Pulmonary System

upper respiratory tract

nasal cavity → oral cavity → pharynx → larynx → trachea

lower respiratory tract

tracheal carina → segmental bronchi → nonrespiratory bronchioles → respiratory bronchioles → alveolar ducts → alveolar sacs → alveoli

conducting airways of lower respiratory tract

trachea → segmental bronchi → nonrespiratory bronchioles

respiratory unit of lower respiratory tract

respiratory bronchioles → alveolar ducts → alveolar sacs → alveoli

ventilation (V)

gravity-independent movement of air in & out of lungs via a pressure gradient; affected by pathologies of airways, lungs, chest wall, or diaphragm

respiration

gas exchange of O₂ into bld and CO₂ out of bld; affected by pathologies of gas exchange tissues or CV system

s/s of hypoxemia

PaO₂ 80-100 mmHg: normal

PaO₂ 60-80 mmHg: tachycardic, dyspnea on exertion, respiratory distress

PaO₂ 50-60 mmHg: malaise, lightheadedness, nausea, vertigo, impaired judgment, uncoordination, restlessness

PaO₂ 35-60 mmHg: marked confusion, cardiac arrhythmias, labored respiration

PaO₂ 25-35 mmHg: cardiac arrest, decr renal bld flow, decr urine output, lactic acidosis, lethargy, loss of consciousness

PaO₂ <25 mmHg: decr minute ventilation due to depression of respiratory center

causes of hypoxemia

ventilation-perfusion mismatch, decr oxygen content, hypoventilation, alveolocapillary diffusion abnormaility, pulmonary shunting

common clinical causes of ventilation-perfusion mismatch

asthma, chronic bronchitis, pneumonia

common clinical causes of decr oxygen content

high altitude, low oxygen content, enclosed breathing space/suffocation

common clinical causes for hypoventilation

lack of neurological stim of respiratory center, oversedation, drug overdose, neurologic damage, COPD

common clinical causes of alveolocapillary diffusion abnormality

emphysema, fibrosis, edema

common clinical causes of pulmonary shunting

acute respiratory distress syndrome (ARDS), hyaline membrane disease (ARDS in newborns), atelectasis

tidal volume (TV)

amount inhald/exhaled during normal resting breath

inspiratory reserve volume (IRV)

amount inhaled beyond nromal resting breath (TV)

expiratory reserve volume (ERV)

amount exhaled beyond normal resting breath (TV)

residual volume (RV)

amount left in lungs after ERV has been exhaled; prevents complete collapse of lungs

inspiratory capacity (IC)

IC = IRV + TV; amount inhaled from REEP

vital capacity (VC)/forced expiratory vital capacity (FVC)

VC = IRV + TV + ERV; amount if air in lungs under volitional control

functional residual capacity (FRC)

FRC = ERV + RV; amount of air in lungs after normal resting exhalation

total lung capacity (TLC)

TLC = IRV + TV + ERV + RV; total amount within thorax during maximum inspiratory effort

forced expiratory volume in 1 second (FEV1)

amount of air exhaled during 1st second of FVC; norm = >70%

forced expiratory flow rate (FEF 25-75%)

slope of line drawn b/n 25% & 75% of exhaled volume on a FVC exhalation curve of smaller airways

perfusion (Q)

gravity-dependent flow of blood thru alveolar capillaries

___ /___ need to match for optimal respiration

V; Q

types of V/Q mismatches that can occur

dead space, shunt

anatomical dead space

gravity-independent ventilation but no perfusion in conducting airways; high V/Q ratio = more air than blood

physiological dead space

gravity-independent ventilation but no perfusion in pulmonary emboli; high V/Q ratio = more air than blood

shunt

gravity-dependent perfusion but no ventilation → complete atelectasis, pneumonia, pulmonary edema, alveolar collapse; low V/Q ratio = more blood than air

arterial oxygenation (PaO2)

measure of actual oxygen content in arterial blood via a blood gas test; norm = 80-100 mmHg

oxygen saturation (SpO2)

percent of hemoglobin (Hgb) binding sites in the blood that are carrying oxygen; can indicate hypoxemia

arterial blood gases (ABG) & norms

pH = 7.35-7.45

PaCO2 = 35-45 mmHg

PaO2 = 80-100 mmHg

HCO3 = 22-26 mEq/L

SpO2 = 95-100%

respiratory acidosis

pH < 7.35 & high PaCO2; HCO3 WNL; alveolar hypovent → early anxiety, restlessness, dyspnea, headache → late confusion, somnolence, coma

other causes: COPD, myasthenia

“I’m exhausted and can’t catch my breath”

respiratory alkalosis

pH > 7.45 & low PaCO2; HCO3 WNL; alveolar hypervent → dissiness, syncope, tingling, numbness

other causes: sepsis, liver disease, fever

“I’m anxious and lightheaded”

metabollic acidosis

pH < 7.35 & low HCO3; PaCO2 WNL; DKA/diarrhea/lactic or uremic acidosis → nausea, lethargy, coma, 2ndary hypervent (Kussmaul)

other causes: uncontrolled DM, ETOH, starvation, renal failure, acid intake, loss of alkaline body fluids

“I have a headache and I’m twitchy”

metabollic alkalosis

pH > 7.45 & high HCO3; PaCO2 WNL; vomiting/diurectics/steroids → dizziness, syncope, tingling, numbness, early tetany

“I’m dizzy and going to throw up”

pulmonary health condition classifications

acute vs. chronic; obstructive vs. restrictive; infectious; oncologic

pulmonary health conditions symptoms

cough, abnormal sputum/hemoptysis, dyspnea, substernal chets pain, cyanosis, digital clubbing, altered breathing patterns, hx of respiratory treatments

pulmonary health condition pain patterns

chest, ribs, UT, shoulder, T-spine that can radiate along medial arm; increases with inspiratory movements; can present w/ primary MS pain

pulmonary HTN can cause pain that is mistaken for ___ pain

cardiac

part of PT eval is differentiating cardiac pain from ___ pain, ___ pain, and ___ pain

pulmonary (wheezing); epigastric; breast

___ affects lung physiologic functions & its defense mechanisms

aging

structural changes that eventually lead to impaired gas exchange

repeated damage episodes, environmental exposure, cell death, decr chest wall compliance/incr stiffness, decr elastic recol, flattened alveoli, incr dead space w/ age

in the upper airway, decr ciliary movement w/ age can lead to difficulty clearing ___ & ___ → incr incidence of respiratory infections

mucus; debris

w/ age, respiratory muscle strength & endurance decr → …

dyspnea & eventually ventillatory pump failure

infectious pulmonary conditions

PNA, pneumocystitis carinii PNA, pulmonary TB; inability to get air into the lungs

pneumonia (PNA) & etiology

acute lung injury → inflammatory pulmonary response to infectious agents/toxins; bacterial/viral/fungal/mycoplasmal infection transmissible by air, circulation, sinus infection, aspiration; primary/2ndary conditions

pneumonia (PNA) pathogenesis

disruption of respiratory system biome; pathogen activates macrophages & cytokines to signal inflammatory cells → lungs flood w/ inflammatory cells & leak into pulmonary vasculature & alveoli → gas echange impaired

pneumonia (PNA) incidence/risk factors

viral hospital-acquired or ventilator; very common at >248/10,000; older age, smoking, poor nutrition, previous PNA, COPD, asthma, reduced function, poor oral hygiene, environmental exposures, immunsuppressive, oral steroid use, acid reducing meds, dysphagia

pneumonia (PNA) clinical manifestations

URI, pleuritic chest pain, productive cough (bacterial = rusty, viral = watery), dyspnea, tachypnea, crackles, fatigue, fever, chills, muscle aches → complicates into pleural effusion, empyema (pus pocket), rare lung abscess

pneumonia (PNA) Dx

community acquired based on symptoms, chest x-ray/CT, sputum culture, PCR & antigen testing; aspiration from blood culture, swallow study & sputum analysis

at height of pandemic, PTs were integral parts of ICU team providing…

proning, chest PT, enterventions to combat bedrest comorbidities

post-COVID, PTs have a large role in…

aerobic re-conditioning, reducing dyspnea, improving lung capacity, decr psychoemotional alterations, and incr muscle strength

pneumocystitis carinii PNA & etiology/pathogenesis

fungal PNA that affects immunocompromised ppl & spreads via aerosolized particles; possible reactivation of an infection in early childhood; can spread out of the lungs; leading cause of death for ppl w/ AIDS (w/ HIV = slow progress, w/o HIV = rapid progress)

pneumocystitis carinii PNA incidence/risk factors

low CD4 count/T-cell count, graft-vs-host disease, immunnosuppression, low serum albumin, coinfection w/ bacteria/cytomegalovirus/aspirgillious

pneumocytosis carinii PNA clinical manifestations

fever, impaired gas exchange, altered respiratory function, non-productive cough, fatigue, tachypnea, weight loss

pneumocytosis carinii PNA DDx

PCP care for pts w/ immune dysfunction, similar to PNA diagnostics (chest x-ray/CT, sputum culture, PCR, antigen testing, blood culture, swallow study)

pulmonary TB & etiology/pathogenesis

infectious, inflammatory systemic disease that can spread from lungs to other organs & can survive for months in just sputum; exposure by close proximity and long duration; active/latent

mycobacterium TB causes…

granulomas, caseous necrosis, cavity formation

pulmonary TB incidence/risk factors

global health problem (1.3M deaths/year but declining in US), multi-drug resistant TB from stopping taking meds too soon, immunocompromised & chronically ill, close contact in poor ventilation

pulmonary TB clinical manifestations

productive cough x3+ weeks, unexplained weight loss, night sweats, fever, fatigue, chest pain, adventitious breath sounds

pulmonary TB Dx

H&P, chest x-ray, tuberculin skin test, assays, bld tests, sputum analysis, foreign-born but vaccinated ppl

latent pulmonary TB treatment

to prevent active TB; meds for 3-9 months: isoniazid (INH), rifapentine (RPT), rifampin (RIF)

active pulmonary TB treatment

identify & isolatel; meds for 6-9 months: isoniazid (INH), rifampin (RIF), ethambutol, pyrazinamide

pulmonary TB prevention (WHO recs)

early diagnosis via systematic screening & testing, vaccination, address health disparities

PPE required for treating active TB is similar to COVID-19 PPE such as…

gloves, gown, face shield, N95 mask + negative pressure isolation room

obstructuve pulmonary conditions

COPD, chronic bronchitis, emphysema, asthma; overinflation → inability to get air out of the lungs

chronic obstructive pulmonary disease (COPD) & etiology

common, preventable, tratable; persistent respiratory symptoms & airflow limitation usually from noxious particles/gases; abnormal chronic inflammatory cycle from alveolar collapse/impaired gas exchane, secretions, bronchoconstriction, pulmonary HTN, lungs hyperinflation/flattened diaphragm/hyperlucencu

COPD incidence/risk factors

3rd leading cause of death in the US commonly bc of smoking/chemical exposure, genetic predisposition w/ alpha-1 antitrypsin deficiency, childhood lung damage, air pollution

COPD common clinical manifestations

dyysnea, sputum production, poor activity tolerance, chronic cough, barrel-chested & elevated shoulders

COPD Dx & DDX

physical exam, risk factor assessment, pulmonary function tests (spirometry), hx of exacerbations, anyone over 40 w/ progressive dyspnea, chronic cough, sputum production, P/FMHx of COPD

COPD treatment

smoking cessation, pharmacologic management, airway clearance techniques, exercise, comorbidities control, improve oxygenation, reduce CO2 retention, maximize QOL, surgery to reduce lung volume, pulmonary rehab

chronic bronchitis & etiology/pathogenesis

“Blue bloaters”; productive cough at 3+ months p/year for 2 years w/ or w/o airway obstruction; inflammation & scarring of bronchial lining; mucus hypersecretion & gland hypertrophy; swollen membranes & thick sputum → obstruction, wheezing, cough, RHF

chronic bronchitis incidence/risk factors

smoking, occupational exposure to irritants

chronic bronchitis clinical manifestations

productive cough, cyanosis, overweight, prolonged expiration, recurrent infection, SOB, hypoxemia, CO2 retention, accessory breathing, air trapping, hypertrophy of mucus producing cells → excessisve sputum → obstruction

chronic bronchitis treatment

smoking cessation/reduction in irritant exposure, bronchodilators, COPD treatment

emphysema & etiology/pathogenesis

“pink puffers”; enlarged air spaces beyond terminal bronchioles → loss of elasticity in distal airways, airway collapse, gas trapping, alveolar walls destroyed & obstruction, less hypoxia, more SOB, less risk of cor pulmonale; cigarette smoking, alpha-1 antitrypsin deficient → decr ability to fight inflammation & inhibit cell death

emphysema clinical manifestations

severe dyspnea, tachypnea w/ prolonged expiration (rapid, shallow puffs), wasting appearance, bracing with arms on knees for accessory breathing, barrel chest, nocturnal hypoxemia, hyperinflation & flattened diaphragm

emphysema treatment

smoking cessation/reduction in irritant exposure, pursed lip breathing, pulmonary rehab, supplemental O2, lung transplant

asthma & types

inflammation & incr airway reactivity to stimula → bronchoconstriction & airflow resitance → bronchospasms; extrinsic (allergic), intrinsic (non-allergic), adult onset, exercise induced, occupational

asthma etiology & pathogenesis

inflammation → bronchospasm → SOB & wheezing; leukotrienes mediators produce bronchospasms, vascular congestion, edema, mucus production, impaired mucociliary function (eosinophil infiltration); progressive loss of lung function w/ each attack & structural change

asthma incidence/risk factors

younger kids, heredity, smoke exposure, maternal antibiotics in 3rd trimester, low birth weight, viral infections before age 3, low socioeconomic status, cockroach/rodent exposure in primary living areas; 11M MD visits for management in 2015

asthma Dx

clinical assessment, spirometry, pt Hx of wheezing, coughing, chest tightness, seasonal allergies, nocturnal cough, family

asthma treatment

asthma action plan to identify early symptoms; identify triggers; pt education; pharmacologic management (short-acting & long-acting bronchodilators, rescue inhalers, low-dose corticosteroids, leukotriene-receptor antagonists to inhibit inflammation)

DO NOT treat pts w/ asthma if they don’t have their ___ ___ and haven’t taking their regular inhaler ___-___ minutes before PT

rescue inhaler; 20-30

rescue/short-acting bronchodilators

smooth muscle relaxant for immediate relief of tightness, wheezing, SOB; side effect of tachycardia; anticholenergic/muscarinic antagonist, atrovent/ipratropium bromide, beta-2 agonists/sympathomimetics, Ventolin/Proventil albuterol, Xopenex/levalbuterol types

maintenance/long-acting bronchodilators

reduce airway inflammation, bronchodilate, anti-allergen, prevent bronchospasm, reduce mucus viscosity; side effects of tachycardia, hyperglycemia, OP, poor healing, prox weakness; anti-inflammatory Flovent/Pulmicort/Prednisode, anticholinergics & beta-2 agonists Spirivia, Serevent/salmeterol, Foradil; cromones/cromolyn sodium; leukotriene antagonists Zafirlukast, Montelukast; Mucolytics Mucomyst, Pulmozyme; asthma & COPD meds Symbicort, Dulera, Advair

restrictive pulmonary conditions

pulmonary fibrosis; can’t get air in

restrictive lung disease

any condition that reduces chest wall movement & lung volume → decr TLC; caused by pulmonary/extra-pilmonary causes

restrictive lung disease clinical manifestations

varies; rapid, shallow breathing, chronic tachypnea, dyspnea at rest, inadequate ventilation w/ CO2 retention, accessory breathing, hypoxemia, digital clubbing

restrictive lung disease treatment

varies; improve oxygenation, corticosteroids, heart/lung transplant'; poor prognosis

pulmonary fibrosis & etiology/pathogenesis

interstitial lug disease (ILD) w/ ongoing cycle of epithelial damage → inflammation, progressive lung scarring/fibrosis, progressive duspnea & non-productive cough, decr TLC/FVC/FEV1; 2/3 idopathic & 1/3 fibrotic after active disease, fibroblasts distort & shrink alveolar tissue/compliance, hypoxemia

pulmonary fibrosis incidence/risk factors

incr incidence despite unknown causes; smoking, biologically male, GERD, metal dust/livestock exposure, CT diseases, chemo therapy, thoracic radiation

pulmonary fibrosis clinical manifestations

SOB, dry cough, fatigue; popcorn lung, coal miner’s lung

pulmonary fibrosis treatment

2 meds (Prifenidone, Nintedanib), pulmonary rehab, supplemental O2, lung transplant

primary PT goals for pulmonary fibrosis

prevent 2ndary complications, improve QOL, remove excess secretions, maintain/improve lung function, assist w/ MSK therapy as needed

cor pulmonale & etiology/pathogenesis

pulmonary HTN, R coronary artery occlusion/infarction, tricuspid pathology, L ventricular HF → R ventricular HF; pulmonary vascular & respiratory diseases; prolonged elevation of intrathoracic pressure/mechanical vent; chronic vasculitis; incr pulmonary vascular resistance → incr pulmonary artery pressure → incr workload of R ventricles → enlargement

cor pulmonale incidence/risk factors

adult, male smokers w/ incr female incidence; 5-10% of organic heart disease

cor pulmonale clinical manifestations

drop in CO w/ exercise; weight gain, jugular venous distention, 2rd heart sound, hypotension, tachycardia, cool extremities

cor pulmonale treatment

address underlying respiratory problem, diuretics, inotropes, norepi, ECMO, VADs