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Pneumonia (Des Jardins) for midterm.

Anatomic Altera­tions of the Lungs

Pneumonia or pneumo­nitis with consol­idation
The result of an inflam­matory process that primarily affects the gas exchange area of the lung.
Sequence of Events
Fluid (serum) and some red blood cells (RBCs) from adjacent pulmonary capill­aries pour into the alveoli.
Surface Phagoc­ytosis
Polymo­rph­onu­clear leukocytes move into the infected area to engulf and kill invading bacteria on the alveolar walls.
Increased numbers of macrop­hages also appear in the infected area to remove cellular and bacterial debris.
If the infection is overwh­elming, the alveoli become filled with fluid, RBCs, polymo­rph­onu­clear leukoc­ytes, and macrop­hages.
Atelec­tasis is often associated with patients who have aspiration pneumonia.
Major pathologic or structural changes
Inflam­mation of the alveoli
Alveolar consol­idation
Atelec­tasis (e.g., aspiration pneumonia)

Etiology and Epidem­iology

Pneumonia and influenza
eighth leading cause of death among Americans
sixth leading cause of death over the age of 65 years
especially life threat­ening in indivi­duals whose lungs are already damaged by chronic obstru­ctive pulmonary disease (COPD), asthma, or smoking
The risk of death from pneumonia orinfl­uenza is also higher among peoplewith heart disease, diabetes, or a weakened immune system.
Causes of pneumonia
bacteria, viruses, fungi, protozoa, parasites, tuberc­ulosis, anaerobic organisms, aspira­tion, and the inhalation of irritating chemicals such as chlorine
is an insidious disease because its symptoms vary greatly, depending on the patient’s specific underlying condition and the type of organism causing the pneumonia.
often mimics a common cold or the flu
For example, the patient may suddenly experience chills, shivering, high fever, sweating, chest pain (pleur­isy), and a dry and nonpro­ductive cough. Often what initially appears to be a cold or the flu, however, can in fact be a much more serious pulmonary infection
Anatomic Location of the Inflam­mation
patchy pattern of infection that is limited to the segmental bronchi and surrou­nding lung parenchyma
usually involves both lungs and is seen more often in the lower lobes of the lung
Lobar pneumonia
widespread or diffuse alveolar inflam­mation and consol­idation
typically the end result of a severe or long-term bronch­opn­eumonia in which the infection has spread from one lung segment to another until the entire lung lobe is involved
Inters­titial pneumonia
a diffuse and often bilateral inflam­mation that primarily involves the alveolar septa and inters­titial space
In contrast to alveolar pneumonia caused by bacteria, the polymo­rph­onu­clear leukocytes do not migrate into the alveol­i—they remain in the alveolar inters­titial spaces.
Mycoplasma pneumonia and other viruses cause inters­titial pneumo­nias.
most inters­titial pneumonias cause only minor permanent alveolar damage and usually resolve without conseq­uences
When both lungs are involved, the condition is sometimes called double pneumonia by layper­sons.
“Walking pneumonia”
used to describe a mild case of pneumonia
patients infected with Mycoplasma pneumoniae, who generally have mild symptoms and remain ambulatory
Because the distin­ction between lobar pneumonia and bronch­opn­eumonia can often be hazy, it is generally best to classify pneumonias either by the specific etiologic agent or, when no specific pathogen can be identi­fied, by the clinical setting in which
the pneumonia occurs; for example, hospit­al-­acq­uired pneumonia or commun­ity­-ac­quired pneumonia (CAP).

Risk Factors for Pneumonia

• Age over 65 years
• Aspiration of oropha­ryngeal secretions
• Viral respir­atory infections
• Chronic illness and debili­tation (e.g., diabetes mellitus, uremia)
• Chronic respir­atory disease (COPD, asthma, cystic fibrosis)
• Cancer (espec­ially lung cancer)
• Prolonged bed rest
• Trache­ostomy or endotr­acheal tube
• Abdominal or thoracic surgery
• Rib fractures
• Immuno­sup­pre­ssive therapy

Clinical Settings and Pathogens

Commun­ity­-Ac­quired Pneumonia
• Strept­ococcus pneumonia
Staphy­loc­occus aureus (also hospit­al-­acq­uired pneumonia)
Haemop­hilus influenza
Legionella pneumo­phila
• Entero­bac­ter­iaceae (Klebsiella pneumonia)
Pseudo­monas aeruginosa (also hospit­al-­acq­uired pneumonia)
Commun­ity­-Ac­quired Atypical Pneumonia
• Mycoplasma pneumonia
Chlamydia spp.—C. pneumonia, C. psittaci, C. tracho­matis, and C. burnetii (Q fever)
• Viruses: respir­atory syncytial virus, parain­fluenza virus (child­ren); influenza A and B (adults); adenovirus (military recruits), human metapn­eum­ovirus
Hospit­al-­Acq­uired Pneumonia (Nosoc­omial Pneumonia)
• Gram-n­egative bacilli belonging to Entero­bac­ter­iaceae (Klebsiella spp., Serratia marcescens, Escher­ichia coli) and Pseudo­monas spp., and Staphy­loc­occus aureus (usually methic­ill­in-­res­istant)
• Ventil­ato­r-a­cquired pneumonia (P. aeruginosa, Klebsiella, and S. aureus)
Aspiration Pneumonia
• Anaerobic oral flora (Bacte­roides, Prevot­ella, Fusoba­cte­rium, Peptos­tre­pto­coc­cus), admixed with aerobic bacteria (S. pneumonia, S. aureus, H. influenza, and Pseudo­monas aeruginosa)
Chronic Pneumonia
• Granul­oma­tous: Mycoba­cterium tuberc­ulosis and atypical mycoba­cteria, Histop­lasma capsulatum, Coccid­ioides immitis, Blasto­myces dermat­itidis
Candida albicans, Crypto­coccus neoformans, and Asperg­illus
• Nocardia
• Actino­myces
Necrot­izing Pneumonia and Lung Abscess
• Anaerobic bacteria (extremely common), with or without mixed aerobic infection S. areus, K. pneumonia, Strept­ococcus pyogenes, and type 3 pneumo­coccus (uncommon)
Pneumonia in the Immuno­com­pro­mised Host
• Cytome­gal­ovirus
Pneumo­cystis jirovecii
Mycoba­cterium avium complex (MAC)
• Invasive asperg­illosis
• Invasive candid­iasis
• “Usual” bacterial, viral, and fungal organisms (listed above)

Commun­ity­-Ac­quired Pneumonia (CAP)

a pneumonia acquired from normal social contact
Strept­ococcal pneumonia
"­Pne­umo­coccal pneumo­nia­"
Strept­ococcus pneumoniae (+)
accounts for more than 80% of all the bacterial pneumonias
gram-p­osi­tive, nonmotile coccus that is found singly, in pairs (called diplococci), and in short chains
cocci are enclosed in a smooth, thick polysa­cch­aride capsule that is essential for virulence
more than 80 different types of S. pneumoniae
Serotype 3 organisms are the most virulent.
transm­itted by aerosol from a cough or sneeze of an infected individual
Most strains of S. pneumoniae are sensitive to penicillin and its deriva­tives.
cultured from the sputum of patients having an acute exacer­bation of chronic bronchitis
Staphy­loc­occal pneumonia
two major groups of Staphy­loc­occus:
(1) Staphy­loc­occus aureus, which is respon­sible for most “staph” infections in humans
(2) Staphy­loc­occus albus and Staphy­loc­occus epider­midis, which are part of the normal skin flora
gram-p­ositive cocci found singly, in pairs (called diplococci), and in irregular clusters
Staphy­loc­occal pneumonia
often follows a predis­posing virus infection and is seen most often in children and immuno­sup­pressed adults
transm­itted by aerosol from a cough or sneeze of an infected individual and indirectly via contact with contam­inated floors, bedding, clothes, and the like
common cause of hospit­al-­acq­uired pneumonia or nosocomial pneumonia
becoming increa­singly antibiotic resist­ant­—thus the term multiple drug–r­esi­stant S. aureus (MDRSA) organisms
Haemop­hilus influenzae
Haemop­hilus influenzae
a common inhabitant of human pharyngeal flora
s one of the smallest gram-n­egative bacilli, measuring about 1.5 mm in length and 0.3 mm in width
It appears as coccob­acilli on Gram stain.
There are six types of H. influe­nzae, designated A to F
only type B is commonly pathogenic
transm­itted via aerosol or contact with contam­inated objects
sensitive to cold and does not survive long after expect­oration
y cultured from the sputum of patients having an acute exacer­bation of chronic bronchitis
Additional risk factors for H. influenzae infection include COPD, defects in B-cell function, functional and anatomic asplenia, and human immuno­def­iciency virus (HIV) infection.
H. influenzae type B
Pneumonia caused by H. influenzae type B is seen most often in children aged 1 month to 6 years old.
almost always the cause of acute epiglo­ttitis
Legionella pneumo­phila
In July 1976, a severe pneumo­nia­-like disease outbreak occurred at an American Legion convention in Philad­elphia.
an unusual and fastidious gram-n­egative bacillus with atypical concen­tra­tions of certain branch­ed-­chain lipids
More than 20 Legionella species have now been identified
Most of the species are free-l­iving in soil and water, where they act as decomposer organisms.
multiplies in standing water such as contam­inated mud puddles, large air-co­ndi­tioning systems, and water tanks
transm­itted when it becomes airborne and enters the patient’s lungs as an aerosol
No convincing evidence suggests that the organism is transm­itted from person to person
can be detected in pleural fluid, sputum, or lung tissue by direct fluore­scent antibody microscopy
rarely found outside the lungs, the organism may be found in other tissues
. The disease is most commonly seen in middle­-aged men who smoke
Entero­bac­ter­iaceae (Klebs­iella pneumonia)
Klebsiella pneumoniae
Friedl­änder’s Bacillus
have long been associated with lobar pneumonia, partic­ularly in men older than 40 years and in chronic alcoholics of both genders
a gram-n­egative bacillus that is found singly, in pairs, and in chains of varying lengths
normal inhabitant of the human gastro­int­estinal tract
can be transm­itted directly by aerosol or indirectly by contact with freshly contam­inated articles
a common nosoco­mial, or hospit­al-­acq­uired, disease
typically transm­itted by routes such as clothing, intrav­enous solutions, foods, and the hands of health­-care workers
mortality of patients with K. pneumoniae is very high because septicemia is a frequent compli­cation
Pseudo­monas aeruginosa
highly mobile, gram-n­egative bacillus
often found in the gastro­int­estinal tract, burns, and cathet­erized urinary tract and is a contam­inant in many aqueous solutions
frequently cultured from the respir­atory tract of patients who are chroni­cally ill and trache­ost­omized, and is a leading cause of hospit­al-­acq­uired pneumonia
a particular problem for the respir­atory therapist. Risk factors include neutro­penia, HIV infection, preexi­sting lung disease, endotr­acheal intuba­tion, and previous antibiotic use
thrives in dampness; it is often cultured from contam­inated respir­atory therapy equipment
transm­itted by aerosol or by direct contact with freshly contam­inated articles
very mucoid colonial form and the sputum is frequently green and sweet smelling

Commun­ity­-Ac­quired Atypical Pneumonia

The clinical presen­tation of the patient with commun­ity­-ac­quired atypical pneumonia is often subacute.
The patient typically presents with a variety of both pulmonary and extra-­pul­monary findings (e.g., respir­atory symptoms such as cough plus headache, general fatigue, or diarrhea).
Mycoplasma pneumonia
mycoplasma organism
most common cause of an acquired atypical pneumonia
tiny, cell wall–d­efi­cient organisms
smaller than bacteria but larger than viruses
The pneumonia caused by the mycopl­asmal organism is commonly described as a primary atypical pneumonia
The term atypical refers to the fact that
(1) the organism escapes identi­fic­ation by standard bacter­iologic tests
(2) there is generally only a moderate amount of sputum
(3) there is an absence of alveolar consol­idation
(4) there is only a moderate elevation of white cell count
(5) there is a lack of alveolar exudate
mycoplasma organism (cont)
causes symptoms similar to both bacterial and viral pneumonia, although the symptoms develop more gradually and are often milder
Chills and fever are early symptoms
patient typically presents with a mild fever, and patchy inflam­matory changes in the lungs that are mostly confined to the alveolar septa and pulmonary inters­titium
common symptom of mycoplasma pneumonia is a cough that tends to come in violent attacks, producing only a small amount of white mucus
Some patients experience nausea or vomiting
In some cases, the patients may experience a profound weakness that lasts for a long time.
Mycoplasma pneumonia is commonly seen among children and young adults.
spreads easily in areas where people congre­gate, such as child-care centers, schools, and homeless shelters
e “walking pneumonia” because the condition is mild and the patient is usually ambulatory
Chlamydia spp. pneumonia
Chlamydia pneumonia, Chlamydia psittaci, Chlamydia tracho­matis and Coxiella burnetii (Q fever) closely resemble the clinical manife­sta­tions of those caused by M. pneumoniae.
a type of bacteria that may be found in the cervix, urethra, rectum, throat, and respir­atory tract
also found in the feces of a variety of birds
The clinical manife­sta­tions of C. psittaci closely resemble those caused by M. pneumoniae.
50% of all pneumo­nias, and several are associated with a commun­ity­-ac­quired atypical pneumonia
Although most viruses attack the upper airways, some can produce pneumonia.
Most of these pneumonias are not life threat­ening and last only a short time.
tends to start with flulike signs and symptoms. The early symptoms are a dry (nonpr­odu­ctive) cough, headache, fever, muscle pain, and fatigue.
As the disease progre­sses, the patient may become short of breath, cough, and produce a small amount of clear or white sputum.
Viral pneumonia always carries the risk of develo­pment of a secondary bacterial pneumonia.
minute organisms not visible by ordinary light microscopy
parasitic and depend on nutrients inside cells for their metabolic and reprod­uctive needs
90% of acute upper respir­atory tract infections are caused by viruses
most common cause of pneumonia in young children, peaking between the ages of 2 and 3 years
By school age, M. pneumoniae become more prevalent
Common viruses associated with commun­ity­-ac­quired atypical pneumonia include respir­atory syncytial virus, parain­fluenza virus (child­ren); influenza A and B (adults); adenovirus (military recruits), and human metapn­eum­ovirus.
Respir­atory Syncytial Virus (RSV)
member of the paramy­xovirus group
Parain­flu­enza, mumps, and rubella viruses also belong to this group.
most often seen in children less than 12 months of age and in older adults with underlying heart or pulmonary disease
Almost all children will be infected with RSV by their second birthday.
infection is rarely fatal in infants
often goes unreco­gnized but may play an important role as a forerunner to bacterial infections
Early attempts to develop an RSV vaccine have been unsucc­essful.
transm­itted by aerosol and by direct contact with infected indivi­duals
most commonly seen in patients during the late fall, winter, or early spring months
Many times the virus is misdia­gnosed in older children, who are given antibi­otics that do not produce improv­ement.
Parain­fluenza viruses
related to mumps, rubella, and RSV
There are five types of parain­fluenza viruses: types 1, 2, 3, 4A, and 4B.
Types 1, 2, and 3 are the major causes of infections in humans.
Type 1 is considered a croup type of virus.
Types 2 and 3 are associated with severe infect­ions.
Although type 3 is seen in persons of all ages, it usually is seen in infants younger than 2 months of age; types 1 and 2 are seen most often in children between the ages of 6 months and 5 years.
Types 1 and 2 typically occur in the fall, whereas type 3 infection most often is seen in the late spring and summer.
transm­itted by aerosol droplets and by direct person­-to­-person contact
known for their ability to spread rapidly among members of the same family
Influenza viruses A and B
most common causes of viral respir­atory tract infections
In the United States, influenza A and B commonly occur in epidemics during the winter months.
Children, young adults, and older indivi­duals are most at risk.
transm­itted from person to person by aerosol droplets
Often the first sign of an epidemic is an increase in school absent­eeism.
survives well in conditions of low temper­atures and low humidity
found in horses, swine, and birds
incubation period of 1 to 3 days and usually cause upper respir­atory tract infections
Epidem­iol­ogists fear a pandemic of influenza, stating it is an issue of “when” and “where” rather than “if.” The recent epidemic of H1N1 (“swine flu”) is a case in point.
serotypes 4, 7, 14, and 21 cause viral infections and pneumonia in all age groups
Serotype 7 has been related to fatal cases of pneumonia in children.
transm­itted by aerosol
Pneumonia caused by adenov­iruses generally occurs during the fall, winter, and spring.
Human metapn­eum­ovirus (hMPV)
negative single­-st­randed RNA virus associated with a family of viruses that also includes respir­atory syncytial (RSV) virus and parain­fluenza virus
After the respir­atory RSV, hMPV is the second most common cause of lower respir­atory infections in young children.
In comparison to RSV, the hMPV tends to occur in older children and is less severe.
Most patients with hMPV infection have mild symptoms including cough, runny nose or nasal conges­tion, sore throat, and fever.
More severe cases demons­trate wheezing, difficulty breathing, hoarse­ness, cough, and pneumonia.

Hospit­al-­Acq­uired Pneumonia

Nosocomial pneumonia
• an infection whose develo­pment is caused by the hospital enviro­nment
• Common causes of hospit­al-­acq­uired pneumonias include Entero­bac­ter­iaceae (Klebsiella spp., Serratia marcescens, Escher­ichia coli), Pseudo­monas spp., and Staphy­loc­occus aureus (usually methic­ill­in-­res­ist­ant).
Ventil­ato­r-a­cquired pneumonia (VAP)
ventil­ato­r-a­sso­ciated pneumonia
a pneumonia that develops more than 48 to 72 hours after endotr­acheal intubation
Common ventil­ato­r-a­sso­ciated infections include P. aeruginosa, Entero­bacter, Klebsiella, and S. aureus
Concern that the occurrence of VAP is preven­table lies as the root of possible reimbu­rsement penalties for hospitals in which it occurs.

Aspiration Pneumonia

Common pathogenic agents associated with aspiration pneumonia include anaerobic oral flora (Bacter­oides, Prevotella, Fusoba­cterium, Peptos­tre­pto­coccus), admixed with aerobic bacteria such as S. pneumonia, S. aureus, H. influenza, and P. aeruginosa.
Aspiration of gastric fluid with a pH of 2.5 or less causes a serious and often fatal form of pneumonia.
Aspiration of oropha­ryngeal secretions and gastric fluids are the major causes of anaerobic lung infect­ions.
Aspiration pneumo­nitis is commonly missed because acute inflam­matory reactions may not begin until several hours after aspiration of the gastric fluid.
The inflam­matory reaction generally increases in severity for 12 to 26 hours and may progress to acute respir­atory distress syndrome (ARDS), which includes inters­titial and intraa­lveolar edema, intraa­lveolar hyaline membrane formation, and atelec­tasis.
In the absence of a secondary bacterial infection, the inflam­mation usually becomes clinically insign­ificant in approx­imately 72 hours.
In 1946, Mendelson first described the clinical manife­sta­tions of tachyc­ardia, dyspnea, and cyanosis associated with the aspiration of acid stomach contents.
The clinical picture he described is now known as Mendel­son’s syndrome and is usually confined to aspiration pneumo­nitis in pregnant women
Aspiration pneumonia
broadly defined as the pulmonary result of the entry of material from the stomach or upper respir­atory tract into the lower airways
three distin­ctive forms of aspiration pneumonia, classified according to the nature of the aspirate, the clinical presen­tation, and management guidelines, as follows:
1. Toxic injury to the lung (such as that caused by gastric acid)
2. Obstru­ction (by foreign body or fluids)
3. Infection
the presumed cause of nearly all cases of anaerobic pulmonary infections
Studies suggest that anaerobic bacteria are the most common causative agents of lung abscesses; they are also commonly isolated in cases of empyema.
There is a difference between the aspiration of gastric contents and the aspiration of food. Aspiration of gastric contents causes initial hypoxemia regardless of the pH level of the aspirate.
Conseq­uently, oximetry is a good measur­ement if aspiration is suspected.
If the pH of the aspirate is relatively high (greater than 5.9), the initial injury is rapidly revers­ible. Such aspiration occurs in patients who receive antacids or proton pump inhibitors (PPIs).
If the pH is low (pH of unbuffered gastric contents normally ranges from 1 to 1.5), parenc­hymal damage may occur, with inflam­mation, edema, and hemorr­hage.
When food is aspirated, oblite­rative bronch­iolitis with subsequent granuloma formation occurs.
Gastro­eso­phageal reflux disease (GERD)
regurg­itation of stomach contents into the esophagus
causes disruption in nerve-­med­iated reflexes in the distal esophagus, resulting in alteration of the primary and secondary perist­altic wave and reflux
Therefore “to-an­d-fro” perist­alsis can result from spasticity at the distal esophageal sphincter and retrop­ulsion of middle and upper esophageal contents.
This may result in aspira­tion, although not necess­arily.
three times more prevalent in patients with asthma than in other patients
a frequently unreco­gnized cause of asthma
Presum­ably, acid reflux into the esophagus causes vagal stimul­ation, resulting in a reflexive increase in bronchial tone in patients with asthma.
Recent literature suggests that asympt­omatic reflux does not contribute to worsening lung function, although it and chronic sinusitis are the two most unreco­gnized causes of chronic cough. GERD causes chronic cough in 10% to 20% of patients.
Normal swallowing mechanics has four phases, as follows:
1. Oral prepar­atory
2. Oral
3. Pharyngeal
4. Esophageal
The first two phases are considered voluntary stages (cereb­ral). These phases occur as the food or liquid is prepared for entry to the pharynx and esophagus. The airway is open while food is prepared in the oral cavity. Adequate tongue function is important for the manipu­lation and propulsion of the prepared food or liquid (called a bolus) into the pharynx. Spillage of liquid into the pharynx during the chewing of food is usually not a problem in patients with good airway protec­tion.
The pharyngeal phase (invol­untary brain stem function) of swallowing involves numerous physio­logic actions that direct the bolus into the esophagus:
• Elevation and retraction of the veloph­ary­ngeal port (velum closure)
• Pharyngeal muscle contra­ction
• Elevation and forward excursion of the larynx (epigl­ottic closure)
• Closure of the laryngeal vestibule, false vocal folds, and true vocal folds (laryngeal closure)
• Relaxation of the upper esophageal sphincter (UES)
Airway closure progresses inferiorly to superiorly in the larynx as the food bolus is directed laterally around the airway and into the esophagus.
Respir­ation is halted during the pharyngeal phase for an approx­imately 1-second apneic period, although duration varies with bolus volume and viscosity.
Bolus transit in the esophageal phase (under both brain stem and intrinsic neural control) lasts 8 to 20 seconds.
In this phase, the UES relaxes to receive the bolus with a perist­altic wave from the pharyngeal superior constr­ictor muscles, forcing the bolus through the relaxed UES.
The primary perist­alsis propels the bolus through the esophagus and lower esophageal sphincter and into the stomach.
Six cranial nerves carry motor signals generated by cerebral and brain stem swallowing centers:
• V (trige­minal)
• VII (facial)
• IX (gloss­oph­ary­ngeal)
• X (vagus)
• XI (spinal accessory [minor involv­ement])
• XI (spinal accessory [minor involv­ement])
The relati­onship between respir­ation and swallowing is not random.
Expiration before and after the pharyngeal phase in normal swallowing is believed to serve as an inherent closure and clearance mechanism against penetr­ation of food or liquids into the airway entrance.
result of an abnormal swallow that can involve the oral, pharyn­geal, and esophageal phases
Penetr­ation into the laryngeal vestibule occurs when food or liquid (or both) enters the larynx but does not pass through the vocal cords into the trachea.
Aspiration is the passage of food or liquid into the trachea via the vocal cords.
Diagnostic tests for dysphagia include the modified barium swallow (MBS), video-­flu­oro­scopy, video-­fib­eroptic endoscopy, and the modified Evan’s blue dye tests.
The Evan’s blue dye test involves instilling a deep blue dye into the gastro­int­estinal tract and seeing if it can be suctioned from the trachea. If it can, it suggests a commun­ication between the two struct­ures, such as a fistula.
The MBS and video-­flu­oro­scopy tests are most definitive for identi­fic­ation of the particular phase of the swallow that is dysfun­cti­onal.
The modified Evan’s blue dye test can be unreliable (as much as 40% of the time) as a test suggesting aspiration in a patient who is trache­ost­omized.
Both false-­pos­itive and false-­neg­ative test results occur
A compro­mised respir­atory system can cause dysphagia and, conver­sely, dysphagia may cause respir­atory compli­cat­ions. COPD can result in a slowed oral and pharyngeal transit time, reduced coordi­nation and strength of the oral and pharyngeal muscul­ature, and reduced airway clearance by coughing.
Treatment of dysphagia is specific to the nature of the disorder.
Varied methods of presen­tation of foods and liquids, bolus volumes and consis­tency, postural movements, and food temper­ature can affect the dynamics of the relation between respir­ation and swallo­wing.
Large volumes of liquid requiring uninte­rrupted swallowing result in longer apneic periods and can be difficult for patients with shortness of breath and dyspnea.
Small-­volume bites and swallows make sense in this setting.
Unilateral cerebr­ova­scular accidents (strokes) and hemorrhage tend to cause hypoph­ary­ngeal hemipa­resis.
Difficulty in swallowing (with impairment of the oral phase) and aspiration of thin fluids therefore may follow.
The facial and tongue weakness can result in poor bolus control in the oral cavity.
Silent aspiration
aspiration that does not evoke clinically observable adverse symptoms such as overt coughing, choking, and immediate respir­atory distress
Some patients have silent aspiration after a stroke.
Evidence also suggests that some sequelae of stroke include laryng­oph­ary­ngeal sensory deficits with no subjective or objective evidence of dysphagia, such as choking, gagging, or cough.
Some patients with severe and bilateral sensory deficits develop aspiration pneumonia.
The clinical findings of dysphonia, dysarthria, abnormal gag reflex, abnormal volitional cough, cough after swallow, and voice change after swallow all signif­icantly relate to aspiration and are predictors of silent aspira­tion.
Conver­sely, a normal reflex cough after a stroke indicates an intact laryngeal cough reflex, a protected airway, and low risk for developing aspiration pneumonia with oral feeding.
The cough reflex is signif­icantly reduced in older patients.
Patients with a trache­ostomy are at high risk for silent aspira­tion.
Perhaps 55% to 70% of intubated or trache­ostomy patients aspirate.
A trache­ostomy tube has a direct effect on the pharyngeal phase of a swallow because of the alteration of normal respir­atory function (exhal­ation timing) as well as the anatomic alteration and the physical resistance imposed by the trache­ostomy tube itself.
Normal laryngeal elevation is reduced, partic­ularly with the cuff inflated, which leads to inadequate airway closure and increased pharyngeal residue.
Poor sensory response to material entering the larynx contri­butes to the slowing of an uncoor­dinated laryngeal closure.
The protective cough may be lessened because of the impaired laryngeal sensation. Subglottic air pressure (coord­inated exhalation with swallow) helps prevent entry of material into the trachea and is reduced in patients with a trache­ostomy. An inflated cuffed trache­ostomy can cause compli­cations that can anchor the larynx to the anterior wall of the neck and desens­itize the pharynx. Delayed triggering of the swallowing response and increased pharyngeal residue are prevalent.
Recomm­end­ations for oral feeding include consid­era­tions of dietary consis­tency, specif­ically defined for solids and liquids; skilled superv­ision with oral intake; safe swallowing strate­gies; positi­oning requir­ements; cuff deflation; and tracheal occlusion issues. It may be necessary to coordinate mealtime with ventilator weaning attempts to optimize more positive pressure generation to aid in expelling laryngeal residue and creating subglottic pressure.
The dynamic changes a patient may experience clinically necess­itate a coordi­nated team approach, including physical, occupa­tional, and respir­atory therap­ists; a speech­-la­nguage pathol­ogist; registered dietitian; and nurse.
This approach allows for effective management of trache­ostomy and non-tr­ach­eostomy patients and avoidance of aspiration

Chronic Pneumonia

A localized lesion in patients with a normal immune system, with or without regional lymph node involv­ement.
Patients with chronic pneumonia usually have granul­omatous inflam­mation, which is often due to bacteria (e.g., M. tuberc­ulosis) or fungi.
In patients whose immune system is compro­mised, the dissem­ination of the causative organism throughout the body is the usual presen­tation.
Tuberc­ulosis is by far the most important organism within the category of chronic pneumo­nias.
The World Health Organi­zation (WHO) estimates that tuberc­ulosis causes 6% of all deaths worldwide, making it the most common cause of death resulting from a single infectious agent.
Chronic pneumonias associated with granulomas include tuberc­ulosis and fungal diseases of the lung.
an infectious disease caused by Mycoba­cterium tuberc­ulosis.
M. tuberc­ulosis is a slender, rod-shaped aerobic organism.
Predis­posing factors of tuberc­ulosis include homele­ssness, drug abuse, and acquired immuno­def­iciency syndrome (AIDS).
The initial response of the lung is an inflam­matory reaction that is similar to any acute pneumonia.
Because most fungi are aerobes, the lung is a prime site for fungal infect­ions.
Primary fungal pathogens include Histop­lasma capsulatum, Coccid­ioides immitis, and Blasto­myces dermat­itidis.
In addition, the opport­unistic yeast pathogens Candida albicans, Crypto­coccus neoformans, and Asperg­illus may also cause pneumonia in certain patients.
C. albicans
occurs as normal flora in the oral cavity, genitalia, and large intestine
rarely seen in the trache­obr­onchial tree or lung parenchyma
In patients with AIDS, however, C. albicans commonly causes an infection of the mouth, pharynx, esophagus, vagina, skin, and lungs.
A C. albicans infection of the mouth is called thrush; it is charac­terized by a white, adherent, patchy infection of the membranes of the mouth, gums, cheeks, and throat.
C. neoformans
prolif­erates in pigeon droppings, which have a high nitrogen content, and readily scatters into the air and dust
Today, the highest rate of crypto­coc­cosis occurs among patients with AIDS and persons undergoing steroid therapy.
The molds of the genus Asperg­illus may be the most pervasive of all fungi—­esp­ecially Asperg­illus fumigatus.
found in soil, vegeta­tion, leaf detritus, food, and compost heaps
Persons who breathe the air of granaries, barns, and silos are at the greatest risk.
Asperg­illus infection usually occurs in the lungs.
almost always an opport­unistic infection and lately has posed a serious threat to patients with AIDS
When fungal organisms are inhaled, the initial response of the lung is an inflam­matory reaction similar to that produced by any acute pneumonia.
gram-p­osi­tive, rod-shaped bacteria that can be found worldwide in soils that are rich with organic matter
It has a total of 85 species.
also found in healthy gingiva and period­ontal pockets
Most Nocardia infections occur as an opport­unistic infection in patients with weak immune systems, such as small children, the elderly, and the immuno­com­pro­mised (most common in patients with HIV).
normally present in the gingival area and are common opport­unistic pathogens of humans, partic­ularly in the oral cavity (e.g., infections associated with dental procedures and oral abscesses)
In rare cases, these bacteria can cause actino­mycosis, a disease charac­terized by the formation of abscesses in the mouth, lungs, or the gastro­int­estinal tract.

Necrot­izing Pneumonia and Lung Abscess

Cytome­gal­ovirus (CMV)
a member of the herpes­virus family, is the most common viral pulmonary compli­cation of AIDS
CMV infection commonly coexists with Pneumo­cystis carinii infection.
Pneumo­cystis jirovecii
also known as Pneumo­cystis carinii
an opport­uni­stic, often fatal, form of pneumonia seen in patients who are profoundly immuno­sup­pressed
Although the Pneumo­cystis organism has been identified as a protozoan, recent inform­ation suggests that it is more closely related to fungi.
can normally be found in the lungs of humans, but it does not cause disease in healthy hosts, only in indivi­duals whose immune systems are critically impaired
Pneumo­cystis pneumonia
the major pulmonary infection seen in patients with AIDS and HIV infection
In vulnerable hosts the disease spreads rapidly throughout the lungs.
Before AIDS, P. carinii pneumonia was seen primarily in patients with malign­ancy, in organ transplant recipi­ents, and in patients with diseases requiring treatment with large doses of immuno­sup­pre­ssive agents.
Today, most cases of P. carinii pneumonia are seen in patients with AIDS.
The early clinical manife­sta­tions of Pneumo­cystis in patients with AIDS are indist­ing­uis­hable from those of any other pneumonia.
Signs and Symptoms
include progre­ssive exertional dyspnea, a dry cough that may or may not produce mucoid sputum, difficulty in taking a deep breath (not caused by pleurisy), and fever with or without sweats.
The therapist may hear normal breath sounds on auscul­tation or end-in­spi­ratory crackles.
The chest x-ray film may be normal at first; later it will show bilateral inters­titial infilt­rates, which may progress to alveolar filling and “white out” of the chest x-ray film.
Mycoba­cterium avium complex (MAC)
a serious opport­unistic infection that is caused by the following two similar bacteria: Mycoba­cterium avium and Mycoba­cterium interc­ell­ulare
found in the soil and dust particles
MAC is commonly found in patients with AIDS.
The mode of infection is usually inhalation or ingestion.
can spread through the bloods­tream to infect lymph nodes, bone marrow, the liver, the spleen, spinal fluid, the lungs, and the intestinal tract
Typical symptoms of MAC include fever, night sweats, weight loss, fatigue, anemia, diarrhea, and enlarged spleen.
Invasive Asperg­illosis
general term used for a wide variety of infections caused by the fungi of the genus Asperg­illus
The most common forms are allergic bronch­opu­lmonary asperg­illosis, pulmonary asperg­illoma, and invasive asperg­illosis.
Most humans inhale Asperg­illus spores every day
However, in indivi­duals who are immuno­com­pro­mised, an asperg­illosis pneumonia often develops.
Invasive Candid­iasis
general term describing fungal infections caused by a variety of species of the genus Candida, most often by Candida albicans, a yeastlike fungus
These fungi are normally found in the mouth, vagina, and intestines of healthy indivi­duals.
Under normal circum­sta­nces, the normal bacteria in these areas keep the amount of Candida species in balance.
However, in patients with a weakened immune system (such as people with HIV/AIDS), the fungi can invade tissue that normally would be resistant to infect­ion­—thus, producing an opport­unistic infection.
Candida infections can involve any part of the body
In some cases, the fungus enters the bloods­tream and causes invasive disease affecting internal body organs such as the kidneys, spleen, lungs, liver, eyes, meninges, brain, and heart valves.
Other Causes
small, pleomo­rphic coccob­acilli
Most ricket­tsiae are intrac­ellular parasites possessing both ribonu­cleic acid (RNA) and deoxyr­ibo­nucleic acid (DNA).
There are several pathogenic members of the Rickettsia family: Rickettsia rickettsii (Rocky Mountain spotted fever), Rickettsia akari (ricke­tts­ial­pox), Rickettsia prowazekii (typhus), and Rickettsia burnetii, also called Coxiella burnetii (Q fever).
All species of the genus Rickettsia are unstable outside of cells except for R. burnetii (Q fever), which is extremely resistant to heat and light.
Q fever can cause pneumonia as well as a prolonged febrile illness, an influe­nza­-like illness, and endoca­rditis.
The organism is commonly transm­itted by arthropods (lice, fleas, ticks, mites). It may also be transm­itted by cattle, sheep, and goats and possibly in raw milk.
Varicella (Chick­enpox)
varicella virus
usually causes a benign disease in children aged 2 to 8 years, and compli­cations of varicella are not common
In some cases, however, varicella has been noted to spread to the lungs and cause a serious secondary pneumo­nitis.
The mortality rate of varicella pneumonia is about 20%.
Rubella (Measles)
Measles virus spreads from person to person by the respir­atory route.
Respir­atory compli­cations are often encoun­tered in measles because of the widespread involv­ement of the mucosa of the respir­atory tract (e.g., excessive bronchial secretions and infect­ion).
Severe Acute Respir­atory Syndrome
In 2002, China reported the first case of severe acute respir­atory syndrome (SARS).
Shortly after this report, the disease was documented in numerous countries, including Vietnam, Singapore, and Indonesia. Both the United States and Canada have reported imported cases.
Health officials believe that the cause of SARS is a newly recognized virus strain called a corona­virus.
Other viruses, however, are still under invest­igation as potential causes.
Corona­viruses are a group of viruses that have a halolike or corona­-like appear­ance when observed under an electron micros­cope.
Known forms of corona­virus cause common colds and upper respir­atory tract infect­ions.
SARS is highly contagious on close personal contact with infected indivi­duals.
It spreads through droplet transm­ission by coughing and sneezing.
SARS might be transm­itted through the air or from objects that have become contam­inated.
The incubation period for SARS is typically 2 to 7 days
Initially, the patient usually develops a fever (>100.4 °F or >38.0 °C), followed by chills, headaches, general feeling of discom­fort, and body aches.
Toward the end of the incubation period, the patient with SARS usually develops a dry, nonpro­ductive cough, shortness of breath, and malaise.
In severe causes hypoxemia develops.
According to the Centers for Disease Control and Prevention (CDC), 10% to 20% of patients with SARS require mechanical ventil­ation.
In spite of this fact, death from SARS is rare.
No specific treatment recomm­end­ations exist at this time.
The CDC, however, recommends that patients with SARS receive the same treatment used for any patient with serious commun­ity­-ac­quired atypical pneumonia of unknown cause
Lipoid Pneumo­nitis
The aspiration of mineral oil, used medically as a lubricant, has also been known to cause pneumo­nit­is–­lipoid pneumo­nitis.
The severity of the pneumonia depends on the type of oil aspirated.
Oils from animal fats cause the most serious reaction, whereas oils of vegetable origin are relatively inert.
When mineral oil is inhaled in an aeroso­lized form, an intense pulmonary tissue reaction occurs.
Avian Influenza A
(also called bird flu and H5N1)
a subtype of the A strain virus and is highly contagious in birds.
Histor­ically, bird flu has not been known to infect humans.
However, in Hong Kong in 1997 the first avian influenza virus to infect humans directly was reported.
This outbreak was linked to chickens and classified as avian influenza A (H5N1).
Since the Hong Kong outbreak, the bird flu virus has been reported in parts of Europe, Turkey, Romania, the Near East, and Africa.
Many of the infected people have died.
Experts are concerned that if the avian flu virus continues to spread, a worldwide pandemic outbreak could occur.
People with bird flu may develop life-t­hre­atening compli­ca­tio­ns,such as viral pneumonia and ARDS (the most common cause of bird flu–re­lated deaths).

General Management of Pneumonia

treatment of pneumonia is based on
(1) the specific cause of the pneumonia, and
(2) the severity of symptoms demons­trated by the patient
For bacterial pneumonia
first line of defense is usually an antibiotic prescribed by the attending physician
Although there are a few viral pneumonias that may be treated with antiviral medica­tions, the recomm­ended treatment is usually the same as for the flu—bed rest and plenty of fluids.
In addition, over-t­he-­counter medica­tions are often helpful to reduce fever, treat aches and pains, and depress the dry cough associated with pneumonia.
In severe pneumonia, hospit­ali­zation may be required.

Respir­atory Care Treatment Protocols

Oxygen Therapy Protocol
used to treat hypoxemia, decrease the work of breathing, and decrease myocardial work
Because of the hypoxemia associated with pneumonia, supple­mental oxygen may be required.
The hypoxemia that develops in pneumonia is most commonly caused by alveolar consol­idation and capillary shunting associated with the disorder.
Hypoxemia caused by capillary shunting is at least partially refractory to oxygen therapy.
Lung Expansion Therapy Protocol
Lung expansion therapy may be admini­stered to attempt to offset the atelec­tasis associated with some pneumo­nias, but its effects are not consis­tently good.
Diagnostic and therap­eut­ically, thorac­entesis may be used if a pleural effusion is present
From a diagnostic standp­oint, fluid samples may be examined for the following:
• Color
• Odor
• RBC count
• Protein
• Glucose
• Lactic dehydr­ogenase (LDH)
• Amylase
• pH
• Wright’s, Gram, and acid-fast bacillus (AFB) stains
• Aerobic, anaerobic, tuberc­ulosis, and fungal cultures
• Cytology
Therap­eutic thorac­entesis may be used to encourage lung reexpa­nsion when atelec­tasis is part of the clinical prese


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