Pulmonary Important Points Flashcards
Atelectasis
- alveolar collapse
- happens when surface tension inc. possibly due to lack of surfactant
Cartilage and goblet cells extend to the end of the _______.
Bronchi.
Cilia terminate in the _________.
Respiratory Bronchioles.
Club (Clara Cells)
- non-ciliated
- secretory granules that secrete a component of surfactant
- degrade toxins
- act as reserve cells
- present in bronchioles
Lecithin-sphingomyelin ratio of ______ in amniotic fluid indicates fetal lung maturity.
> 2.0
Aspirated objects will most likely go to the:
-lower lobe of the right lung
Consequence of Pulmonary Hypertension
- cor pulmonale
- and subsequent right ventricular failure
Cor Pulmonale
- alteration in the structure and function of the right ventricle caused by a primary disorder of the respiratory system
- chronic hypoxic pulmonary vasoconstriction can lead to cor pulmonale
5 Causes of Hypoxemia
- normal A-a gradient:
- -high altitude
- -hypoventilation
- inc. A-a gradient:
- -V/Q mismatch
- -diffusion limitation
- -R to L shunt
Epistaxis
-nose bleed
Obstructive Lung Diseases
- chronic bronchitis
- emphysema
- asthma
- bronchiectasis
- FEV1/FVC ratio dec. (hallmark)
Chronic Bronchitis
- blue bloater
- hyperplasia of mucous secreting glands in bronchi
- productive cough >3 months per year
- findings: wheezing, crackles, cyanosis, dyspnea, hypercapnia
Emphysema
- pink puffer
- enlargement of airspaces, dec. recoil
- dec. diffusing capacity for CO resulting from destruction of alveolar walls
- inc. in lung compliance
- two types: centriacinar (smoking related) and panacinar (a1-antitrypsin deficiency)
- exhalation through pursed lips, barrel chested
- dyspnea and cough with MINIMAL sputum
- weight loss common due to inc. work of breathing
- DLCO will be decreased
Asthma
- bronchial hyperresponsiveness causes reversible bronchoconstriction
- smooth muscle hypertrophy
- can be triggered by viruses, allergens, stress
- test with methacholine challenge
- findings: cough, wheezing, tachypnea, dyspnea, hypoxemia, inc. inspiratory/expiratory ratio, pulsus paradozis, mucus plugging
Bronchiectasis
- chronic necrotizing infection of bronchi
- premanently dilated airways
- purulent (pus), foul smelling sputum
- recurrent infections
- associated with bronchial obstruction, poor ciliary motility, cystic fibrosis, allergic bronchopulmonary aspergillosis
Restrictive Diseases
- FEV1/FVC ratio > 80%
- types
- -poor breathing mechanics: polio, myasthenia gravis, scoliosis, morbid obesity
- -interstitial lung disease (inc. A-a gradient): ARDS, neonatal respiratory distress syndrome, pneumoconioses, sarcoidosis, idiopathic pulmonary fibrosis, goodpasture, langerhans cell histiocytosis, hypersensitivity pneumonitis, drug toxicity
Hypersensitivity Pneumonitis
- mixed type III/IV hypersensitivity reaction to environmental antigen
- eosinophilic granulomatous reaction
- dyspnea, cough, chest tightness, headache, fever hours after exposure
- often seen in farmers and those exposed to birds
- chronic exposure leads to interstitial fibrosis
-pneumoconioses
- interstitial fibrosis due to CHRONIC occupational exposure
- coal workers lung
- silicosis
- asbestosis
- inc. risk cor pulmonale and Caplan syndrome (RA and pneumoconioses with intrapulmonary nodules)
Acute Respiratory Distress Syndrome (ARDS)
- characterized by acute onset respiratory failure, bilateral lung opacities, no HF
- may be caused by trauma, sepsis, shock , gastric aspiration, uremia, acute pancreatitis, amniotic fluid embolism
- diffuse alveolar damage leads to inc. alveolar capillary permenability, leads to protein-rich leakage into alveoli and noncardiogenic pulmonary edema
- results in formation of intra-alveolar hyaline membranes (pink rivers)
- management: mechanical ventilation with low tidal volume, address underlying cause
Obesity Hypoventilation Syndrome
-obesity leads to hypoventilation, leads to dec. PaO2 and inc. PaCO2 during sleep, leads to inc. PaCO2 during waking hours (retention)
Pulmonary Hypertension
- hypertension > 25 at rest
- results in arteriosclerosis, medial hypertrophy, intimal fibrosis of pulmonary arteries
- results in plexiform lesions on histology
- 5 types:
- -pulmonary arterial hypertension
- -PH due to L heart disease
- -PH due to lung diseases or hypoxia
- -chronic thromboembolic PHH
- -multifactorial PH
Pleural Effusion Physical Findings
- dec. breath sounds
- dull on percussion
Atelectasis (bronchial obstruction) Physical Findings
- dec. breath sounds
- dull on percussion
Simple Pneumothorax Physical Findings
- dec. breath sounds
- hyperresonant on percussion
Tension Pneumothorax Physical Findings
- dec. breath sounds
- hyperresonant on percussion
Consolidation (lobar pneumonia, pulmonary edema) Physical Findings
- bronchial breath sounds; late inspiratory crackles
- dull on percussion
Types of Pneumonia
- lobar: intra-alveolar exudate leads to consolidation and may involve lobe or entire lung
- bronchopneumonia: acute inflammatory infiltrates from bronchioles into adjacent alveoli; patchy distribution involving > 1 lobe
- interstitial (atypical): diffuse patchy inflammation localized to interstitial areas at alveolar walls; diffuse distribution involving > 1 lobe, generally follows more indolent course (walking pneumonia)
Mesothelioma
- malignancy of the pleura associated with asbestos
- may result in emorrhagic pleural effusion (exudative), pleural thickening
- smoking not risk factor
Small Cell Carcinoma
- central location
- very aggressive
- neoplasm of neuroendocrine Kulchitsky cells (small, dark blue cells)
- nucleus forming
Adenocarcinoma
- peripheral location
- non-small cell
- most common lung cancer in non-smokers
- associated with clubbing
- apparent “thickening” of alveolar septa (grows along alveolar septa)
- may form gland-like structures
Squamous Cell Carcinoma
- central location
- non-small cell
- hilar mass arising from bronchus
- cavitation
- cigarettes are cause
- hypercalcemia
- keratin pearls and intercellular bridges
Large Cell Carcinoma
- highly anaplastic
- poor prognosis
- less responsive to chemo
- pleomorphic giant cells
- can secrete b-HCG
Antihistamines
- primary use in allergic rhinitis, minor role in viral cold symptoms
- reversible inhibitors of H1 histamine receptors
1st gen: diphenhydramine, dimenhydrinate, chlorpheniramine
- -clinical uses: allergy, motion sickness, sleep aid
- -toxicity: sedation, antimuscarinic, anti-a-adrenergic
2nd gen: loratadine, fexofenadine, desloratadine, cetirizine
- -clinical uses: allergy
- -toxicity: far less sedating than 1st gen because of dec. entry into CNS
Decongestants
- vasoconstrictors
- primary use in allergic rhinitis and viral cold infections
- pseudoephedrine (oral)
- phenylephrine (oral or topical)
- mechanism: a-adrenergic agonists, used as nasal decongestants
- clinical use: reduce hyperemia, edema, nasal congestion,; open obstructed eustachian tubes
- pseudoephedrine also used to illegally make meth
- toxocity: hypertension; can cause CNS stimulation/anxiety
Antitussives
- some use in coughs associated with viral cold symptoms, allergic rhinitis, asthma, COPD
- dextromethorphan (synthetic codeine analog); most commonly used OTC cough-suppressent
- has mild opioid effect when used in excess
- naloxone can be given for overdose
- mild abuse potential
- may cause serotonin syndrome if combined with other serotonergic agents
- robo-tripping possible
Expectorants
- some utility in viral cold infections, COPD
- guaifenesin: things respiratory secretions; does not suppress cough reflex
- N-acetylcysteine: mucolytic- can loosen mucous plugs in CF pts by disrupting disulfide bonds; also used as an antidote for acetaminophen overdose
Mucolytics
-some utility in viral cold infections, COPD
B2-Agonists
Asthma
- albuterol: relaxes bronchial smooth muscle; used during acute exacerbation
- salmeterol, formoterol: long acting agents for prophylaxis; adverse effects are tremor and arrhythmia
Pulmonary Hypertension Drugs
- endothelin receptor antagonsits: includ bosentan; competitively antagonize endotheln-1 receptors, leading to dec. pulmonary vascular resistance; hepatotoxic
- PDE-5 inhibitors: include sildenafil; inhibit cGMP PDE5 and prolong vasodilatory effect of nitric oxide, also used to tx erectile dysfunction
- prostacyclin analogs: include epoprostenol, iloporst; prostocyclines with direct vsodilatory effects on pulmonary and systemic arterial vascular beds; inhibit platelet aggregation; side effects: flushing, jaw pain
Corticosteroids
- fluticasone, budesonide: inhibit synthesis of virtually all cytokines; inactivate NFkB
- first line therapy for chronic asthma
Muscarinic Antagonists
- ipratropium
- competitively blocks muscarinic receptors, preventing bronchoconstriction
- also used for COPD
- tiotropium is long acting
Antileukotrienes
- montelukast, zafirlukast: block leukotriene receptors; esp. good for aspirin-induced asthma
- zileuton: 5-lipoxygenase pathway inhibitor; blocks conversion of arachidonic acid to leukotrienes; hepatotoxic
Omalizumab
- monoclonal anti-IgE antibody
- binds mostly unbound serum IgE and blocks binding
- used in allergic asthma resistant to inhaled steroids and long-acting B2-agonists
Methylixanthines
- theophylline: likely causes bronchodilation by inhibiting phosphodiesterase, leading to inc. in cAMP levels due to dec. cAMP hydrolysis
- usage is limited because of narrow therapeutic index; metabolized by cytochrome P-450
- blocks actions of adenosine
Idiopathic Pulmonary Fibrosis
- progressive dyspnea and cough
- fibrosis on lung CT
- tx is lung transplantation
- may see honeycombing
Sarcoidosis
- systemic disease characterized by non-caseating (non-necrotic) granulomas in multiple organs
- classically seen in African American females
- etiology is unknown; likely due to CD4+ helper T cell response to unknown antigen
- restrictive lung disease
- cough, SOB
- tx: steroids, may resolve spontaneously