Path 2 - Resp 3

drraythe's version from 2016-04-10 23:40


Question Answer
**What is Atelectasis? What are the 2 types?Meaning empty alveoli which do not contain air
Can be congenital or acquired
**What are 2 reasons for CONGENITAL (present at birth) Atelectasis?(1) Obstruction of airways due to meconium, aspirate, amniotic fluid
(2) Hyaline Membrane Dz (foals & piglets)
**What are 2 reasons for AQUIRED Atelectasis?(1) Compressive (pneumothorax, hydrothorax, bloat, neoplasm) (outside of lung)
(2) Obstructive (exudate, parasites, neoplasms, foreign material) (Inside of lung)
**What is the gross appearance of Atelectasis?The lung tissue in Atelectasis is dark red, flabby & depressed below the surface of surrounding lung
No air inside!
*What is the microscopic appearance of Atelectasis?Microscopically, the alveolar walls are congested & are in close opposition
*What is Emphysema? What are the 2 types?There is air trapped in the tissues
2 types are alveolar & interstitial
*Explain what is going on in Alveolar Emphysema? Gross appearance?Excessive air in the alveoli, czing abnormal & permanent enlargement of alveoli w/ destruction of alveolar walls
Emphysematous areas are raised, pale or white, dry & can be easily compressed w/ finger. It usually alternates areas of Atelectasis
*What is the cz of Alveolar Emphysema?It develops under the pressure of inhaled air → due to incompletely obstructed bronchioles
***Explain the difference in the bronchioles btwn Atelectasis & EmphysemaIn Atelectasis, there is NO AIR & the bronchioles are completely obstructed (FYI there are 3 types: Resorptive (complete blockage), Compressive (alveoli cannot open due to comression pressure from pleural cavity, ie: hydrothorax), Contractive (fibrotic changes, ie scarring))
In Emphysema, there IS AIR & bronchioles are incompletely obstructed (Alveoli are miss-shapen from dmg, but can still open & fxn a little)
***Explain Interstitial Emphysema. How does it appear grossly?Air collects in the connective tissue of lungs:
Interalveolar septa
Interlobular septa
Below the pleura around the bronchi & blood vessels
- Septa becomes thick, shiny, filled w/ bubbles
- Violent/traumatic type of Emphysema
*Who gets Interstitial Emphysema the most & why?Mostly seen in cattle, bc of developed interlobular septa & lack of collateral ventilation in adjacent lobules
*What are the 3 conditions which cz Interstitial Emphysema?Forced respiratory efforts, seen in following conditions:
(1) When death is followed by violent efforts in anoxia (Attempted CPR)
(2) During quick loss of blood in trauma, slaughter of fully conscious animal
(3) Death after protracted illness (air going in, animal is weak/sick, cant expel the air)
What is the most commonly encountered pulmonary abnormality?Pulmonary Edema
**What are the 2 types/czs of Pulmonary Edema?NON-INFLAMMATORY: Czd by factors that ↑ capillary hydraulic (formerly hydrostatic) pressure
INFLAMMATORY: Czd by factors that ↑ permeability of the air-blood barrier
*What are some factors that ↑ capillary hydraulic (formerly hydrostatic) pressure czing Non-Inflammatory Pulmonary Edema? (3)(1) ↑ left atrial pressure in left sided or bilateral cardiac failure (cardiogenic edema)
(2) Excessive fluid transfusion (Fluid therapy overload)
(3) Pulmonary venous occlusion
*What are some factors that ↑ permeability of the air-blood barrier czing Inflammatory Pulmonary Edema? (4)(1) Inhalation of corrosive gases - SO2, Cyanides, smoke (dmg to epithelial cells)
(2) Infectious agents (mycoplasma, viruses) (dmg to endothelial cells)
(3) Systemic toxins (dmg to endothelial cells)
(4) Anaphylaxis in certain species like the horse & cow (dmg to epithelial cells)
Which species can have Pulmonary Edema from anaphylaxis & why?Horses & cows, bc for them fluid pools in the lungs instead of the portal system. Dmgs epithelial cells.
What are the gross lesions of Pulmonary Edema?Lungs are wet, heavy & do not collapse when thorax is opened. Interlobular septa is edematous & distended. Foam & mixed fluid present in trachea & bronchi. Clear, colorless or slightly yellow or turbid blood mixed fluid Which oozes out from cut surface of the lung. Color of edema fluid varies depending on the type of edema. (clear if non-inflam, inflam will be turbid & maybe blood)
**Whats the prognosis of Pulmonary Edema?Poor/Grave, it is usually fatal
*Acute Respiratory Distress Syndrome (ARDS) → why does this happen? (3)Bc of diffuse alveolar dmg…. Due to:
(1) Systemic dzs
(2) Direct injury to lungs
(3) Lesions in other organ systems, like sepsis, multiple trauma, extensive burns & pancreatitis
***Explain the pathogenesis of ARDS (Acute Respiratory Distress Syndrome)Systemic dz/direct injury/lesions like sepsis, multiple traumas, extensive burns, pancreatitis → diffuse alveolar dmg & this triggers a large amt of macrophages to be released → they release a large amt of cytokinesCytokines prime neutrophils stationed in the lung capillaries to release enzymes & free radicals → Which czs diffuse endothelial/epithelial dmg → permeability edema → accumulation of inflammatory cells, formation of hyaline membrane & fibrosis, all of which results in Pulmonary edema
How does ARDS (Acute Respiratory Distress Syndrome) present clinically?Sudden onset of severe dyspnea
What are the 5 main lesions of ARDS (Acute Respiratory Distress Syndrome)?(1) Diffuse damage to alveolar wall epithelium &/or endothelium
(2) Congestion & Edema
(3) Hyaline Membrane Formation
(4) Alveolar Epithelial Hyperplasia
(5) Interstitial Emphysema
Which cells in the alveoli are responsible for healing/repairing emboli?Type II Pneumocyte
**Pulmonary hypertension → due to a what?An ↑ in pulmonary vascular resistance
Almost always 2⁰ to something else
What are 3 reasons there would be an ↑ in pulmonary vascular resistance leading to pulmonary hypertension?(1) Vasoconstriction of pulmonary arterioles: mostly hypoxic (high altitude - brisket dz), chronic bronchitis or bronchiolitis (equine heaves)
(2) Vascular obstruction: thromboemboli including Dirofilaria immitis, arteriosclerosis, pulmonary vasculitis
(3) Vascular volume overload: fluid therapy overload
Pulmonary hypertension is almost always 2° to what 2 things?Cardiac dzs & lung dzs
**What are some cardiac dzs which lead to 2° pulmonary hypertension? (3)(1) Left sided heart failure
(2) Septal defects such as Mitral Insufficiency or Stenosis, Subaortic Stenosis, Cardiomyopathy
(3) Left to right shunt - Ventricular Septal Defect, Patent Ductus Arteriosus
What is a lung dz which can lead to 2° pulmonary hypertension?Chronic Interstitial Pneumonia w/ fibrosis & occlusion of pulmonary vessels
**Sustained pulmonary hypertension results in??↑ pressure load to right ventricle w/ compensatory *right ventricular hypertrophy* & ultimately Rt CHF
Inflammation of lungs is?Pneumonia, Pneumonitis
What are 3 ways inflammation of the lungs (Pneumonia, Pneumonitis) can be classified?Etiological
Based on site & pattern of lesion spread
What are the 2 morphological classifications of Pneumonia (lung inflammation)Exudative (produces an exudate (exudes cells) in response ot injury)
Proliferative ( ↑ in # of cells in response to injury, usually reticuloendothelial macrophages)
What are the 4 classifications Based on site & pattern of spread of lesions of Pneumonia?(1) Bronchopneumonia
(2) Interstitial Pneumonia
(3) Embolic Pneumonia
(4) Granulomatous Pneumonia
**Infectious Bronchopneumonia occurs when...The risk factors tip the balance: Exposure, crowding, dehydration, other infxns & chronic dz.....**STRESS!!*
Bronchopneumonia starts where & ends where?Origin of lesion in terminal bronchi (there is no defense system there) & it moves into the alveoli
**What are the 2 main TYPES of CZS of Bronchopneumonia?(Aerogenous route)
(1) Bacteria & Mycoplasma
(2) Aspiration of feed & gastric contents
Hepatization of lungs is what & occurs in what condition?When the lung kinda looks/feels like a liver instead of a lung & this occurs in BRONCHOPNEUMONIA
What do gross & microscopic lesions of Bronchopneumonia depend on?The stage of the dz
What are the 4 stages of Bronchopneumonia?(1) Stage of congestion
(2) Stage of red hepatization
(3) Stage of grey hepatization
(4) Stage of resolution
**Which dz has a CRANIO-VENTRAL distribution in the lungs?BRONCHOPNEUMONIA
What is the distribution of Bronchopneumonia in the lungs?CRANIOVENTRAL
**What are the 2 TYPES of Bronchopneumonia (& their alternative name)(1) Suppurative/lobular (suppurative is usually lobULAR) resolves in a week
(2) Fibrinous/LOBAR (fibrinous is usually lobAR)
4 possible reasons for restrictions of Bronchopneumonia to cranioventral part of the lung are...(1) Shortness & abrupt branching of bronchus
(2) Gravitational sedimentation of the exudate
(3) Deposition of infectious agent in the 1st bronchus
(4) Regional differences in ventilation
*Bronchopneumonia is irregular consolidation of___region of lungCranioventral
Which viral infxn can cz a cranioventral pattern of Bronchointerstitial Pneumonia, mistaken easily for Bronchopneumonia?Viral infxn by Bovine Respiratory Syncytial Virus
Lesions of Bronchopneumonia can be czd by what 2 bacteria? Which lobes are affected?Actinobacillus pleuropneumonia & Actinobacillus suis
Affect middle & caudal lobes
Which 2 species can have Bronchopneumonia that is cranioventral, but ALSO a patchy distribution throughout the lung tho it is not common?Cat & dog
Which dz has a "mosaic" appearance?Suppurative Bronchopneumonia
**SUPPURATIVE Bronchopneumonia → where in the lungs is affected? What kinda exudate? What’s the pattern like? How would you describe the appearance of it?CRANIOVENTRAL part of lungs. Suppurative OR mucopurulent exudate. LobULAR in pattern, w/ a MOSAIC appearance (w/ red & grey color)
How does Suppurative Bronchopneumonia appear microscopically?Neutrophils, macrophages, cell debris in alveoli & lumen of air passages
In who is recovery from Suppurative Bronchopneumonia delayed & WHY?In ruminants & swine, bc of lack of collateral ventilation
What are 4 major complications of Suppurative Bronchopneumonia?(1) Death by toxemia & hypoxia
(2) May cz metastatic abscesses in other organs
(3) May become chronic
(4) Plugging of bronchi & resultant atelectasis
Which type of Bronchopneumonia can → Atelectasis & why?SUPPURATIVE Bronchopneumonia, bc it can cz plugged bronchi → Atelectasis
What is the exudate like in Fibrinous Bronchopneumonia?Predominant exudate is more fibrinous than neutrophilic
**Which type of Bronchopneumonia results from more severe injury bc of strong pathogens?FIBRINOUS bc it is LOBAR (affected entire lobes)
***What are 3 STRONG pathogens in CATTLE which can result in Fibrinous Bronchopneumonia?M. hemolytica (Pneumonic Pasteurellosis)
Mycoplasma mycoides subsp mycoides
Hemophillus somnus
**What are 2 STRONG pathogens in PIGS which can result in Fibrinous Bronchopneumonia?P. multocida
Actinobacillus pleuropneumoniae
**What are 2 STRONG pathogens in sheep/goats which can result in Fibrinous Bronchopneumonia?M. hemolytica
M. mycoides subsp mycoides (latter mainly in goats)
Which dz has a "marbled" pattern?Fibrinous Bronchopneumonia
Where do things tend to accumulate in Suppurative Bronchopneumonia? Fibrinous?SUPPURATIVE: Alveoli & tertiary bronchiole
FIBRINOUS: Pleural surfaces, septa, alveoli & thoracic cavity
What are the 3 major lesions of Fibrinous Bronchopneumonia?(1) Severe congestion, hemorrhages & exudation of fibrin which accumulates on pleural surfaces, septa, alveoli & thoracic cavity
(2) Accumulation of fibrin in interlobular septa gives a lung typical marbled appearance
(3) The inflammatory responses are more severe than Suppurative Pneumonia. Foci of coagulative necrosis encapsulated by connective tissue (sequestrum) are common
Foci of coagulative necrosis encapsulated by connective tissue (sequestrum) are common in what dz?FIBRINOUS Bronchopneumonia
Which type of Bronchopneumonia RARELY resolves?Fibrinous (→ contractive type of atelectasis)
WHY is death more frequent in ___ Bronchopneumonia?Fibrinous Bronchopneumonia. Death is more frequent due to Pleuritis & Pericarditis. Fibrinous adhesions of pleura & pericardium is common sequel
Necrosis w/ formation of pulmonary sequestra is common in which Bronchopneumonia?FIBRINOUS
What is fibrin an index for in Fibrinous Bronchopneumonia? How quickly does fibrin develop?Amount is an index of degree of alveolar-capillary membrane dmg. Its a VERY ACUTE CHANGE
What are some predisposing czs for Aspiration Pneumonia?Any cz of dysphagia or regurgitation inclding pharyngeal paralysis & megaesophagus
Distribution of lesions in Aspiration Pneumonia depends on what 3 things?Nature of material
Bacteria carried w/ it
Distribution of material in lung
WIDESPREAD distribution of Aspiration Pneumonia is seen w/ what types of things that were aspirated? How does it appear grossly & histologically?Seen w/ liquid gruel or inhaled milk. Gross appearance is not characteristic. Histologically acute bronchiolitis & alveolitis is seen
When will you see a localized lesion in Aspiration Pneumonia? What are the lesions like?A localized lesion is w/ plant material, including whole grain & in pigs in dry season mostly w/ dusty dry particulate food. Lesions are discrete foreign body granulomas, lobar pneumonia or gangrene
Aspiration of vomitus in simple stomach animals is dangerous bc why? What can develop from this?Bc of edema development, long standing cases can develop into Fulminating Bronchopneumonia
What’s Fulminating Bronchopneumonia & when do you see it?A quickly developing usually fatal Bronchopneumonia, often seen w/ aspiration of vomitus