yes! Exercise is important
What is the pressure difference across the lung?
Pulmonary artery pressure - left atrial pressure
Where are the lymphatic vessels in the lungs?
Intralobular, with the veins
What causes hydrostatic pulmonary edema?
Increased pulmonary capillary wedge pressure
What pressure defines pulmonary hypertension?
Mean pulmonary artery pressure >25 mmHg
What is V=IR for the lungs?
Pulmonary arterial pressure = CO * resistance
What is the gold standard diagnostic for pulmonary embolism?
Angiogram
Rarely performed though
In which chest Xray projection can the heart appear enlarged?
AP
What does the silhouette sign show on Xray?
2 structures of similar density in contact (like lung-heart border)
What is atelectasis?
Regions of lung collapse
What is the spine sign on CR?
Spine becomes less radiolucent as we move downswards because th elung is filled with something more dense instead of air.
How does the P-V curve change in restrictive lung disease?
It decreases, because compliance is decreased
Note that if cause of restriction isn’t lung tissue itself, compliance won’t chnage
What 2 things characterize interstitial lung disease?
Inflammation
+
Scarring
5 treatment options for interstitial lung disease
Remove offending expore (if possible) Immunosupression (if necessary) Drugs (nintedanib, pirfenidone for idiopathic pulmonary fibrosis) Oxygen Transplantation
What is idiopathic pulmonary fibrosis?
A scarring lung disease with pattern of injury of usual interstitial pneumonia
So IPF if clinical
UIP is from pathology
Where in the lung is idiopathic pulmonary fibrosis usually?
Peripheral and basilar
What is the difference between usual interstitial pneumonia and nonspecific interstitial pneumonia on pathology?
IPF: spatially and temporally heterogeneous fibrosis w/ fibroblasts. Fibrotic and normal lung are seen right next to each other
NIP: temporally homogenous fibrosis with varying degrees of inflammation and fibrosis
What are the 2 smoking-related ILDs that are on a spectrum? How do you treat them?
Respiratory bronchiolitis
Desquamative interstitial pneumonia
Stop smoking
What characterizes pulmonary langerhans cell histiocytosis? Who gets it? How do you treat it?
New smokers
Cysts and nodules mostly in upper lobe
Stop smoking
What characterizes organizing pneumonia?
Plugs of granulation tissue and fibrosis distal to bronchioles
Imaging: ground glass and consolidation that may be migratory
How do you treat organizing pneumonia?
6-12 months of steroids
How do you treat acute and chronic eosinophilic pneumonia?
Steroids
What causes lymphangioleiomyomatosis (LAM)? What characterizes it?
Mutation in tuberous sclerosis genes
Get cysts and nodules, peribronchovascular proliferation of SMCs
What characterizes sarcoidosis?
Systemic noncaseating granulomatous disease
What are the 2 parts of the physiologic state of anxiety? What parts of the brain are involved in each?
Conscious feeling - mediated by cortex, cingulate cortex, frontal lobes
Emotional states - mediated by autonomic, endocrine, somatic responses involving the amygdala, mypothalamus, brainstem
What are the 2 components of anxiety?
Cognitive
Physiologic state of hyper-arousal
What 2 things are the biological basis of panic disorder?
Dysregulation in the noradrenergic system/excess norepinephtine
Dysregulation of GABA
3 hypotheses for panic dosorder
CO2 + lactate hypersensitivity due to chronic hyperventilation
False suffocation alarm - brainstem alarm is too sensitive
Hypersensitive limbinc system
2 changes in chronic bronchitis. What is the primary involved cell?
Squamous metaplasia (allow epithelium to be tougher) Mucus gland hypertrophy
At what point do you say something is bronchiectasis?
When airway diameter > vessel diameter
What happens in constrictive/obliterative bronchitis?
Airways scar shut
What defines diffuse alveolar damage?
Inflammation of alveolar septa
How do you tell if a hemorrhage is not from biopsy? (3)
More blood
Iron-containing macrophages in airspaces
Fibrous ribbons of septa
Where are neutrophils in acute bronchitis?
In wall and airway
Nonnecrotizing granuloma menas what 2 diseases?
Sarcoid/beryllium
What is the difference in location between smoking and alpha-1-antitrypsin deficiency emphysema?
Smoking - upper lobes, around airways
Alpha-1-antitrypsin - lower lobes, panlobular
3 symptoms of B cell tumors
Fever
Weight loss
Drenching night sweats
3 risk factors for primary spontaneous pneumothorax
Men
Smokers
Familyhistory
6 symptoms of pneumothorax
Acute onset chest pain Dyspnea Cough Anxiety Cyanosis Respiratory distres
Somehow these are different than PE
What is the difference between a bulla and a bleb?
Bulla - enlargement of lung tissue
Bleb - enlargement of visceral pleura
What is a tension pneumothorax
Intrapleura pressure > atmospheric pressure at least during expiration (sometimes inspiration in addition)
Decreases venous return, limits cardiac output
Medical emergency
What do you do in event of a tension pneumothorax?
Do not wait for a CXR
Insert a chest tube to deflate
What’s the difference between transudate and exudate?
Transudate - from increased hydrostatic pressure
Exudate - from increased permeability. So has more proteins, LHD, cells
3 drugs used for smoking cessation
Nicotine
Bupropion (Wellbutrin) - inhibits reuptake of dopamine and norepinephirine, reduces weight gain, reduces depression
Varenicline - partial agonist at nicotine receptor; also blocks nicotine binding
How do you measure the pressure volume curve clnically?
Insertion of an esophageal pressure monitor. This is a surrogate for pleural pressure
What serum value is increased in sarcoidosis?
ACE
What is dysphonia?
Where is the defect?
Alteration of voice quality. Usually a laryngeal source
What is dysarthria?
Where is the defect?
Alteration of rhyrhm, enunciation, articularion
Neurological or muscular source
What is stertor?
Where is the defect?
A snoring sound from nose, nasopharynx, throat
When should a patient see an otolaryngologist?
If hoarseness last longer than 2 or 3 weeks
2 materials vocal fold cysts can be made out of
Blood
Mucus
2 materials vocal fold polyps can be made out of
Blood
Fibrous tissue
How do you treat vocal fold hemorrhage and tears?
Strict voice rest
Does COPD risk and lung cancer risk correlate?
Yes!
As COPD worsens, lung cancer risk is increased
What are the 3 subtypes of non small call lunc cancer?
Squamous cell carcinoma - bronchial epithelium
Adenocarcinoma - mucus glands
Large cell carcinoma (like the others)
What is the cellular origin of small cell carcinoma?
Bronchi
4 symptoms of undiagnosed lung cancer
Cough
Anorexia
Weakness
Weight loss
How do you typically treat small cell lung cancer?
Drugs: cisplatin, etopiside
How do you typically treat non-small cell lung cancer?
Surgery
Also chemotherapy/radiation with surgery - adjuvant and neoadjuvant therapy
What are the 2 types of apnea?
Central - respiratory effeorts are absent
Obstructive
In pneumonia what does infectious agent sputum indicate? Minimal sputum?
Bacteria
Atypical bacteria or viral
All patients with suspected pneumonia should have which 4 diagnostic tests?
CXR
CBC
Complete metabolic panel
Blood gas/pulse oximetry
________ is produced by parynchymal cells in response to bacterial toxins
Procalcitonin
Indicates there is an infection in lung or intestine, where the parynchemal cells live
4 groups who shoud get pneumococcal vaccine
Immuncompromised people
>65
Chronic illness
Asplenia
What are the 3 main subtypes of afferent nerves within the vagus nerve that regulate cough?
Rapidly adapting receptors
Slowly adapting stretch receptors
C-fibers
RARs, SARs respond to mechanical stretch
C-fibers respond to chemical stimuli
4 phases of the cough reflex
Inspiratory phase (glottis open)
Compressive phase (glottis closed)
Expiratory phase
Relaxation phase
Time frame for acute, subacute, chronic cough
8 weeks
5 causes of chronic cough in adults
Upper airway cough syndrome Asthma GERD Non-asthmatic eosinophilic bronchitis Neuropathic cough
What is the mechanism of upper airway cough syndrome?
Cough receptors stimulated by secretions from nose or sinuses
What is non-asthmatic eosinophilic bronchitis?
Eosinophilic airway inflammation like asthma but without variable airflow limiatation or airway hyperresponsiveness
Antagonists of which 3 bronchial smooth muscle receptors cause bronchoconstriction?
Muscarinic
Leukotriene
Histamine
What is the main drug you give for anaphylaxis
Epinephrine
The common cold’s symptoms are mostly explained by release of ________ inflammatory mediators
Bradykinin
3 effects of muscarinic receptor block
Sedation
Prevention of nausea and vomiting
Block of secretions
4 organisms that cause atypical pneumonia
Legionella
M. Pneumoniae
C. Pneumoniae
C. psittaci
What 7 things can fill the alveoli?
Poor funny boy can’t piss for crap
Pus, fluid, blood, cells/cancer, protein, fat, calcium
Influenzavirus variation is due to 2 types of envelope glycoproteins:
Hemagglutinin
Neurominidase
2 classes of antivirals we use to treat influenza and 2 examples of each
Neurominidase inhibitors (oseltamivir, zanamivir)
Adamantanes (amantadine, rimantidine)
3 defenses against upper airway collapse
Upper airway recruitment threshold (stimuli needed for upper airway dilator muscle response)
Loop gain (amt of ventilatory response to stimuli)
Arousal threshold (for negative pressure)
What is cheyne-stokes respiration?
Hypercapneic respiratory drive results in overshooting of PaCO2 below apneic threshold
So, an oscillatory pattern of apnea and hyperpnea
3 most common mutations in adenocarcinoma
KRAS
EGFRT
EML4-ALK
Which 2 nerves go to the larynx? Where does it come from?
Superior laryngeal nerve
Recurrent laryngeal nerve
From vagus nerve
What are the 2 parts of the superior laryngeal nerve?
Internal - sensatibon
External - motor (to upper crycothyroid)
Which respiratory phase is stridor heard in?
Inspiratory
Expiratory
Biphasic
What is the mechanism of croup?
Subglottic narorowing
Reinke’s edema is seen in what patient population?
Female smokers
How long does it take for an ACE-inhibitor cough to stop after the drug is stopped?
1-7 days usually
But up to month
How do you calculate the A-a gradient?
What is PalveolarO2 usually?
Palveolar O2 - P arterial O2
P alveolar O2 is about 102 mmHg if ventilation is good
How do you tell if respiratory pH changes are acute or chronic?
For every 10 mmm change in PaCO2
- 08 pH change in acute
- 03 pH change in chronic
What is winters formula?
1.5*bicarb + 8 +-2 = expected pCO2
This is how you can tell if the person is appropriately responding to a metabolic pH change
How do you determine if there is not additional nonanion gap acidosis?
18+(normal bicarb + observed bicarb) = 22-26
OR the difference is between 4 and 8?
Do antihistamines reduce inflammation?
Apparently not
How do degcongestants work?
Stimulation of alpha1-adrenergic receptors
-> constriciton of nasal blood vessels
What are 3 topical decongestants?
Pheynylephrine
Oxymetolazine
Xylometolazine
3 drugs you give in combo to reduce symptoms of the common cold
1st gen antihistamine
Decongestant
Naproxen - blocks inflammation
What is more helpful than taking expectorants?
Increasing fluid intake
Using a cool mist/steam vaporizer
What is the expectorant we care about? What does it do?
Guaifenesin
Decreases viscocity of respiratory tract secretions
What is the defect in primary ciliary dyskinesia (immotile ciliary syndrome)?
Dyenin arms
What is the most common immune cell in the pulmonary airspace?
macrophages (90-95%)
Smoking increases which immune cell in the lung?
Macrophages
Which signalling molecule suppresses inflammation of macrophages in the absence of PAMPs? What binds it?
SIRP-a
Collectins
Surfactants are also called ________ because of their immune responsibilities in the lung
Collectins
3 types of secreted pattern recognition receptors in the lungs that serve as bridges between PAMPs and their spcific receptors
Collectins
Complement
Pentraxins
3 types of cellular pattern recognition receptors
Toll-like receptors
Svacenger receptors
C-type lectin receptors (lectins are carb PAMPs)
How does collectin binding change during inflammation in the presence of pAMPs?
It goes from binding SIP-a to binding PAMPs directly and this allows them to bind inflammatory receptors (instead of inhibitory receptors)
What cell type does mycobacterium tuberculosis live in?
Macrophages
What is the calcified lung nodule marking the initial site of TB infection called?
Ghon complex
What is a Ranke comples?
A Ghon complex + calcified regional lymph nodes
How do you read a TB skin test?
After 48-72 hours, measure the diameter of induration (not erythema)
What are the 3 groups of criteria for a positive TB skin test?
Depends on risk for TB reactivation
> =5 mm Immunocompromised, old TB, recent contact with active TB
> =10 mm Immigrants from certain places, homeless, diabetes, dialysis, etc
> =15 mm all low-risk people
What populaitons do tuberculosis skin test false-negatives occur in?
T-cell depleted people
AIDS
Immunosuppression
Chemo
Old people
What 2 populations does tuberculosis skin test calse positivity occur in?
BCG vaccinated
People infected with envirionmental mycobacteria
How do TB blood tests work?
Take blood
Add TB antigens
Measure amount of IFN-Y
Quantiferon measures this with ELISA
T-spot measures this with antibodies
Why might immigrants get active TB well after moving? What are 2 advantages they lose?
Reduced vitamin D b/c lots of people go to dark places
Vitamin D suppresses growth of TB in macrophages
Induces expression of cathelicidins, which can kill TB
2 drugs we use to treat latent TB infection
isoniazid
Rifampin
Combined for 3 months
OR isioniazid for 9 months
OR rifampin for 4 months
Major side effect of isonizaid
Hepatitis
So don’t use in people with liver problems
4 causes of hypoxemia
V/Q mismatch
Impaired diffusion
Alveolar hypoventilation
Low inhaled O2 (high altitude, other)
3 things to always do inevaluation of respiratory failure
PHysical exam
Chest imaging (first CXR)
Arterial blood gas
What is FIO2 at room air?
0.21
What is barometric pressure at sea level or denver
760
630
What is PH2O
47
Without positive end expiratory pressure on a ventilaro, what can happen?
Atelectasis b/c lungs can keep deflating since the glottis doesn’t close like in normal breathing
Can ARDS be explained by cardiac failure or fluid overload?
Not fully
What is the time frame for ARDS development?
Occurs within 1 week of known clinical insult or worsening in respiratory symptoms
What part of the lung is inflamed in ARDS?
Alveoli
How do you describe alveolar edema in ARDS?
Proteinaceous
What sort of deposit forms in ARDS?
Hyaline membrane (from protein deposition)
What is the ONLY therapeutic intervention that improves survival in ARDS?
Ventilator
But important to limit pressure
Allow hypercapnea
Consider putting patients prone
3 major determinants of site and severity of occupational lung disease
Dose (duration*concentration)
Solubility
Particle size
Rounded atelectasis is from _____
Asbestos exposure
How does acetoazolamide reduce altitude sickness?
Increases bicarbonate loss
3 things in treatment of HACE
Oxygen
Descent
IV dexamethosone
Do people with HAPE also get AMS?
Sometimes - predispositions are different
What causes HAPE?
Pulmonary hypertension in response to acute hypoxia44An overexuberant response
What 3 drugs are given for HAPE?
Pulmonary vasodilators: nifedipiene, tadalafil
Increases clearance of water out of alveoli - salmeterol
How is airflow afected in diving?
Resistance and distance b/c of of tubing and outhpiece increases-> increase in work of breathing
What causes nitrogen narcosis?
Breathing of compressed air at >100 ft
B/c nitrogen acts as a narcotic
What is the biggest risk foractor for tuberculosis activation?
HIV
2 basic types of ARDS
Hypercapneic (too much CO2)
Hypoxic (too littoe O2)
What are the 4 variable parameters on a ventilator?
Oxygenation:
FIO2
PEEP (positive end-expiratory pressure)
Ventilation:
Respiratory rate
Tidal volume
What 4 things are altered in ARDS?
Timing within 1 week of a known clinical insult or new/worsening respiratory symptoms
CXR bilateral opacities not explained by other causes
Origin of edema not fully explained by cardiac failure/fluid overload
Decreased oxygenation
5 most common causes of ARDS
Sepsis Pancreatitis Trauma Aspiration Transfusion
Is ventilator use better prone or supine?
Prone, apparently
What is pneumonconiosis?
Dust-related lung disease leading to inflammation and scarring
_____ is the most common cause of occupational asthma
Isocyanates
If you see adult onset asthma, you should look for_________
An occupational source
Isocyanates are associated with what behavior?
Paints
If you see pleural plaques you should think _________
Asbestos exposure
Which 2 lung cancers are central?
Squamous cell carcinoma
Small cell carcinoma
What color is small cell carcinoma on H&E?
Blue
If you see a lung that looks kind of like millet, you should think_____
Active TB
Are kids nose or mouth breathers?
Nose (so congestion is a big problem!)
Irritant asthma is also known as ______
RADS 9(reactive airways dysfunction syndrome)
What are the 2 types of asthma caused by occupational exposures?
Immunologic - latency
Irritant/RADS - no latency
What is the difference in mechanisms caused high and low molecular weight compounds in by occupational immunologic asthma?
MW - specific IgE reaction
LMW - combine with endogenous proteins to create new antigenic determinants
How do pulmonary pressures change with hypoxia?
Increase from vasoconstriction
Is HACE part of AMS?
Yes. It is severe AMS with significant brain problems
3 drugs used for AMS
Dexamethosone - decreases brain edema
Acetazolamide - bicarb wasting ->metabolic acidosis -> hyperventilation
Ibuprofen
First 2 are used to TREAT AMS
3 signs of respiratory distress in infants
Lethargy
Poor feeding (b/c it’s the most active thing they do)
Grunting
Signs and symptoms of upper airway obstruction. 1 regular airway obstruction, 3 severe
Stridor
Drooling
Dysphagia
Dyspnea/distress
What is the most comon cause of chronic stridor?
Laryngomalacia
When the epiglottis blocks the airway
What is malacia?
Abnormal tissue sofening
In terms of pulmonology, it means collapse of part of the airway
What is clinically associated with a recurrent wheeze, a hoarse cough, and recurrent illnesses?
Tracheobronchomalacia
What is the narrowest point in the airway of adults? Children?
Glottis (vocal cord part)
Cricoid
5 things for Ddx of acute stridor
Croup (laryngotracheobronchitis) Bacterial tracheitis Epiglottiitis Laryngeal foreign body Scalding
What is the most common form of acute airway obstruction in children?
Croup
What does bronchioloitis sound like on ascultation?
Polyphonic wheezes in lung fields
2 results of bronchopulmonary dysplasia
Decreased surface area
Thickened interstitium
What 3 things does the H1 histamine receptor do?
Vasodilation
Increased capillary permeability
Cramping of gut smooth muscle
What is the difference between 1st and 2nd generations of antihistamines?
1st - H1 and other receptors
2nd - pretty selective for H1
What is the difference between NE and epi’s actions on blood vessels?
NE - vasodilation
Epi - vasoconstriction
4 side effects of antihistamines
Sedation
Antimuscarinic action - dry mouth, urinary retention, constipation
Paradoxical exitation
Postural hypotension
Topical decongestants stimulate which receptors?
Alpha-1
Does dextromethorphan depress respiration or predispose to addition?
No
Which drug is for robotripping? Which receptor does it act on?
Dextromethorphan
NMDA glutamate receptors
Where is inspiration on the PV hysteresis curve? Expiration?
Inspiration - right
Expiration - left
Catbon dioxide is a broncho______ and a vaso______
Bronchodilator
Vasoconstrictor
Medical intervention for stridor at rest due to croup?
Epinephrine nebs
Medical intervention for epiglottitis?
Intubation - it is a medical emergency
What are 3 differences between child and adult chest walls?
Weak intercostal muscles Horizontal ribs (no bicket handle) Diaphragm is flat
At what age can children perform spirometry?
6 usually
Which children are not likely to grow out of asthma by age 12? (2)
Allergic
Family history of asthma
What is empyema?
Purulent pleural effusion
Bronchopulmonary dysplasia represents the consequences of lung injury caused by what 3 things on the susceptible, immature lung?
Oxygen toxicity
Barotrauma
Inflammation
What is the newborn screening test for cystic fibrosis?
Immunoreactive trypsin levels (elevated in newborns with CF)
Which 3 blood vessel receptors cause vasodilation?
Muscarnic
Histamine H1
Bradykinin
Which receptor suppresses the cough reflex?
Mu opioid
Which 2 receptors result in pain?
Bradykinin
Histamine H1
What drug class is Loratidine?
Second generation antihistamine
2 receptors you can block to reduce motion sickness
How do they work in pregnancy?
H1
Muscarinic
They are safe to use in pregnant people
What is the mechanism of action of mucolytics?
Split disulfide linkages between mucopriteins, decreasing their viscocity
Also antioxidants
What chemical are mucolytics?
N-acetyl cysteine
Where is the cough reflex controlled in teh brain?
Medulla
What effect does low fluid volume have on pH?
Alkalosis
What is the mechanism of action of zyleutin?
It is a methylzanthine for treating asthma
Inhibits 5-lipoxegenase -> leukotriene block -> bronchodilation
What is the main toxicity of zyleutin?
Hepatotoxicity
Is sarcoidosis restrictive or obstructive?
Restrictive
What is the difference between redand grey pneumonia?
Red - looks like a liver on CT. Has RBCs, fibroblasts, neutrophils.
Frey - when RBCs start dying
What drug class is diphenhydramine?
First generation antihistamine
Benadryl!
Does histamine have much of a role in colds?
No
Mast cell mediators have a minor role in viral respiratory infections
What is a side effect of phenylephrine?
Irritation
What drug class do you use to treat upper airway cough syndrome?
1st generation antihistamine
