Pathophysiology Chapter 23

Restrictive Lung Disease

stiff lungs, stiff chest wall, respiratory muscle weakness, might here crackle of stiff alveoli popping

Restrictive Lung Disease results from

decreased lung expansion due to alterations in lung parenchyma, pleura, chest wall, neuromuscular function

lung with restrictive lung disease would

not be as spongy as a normal lung

lung parenchyma disoders

fibrotic interstial lung diseases, atelactatic disoders

fibrotic interstital lung diseases

characterized by infliltration of alevoloar walls by cells, fluid and connective tissue, incidence is 5:100,000

fibrotic intersitital lung disease can be

acute, subacute, or chronic but if left untreated can progress to irreversible fibrosis

diffuse interstial lung disease immune reaction

injury to alveolar epilialial or capillary endothelial cells, intersitial and alevolar wall thicken, increased collagen bundles in interstitium

diffuse intersitial lung disease inflammation

occurs early, reversible, triggering event leads to inflammatory response, increased membrane permeability and movement of fluid/debris into alveoli

diffuse interstitial lung diease fibrosis

fibroblastic proliferation and deposition of large amount of collage, caused by increased mesenchumal cells and firboblasts in intersititum, alvelor walls thicken with fibrous tissue

diffuse interstitial lung disease destruction

end stage of disease, loss of alveolar walls

diffuse interstitial lung disease clinical manifestations

progressive dyspena, rapid shallow breathing, non productive cough, clubbing of nail beds, bibasialr expiratory crackles, cyanosis late finding, weight loss, inability to increased cardiac output with exercise

diffuser interstitial lung disease diagnosis

chest x ray, open lung biopsy, transbronchial biopsy, bronchoalveolar lavage

diffuse interstitial lung disease treatment

stop smoking, avoid enviornmental exposures, anti inflammatory agents, immunosupressive agents, lung transplant

sarcoidosis eitology

acute or chronic, unkown cause, immunologic

sarcoidosis

charactereized by noncaseating granulomas, activation of alveolar machrophage to unkown tirgger, mainly in lungs but can be aywhere

sarcoidosis acute form

common in women in 20-30s

sarcoidosis chronic form

common in 30s-40s

sarcoidosis pathogenesis

development of multiple unifform non caseating eptheloid granulomas, fibrotic and surrounded by large histiocytes, abnormal t cell function, asteroid bodus within granulomas

sarcoidosis clinical manifestations

fatigue, weight loss, fever, dyspnea, dry cough, subcutaneous nodules, hyperpigmentation, heptosplenomegaly, lymphadenopathy

sarcoidosis diagnosis

bronchoalveolar lavage to monitor cell content would increase lymphocytes and high CD4/8 cell ratio, transbronical lung biopsy finds noncaseating granuloms, chest xray for staging

sarcoidosis treatment

corticosteroids, immunosupressive agents

Atalectasis

incompelte expansion/collapse, not a disease but seen in many disease states

acute respiratroy distress sydrome

diffuse alveolar damage, damge to alveolar capillary membrane, mortalilty 30-60%, around 150,000 cases a year, adults

acute respiratroy distress sydrome causes

severe trauma, sepsis 40%, aspiration of gastric acid 30%, shock

acute respiratroy distress sydrome pathogenesis

widespread pulmonary inflammation leading to noncardiogenic pulomary edema, leaky pulomary capillaries, etelactsis lack of surgactant, fibrosis

Fibrosis

inflammatory deposition of proteins

acute respiratory distress sysdrome steps

injury to alveloi

changes in diamater of alveoli

injury to pulmonary circulation

disruptions in O2 transport and utilization

acute respiratroy distress syndrom common findings

severe hypoexmia- intrapulmonary blood shunting

decrease in lung compliance- loss of surgactant, increased recoil pressure, impaired ventilation

diffuse alveolar infiltrates

noncardiogenic pulmonary edema

acute respiratroy distress syndrom early manifestations

suddent respiratory distress, slight pulse increase, dyspnea, low PaO2, shallow rapid breahting

acute respiratroy distress syndrom late manifestations

tachycardia, tachypnea, hypotension, rstlesness, crackles rhonchim use of acessory msucles, cyanosis

acute respiratory distress syndrome diagnosis

hypoexmia refractroy to increased levels of supplemental O2, hypoxia, acidosis, hypercapnia, diffuse whiteout chest xray, atelactsis, cellular debris, inerstitial and alveolar edema

acute respiratory distress syndrome treatment

enhance tissue oxygenation until inflmmation resolves, adress underlying cause, maintain fluid electrolye balance, block system inflammatory cells

poliolyelitits

viral disease where poliovirus attacks motor nerve cells of spinal cord and brainstem, 8 cases a uear due to unvax, 95% infections asymptomatic

poliomyelitits symtpoms

fever, headace, vomit, diarrhea, constipation, sore throat, chronic respiratory insufficiency

amyotrophic lateral sclerosis

degenerative disease of nervous system(upper and lower moter neurons), progressive muscle weakness until respiratory muscles stop working leading to death

amyotrophic lateral sclerosis prevelance

males to females 1:2, 5:100,000

musclar dystrophie, duschenne

progressive muscular weakness, initally in lower extremeilies, repsiratory msucles become involved in 20-30s, leading to hypoxia, hypercapnia, frequent respiratory infections

musclar dystrophie, duschenne etiology

hereditary, x linked recessive, 1/3500 births

guillain barre syndrome/ acute polyneuritis eitology

mortality 3%, demylenation of peripheral nerves, history of recent viral or bacteral illnes 66% if cases follwoed by ascending paralysis, often invovling campylobacter

guillain barre syndrome/ acute polyneuritis clinical manifestations

weakness and paralyisis begin in lower extremeties and ascend upward, severe cases respiratroy msucle weakness accompanies limb and trunk symptoms

mysathenia gravis etiology

2-5 cases a year, abnormality at NMJ, decreased number of receptors on msucle, weakness and fatgiue of voluntary muscles innverated by cranial nerves, peripheral and respiratory muscles can be affected

myasthenia gravis clinical manifestation

symptoms managed by appropriate therapy, respiratroy failure can be due to increasing deverity of illness, individual episodes of respiratory failure are potentiall reversible

pneumonia

inflammatory reaction in alveoli and interstirum caused by an infectious agent, lower respiratroy infection

pneumonia causes

aspiratroy of orophargeal secreation composed of normal bacterial flora or gastric contents(35%)

virus

contamination from systemic circulation

any organism can cause

pnemonia classifications

community acquired(atypical), hosptial acquired, bacterial, viral, fungal

viral pnemonias

frequently interstitial not alveolar, does not produce exudative fluids

bacterial pnemonias

generally alveolar

pneymonia pathogenesis

normal pulmonary defense mechanism comprimised, organism enters lungs and triggers inflammation, inflammaorty cells invade alveoalr septa, air spaces fill with exudative fluid

pneumonia clinical manifestations

crackles and broncial brath sounds, chills, feber, cough, purulent sputum

pneumonia diagnosis

chest x ray- white shadows

sputum- culture and sensitivity from deep in lungs

WBC> 15,000 acute bacterial

pneumonia treatment

antibiotic therapy based on sensitivity of culture