Pathophysiology(lungs)*

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COPD disorder morphologically manifested by bronchial smooth muscle hypertrophy,hyperplasia of goblet cells,thickening & hyalinization of basement membranes,proliferation of eosinophils & intrabronchial mucous plugs: Bronchial asthma
-Curshmann Spirals(whorl-like form. of epithelial cells);Charcot-Leyden Crystals(crystalloids of eosinophil-derived proteins)
COPD disorder presenting w/ productive cough lasting at least 3 consecutive months over at least 2 consecutive years charact. by hypersecretion of mucus due to hyperplasia of mucus-secreting submucosal glands: Chronic Bronchitis
-assoc. w/ cigarette smoking,air pollution,infxn.,& genetic factors
Chills, fever, malaise, pleuritic pain, & rusty sputum: Pneumonia
->90% of lobar pneumonia is caused by Strep. pneumoniae; bronchopneumonia shows patchy consolidation
Dilatation of air spaces w/ s destruction of alveolar walls: Emphysema
-results from accelerated protease & elastase destruction of the lung
Harmless black pigment in the lungs: Anthracosis
-common in coalminers, urban dwellers, or smokers
Most common malignant tumor of the larynyx seen often in men >40yrs who cigarette smoke & drink alcohol: Squamous Cell Carcinoma
-symptoms of persistent hoarseness
Persistent productive cough for at least 3 consecutive months in at least 2 consecutive years: Chronic Bronchitis
-incr. Reid index, w/c is a ratio of the thickness of the mucosal gland to the thickness of bronchiolar wall
Copious purulent sputum, hemoptysis, & recurrent lung infections w/c may lead to abscess: Bronchiectasis
-bronchi & bronchioles can be dilated up to 4 times normal size
Lung tumors w/ strongest correlation to smoking: Small cell carcinoma & Squamous cell carcinoma of the lung
-both types localize near the hilus(centrally)
Most prevalent chronic occupational disease in the world: Silicosis
Noncaseating granulomas in the lungs often in a young, adult, African American female: Sarcoidosis
-may be detected incidentally as bilateral hilar adenopathy
Embolism obstructing the bifurcation of the pulmonary artery: Saddle embolus
Cause of sudden death often in immobalized postoperative patients: Pulmonary Embolism
-thrombi are most often from the deep veins of the lower ext.
Pulmonary vascular dse. caused by inc. hydrostatic presssure(left vent. failure,inc. alveolar capillary permeability(infl. alveolar rxn due to inhalation of toxic subst.), & by rapid ascent to high altitude: Pulmonary Edema
-intra-alveolar accumulation of fluid
Alpha-1-antitrypsin deficiency: Panacinar emphysema
-alpha-1-antitrypsin inhibits proteases, particularly elastase
Assoc. w/ asbestos exposure: Malignant Mesothelioma
-neoplasm of visceral or parietal pleura or peritoneal neoplasm
Severe dyspnea, wheezing, hyperactive airways, & bronchospasm triggered by various stimuli: Bronchial asthma
-most commonly IgE mediated, Type I hypersensitivty rxn. in the lung
Pulmonary vascular dse. cuased by COPD,inc. pulmonary bld. flow(cong. L-R shunt),inc.resistance w/in the pulmonary circl.(embolus or vasoconstriction due to hypoxia),inc. bld. viscosity(polycythemia): Secondary pulmonary hypertension
-more common than Primary(unknown etiology,poor prognosis)
Restrictive Pulmonary Dse: Adult Resp. Distress Synd.(diffuse alveolar damage), pneumoconiosis, silicosis, sarcoidosis
-reduced total lung capacity bec. of dec. expansion of lung parenchyma
Rapid onset of resp. insufficiency refractory to oxygen therapy assoc. w/ sepsis, infxn., aspiration, or trauma: Adult resp. distress syndrome(diffuse alveolar damage)
-histologically characterized by intra-alveolar hyaline membranes
Most common bronchogenic carcinoma type in women & nonsmokers: Adenocarcinoma of the lung
-localize peripherally
Fever, night sweats, weight loss, & hemoptysis: Tuberculosis(TB)
-Ghon complex in primary TB, cavitary lesions in the lung apices in secondary TB
Tumor assoc. w/ hypercalcimia due to elaboration of parathyroid hormone-related peptide: Squamous cell carcinoma of the lung
Rupture of apical subpleural blebs in young px.: Spontaneous idiopathic Pneumothorax
Blue bloater: Chronic Bronchitis
-Cyanosis resulting from severe hypoxia
Heart Failure Cells: Chronic passive congestion of the lung
-Hemosiderin-laden macrophages
Neoplastic columnar & cuboidal epithelial cells that line the alveolar septa: Bronchioloalveolar Carcinoma
-tumor cells are also found loose in alveolar spaces
Assoc. w/ SIADH & Cushing syndrome as paraneoplastic syndromes: Small Cell Carcinoma
-has the worst prognosis of bronchogenic carcinoma subtypes
Chronic Obstructive Pulmonary diseases (COPD): Emphysema, chronic bronchitis, bronchieactasis, & bronchial asthma
-caused by airway narrowing or loss of elastic recoil of the lung, resulting in decreased forced expiratory volume at 1sec.
Pink Puffer: Emphysema
-px. who overventilates & remains well-oxygenated
Central region of caseating necrosis encicled by lymphocytes, plasma cellms, & epitheloid cells: Granulomatous Inflamation
-found in TB, fungal infxn., foreign body, & sarcoidosis
2 types of bronchial asthma: 1)Extrinsic(immune)asthma:type I hypersensitivity response involving
Ige bound to mast cells;childhood; family hx. of allergies
2)Intrinsic(nonimmune)asthma:assoc. w/ chronic bronchitis,exercise
or cold induced asthma & other asthma variants;adult life;no family
hx. of allergies
A group of resp. disorders charact. by airflow obstruction,dec. FEV1/FVC ratio: Chronic Obstructive Pulmonary Dse.(COPD)
-Bronchial asthma,chronic bronchitis, pulmonary
emphysema,bronchiectasis
Benign neoplasm of the larynx located in the true vocal cords w/c could be caused by HPV in children: Laryngeal papilloma
-occur singly & may under go malignant change in adults
Malignant tumors of the nose & nasal sinuses: Nasopharyngeal carcinoma(EBV),Squamous Cell Carcinoma(most common nasal tumor),Adenocarcinoma(5% of malignant tumors),Plasmacytoma(plasma cell neoplasm)
Most common upper resp. tract disorder caused by viruses manifested by coryza,sneezing,nasal congestion, & mild sore throat: Common Cold
-Adenovirus is most common virus
Tumor of the larynx located in the true vocal cords presenting as a benign laryngeal polyp induced by chronic irritation(excessive use of voice,heavy cigarette smoking): Singer's nodule
Upper resp. tract illness mediated by IgE type I immune reaction involving mucosal & submucosal mast cells characterized by inc. eosinophils in peripheral bld. & nasal discharge: Allergic Rhinitis
A localized area of suppuration in the parenchyma due to bronchial obstruction(often by cancer),aspiration of gastric contents,complication of bact. pneumonia & is seen in px. who aspirate during loss of consciouseness(drug overdose,neurologic disord: Lung Abscess
-manifest as fever,foul smelling purulent sputum, & x-ray evidence of fluid filled cavity
An acute viral infxn. charact. by inflammation of the larynx, trachea, & epiglottis that is life-threatening in infants: Acute laryngotracheobronchitis(croup)
-symptoms of harsh cough & inspiratory stridor
COPD characterized by copious foul smelling purulent sputum,hemoptysis, recurrent pulmonary infxn. w/c may lead to lung abscess: Bronchiectasis
-assoc. w/ bronchial obstruction, cystic fibrosis,intralobar sequestration of the lung,necrotizing pneumonia
4 types of emphysema: Centrilobar(dilation of resp. bronchioles,localized to upper lobes,Coal Worker's Pneumoconiosis); Panacinar(dilatation of entire acinus, alveoli,alveolar ducts,resp. bronchioles,terminal bronchioles); Paraseptal(dilatation of distal part of acinus,localized to pleura & interlobar septa,assoc. w/ subpleural bullae or blebs); Irregular(most common,asymptomatic,irregular involvement of the acinus w/ scarring w/in the walls)
Type of emphysema assoc. w/ loss of elasticity due to alpha1-antitrypsin def.(alpha1-protease inhib.): Panacinar Emphysema
-affects lower zones;most severe at the base
Causes of Emphysema: Effect of elastase(neutralized by alpha1-antitrypsin) w/c induces destruction of elastin on the alveolar wall;Cigarette smoking(attracts neutrophil & macrophages,sources of elastase);Hereditary Alpha1-antitrypsin def.(piZ allele,homozygous state-piZZ)
COPD characterized by permanent abnormal bronchial dilation often in the lower lobes of both lungs due to chronic infxn.,inflammation & necrosis of the bronchial wall: Bronchiectasis
-predisposed by bronchial obstruction(tumor) & chronic sinusitis w/ postnasal drip
Synd. manifested by bronchiectasis, sinusitis,situs inversus,hearing loss,male sterility, caused by defective motility in celia located in the resp.,auditory,& sperm: Kartegener Synd.
Restrictive pulmonary dse. produced by diffuse alveolar damage(alveolar capillary permeab.~leakage of protein-rich fluid into the alveoli) & form. of intra-alveolar hyaline memb. resulting in severe imparement of resp. gas exchange: Adult resp. distress synd.(ARDS)
Most common cause of resp. failure in newborn & death in premature infants due to surfactant(dipalmitoyl lecithin;secreted by type II pneunocytes)def. presenting w/ dyspnea,cyanosis,tachypnea at birth: Neonatal resp.distress synd.(hyaline membrane dse)
-predisposed by prematurity,maternal diabetes mellitus,birth by cesarean section
Complications & assoc. conditions in neonatal resp. distress synd: Bronchopulmonary dysplasia(due to tx. w/ high conc. of O2 & mech. vent.); Patent ductus arteriosus(failure of closure of the ductus due to immaturity & hypoxia);Intraventricular brain hemorrgh.;Necrotizing enterocolitis(fulminant infl. of small & large intest.)
Environmental disease caused by inhalation of inorganic dust particles exemplified in Anthracosis,Coal worker's pneumoconiosis,Silicosis, & Asbestosis: Pneumoconioses
Vol. of insp. or exp. air w/ normal breath;vol. insp. above the tidal vol.; vol. exp. after expiration of tidal vol.;vol. in the lungs after max. expiration: Tidal Vol.;Inspiratory reserve vol.; Expiratory reserve vol.;Residual vol.(cannot be measured by spirometry)
Defined as the vol. in the lungs that does not participate in gas exchange; functional measurement;greater than anatomical dead space in lung dse.: Physiologic Dead Space=Tidal vol.[(PCO2 of art. bld.mmHg-PCO2 of expired air mmHg)/PCO2 of art bld.]
Equation for alveolar vent.: Alveolar vent=(Tidal vol-Dead space)breaths/min
Sum of Tidal vol+IRV;sum of ERV+ residual vol.;sum of tidal vol.,IRV,& ERV;vol. of air forcibly expired after max. inspiration;Sum of all four lung vol.: Inspiratory capcity;Functional residual Capacity(cannot be measured by spirometry);Vital Capacity;Total Lung Capacity(cannot be measured by spirometry)
A variant of Coal worker's pmeumoconiosis caused by inhalation of coal dust resulting in fibrotic nodules filled w/ necrotic black fluid w/c can result in bronchiectasis, pulmonary HPN,death due to resp. failure or right sided heart failure: Progressive massive fibrosis
-compared to "simple coal worker's pneumoconiosis" w/c produce no disability
An occupational lung dse. caused by inhilation of silica dust~ingestion by alveolar macrophage~damage to macrophage causes a infl. response; form. of silicot nodules w/c obstruct the airways & bld. vessels: Silicosis
-assoc w/ inc. susceptibilty to tuberculosis(silicotuberculosis)
An occupational lung dse due to uptake of asbestos by alveolar macrophage~ release of fibroblast stimulating growth factors~diffuse interstitial fibrosis(lower lobes) w/c predisposes to bronchogenic carcinoma & malignant mesothelioma: Asbestosis
-charact. by Ferruginous bodies(yellow-brown,rod-shape bodies w/ clubbed ends) & Hyalinized fibrocalcific plaques of the parietal pleura
Restrictive lung dse. of unknown etiology charact. by noncaseating granulomas involving multiple organ systems often presenting in early adult years in px. of African lineage: Sarcoidosis
-abn. findings of bilateral hilar lymphadenopathy,interstitial lung dse. presenting as diffuse reticular densities,hypercalcemia,hypercalciuria, hypergammaglobulinemia,inc. ACE activity
Common pathologic changes in sacoidosis: Interstitial lung dse.,enlarged hilar lymph nodes,ant. uveitis,erythema nodusom of the skin,polyarthritis
6 types of interstitial lung dse.: Hypersensitvity pneumonitis(extrinsic allergic alveolitis),Goodpasture synd.,Idiopathic pulmonary hemosiderosis,Eosinophilic granuloma, Idiopathic Pulmonary fibrosis, Sarcoidosis
Interstitial lung dse. due to proliferation of histiocytic cells w/c have cytoplasmic inclusions(Birbeck granules)resembling tennis rackets: Eosinophilic granuloma
-found in the lung or in bony sites(ribs)
Pulmonary vascular dse. found in >50% of all autopsies often resulting from DVT or assoc. w/ venous stasis,CHF, prolonged bed rest or sitting & may result in hemorrhagic(red)infarcts: Pulmonary embolism
Pulmonary infxn. charact. by fever & chills,productive cough,blood-tinged or rusty sputum,pleuritic pain,hypoxia w/ shortness of breath all due to an infl. process of infectious origin affecting the pulmonary parenchyma: Pneumonia
-occurs in 3 morphologic & clinical patterns(lobar,broncho,interstitial)
Type of pneumonia often caused by Streptococcus pneumoniae(pneumococus) w/c involves the entire lobe & charact. by intra-alveolar exudate: Lobar Pneumonia
-if not tx.,morphologically evolve in 4 stages(congestion,red hepatization, gray hepatization,resolution)
Type of pneumonia caused by many organisms charact. by patchy infl. involving one or more lobes w/ infl. infiltrates extending from the bronhioles to adjacent alveoli: Bronchopneumonia
Type of pneumonia commonly caused by Mycoplasma pneumonia or viruses charact. by diffuse,patchy infl. localized to interstitial areas of alveolar walls: Interstitial(primary atypical)pneumonia
-Mycoplasma pneumonia is most common form
Most common form of interstitial pneumonia w/c may occur in epidemics in children-young adults w/ an insidous onset & self-limited course charact. by infl. in the interstitium w/ no exudate in alveolar space, & intra-alveolar hyaline memb.: Mycoplasma Pneumonia
-diagnosed by sputum cultures & assoc. w/ nonspecific cold agglutinins(used to provide early diagnostic information)
Most common types of pneumonia in childhood caused most commonly by influenza virus,adenovirus,rhinovirus, RSV: Viral Pneumonia
-may also arise from rubeola(measles) producing Giant Cell Pneumonia & varicella(chickenpox)
Most common form of Ricketsial pneumonia caused by Coxiella bunettii in people who work near cattle or sheep,inhale the organism,or drink unpasteurized milk: Q fever
Most common opportunistic infxn. in AIDS px. caused by P.carinii: Pneumocystis carinii pneumonia
-diagnosed by biopsy or bronchial washing specimens
Pulmonary infxn. occuring world wide charact. by Ghon complex(subpleural parenchymal lesion w/ involve hilar lymph nodes),central caseous necrosis often by Langhan giant cells w/c could be seen on x-ray: Primary Tuberculosis
-asymptomatic;does not progress to clinically evident dse.
Type of tuberculosis w/c results from activation of the Gohn complex resulting in localixed lesions on the apical lobes & hilar lymph nodes, tubercle form.,cavitary lesions, scarring,calcification & metastasis(miliary tuberculosis,extrapulmonary: Secondary Tuberculois
-cavitary lesion is charact.; extrapulmonary tuberculosis include tuberculous meningitis,Pott dse. of the spine,paravertebral abscess, or psoas abscess
Immune mech. in pathogenesis of tuberculosis: Ingestion of tubercle bacilli by macrophage(presentation of antigens to CD4 Th1 Tcells in context of class II MHC mol.)~proliferation of CD4+ Tcells & secretion of cytokines;some macrophage are transformed to epithelioid cells & Langhans multinucleated giant cells;caseous necrosis due to action of cytokines secondary to immunologically stimulated cells
Progressive diability,fever, hemoptysis,pleural effusion(often bloody & generalized wasting are all clinical charact. of this pulmonary infxn.: Secondary Tuberculosis
A delayed hypersensitivity response w/c is positive in primary & secondary tuberculosis,represents hypersensitivity & relative immunity, & remains positive throughout life: Positive Tuberculin skin result
Occurs in primary & disseminated forms; fungal spherules containing endospores found w/in granulomas: Coccidioidomycosis
-caused by Coccidioides immitis
Pulmonary infxn. similar to tuberculosis;occurs in primary & secondary forms;results in multiple pulmonary lesions w/ late calcification;dissiminated form marked by multisystem involvement w/ infiltrates of macrophages filled w/ fungal yeast forms: Histoplasmosis
-caused by Histoplasma capsulatum
Typical pulmonary opportunistic infxn.; may disseminate to the brain; caused by a gram post. aerobic, filamentous,weakly acid-fast bacteria closely related to Actinomyces: Nocardiosis
-caused by Nocardia
Pulmonary infxn. w/c begun in the lungs w/c may produce meningitis; etiological agent is charact. by encapsulated appearance visualized in India ink: Cryptococcosis
-Cryptococcocus neoformans
Pulmonary infxn. charact. by a predilection for growth into vessels, w/ consequent widespread hematogenouse dissemination: Aspergillosis
-caused by Aspergillus
Pulmonary infxn. in immunocompromised px.;invasive form produces blood borne dissemination;pulmonary,renal,hepatic abscesses & vegetative endocarditis: Candidiasis
-caused by Candida albicans
Pulmonary infxn. charact. by abscess & sinus tract form.;exudate containing charact. sulfur granules,yellow clumps of the organism: Actinomycosis
-caused by Actinomyces
Bronchogenic carcinoma located centrally appearing as a hilar mass often resulting in cavitation;assoc. w/ smoking;marked by inappropriate PTH-like activity w/ resultant hypercalcemia: Squamous cell carcinoma
Bronchogenic carcinoma located peripherally w/c develop on site of prior pulmonary infl. or injury(scar carcinoma);less clearly linked to smoking: Adenocarcinoma Bronchial-derived
Bronchogenic carcinoma located peripherally less clearly related to smoking;columnar-to-cuboidal tumor cells line alveolar walls;multiple densities on x-ray,mimicking pneumonia: Bronchioalveolar carcinoma
Most aggressive bronchogenic carcinoma least likely to by cured by surgery; usually already metastatic at diagnosis;assoc. w/ectopic production of ACTCH or ADH: Small Cell(oat cell)carcinoma
-undifferentiated tumor
Carcinoma of the lung located in major bronchi;have low malignancy, spreading by direct extension into adjacent tissues: Carcinoid carcinoma
-may result in carcinoid synd.
Leading cause of death from cancer in both men & women;directly proportional to the # of cigarrets smoked daily & # of years smoking;has 5 year survival rate of less than 10%;manifest as cough,hemoptasis,brochial obstruction, atelectasis & pn: Bronchogenic Carcinoma
-spreads by local extension to the pleura,pericardium, or ribs
Classification of Bronchogenic carcinoma: Subclassified into squamous cell carcinoma,adenocarcinoma(including bronchioalveolar carcinoma),small cell carcinoma, & large cell carcinoma;for therapeutic purposes,subclassified into small cell carcinoma(not surgically tx.) & non-small cell(can consider surgical tx)
Clinical features of Bronchogenic carcinoma: Superior Vena Cava synd.,Pancoast tumor w/ Horner synd.,hoarseness(recurrent laryngeal nerve paralysis), pleural effusion(bloody), Paraneoplastic endocrine synd.
Volume of air exp. in 1sec. after max inspiration after max. inspiration; normally 80% of the forced vital capacity(FEV1/FVC=.8): Forced expiratory vol(FEV1)
-in restrictive lung dse.(fibrosis), both FEV1 & FVC are reduced;in obstructive lung dse.(asthma),FEV1 is reduced more than FVC~FEV1/FVC is decreased
Causes of dec. lung compliance: High expanding pressures,inc. pulmonary venous pressure,fibrosis(deposition of collagen),lack of surfactant
Causes of increased lung compliance: Emphysema(dec. elastic fibers),age
Describes the distensibility of the lungs & chest wall;inversely related to elastance;slope of the pressure-vol. curve;change in vol. for a given change in transmural press.(alveolar press.-intrapleural press.): Compliance of the lung
Results from the attracive forces betw. molecules of liquid lining the alveoli;creates a collapsing pressure directly proportional to surface tension & inversely proportional to alveolar radius(Laplace's law): Surface Tension of the alveoli
-Collapsing press. on alveolus=[2(surface tension)/radius of the alveolus]
Reduces surface tension;inc. compliance;synthesized by type II alveolar cells;consist of dipalmitoyl phosphatidylcholine(DPPC);present in the fetus by 35th wk of gestation: Surfactant
-a lecithin:sphingomyelin ratio >2:1 in amniotic fluid reflects mature levels of surfactant
Driven by & directly proportional to the pressure difference betw. mouth & alveoli;inversely proportional to airway resistance~the higher the resistance,the lower the airflow: Air flow=Press. diff. betw. mouth & alveoli/airway resistance
Described by Poiseuille's law: Resistance to airways=[8(vicosity of insp. gas)length of airway]/[3.14(radius of the airway)to the 4th]
Major site of airway resistance: Medium size bronchi
Method w/c is used to measure intrapleural pressure: Ballon catheter in the esophagus
Description of pressure & flow at rest(before inspiratory begins): Alveolar press.=atmospheric press.(alveolar press. is 0);Intrapleural pressure is neg.;lung vol.is FRC
Description of pressure & airflow during inspiration: Contraction of inspiratory muscles~inc. thoracic vol.~dec. alveolar press less than atmosph. press.(pressure gradient);intrapleural press. bec.more neg.;lung vol. increases by 1 tidal vol.
Description of pressures & airflow in expiration: Alveolar press. > atmosph. press. due to elastic forces of the lung; Intrapleural press. returns to its resting value during a normal(passsive)expiration;during forced expiration, intrapleural press. bec. (+) w/c compresses the airways & makes exp. difficult;lung vol. return to FRC
Perfusion-limited exchange: Under normal conditions,N2O & O2 equilibrates early along the length of pulmonary capillary(equal of partial pressure betw. alveolar air & art. bld.)~diffusion of gas can be inc. if bld. flow is inc.
Diffusion-limited exchange: Occurs w/ CO2 & O2 during strenous exercise & in dse. states:Fibrosis(thickening of alveolar memb. w/c inc. diffusion distance restricts O2 diffuson);Emphysema(decrease surface area for diffusion);gas does not equilibrate by the time bld. reaches the end of the pulm. art.
Responsible for making adult hemoglobin less attractive to O2 as compared to fetal hemoglobin.: 2,3-diphosphoglycerate(DPG)
Max. amount of O2 that can be bound to hemoglobin;determined by hemoglobin conc. in bld.;limits the amount of O2 carried;measured at 100% saturaion: O2 Capacity
-compared to O2 Content w/c is total amount of O2 carried in bld(bound & dissolve O2).
Depends on the hemoglobin conc.,the PO2, & the P50 of hemoglobin: O2 Content=[O2-binding capacity(ml O2/100 ml bld.)(%sat.)]+ Dissolved O2(ml O2/100 ml bld.)
Shift to the right in the hemoglobin-O2 dissociation curve: Affinity of hemoglobin for O2 is dec., P50 is inc.;Inc. in PCO2 or dec. in pH(Bohr effect);inc. in temp.;inc. in 2,3-DPG conc.(adaptaion to chronic hypoxemia)
Shift to the left in the Hemoglobin-O2 dissociation curve: Affinity fo hemoglobin for O2 is inc.; P50 is dec.;dec. PCO2;inc. pH;dec. temp.;dec. 2,3-DPG conc.;dec. affinity of HbF for 2,3-DPG inc. O2 affinity; carbon monxide poisoning(hemoglobin %sat. stays at 50%)
3 forms in w/c CO2 is transported: Dissolved CO2(small amount), Carbaminohemoglobin(CO2 bound to hemoglobin,small amount),HCO3(major form,90%)
Transport of CO2 as HCO3 to the lungs: CO2 diffuses out of tissues into venous plasma & into RBC~in RBC(CO2+H20--H2CO3--H+HCO3);HCO3 leaves RBC(chloride shift)~HCO3 transp. to lungs & H+ is buffered by deoxyhemoglobin~in lungs, rxn. occur in reverse.
Distributtion of pulmonary bld. flow in zone 2: Art.press>alveolar press.>venous press.
-blood flow is medium;inc. of hydrostatic press. due to gravitational effects;bld. flow is driven by difference in pressure betw. alveolar & arterial
Right to left shunts: Normally occur(2% of CO bypasses the lungs);may be as high 50% of CO(Tetralogy of Fallot)~dec. art. PO2 due to admixture of venous bld. to art. bld.
Left to right shunts: More common than right to left shunt;caused by congenital anomalies(patent ductus arteriosus) or traumatic injury;doesn't result in dec. art. PO2
Effect of airway obstruction on V/Q ratio: Vent. is zero;V/Q ratio is zero(if perfusion is normal);no gas exchange; PCO2 & PO2 of pulmonary capillary bld. approaches their values in mixed venous bld.
Effects of bld. flow obstruction on V/Q ratio: V/Q ratio is infinite(if vent. is normal);no gass exchange;PO2 & PCO2 of alveolar gas approaches their values in inspired air
Distribution of pulmonary bld. flow in zone 3(base): Art.press>venous press.>alveolar press.
-blood flow is highest due to gravitational effects;bld. flow is driven betw. pressure of art. & venous;lowest V/Q~PO2 is lowest & PCO2 is highest bec. gas exchange is less efficient
Distribution of pulmonary bld flow due the effects of gravity in zone 1(apex): Alveolar press.>art.press>venous press.
-high alveolar press. compress the capillaries;dec. art. press. due to hemorrhage;inc. alveolar press. due to positve pressure ventilation;highest V/Q~PO2 is highest & PCO2 is lowest due to more efficient gas exchange
Function of the Dorsal resp. group of the Medullary resp. center located in the reticular form.: Inspiration
-Vagus nerve inputs inf. from peripheral chemoreceptors & mechanoreceptors in the lung; Glossopharyngeal nerve inputs inf. from peripheral chemoreceptors;Phrenic nerve relays output signals to diaphram
Center resp. for expiration: Ventral resp. group of the medullary resp. center in the reticular form.
-not active during normal ,quite breathing;active during exercise
Area of the brain w/c stimulates inspiration,producing a deep & prolonged inspiratory gasp(apneusis): Aneustic center
-located in lower pons
Area in the upper pons w/c inhibits inspiration~regulates inspiratory vol. & resp. rate: Pneumotaxic center
Area of the brain w/c can voluntarely control they're breathing(hyperventilate or hypoventilate): Cerebral Cortex
Chemoreceptors & meconreceptors w/c help control breathing: Central chemoreceptors of the medulla, peripheral chemoreceptors(carotid & aortic bodies),lung stretch receptors(Hering-Breuer reflex),irritant receptors,Juxtacapillary receptors(left heart failure),joint & muscle receptors(exercise)
Function of the central chemoreceptors in the medulla: Dec. in pH stimulates hyperventilation
-CO2(art. bld) diffuses into the CSF~ in CSF(CO2+H20--H2CO3--HCO3+H)~H+ acts directly on the central chemorecetor
Funct. of the carotid(located at the bifurcation of common caotid) & aortic bodies(located above & below the aortic arch) in control of breathing: Inc. breathing when PO2 levels are <60mmHg,inc. art. PCO2,inc. in art. H+(carotid body) or dec. pH
Respiratory response to exercise in regards to O2 consump.,CO2 prod.,vent. rate,art. PO2 & PCO2,art. pH,venous PCO2,pulmonary bld. flow,V/Q ratios: O2 consump.(inc.),CO2 prod.(inc.), vent. rate(inc. to match O2 consump. & CO2 prod.),art. PO2 & PCO2(no change)
,art. pH(no change in mod. exercise, dec. in strenous exercise),venous PCO2(inc.),pulm. bld. flow(inc.),V/Q ratio(evenly distributed in the lung)
Adaptation to high altitude in regards to alveolar PO2,art. PO2,vent. rate, art. pH,hemoglobin conc.,2,3-DPG conc., hemoglobin-O2 curve,pulmonary vascular resistance: Alveolar PO2(dec. due to dec. barometric press.),art.pH(hypoxemia), vent. rate(hypervent.),art. pH(respiratory alkalosis due to hyperventilation),hemoglobin conc.(polycythemia),2,3-DPG conc.(inc.), pulmonary vascular resistance(vasoconstriction due to hypoxemia~ hypertrophy of right vent.)

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Number of cards 129