3. +
Hypoxemia
Defined as PaO2<60mmHg
Etiology
V/Q mismatch
Airspace not being perfused OR perfused areas not being ventilated
Etiologies: asthma, COPD, PE, interstitial lung disease
Management: oxygen and treat underlying cause
Shunting
Decreased diffusion of oxygen
Etiologies: alveolar collapseARDS, also from alveolar filling
(pneumonia, pulmonary edema)
Management: does NOT respond well to oxygen responds better
to PEEP
4. +
Hypoxemia
Decreased diffusion
Etiologies: thickening of alveolar/capillary interface (commonly
interstitial lung disease)
Management: responds to O2
Hypoventilation
Lack of respiratory effort resulting in low PaO2 and high PaCO2,
commonly from drug overdose
Normal A-a gradient
High Altitude
Decrease in partial pressure of available O2
Normal A-a gradient
5. +
Critical Care: ARDS
Acute onset of alveoli edema caused by capillary membranes
injury and increased permeability
Sepsis, acute pulmonary infection, DIC, shock lung, freebase
cocaine smoking
You will see bilateral infiltrates on chest x-ray
Ratio of PaO2/FiO2<200mmHg
Symptoms: respiratory distress, hypoxemia unresponsive to
increasing supplemental O2
Onset is often within the first 2 hours of inciting event, but it can
be delayed as long as 1-3 days
6. +
Critical Care: ARDS
Management
35-50% mortality
Treat underlying disease
Mechanical ventilation with PEEP
Use low tidal volumes to prevent barotrauma
Steroids NOT shown to be beneficial
7. +
Disorders of Pleura, Mediastinum
and Chest Wall
Mediastinitis
Pneumomediastinum
Pleural Effusion
Pneumothorax
8. +
Mediastinitus
Inflammation of the mediastinum
Etiology
Mixed organisms but most commonly Streptococcus and
Bacteroides
Esophageal rupture most common cause (foreign body ingestion or
stuck fish bone may accompany history or esophageal inj)
Risk Factors
Immunocompromise and diabetes, drug abuse
Symptoms
Fever, dyspnea, pleuritic, retrosternal chest pain, sub-q emphysema
of neck and chest
9. +
Mediastinitis
Diagnosis
Soft tissue x-ray of the neck may show precervical or
retropharyngeal air/edema
A CXR may show a widened mediastinum
CT should be performed to further evaluate soft tissue spaces
Management
Broad-spectrum antibiotic therapy
ENT and cardiothoracic consult
10. +
Pneumomediastinum
Etiology
Spontaneousextremely rare, blunt chest trauma, endoscopy,
obstructive lung disease
Considerer Boerhaave syndrom if h/o vomiting
Valsalva maneuver (foreceful cough against a closed glottis,
consitpation)
Observed in crack cocaine users
Symptoms
Chest pain and dyspnea
Signs: sub-q emphysema and Hamman sign (crunching, rasping
sound, synchronous with heartbeat)
Decreased cardiac output if tension pneumomediastinum is present
11. +
Pneumomediastinum
Diagnosis
Esophagogramperform in right lateral decubitus position, use a
water-soluble contrast, if clinical suspicions remain high and the
initial study is negative, repeat study with oral barium contrast
Esophagoscopyfor suspected esophageal rupture in acute
traumatic rupture
CXRreveals free air within the mediastinum, air posterior to
sternum and posterior to the heart on lateral film
Bronchoscopyfor suspected bronchotracheal tree rupture
Management
Should be admitted and observed for signs of serious complications
Broad-spectrum antibiotics for suspected esophageal rupture
12. +
Pleural Effusion
Collection of fluid within pleural space
Epidemiology
CHF is the most common cause followed by malignancy, bacterial
pneumonia, and PE
TB is the most common etiology of pleural effusion in developing
countries
Etiology
TransudativeCHF, cirrhosis with ascites, nephrotic syndrome, PE
ExudativeCancer, infectious (pneumonia, empyema, abscess,
TB), inflammatory (SLE, pancreatitis, RA, and PE
13. +
Pleural Effusion
Symptoms
Dyspnea and pleuritic chest pain, decreased breath sounds on
auscultation, dullness to percussion
Diagnosis
CXR: AP XR demonstrates effusion when pleural fluid volume
approaches 150cc
CT or US most sensitive
Thoracentesis necessary when etiology is unclear
Light criteriaa single positive criterion is enough to classify the fluid
as an exudate
Glucoselow pleural fluid levels (<25)=RA, TB, empyema, and
malignancies
pHlow pH=inflammatory and infiltrative processes (empyema,
malignancies, TB, esophageal rupture)
Amylasehigh amylase (>200) pancreatitis, malignancy, rupture
17. +
Pneumothorax
Symptoms
Dyspnea and pleuritic chest pain
Decreased breath sounds and hyperresonace to percussion
JVD and hypotension
Tracheal deviation away from affected side
Diagnosis
Pneumothorax
CXR for simple pneumothorax (end expiratory for highest sensitivity)
CT test of choice for supine trauma patient
Tension pneumo
Clinical diagnosis
Tracheal deviation away from affected lung
Hypotension
Do NOT wait for x-rays before treating
18. +
Pneumothorax
Management
Small, stable ptx (<10%)
Reabsorb 5-7% per day
100% O2
Stable patient with a small ptx can be discharged with next day
follow up after 6 hours observation and stable x-ray
Large ptx
100% O2
Tube thoracostomy
Tension ptx
Immediate decompression followed by chest tube
19. +
Noncardiogenic Pulm Edema
Definition: radiographic evidence of alveolar fluid accumulation
without hemodynamic evidence of a cardiogenic etiology (ie
pulmonary capillary wedge pressure <18mmHg)
Etiology
ARDS
High-altitude pulmonary edema
Reexpansion pulmonary edema
Large volume thoracentesis (>1L)
Rapid lung re-expansion of ptx, especially when it has been
collapsed for >3 days
Drug induced (meprobamate, opiates, naloxone, PCP, Salicylate)
21. +
Asthma and reactive airway disease
Chronic inflammatory disorder of the small airways characterized
by reversible obstruction
Etiology and patho
Airway inflammation/bronchial wall edema leading to decreased airway
diameter
Airway hyperreactivity, smooth muscle contraction
Secretions forming mucous plugs
Chronic inflammation leads to lung remodeling
Symptoms
Dyspnea with or without cough
Prolonged expiratory phase with predominantly exp wheezing
Severe exacerbations may present with absence of wheezing, inability
to speak, pulses paradoxus and hypoxia
22. +
Asthma and reactive airway disease
History associated with higher mortality
>2 hospitalizations during past year
>3 ED visits during past year
Prior intubation or ICU admission
Use of 2 or more adrenergic canisters per month
Current use of systemic steroids or recent withdrawal
Low socioeconomic class
23. +
Asthma and reactive airway disease
Diagnosis
Bedside spirometrypeak flow to monitor response to beta-agonist
treatment
Peak flow <50% indicates severe exacerbation
Treatment
Oxygen to keep O2>88%
Beta agonistsrelaxation of bronchial smooth muscle
Epinephrine (1:1000)reserved for severe exacerbations, is
administered sub-q 0.3 q20-30 minutes up to three doses
Terbutaline reserved for severe exacerbations given SC 0.25mg
every 20-30 min up to three doses
Longer duration of action than epinephrine
24. +
Treatment cont.
Corticosteriodsused in both acute and chronic setting to
prevent late phase inflammatory response
Oral dosing as effective as IV administration
Magnesiumbenefit in severe exacerbation
Mechanical ventilation
Avoid air-trapping or auto-peep
Smaller tidal volumes
Keep rate low
Consider increasing peak inspiratory flowlonger expiratory time
25. +
Treatment cont
When treating pregnant asthmatics…
Fetus more susceptible to hypoxia than mother
No contraindications to use of beta agonists, corticosteroids and
anticholinergics
Chronic steroids may result in lower birth weights
Epinephrine is teratogenic during first trimester and associated with
preterm delivery
26. +
COPD
Progressive partially reversible limitation of airflow
Caused by two processeschronic bronchitis and
emphysema, which occur together in most patients
Epidemiology
The single most important risk factor for COPD is smoking
Etiology
80% of acute COPD exacerbations are of infectious origin
Streptococcus pneumoniae, Haemophilus influenzae, or
moraxella catarrhalis
27. +
COPD
Signs and symptoms
Dyspnea on exertion, tachypnea, cyanosis, agitation, apprehension,
and hypertension are indicative of hypoxia
Wheezing, rales, rhonci, prolonged expiratory phase, pursed-lip
breathing and clubbing of digits
Diagnosis
Elevated hematocrit 2/2 chronic hypoxia
ABG: mild to moderate hypoxemia without hypercapnea in early
stages
CXRhyperinflation, flattened diaphragm, long narrow heart
shadow
EKGa-fib, multifocal atrial tachycardia, cor-pulmonale (tall pwaves), right axis deviation and right ventricle hypertrophy
28. +
COPD
Management
Supplemental oxygen reduces mortality in patients with advanced
COPD with room air O2 saturaion <88%
Nebulized anticholinergics
Bronchodilators
Antibiotics
First line choices include amoxicillin, cefaclor, fluoroquinolones, or
bactrim
Gram-negative infections more likely in those with frequent
exacerbation and need a third-generaltion cephalosporin
corticosteroid
29. +
Cystic Fibrosis
Most common in Europeans and Ashkenazi Jews
Autosomal recessive mutation
Abnormalities in chloride transport in exocrine tissues leads to
multiorgan involvement
Thick, viscous secretions in lungs, intestine, pancreas, and
reproductive tract
Symptoms and signs
Respiratory manifestationsmost common, exacerbations
characterized by increased cough, sputum production, decreased
lung function
30. +
CF symptoms and signs cont.
Undiagnosed patients may present with failure to thrive chronic
cough, repeated pulmonary or sinus infections, chronic
diarrhea from pancreatic insufficiency
Alternative presentations
Increased salt content in sweat gland secretion
Meconium ileus in neonates
Steatorrhea from pancreatic enzyme insufficiency
Intestinal obstruction
Spontaneous pneumo
Chronic pancreatitis
Hepatobiliary disease
31. +
CF diagnosis
Electrolytes
Hyponatremia and alkalosis
CXR
Bronchiolar thickening, hyperinflation, and patchy, diffuse infiltrates
Newborn screening
Chloride sweat testing or genetic testing
32. +
CF Management
Broad-spectrum antibiotics
Cover Staph aureus, H. flu, and double cover Pseudomonas
Chronic colonization with pathologic bacteria and chronic antibiotic
use leads to resistant organisms requiring intravenous vanco,
tobramycin, meropenem, cipro, and piperacillin
Mucolytics
Bronchodilators
Aggressive chest physiotherapy
Provide O2
Consult Pulm
33. +
Restrictive Lung disease
Loss of lung compliance resulting in volumes loss
Interstitial Lung Disease
Idiopathic pulmonary fibrosis
Sarcoidosis
34. +
ILD
ILD
Restrictive pulmonary dysfunctions with the common end-point of
interstitial collagen deposits and scarring
Idiopathic pulmonary fibrosis
50% of ILDs
Likely autoimmune
Symptoms and signsdyspnea, cough, fine dry crackles, clubbing
of fingers
DiagnosisCXR has honeycombed lungs, CTground glass
opacity
Management corticosteroids, immune modulators, lung transplant
40. +
DVT
Risk factors
Previous thrombosis
Vascular endothelial damage
Trauma, sugery (especially ortho), smoking
Hypercoagulability
Factor V Leiden (most common hereditary hypercoagulability
Antithrombin III deficiency
Protein C or S deficiency
Oral contraceptives or 3rd trimester pregnancy
Immobilization or low cardiac output
Long periods of sitting, CHF
42. +
DVT
Diagnosis
CT angiography
Doppler ultrasonography
Limitationsoperator dependent, cannot distinguish between old
and new clot, not accurate in detecting DVT in the pelvis or the
small vessels of the calf
Management
Anticoagulationunfractionated low-molecular weight heparin or
warfarin therapy
Filter placement for patients with failure of anticoagulation or
contraindication to anticoagulation
43. +
Pulmonary Embolus
Risk factor are the same as for DVT 60% of patients with a
DVT have a PE
Symptoms and signs
Sudden-onset dyspnea, tachypnea, tachycardia, pleuritic pain,
hemoptysis, syncope, cough, and wheeze
44. +
PE diagnosis
ECG
Nonspecific ST-T wave changes and/or sinus tach are most common, S1Q3T3,
precordial flipped T waves
CXR
Findings are abnormal but nonspecific, pleural effusion, elevated hemidiaphragm
secondary to atelectasis and noninfectious infiltrates
Westermark signabrupt cut-off of vascular markings
Hamptom humppleural based wedge-shaped infarct
CT pulm angiography
VQ scanuseful in severe contrast allergies
A normal scan is sufficient to exclude PE in patient with low pretest probability
Echomay reveal evidence of right heart strain
Pulmonary angiographythe gold standard for diagnosing PE (used
infrequently because of noninvasive CT scans
45. +
PE management
Supplemental O2
Hemodynamic support
Anticoagulation
Thrombolytic
Indicated in patients with associated hemodynamic instability
Surgical Embolectomy
IVC filter for anticoagulation failure or contraindication
47. +
Bacterial Pneumonia
Etiology
Typical Pneumonia
S. pneumoniae, H. influenzae, and Staph (S. Pneumo most
common)
Atypical Pneumonia
Influenza virus, mycoplasma, chlamydia, legionella, and
adenovirus
IV drug usersS. aureus
Alcoholism, diabetes, and COPDK, Pneumoniae
AsthmaticsH. Flu
Hospital acquired pneumoniapseudomonas aeruginosa
48. +
Bacterial Pneumonia
Symptoms and signs
Chest pain
Productive cough
Klebsiellacurrant jelly
S. Pneumoniaebloody or rusty colored
Aspirationfoul-smelling sputum
Chlamydiastaccato cough
Rigorsparticularly associated with S. Pneumonia
Diarrhea and GI upset with Legionella
Bullous myringitis with Mycoplasma pneumoniae
Pleural rubs
49. +
Bacterial Pneumonia
DiagnosisChest radiography
Bilateral diffuse infiltrates consistent with atypical infections (M.
Pneumoniae, P. Carinii, C. Psittaci)
Abscess and bulging lung fissures are indicative of infections
caused by Klebsiella and S. aureus
Pleural effusions and empyema associated with cavitary lesions are
seen with s. aureus and M. tuberculosis
Upper lung fieldsK. Pneumoniae
Lower lung fieldsL. Pneumoniae
Miliary patternM. Tuberculosis
50. +
Bacterial Pneumonia
Laboratory studies
Hyponatremia and hypophosphatemia associated with L.
Pneumophila
Sputum samples for gram stain and culture are accurate about 50%
of the time
Adequate sputum contains <10 epithelial cells, >25 WBC per low
power field and remain uncontaminated from oral flora
Mycoplasma and Chlamydia immunoglobulin M antibodies a
rise in antibody titer of 1:128 confirms the diagnosis
51. +
Bacterial Pneumonia
Management
Community-acquired pneumonia
Pneumonia severity index score helps determine risk
Admit if total score >90 points and consider ICU for >130
Hospital-acquired pneumonia
Double-drug coverage for Pseudomonas
Optimal combinations include cefipime plus levofloxacin,
aztreonam, meropenem, or aminoglycoside
Aspiration pneumonia
Intubation should be considered in any patient who is unable to
protect airway, add anaerobic coverage
52. +
Types of Bacterial Pneumonia
Bordetella Pertussis (whopping cough)
Summer and fall months, neither active disease nor vaccination
provides lifelong immunity
Symptoms and signs3 stages, each lasting about 2 weeks
Catarrhal
Paroxysmal
Most infectious during this time, symptoms indistinguishable from
a URI
Coughing episodes followed by an inspiratory “whoop” , posttussive exhaustion and emesis
Convalescent
Chronic cough that can last several months
Complications include mucous plug, secondary bacterial infection,
ruptured diaphragm, hernia, and rectal prolapse
53. +
Pertussis
Diagnosis
Degree of lymphocytosis correlates with severity of disease
Definitive diagnosis is made via nasopharyngeal culture
Treatment
Erythromycin x14 days
Consider prophylaxis with erythromycin for close contacs
Consider hospitalization for infants <6 months, premature infants,
and those with significant comorbitites
54. +
Mycoplasma Pneumonia
Most common atypical
14-day incubation period
More common in young adults
CXR may show interstitial pattern or patchy infiltrate
Treat with macrolide antibiotic
Associations
Bullous myringitis
Meningitis and encephalitis
Erythema multiforme
Guillain-Barre
55. +
Chlamydia Pneumonia
Obligate intracellular parasite
Infants
Acquired at birth
50% conjunctivitis
Tachypnea
May be afebrile
CXR shows hyperinflation and diffuse infiltrates
Common in young adults complaining of hoarseness, cough, and
persistent malaise
Staccato cough
Treat with macrolide
56. +
Legionella Pneumonia
Airborne and associated with water sources
Classically associated with recent air travel
No person to person transmission
Symtpoms and signs
Pleuritic chest pain, relative bradycardia, GI symtpoms
Diagnosis
Labs may reveal hyponatremia and hypophosphatemia
Chest x-ray may show alveloar infiltrates or consolidation that my
progress to hilar adenopathy and pleural effusion
Treat with erythromycin for 3 weeks
57. +
Tuberculosis
Leading cause of death worldwide
Humans are sole reservoir
TB can remain dormant for years in granulomas
Risk factors
Immunocompromised (HIV, malignancy, DM, extremes of age)
Close contacts or occupational exposure
Medically underserved, low-income populations
58. +
TB symptoms and signs
Primary TB
Only 10% of exposed individuals develop primary TB
Constitutional symptoms
Coughmost common symptoms of pulmonary TB
Initially nonproductive or nonspecific sputum
Hemoptysis may be presenting complaint
Pleuritic chest pain
Night sweats
“classic” presentation is uncommon
59. +
TB
Postprimary TB (reactivation TB)
Lifetime risk in immunocompetent individual is 10% to 15%
In HIV-positive patients
37% with disease in 6 months
10% incidence of disease per year
Signs and symptoms similar to primary TB
60. +
TB extrapulmonary
Lymphadenitis (scrofula)
Pleural effusion
Pott’s disease (spinal)spinal cord injury possible, lumbar infection may lead to
psoas abscess
acute disseminated
Small and unilateral, diagnosis through pleurocentesis
Bone and joint infection
Most common EPTB, enlarging, painless, erythematous firm mass near cervical
nodes, do NOT I and D
Generalized systemic illness, typically in elderly and HIV patients, fever, weight
loss, anorexia, weakness, SIADH is common, often associated with meningitis
CNS
6% of cases, peak in newborn to 4 years, SIADH, tuberculosis meningitis
CSF analysislowest glucose CSF levels of any meningitis
61. +
TB diagnosis
TB skin testingread 48-72 hours later, induration not
erythema
15mm in low-risk, immunocompetent patients
10mm in high-risk immunocopetent patients
5mm in HIV, Close contacts infectious TB, abnormal CXR,
immunocompromised from steroids
62. +
TB medical therapy
Latent TBinfections without active disease,
chemoprophylaxis with isoniazid for 9 months
Active TBtreated for 6 months, 4 drugs until resistance
pattern determined, after 2 months may discontinue
pyrazinamide if TB isolates do not demonstrate resistance
Extrapulmonary TB->treat for 6 months
CNS infection (tuberculous meningitis) is the exception, requires 912 months of treatment
Consider steroids for CNS and pericardial TB
63. +
Treatment of TBdrugs
First line agents
Isoniazid (INH)
8% resistance rate
Prevent INH-related seizures: supplement with pyridoxine (B6)
Rifampin
Orange discoloration of bodily fluids
Oral contraception failure
Pyrazinamide (PZA)
Hepatotoxicity, polyarthralgias
Ethambutol (ETH)
Prevents emergence of RIF resistance
Retrobulbar neuritisdecreased visual acuity or red/green color
blindness
64. +
Treatment cont.
Noncompliant patients
Court-ordered directly observed therapy (DOT)
Uncooperative and potentially infectious patients may be compelled
to comply
Incarceration as last resort
In pregnancy
INH, RIF, ETH cross placenta and are safe
66. +
influenza
Often associated with bacterial superinfection (s. aureus)
Diagnosis: nasopharyngeal swab culture for influenza aid
diagnosis
CXR shows diffuse bilateral infiltrates
67. +
Varicella
Symptoms and signs: pneumonia may present with chest pain
and hemoptysis preceded by a rash
More severe in adults
Managementmandates admission for treatment with
acyclovir
68. +
cytomegalovirus
Most common in solid organ transplant and bone marrow
transplant recipients
Often presents simultaneously with pneumocystis pneumonia
Management
IV ganciclovir or foscarnet plus immunoglobulin therapy
CXR
Bilateral interstitial pattern
69. +
Hantavirus
Aerosolized contaminated material from rodent feces or urine
Southwest US
Symptoms and signsflu-like symtpoms that progress to
respiratory distress and shock
DiagnosisCXR reveals bilateral infiltrates
70. +
Fungal Pneumonia
Histoplasma capsulatum, blastomyces dermatitides and
coccidioides present in the soil in various geographic areas of
the US
Histoplasma capsulatum in the mississippi and Ohio River valleys
Coccidioides immitis in desert areas of the Southwest
Symptoms and signs vary from acute or chronic pneumoina to
asymptomatic granulomas on CXR
Diagnosishilar adenopathy