Pneumonia Flashcards

1
Q

What is the basic definition of pneumonia

A

Infection in the lung

Also known as a respiratory tract infection

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2
Q

Lobar Pneumonia

A

Involvement of entire lung lobe

Typically is the end result of severe or chronic bronchopneumonia that has spread of one lung segment to another until the entire lung is involved

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3
Q

Double Pneumonia

A

Involvement of both lungs

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4
Q

Walking Pneumonia

A

Mild case of pneumonia where the patient remains ambulatory

Often caused by mycoplasma pneumoniae

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5
Q

What are the different causes of pneumonia

A

Bacteria

Viruses

Fungi,

Protozoa,

Parasites,

TB,

anaerobic organisms,

aspirations

Inhalation of irritating chemical like chlorine

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6
Q

Bronchopneumonia

A

Patchy pattern of infection limited to segmental bronchi and surrounding lung parenchyma

Usually involves both lungs

Seen more often in lower lobes

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7
Q

polymorphonuclear leukocytes

A

Will go into the alveoli with bacterial pneumonia in order to clear out the infection

Will not travel into the alveoli for interstitial pneumonia

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8
Q

Interstitial pneumonia

A

Diffuse and often bilateral inflammation that primarily involves the alveolar septa (separates adjacent alveoli) and the interstitial space

Mycoplasma pneumonia and other viruses cause interstitial pneumonias.

Most interstitial pneumonias cause only minor permanent alveolar damage and usually resolve without consequences.

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9
Q

CURB-65

A

CURB-65, is used to help predict mortality for CAP and guide where the patient shout be treated

C-Confusion

U-Blood urea >20 mg/dl

R-RR >30

B-Blood pressure with systolic <90 or diastolic <60

65-Is the patient greater than 65

If any of the above questions are answered yes, then it is considered to be one point

1 or 2 risk criteria-outpatients

2 criteria-wards

three or more risk factor should be treated in ICU

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10
Q

The risk factors for the development of HAP and VAP

A
  • Factors that interfere with hosts immunity
    • Underlying illness
    • Certain interventions (intubation or trach)
    • Meds such as sedative and corticosteroids
  • Factors the encourage exposure to pathogenic micro-organisms
    • Endotracheal or nasogastric tube
    • Contaminated equipment
    • Prior antibiotic therapy
    • Neutralization of gastric pH
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11
Q

Non-ventilated patient mortality risk with pneumonia increased when there is

A

Bilateral infiltrates

Respiratory Failure

Infection with high risk organism

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12
Q

Ventilated patient mortality risk with pneumonia increased when there is

A

Infection with high-risk organisms such as P. aeruginosa, Acinetobacter species, and Stenotrophomonas maltophilia

Multisystem organ failure

Nonsurgical diagnosis

Therapy with antacids or histamine-2 (H2)-receptor antagonists

Transfer from another hospital or ward

Renal failure

Prolonged mechanical ventilation

Coma or shock

Inappropriate antibiotic therapy

Hospitalization in a noncardiac ICU

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13
Q

Empiric anti-microbial therapy and Pneumonia

A

Empiric anti-microbial therapy is used while a definitive microbiologic diagnosis is awaited

Empiric therapy is treatment that is initiated based on the most likely cause of infection when the specific cause is unknown

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14
Q

In ~50% of patient a microbiologic diagnosis has not been made which can be attributed to

A

Inability for patient to produce sputum

The sputum acquisition is done after antibiotics has been started

There is a failure to perform routine serologic studies in all patients

Many different organisms (viruses and anaerobic bacteria) are not routinely tested for

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15
Q

fomites

A

Objects capable of transmitting infection through physical contact with them

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16
Q

what is VAP

A

VAP stands for Ventilator-Associated Pneumonia and is basically pneumonia that develops 48 hours or longer after mechanical ventilation is initiated on a patient.

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17
Q

What are the three most common gram-negative organisms associated with VAP?

A

(1) Pseudomonas aeruginosa, (2) klebsiella pneumoniae, and (3) E. Coli

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18
Q

What is the most common gram-positive organism associated with VAP?

A

Methicillin-Resistant Staphylococcus Aureus

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19
Q

What kind of secretions typically does a diagnosed VAP patient have?

A

Strong smell (purulent)

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20
Q

What fungi can cause VAP in immunocompromised patients?

A

Aspergillus

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21
Q

What is pneumonia?

A

Pneumonia is an inflammatory condition of the lungs primarily affecting the alveoli which may fill with fluid and pus. It is an acute infection of the lung parenchyma.

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22
Q

What is the assessment of viral pneumonia?

A

Low-grade fever, non-productive cough, WBC normal to low elevation, less severe than bacterial.

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23
Q

What can be assessed on patients with bacterial pneumonia?

A

High fever, productive cough, WBC elevated, chest X-ray show infiltrates more severe.

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24
Q

What medication therapy can be used for pneumonia?

A

Antibiotics, bronchodilator, and corticosteroids.

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25
What type of pneumonia is frequently undiagnosed?
Nonbacterial Pneumonia.
26
What are the three key signs of bacterial pneumonia?
Expectoration of yellow sputum, increased white blood cell count, and the presence of fever.
27
What type of anatomic alteration leads to aspiration pneumonia?
Alveolar consolidation – atelectasis – inflammation of the alveoli.
28
What term applies to the filling of alveolar spaces as a result of pneumonia?
Effusion.
29
The expression “walking pneumonia” is generally applied to patients with what type of pneumonia?
Mycoplasma pneumonia
30
What is the most commonly found bacterial cause of pneumonia?
Streptococcus pneumonia
31
What are some of the viruses that can cause pneumonia?
Influenza A or B, respiratory syncytial virus, rhinovirus, and coronavirus (SARS, MERSCoA).
32
What are some of the fungi that can cause pneumonia?
Cryptococcus, histoplasma, coccidioides, aspergillus and mucor.
33
What are some of the non-infectious etiologies of pneumonia?
Carcinomas, lymphomas, vasculitis, sarcoidosis, heart failure and pulmonary embolism.
34
What is the problem with pneumonia?
Even with antibiotics, patients with pneumonia have a high morbidity and mortality rates with the highest incidence in 1-4-year-olds or over 65.
35
What is hospital-acquired pneumonia?
This type of pneumonia is a ventilator associated and health care associated and happens at least 48 hours – 72 hours or more after admission to the hospital.
36
What is the pathophysiology of pneumonia?
1. Trigger inflammatory response-Increase blood flow and vascular permeability 2. Neutrophil activation 3. Microorganism enter alveoli 4. Extotxin produced by bacteria or cell lysis caused by viruses 5. Increased vascular permeability 6. Macrophage recruitment
37
What is the inflammatory response?
More neutrophils are activated (cascade effect) resulting to edema of the airways and fluid leaks from the capillaries to the alveoli. This affects normal oxygen transport.
38
What are the mechanical barriers from a bacterial infection?
Mechanical barriers include air filtration, epiglottis, cough reflex, and mucociliary response; reflex bronchoconstriction; and, secretion of immunoglobulins A and G and alveolar macrophages.
39
Why is antibiotic therapy beneficial for pneumonia?
Macrophages break down the bacteria and process the debris, lung tissue is allowed to recover and gas exchange returns to normal. They help to result in homeostasis and healing occurs if there are no other complications.
40
What type of pneumonia is more common in children and young adults?
Viral pneumonia.
41
What type of pneumonia is more common in adults and elderly?
Strep pneumonia.
42
What type of pneumonia is commonly found in people with HIV?
Pneumocystic jiroveci (FUNGAL).
43
What are the most common forms of pneumonia in neonates (0-1 month)?
Group B Strep and HSV.
44
What is the most common cause of pneumonia in infants (1-6 months)?
Bordetella pertussis and chlamydia trachomatis.
45
What is the most common cause of pneumonia in children (6 months – 5 years old)?
RSV and influenza.
46
What is the most common pathogen found on a young, healthy adult contracting pneumonia?
Mycoplasma.
47
What is the most common cause of pneumonia in older adults?
Strep pneumonia and H. flu.
48
What chest x-ray finding would indicate that the pneumonia will be difficult to treat and is life threatening?
Lung abscess (pus in the lung).
49
What are the atelectasis findings on a chest x-ray?
Collapse or incomplete expansion of the lung, loss of volume, Dyspnea or respiratory failure if severe and apex will usually be at the hilum.
50
What chest x-ray finding is usually associated with empyema (pus in the lung)?
Parapneumonic effusion.
51
What is a bronchogram on chest x-ray?
Air filled bronchi made visible by opacification of surrounding alveoli and peribronchial cuffing/thickening.
52
What will you usually see on a CBC with pneumonia?
Leukocytosis and L shift.
53
What should true sputum show when trying to find the cause of pneumonia?
An abundance of inflammatory cells, no squamous epithelial cells and large numbers of a single organism.
54
What pattern of pneumonia will have entire lobe consolidation and is commonly caused by Klebsiella?
Lobar. It can usually be seen in bronchograms too.
55
What pattern of pneumonia is multifocal and patchy and usually seen with staph, strep, and h. flu pneumonia?
Bronchopneumonia
56
What pattern of pneumonia is caused by viruses?
Interstitial that is characterized by a ground glass appearance.
57
What are the four most common symptoms of pneumonia?
Productive cough, shortness of breath, chest pain, fevers and chills.
58
What are the typical and atypical organisms associated with community-acquired pneumonia?
Typical involves S pneumoniae (pneumococcus), which is the most common cause requiring hospitalization, Haemophilus and Staphylococcus species. While atypical is caused by legionella, mycoplasma, chlamydia species and pneumocytis jiroveci (associated with HIV diagnosis).
59
What factors impair pulmonary clearance of pneumonia?
Viral upper respiratory tract infection, smoking, alcohol, uremia (raised levels of urea and other nitrogenous waste compounds in the blood), and bronchial obstruction.
60
What is the difference between typical (virulent) and atypical pneumonia?
Typical has an abrupt onset characterized productive cough with purulent sputum, pleuritic chest pain, impressive physical findings, leukocytosis with left shift or leukopenia, abdominal pain and high fever. This type responds to beta-lactams. While atypical has a gradual onset that presents nonproductive/dry cough, sub-sternal chest pain, unimpressive physical exam, WBC count normal (no left shift), and nonspecific symptoms (headaches, malaise, nausea, vomiting, diarrhea, interstitial or patchy infiltrate). This type responds to macrolides and quinolones.
61
What indications are observed to determine the type of organism that caused the pneumonia infection?
Patients are observed by their chills, relative bradycardia and sputum. For chills, a single chill suggests S. pneumoniaewhile multiple chills suggest S. aureus or K. pneumoniae. For relative bradycardia, association with viral infection, mycoplasma pneumonia, psittacosis, tularemia, and legionella spp. Sputum is identified if rust-colored sputum or currant-jelly. Rust-colored sputum suggests association with infection by S. pneumoniae while currant-jelly sputum is associated with infection by Klebsiella species. Foul-smelling or bad-tasting sputum is often produced by anaerobic infections.
62
Pneumonia Definition
Pneumonia is the result of an inflammation process that primarily affects the gas exchange of the lungs In response to inflammation fluid (serum) and RBC from adjacent pulmonary capillaries will pour into the alveoli (this fluid transfer is known as effusion) 8th leading cause of death
63
Consolidation in the Lungs
When an infection is overwhelming the alveoli will become filled with fluid , RBC, leukocytes, and macrophages When this happens the lungs are considered to be consolidated When this happens the alveolar structure will be maintained meaning that after the pneumonia has been resolved there will be minimal residual destruction to the parenchyma
64
Pneumonia as a Insidious Disease
Pneumonia is an insidious disease as symptons depend upon underlying condition and organism causing pneumonia
65
High Risk Groups for Pneumonia
Seen in the hospital with other co-morbidities, but anyone can get pneumonia High-risk groups for pneumonia * COPD * HIV * Altered LOC/dyspnea/dementia * Patient undergoing chemotherapy * Intubated * Recent Surgery * Paraplegic * Pregnant * Alcoholics
66
Anatomical Alterations of the Lungs
Inflammation of Alveoli Alveolar Consolidation-Blocks alveoli Atelectasis-E.g. Aspiration pneumonia Increased Alveolar Capillary Membrane Thickness Excessive Bronchial Secretions-During resolutions phase
67
Bronchopneumonia
Inflammation in the bronchi Bilateral
68
Lobar Pneumonia
Involvement of entire lung lobe Widespread in the alveoli
69
Double Pneumonia
Involvement of both lungs Bilateral
70
Walking Pneumonia
Mild case of pneumonia Typically mycoplasma pneumonia Patient remains ambulatory
71
Gram-Negative Organism
* **Haemophilus Influenzae** * **Klebsiella** * Pseudomonas Aeruginosa * 1st degree killer * Primary killer in hospital pneumonia *
72
Gram-Positive Organism
Streptococcus-Most common community pneumonia Staphylococcus-Most common hospital acquired (E.g. MRSA)
73
Bacterial Causes
Alveolar exudates will be mainly composed of neutrophils It is important to promptly get a gram stain and culture analysis Can be gram positive or gram negative
74
Atypical Organism
Organism escapes standard identification from bacterial test Moderate sputum Absence of alveolar consolidation Only moderate WBC elevation Lack of alveolar extubate
75
Atypical Organism Types
* **Myocoplasma Pneumoniae** * Most common acquired atypical pneumonia * Walking pneumonia * **Legionella Pneumonia** * Found in hot tubes * Middle age smokers * **Chamydia Osittaci** * School aged children * **Chlamydia Pneumoniae**
76
Viral Causes
Viral cases account for 50% of pneumonia cases Influenza A and BVirus Respiratory Syncytial Virus (RSV)-Tends to affect children younger than one year, with a seasonal presentation Parainfluenza Virus-Affects all ages and will spread quickly Adenovirus-Affects all ages with a high morbidty in children Coronavirus (SARS) H1N1 (Swine Flu)
77
Other Causes of Pneumonia
Rickettsial Infections Varicella Rubella Aspiration Pneumonitis Lipoid Pneumonitis Immuno-comprimised Patients AIDs Patients Tuberculosis Fungal infections Avian Influenza A
78
Cryptogenic Organizing Pneumonia (COP)
Unknown cause No consolidation Appear with history of dry cough Inflammatory process Treated with steroids Rare and very severe Can reoccur
79
Acquired Pneumonia Classifications
Community-Acquired Pneumonia (CAP) Nursing home acquired pneumonia Hospital-Acquired Pneumonia Ventilator-Associated Pneumonia
80
Community Acquired Pneumonia-Typical Acute Forms
Streptococcus Pneumoniae Haemophilus Influenza Moraxella Catarrhalis Staphylococcus Aureus
81
Community Acquired Pneumonia-Chronic Forms
**Mycobacterium tuberculosis** Histoplasma capsulatum Coccidiodes Immitis Blastomyces Dermatiditis
82
Immuno-Comprimised Host
Pneumocystic Carinii Cytomegalovirus Aspergillus Species (Fungal) Cryptococcus Neoformans (Yeast) Re-Activation of Tuberculosis or Histoplasmosis
83
Aspiration
Not always nosocomial Patients with GERD (asthma, pregnant) will be more acidic when they aspirate which also puts them at greater risk for ARDS Trach patients will have difficultly swallowing which will put them at a higher risk for aspiration pneumonia (especially when the cough is inflated) Mixed aerobic and anaerobic species Enteric-Normal gram negative Staph Aureus
84
Mendelson’s Syndrome
Clinical picture of aspiration pneumonitis in pregnant women Include tachypnea, dyspnea, and cyanosis
85
Silent aspiration
Aspiration that does not evoke observable adverse symptoms
86
Ventilator Associated Pneumonia
Most common nosocomial infection **Pseudomonas Aeruginosa**-1 Degree Killer Acinetobacter Species Enterobacter Species **Klebiella** **Staphylococcus Aureus** Moraxella Catarrhalis
87
Typical Process of Pneumonia
1. Begins with alveoli filled with exudate and pathogen (edema) 2. Early consolidation RBC and neutrophils 3. Severe consolidation, phagocytation by polymorpho-nuclear neutrophils, PMNS 4. Resolution macrophages replace neutrophils, debris clean up
88
Lung Exudate
Exudate: A fluid rich in protein and cellular elements that oozes out of blood vessels due to inflammation and is deposited in nearby tissues.
89
Streptococcal Pneumonia Treatment
Most strains are sensitive to **pencillin** and its derivities
90
Streptococcal Pneumonia Onset
Will tend to begin in the upper airway (URT infection) and then move down Will have an abrupt onset with a cough, shaking, and chills
91
Streptococcal Pneumonia
Gram positive Accounts for over 80% of bacterial pneumonia The bacteria is enclosed in a sugar jacket (polysaccharide) which accounts for their virulence (how fast and aggressive they spread) Splinting (immobilization) causes a low tidal volme and tachypnea Mixed red and grey hepatization Fibrinous pleural exudate
92
Streptococcal Pneumonia Sputum
Rusty color sputum from hemorrhagic caps
93
Streptococcal Pneumonia Transmission
Aerosol Cough, Sneeze
94
Streptococcal Pneumonia Breath Sounds
Fine crackles, pleural rub,
95
Staphylococcal Pneumonia Breath Sounds
Coarse and medium crackles
96
Staphylococcal Pneumonia Clinical Presentation
High fever Hemoptysis Pleuriti adhesions Etiology has a definite respiratory componenet
97
Staphylococcal Pneumonia
Gram positive The patient will often need to be intubated Will often be nosocomial as it is the main hospital acquired pneumonia Origin on normal flora of humans Half the population are carrier, but it is rare to see this as a community acquired disease unless there is a influenze outbreak, as it often follows a predisposing viral infection (super infection after a viral insult) Can cause emphysema, cavitation, abscess, potential pneumothorax on the lung and endocarditis and tri cuspid lesions and the heart Often seen in children and immunosuppressant adults There is a high mortality rate due to the complexity of the disease
98
Staphylococcal Pneumonia Types
Staphylococcal Aureus-Most virulent Staphylococcus Epidermidis-In the normal flora of the skin
99
Staphylococcal Pneumonia Treatment
Methicillin-Susceptible Strains-Nafcillin Methicillin-Resistant Strains-Vancomycin This is very difficult to treat and often we need to conslt a specialist
100
Staphylococcal Pneumonia Transmission
Aerosol-Cough On any surface after a viral infection
101
Klebseiella (Friedländer's)
Gram Negative Commonly seen in diabetics, the homeless, alchoholics, trach pt. and men over 40 Sudden onset Hemptyosis There is a significant mortality rate as it can lead to septicemia Often nonsocomial Can be misdiagnosed as TB due to abscess formation 1st or 2nd super infection pathogen looks like currant jelly sputum
102
Klebseiella (Friedländer's) Transmission
Can be aerosol but more likely is contact from food and unclean hands
103
Klebseiella (Friedländer's) Origin
Fecal/oral route Normal flora of GI tract Aerosol
104
Klebseiella (Friedländer's) Treatment
3rd or 4th Generation Cephalosporins (ceftazidime, ceftriaxone) Aminoglycoside Antipseudomonal Penicillin Monobactam (aztreonam) Quinolone
105
Klebseiella (Friedländer's) Resolution
Resolution Will have a large number of organisms such as necrotizing and fibrin (scar) producing elements during the resolution
106
Pseudodomas Aeruginosa
Gram negative Can be confused with flesh eating disease Can be seen in ICU with pt. who are immuno comprimised
107
Pseudodomas Aeruginosa Tranmission
Aerosol or freshly contaminated surfaces Often will be nosocomial and due to respiratory equipment (ex. Trachs) Often cultured especially in aquesouns solution (loves dampness)
108
Pseudodomas Aeruginosa Origin
Normal GI flora Meaning wash your hands after you use the bathroom
109
Pseudodomas Aeruginosa Treatment
Trobramycin
110
Pseudodomas Aeruginosa Sputum
Copious production Greenish Sweet smelling sputum
111
Pseudodomas Aeruginosa Clincal Presentation
Fever Rigors Abscesses
112
Pseudodomas Aeruginosa Mortality Rate
High Mortailty rate
113
Haemophilus Influenza
Smallest gram negtaive often seen secondary to a viral infection With a severe infection there is a 30% mortality rate
114
Haemophilus Influenza Transmission
Aerosol Recently contaminated surfaces-It does not liek the cold and will not last long out side of the body (not easy to transmit) The above are also the origin of the disease
115
Haemophilus Influenza Treatment
Ampicillin
116
Haemophilus Influenza Affected Populations
Commonly seen in small children where it can cause acute epiglottitis Also seen in pt. with COPD, alchoholics,
117
Haemophilus Influenza Clinical Presentation
Low leve cough Fever Will grow to dyspnea-Not a fast acting disease Purulent spurum Patchy infiltrates on x-ray
118
Viruses
Non-living pathogens Parasites that are dependent upon living cells for nutrition and replication Have protein spikes on their surface which will match to receptor sites on specific cells (designation H and N) These spikes can facilitate penetration of the usually intact cell membrane and allow viruses to either inject RNA or the entire viral packet into the cell Once inside the cell the viral RNA will force copes of itself to be made Viruses will often kill the host cell through using up all the cells nutrients and proteins and initiating over production of RNA packets which will lead to burst of the cell membrane
119
Influenza Viral Pneumonia
Severe parencyma congestion, hemorrhage, edema, consolidation, and emphysema The A/C membrane will thicken by the edema, capillaries will engore, alveoli filled with type I and II cells leukocytes, and macrophages (fibrin producing) Can be diagnosed though symptons and a rapid antigen test will can produce results in 15 min but is high in false negatives
120
Criteria for Severe Designation
1. RR over 30 at rest 2. PaO2 less than 60 on 30% or more O2 3. Multiple lob involment 4. Shocky; 5. Low BP; systolic under 90 and diastolic under 60 6. Low Urine Output-Less than 20 ml/hr
121
General Physical Examination
Vital signs-Tachycardia, tachypnea, increase blood pressure Chest pain and decreased chest expansion-Moved to pleural space and painful cyanosis cough, sputum, hemoptysis Confusion and mood change (may mean septic shock) Nausea and vomitting
122
Chest Assessment
Incresed tactile and vocal fremitus dull percussion bronchial bretah sounds throughout crackles and wheezes pleural friction rub-if in pleural space increased whispered pectoriloquy
123
Pulmonary Function Test
Restrictive
124
Arterial Blood Gases- Severe Stages
Acute Alveolar Ventilation with hypoxemia Acute Respirtory Acidosis
125
Arterial Blood Gases- Mild to Moderate Stages
Acute Alveolar hyperventilation with hypoxemia Acute Respirtory Alkaslosis
126
Oxygenation Indices
Pulmonary shunt (Qs/Qt)
127
Chest Radiograph
Increased density (from consolidation and atelectasis) Air Bronchograms Pleural Effusion
128
General Mangement of Pneumonia is Based Upon
Specific etiology of the Pneumonia-Bacteria, Virus, Aspiration Severity of Symptons
129
Fungi-Causes
Aspergillus Species Cryptococcus Neoformans Cardida Species
130
Bacterial Causes- Types
Streptococcus Pneumonia Staphylococcus Aureus Hemophilius Influenza Pseudomonas Aerginosa Kledsiella Pneumonia Legionella Species Mycoplasma Pneumonia Chalmydia Species
131
Types of Protozoa
Pneumocystis Carinii