1. clinical presentation and diagnosis of ventilator-associated pneumonia

23.7.2014 Clinical presentation and diagnosis of ventilator-associated pneumonia

http://www.uptodate.com/contents/clinical-presentation-and-diagnosis-of-ventilator-associated-pneumonia?topicKey=PULM%2F1635&elapsedTimeMs=3& 1/13

Official reprint from UpToDate www.uptodate.com 2014 UpToDate

AuthorMarin H Kollef, MD

Section EditorsPolly E Parsons, MDJohn G Bartlett, MD

Deputy EditorGeraldine Finlay, MD

Clinical presentation and diagnosis of ventilator-associated pneumonia

All topics are updated as new evidence becomes available and our peer review process is complete.Literature review current through: Jun 2014. | This topic last updated: Mar 19, 2014.

INTRODUCTION Ventilator-associated pneumonia (VAP) is a type of hospital-acquired (ie, nosocomial)

pneumonia that develops after more than 48 hours of mechanical ventilation. It is a common and serious

problem, with an estimated incidence of 10 to 25 percent and an all-cause mortality of 25 to 50 percent [1,2].

Early diagnosis is important because prompt, appropriate treatment can be lifesaving.

The clinical presentation and diagnosis of VAP are reviewed here. The risk factors for VAP and its prevention

and treatment are discussed separately. (See "Treatment of hospital-acquired, ventilator-associated, and

healthcare-associated pneumonia in adults" and "Risk factors and prevention of hospital-acquired, ventilator-

associated, and healthcare-associated pneumonia in adults" and "The ventilator circuit and ventilator-associated

pneumonia".).

CLINICAL FEATURES

Presentation VAP typically presents with a new or progressive pulmonary infiltrate and one or more of the

following findings: fever, purulent tracheobronchial secretions, leukocytosis, increased respiratory rate,

decreased tidal volume, increased minute ventilation, and decreased oxygenation [3]. These symptoms and

signs may develop gradually or suddenly.

Medical history Patients with VAP are typically unable to provide any history because they are either

sedated or their ability to communicate is impaired by the endotracheal or tracheostomy tube. Those few

patients who are able to convey symptoms are likely to report dyspnea or chest congestion.

Physical examination Fever and an increased volume of purulent tracheobronchial secretions are common

among patients with VAP. On auscultation, patients typically have diffuse, asymmetric rhonchi due to the

tracheobronchial secretions that the patient is unable to mobilize. The rhonchi are often accompanied by focal

findings, such as crackles and decreased breath sounds. In addition, many patients are tachypneic with

increased respiratory effort. Bronchospasm (wheezing and increased expiratory time) and hemoptysis are also

common. These pulmonary signs may be accompanied by systemic abnormalities, such as encephalopathy or

sepsis. (See "Sepsis and the systemic inflammatory response syndrome: Definitions, epidemiology, and

prognosis", section on 'Sepsis'.)

Ventilator performance Deterioration in the patients respiratory performance, as identified during routine

assessment of the mechanical ventilator, may be the initial sign of VAP. This includes an increased respiratory

rate, decreased tidal volume, increased minute ventilation, or decreased oxygenation. Many patients will require

more ventilatory support or inspired oxygen than they did previously.

DIAGNOSTIC EVALUATION Diagnostic evaluation is required any time that VAP is suspected because

clinical features alone are nonspecific [4-6]. The goal is to confirm VAP and to identify the likely pathogen, so

that the appropriate treatment can be initiated. The evaluation begins with a chest radiograph. Patients who have

an abnormal chest radiograph should have their respiratory tract sampled and specimens sent for microscopic

analysis and culture.

These steps are ideally performed prior to the initiation of antibiotic therapy because antibiotic therapy reduces

the sensitivity of both the microscopic analysis and culture [7,8] (similarly, these steps are ideally performed

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prior to changing the antibiotic regimen of patients suspected of developing VAP while receiving antibiotics

[9,10]). Once the respiratory specimens have been obtained, empiric antibiotic therapy is indicated for all cases

of suspected VAP, unless the clinical suspicion is low and the microscopic analysis of lower respiratory tract

samples is negative (ie, few neutrophils). Occasionally, the severity of illness or delays in sampling requires that

empiric antibiotic therapy be initiated prior to diagnostic sampling. (See "Treatment of hospital-acquired,

ventilator-associated, and healthcare-associated pneumonia in adults", section on 'Empiric treatment'.)

Chest imaging A chest radiograph should be performed on all patients with suspected VAP [1]. A normal

chest radiograph excludes VAP, while an abnormal radiograph should prompt the collection of respiratory tract

secretions. Common radiographic abnormalities in VAP include alveolar infiltrates, air bronchograms, and

silhouetting of adjacent solid organs.

While an abnormal chest radiograph is required to diagnose VAP, it is not sufficient. The reason that

radiographic abnormalities alone are insufficient to diagnose VAP is that they are nonspecific (ie, they frequently

exist in the absence of VAP) [1,4,11,12]. This was illustrated by an observational study in which only 43 percent

of patients who had clinical and radiographic evidence of VAP at the time of their death were subsequently

confirmed to have VAP by postmortem examination [12].

Additional benefits of the chest radiograph are that it can help determine the severity of the disease (multilobar

versus unilobar) and identify complications, such as pleural effusions or cavitation.

Respiratory sampling Lower respiratory tract sampling is indicated for all patients who are suspected of

having VAP and have an abnormal chest radiograph [1]. There are a variety of methods available to sample

material from the airways and alveoli, including nonbronchoscopic (ie, blind) and bronchoscopic techniques.

Nonbronchoscopic lower respiratory tract sampling includes tracheobronchial aspiration or mini-BAL [13-21]:

A clinician is not necessary to perform or supervise nonbronchoscopic sampling. This reduces the cost, allows

specimens to be obtained quickly, and facilitates serial sampling when necessary.

Bronchoscopic sampling is performed using either bronchoalveolar lavage (BAL) or a protected specimen brush

(PSB) (see "Flexible bronchoscopy: Indications and contraindications" and "Flexible bronchoscopy: Equipment,

procedure, and complications"):

Bronchoscopic sampling and nonbronchoscopic sampling have been compared in the setting of suspected VAP

[22-26]. The evidence indicates that bronchoscopic sampling does not improve mortality, length of hospital stay,

duration of mechanical ventilation, or length of intensive care unit stay [22,24,26,27]. However, it minimizes

airway contamination of the alveolar samples and provides an accurate assessment of the alveolar cell

population. Bronchoscopic sampling may lead to a narrower antimicrobial regimen and more rapid de-escalation

of antimicrobial therapy [22,23,25,28], which presumably reduces antibiotic resistance.

The decision about whether to perform nonbronchoscopic or bronchoscopic sampling ultimately depends upon a

case-by-case determination of the benefits of a narrow antibiotic regimen versus the risks of bronchoscopy. In

patients for whom the risk of bronchoscopy is low, we frequently perform bronchoscopic BAL [29].

Tracheobronchial aspiration is performed by advancing a catheter through the endotracheal tube until

resistance is met and then applying suction.

Mini-BAL is performed by advancing a catheter through the endotracheal tube until resistance is met,

infusing sterile saline through the catheter, and then aspirating.

BAL involves the infusion and aspiration of sterile saline through a flexible bronchoscope that is wedged in

a bronchial segmental orifice. The technique of BAL is discussed in detail separately. (See "Basic

principles and technique of bronchoalveolar lavage".)

A PSB is a brush that is contained within a protective sheath. It is designed to minimize the likelihood that

the brush will be contaminated during bronchoscopy. The procedure involves placing the bronchoscope tip

next to a bronchial segmental orifice, pushing the sheath through the bronchoscope, and then advancing

the brush out of the sheath and into the airway. Specimens are collected by brushing the airway wall,

withdrawing the brush into the sheath, and then removing the sheath from the bronchoscope.

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Microscopic analysis The lower respiratory specimens should be sent for microscopic analysis. The most

common microscopic analysis is the Gram stain. It can be used to semi-quantitate polymorphonuclear

leukocytes and other cell types, as well as to characterize the morphology of bacteria. The presence of

abundant neutrophils is consistent with VAP and the bacterial morphology may suggest a likely pathogen.

Gram stain analysis may decrease the incidence of inappropriate antimicrobial therapy and improve diagnostic

accuracy when correlated with culture results [1].

A differential cell count can also be performed by microscopic analysis following a BAL. It determines the

proportion of total nucleated cells in the spun sediment of BAL fluid that are neutrophils, lymphocytes,

macrophages, eosinophils, basophils, or other nucleated cells. In a prospective cohort study of 39 patients,

VAP was correctly excluded in all patients in whom neutrophils were fewer than 50 percent of the total

nucleated cells [30].

Respiratory culture The lower respiratory specimens should also be sent for culture. Quantitative or

semiquantitative cultures are both acceptable, with the choice depending largely upon availability.

Quantitative culture Quantitative cultures can be performed on bronchoscopic or nonbronchoscopic

specimens. VAP is supported when an established threshold of bacterial growth is exceeded. Only bacteria that

are pulmonary pathogens should be counted. As examples, Staphylococcus epidermidis, enterococci, and

most gram positive bacilli (except actinomycosis and nocardia) should not be counted.

Thresholds of 1,000,000 colony forming units (cfu)/mL for samples obtained by tracheobronchial aspiration,

10,000 cfu/mL for samples obtained by BAL, or 1000 cfu/mL for samples obtained by PSB are most accurate

because they are sufficiently high that patients with tracheobronchial colonization are unlikely to be mistaken for

patients with VAP [1,9,31]. Lower thresholds are reasonable if the risk of a missing a VAP (ie, a false-negative

result) exceeds the risk of unnecessary treatment (ie, a false-positive result) [32]. According to a prospective

cohort study of 122 patients, thresholds between 1000 and 10,000 cfu/mL for BAL specimens and between 100

and 1000 cfu/mL for PSB specimens decrease the likelihood of a false-negative result to a greater degree than

they increase the likelihood of a false-positive result [33].

Generally speaking, quantitative cultures derived from nonbronchoscopic specimens tend to have a lower

specificity than quantitative cultures derived from bronchoscopic specimens [15,17]. However, this is balanced

by a higher sensitivity, resulting in comparable diagnostic accuracy. In a prospective cohort study of 38

patients, the accuracy of quantitative cultures was greatest when the sample was obtained by tracheobronchial

aspiration, followed (in order of decreasing accuracy) by BAL, mini-BAL, and PSB [15].

Quantitative cultures do not appear to improve clinical outcomes, compared with semiquantitative cultures. This

was illustrated by a meta-analysis of three randomized trials (1240 patients), which found that quantitative

cultures did not alter mortality, days of mechanical ventilation, or length of ICU stay, compared with

semiquantitative cultures [27]. Despite the lack of improvement in clinical outcomes, many clinicians believe

that quantitative cultures are advantageous because they may lead to more judicious use of antibiotics [29].

Semiquantitative culture Semiquantitative cultures can also be performed on bronchoscopic or

nonbronchoscopic samples. They are typically reported as showing heavy, moderate, light, or no growth [1]. The

amount of growth that suggests VAP has not been firmly established, but it is reasonable to consider a

semiquantitative culture with moderate or heavy growth to be positive. Compared with quantitative cultures,

semiquantitative cultures are less likely to distinguish patients whose airways are colonized from those who

have VAP [1]. As a result, false-positive results are more likely, which can lead to inappropriate therapy.

Other diagnostic tests Procalcitonin, the clinical pulmonary infection score, and lung biopsy are additional

diagnostic tests that are often discussed; however, they have little role in the evaluation of suspected VAP.

Biological markers Biologic markers are sometimes used to try to distinguish between bacterial and

non-bacterial causes of pneumonia.

Procalcitonin is a promising biologic marker. The use of serum procalcitonin to facilitate the decision about

whether or not to initiate antibiotics in patients admitted with suspected community-acquired pneumonia

was evaluated in several randomized trials that found that serum procalcitonin decreased antibiotic

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DIAGNOSTIC CRITERIA The diagnosis of VAP is made when a patient who has been mechanically

ventilated for 48 hours develops a new or progressive infiltrate and the respiratory specimens are positive (ie,

increased neutrophils are seen in the microscopic analysis and growth of a pathogen in culture exceeds a

predefined threshold).

VAP cannot be confirmed or excluded until the culture results are complete, which generally takes two to three

days. At that time, the patient should be reevaluated to determine if additional diagnostic evaluation or changes

in management are warranted. These decisions are based upon the culture results and response to empiric

therapy (algorithm 1):

Antimicrobial therapy for VAP is discussed separately. (See "Treatment of hospital-acquired, ventilator-

associated, and healthcare-associated pneumonia in adults".)

DIFFERENTIAL DIAGNOSIS There are many causes of pulmonary infiltrates, fever, respiratory

exposure without affecting clinical outcomes [34-36]. In suspected VAP, however, it is unknown if serum

procalcitonin levels are a useful guide for the decision about whether to initiate antibiotics because the

evidence is conflicting [37,38]. Until higher quality studies resolve the uncertainty, we believe that serum

procalcitonin levels should not be used for this purpose. However, there are two situations in which

procalcitonin may be useful in patients with confirmed VAP. First, procalcitonin may be helpful in the

decision of whether to discontinue antibiotic therapy [39]. Second, procalcitonin may be a useful

prognostic marker, since progressive increases in serum procalcitonin have been associated with septic

shock and mortality [40-42].

Other biomarkers, such as C-reactive protein (CRP) and soluble triggering receptor expressed on myeloid

cells-1 (sTREM-1), were initially considered promising markers for improving diagnostic strategies for VAP.

However, more recent studies suggest that the measurement of such biomarkers in BAL fluid has minimal

diagnostic value for VAP [43-45].

Clinical Pulmonary Infection Score (CPIS) The CPIS combines clinical, radiographic, physiologic, and

microbiologic data into a numerical result (table 1). Initial validation of the CPIS found that a score greater

than six correlated with VAP [46]. However, subsequent studies failed to confirm this. In one prospective

cohort study, the CPIS identified VAP with a sensitivity and specificity of only 60 and 59 percent,

respectively [47].

Lung biopsy Histologic examination of lung tissue obtained by biopsy is an imperfect and seldom used

method of diagnosing VAP. In addition to requiring an invasive procedure, its reliability and reproducibility

are uncertain. This is probably due to a lack of standardized histologic criteria to define VAP. In a

prospective cohort study, 39 patients who died while receiving mechanical ventilation underwent post

mortem open lung biopsy [48]. The histology was reviewed separately by four pathologists who reported a

prevalence of VAP ranging from 18 to 38 percent. One pathologist reinterpreted the histology six months

later and reclassified the VAP status of two patients.

Laboratory tests Patients with VAP usually develop leukocytosis with a neutrophil predominance.

However, there are no laboratory findings that are specific for VAP.

Patients with negative cultures who have not improved may not have VAP; therefore, other diagnoses or

sites of infection should be sought.

Patients with negative cultures who have improved may not have VAP; antimicrobial therapy should be

discontinued.

Patients with positive cultures who have not improved probably have VAP, but they may be receiving

inappropriate antimicrobial therapy, have a complication of the VAP (eg, abscess, empyema), have a

second source of infection, or have a second diagnosis. The antimicrobial regimen should be adjusted and

then potential causes for failing to improve clinically should be sought.

Patients with positive cultures who have improved probably have VAP, which has responded to

antimicrobial therapy; the antimicrobial therapy should be narrowed according to the culture results.

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abnormalities, and leukocytosis other than VAP. The following conditions can present with this constellation of

findings:

VENTILATOR ASSOCIATED EVENTS The CDC National Healthcare Safety Network implemented ventilator-

associated events (VAE) surveillance in January 2013 [49]. This is a three-tier surveillance definition algorithm.

This algorithm uses objective, readily available data elements to identify a broad range of conditions and

Aspiration pneumonitis Aspiration pneumonitis refers to chemical aspiration without infection; it is

distinguished from VAP by history (ie, witnessed aspiration), microscopic analysis and culture of

respiratory secretions (ie, negative), and clinical course (ie, self-limited). (See "Aspiration pneumonia in

adults".)

Pulmonary embolism with infarction Pulmonary embolism can mimic VAP if it causes pulmonary

infarction; it is distinguished from VAP when computed tomography pulmonary angiography (CT-PA),

ventilation-perfusion (V/Q) scanning, or conventional pulmonary angiography reveals pulmonary embolism.

(See "Diagnosis of acute pulmonary embolism".)

Acute respiratory distress syndrome Acute respiratory distress syndrome (ARDS) is characterized by

an acute onset of bilateral pulmonary infiltrates and severe hypoxemia in the absence of an elevated left

atrial pressure; it is distinguished from VAP by history (ie, risk factors for ARDS may be present) and the

microscopic analysis and culture of respiratory secretions (ie, negative). (See "Acute respiratory distress

syndrome: Clinical features and diagnosis in adults".)

Pulmonary hemorrhage Both pulmonary hemorrhage and VAP may cause hemoptysis in addition to the

constellation of findings described above. Pulmonary hemorrhage tends to present with frank bleeding

while VAP often appears as blood mixed with purulent secretions, but this distinction is imperfect.

Definitively distinguishing pulmonary hemorrhage from VAP requires that the cause of the hemoptysis be

identified. (See "Etiology and evaluation of hemoptysis in adults".)

Lung contusion Pulmonary contusion is due to trauma, but it may be difficult to distinguish from VAP

because the clinical and radiographic manifestations are similar and often delayed following the trauma.

Pulmonary contusion is distinguished from VAP by history (ie, recent trauma) and the microscopic

analysis and culture of respiratory secretions (ie, negative). (See "Overview of inpatient management in the

adult trauma patient", section on 'Pulmonary contusion'.)

Infiltrative tumor The lung is a common site of primary or metastatic cancer and the manifestations of a

diffuse infiltrative cancer are similar to VAP. Diffuse infiltrative cancer is distinguished from VAP by history

(ie, history of malignancy), as well as both culture (ie, negative) and microscopic analysis (ie, negative for

neutrophils and bacteria, but positive for malignant cells) of respiratory secretions.

Radiation pneumonitis Radiation-induced lung injury may cause acute pneumonitis or chronic fibrosis.

The former develops approximately four to twelve weeks after irradiation, with symptoms and signs that

mimic VAP; it is distinguished from VAP by history (ie, prior irradiation) and the microscopic analysis and

culture of respiratory secretions (ie, negative). (See "Radiation-induced lung injury".)

Drug reaction Pulmonary drug toxicity can result from many different drugs, most notably antineoplastic

agents (eg, cyclophosphamide, methotrexate). The clinical manifestations of pulmonary drug toxicity can

be identical to VAP and the timing of the onset of symptoms and signs is highly variable (ie, days to

months after receiving the medication). Pulmonary drug toxicity is distinguished from VAP by history (ie,

received a potentially toxic agent within the past months) and the microscopic analysis and culture of

respiratory secretions (ie, negative). (See "Pulmonary toxicity associated with systemic antineoplastic

therapy: Clinical presentation, diagnosis, and treatment".)

Cryptogenic organizing pneumonia Cryptogenic organizing pneumonia (COP) is an idiopathic form of

organizing pneumonia. Its clinical features may be identical to VAP; it is distinguished from VAP by

history (ie, risk factors for COP may be present, such as a recent viral infection) and the microscopic

analysis and culture of respiratory secretions (ie, negative). Definitive diagnosis of COP requires lung

biopsy. (See "Cryptogenic organizing pneumonia".)

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complications occurring in mechanically ventilated adult patients. These include, but are not limited to VAP. The

first tier definition, ventilator-associated condition (VAC), identifies patients with a period of sustained respiratory

deterioration following a sustained period of stability or improvement on the ventilator (changes in PEEP or

FiO ). The second tier definition, infection-related ventilator-associated complication (IVAC), requires that

patients with VAC also have an abnormal temperature or white blood cell count, and be started on a new

antimicrobial agent. The third tier definitions, possible and probable VAP, require that patients with IVAC also

have laboratory and/or microbiological evidence of respiratory infection [50]. The effect of implementing this

surveillance system and of VAP bundles on the prevention of VACs is unknown.

SUMMARY AND RECOMMENDATIONS

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REFERENCES

1. American Thoracic Society, Infectious Diseases Society of America. Guidelines for the management ofadults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J RespirCrit Care Med 2005; 171:388.

2. Chastre J, Fagon JY. Ventilator-associated pneumonia. Am J Respir Crit Care Med 2002; 165:867.

3. Meduri GU. Diagnosis and differential diagnosis of ventilator-associated pneumonia. Clin Chest Med 1995;16:61.

4. Andrews CP, Coalson JJ, Smith JD, Johanson WG Jr. Diagnosis of nosocomial bacterial pneumonia inacute, diffuse lung injury. Chest 1981; 80:254.

5. Fagon JY, Chastre J, Hance AJ, et al. Detection of nosocomial lung infection in ventilated patients. Use ofa protected specimen brush and quantitative culture techniques in 147 patients. Am Rev Respir Dis 1988;

2

Ventilator-associated pneumonia (VAP) is a type of hospital-acquired (ie, nosocomial) pneumonia that

develops after more than 48 hours of mechanical ventilation. (See 'Introduction' above.)

VAP typically presents with the gradual or sudden onset of a new or progressive pulmonary infiltrate and

one or more of the following findings: fever, purulent tracheobronchial secretions, leukocytosis, increased

respiratory rate, decreased tidal volume, increased minute ventilation, and decreased oxygenation. (See

'Clinical features' above.)

A diagnostic evaluation is required whenever VAP is suspected because clinical features alone are

nonspecific. The goal of the diagnostic evaluation is to confirm VAP and identify the likely pathogen. A

typical evaluation begins with a chest radiograph. For patients with an abnormal chest radiograph, the

respiratory tract is sampled and the specimens are sent for microscopic analysis and culture. (See

'Diagnostic evaluation' above.)

These steps are ideally performed prior to the initiation of antibiotic therapy because antibiotic therapy

reduces the sensitivity of both the microscopic analysis and culture (similarly, these steps are ideally

performed prior to changing the antibiotic regimen of patients suspected of developing VAP while receiving

antibiotics). Once the respiratory specimens have been obtained, empiric antibiotic therapy is indicated for

all cases of suspected VAP, unless the clinical suspicion is low and the microscopic analysis of lower

respiratory tract samples is negative (ie, few neutrophils). Occasionally, the severity of illness or delays in

sampling requires that empiric antibiotic therapy be initiated prior to diagnostic sampling. (See 'Diagnostic

evaluation' above.)

The diagnosis of VAP is made when a patient who has been mechanically ventilated for at least 48 hours

develops a new or progressive pulmonary infiltrate and cultures of the respiratory specimens are positive

(ie, increased neutrophils are seen in the microscopic analysis and growth of a pathogen in culture

exceeds a predefined threshold). (See 'Diagnostic criteria' above.)

There are many causes of pulmonary infiltrates, fever, respiratory abnormalities, and leukocytosis other

than VAP. These include aspiration pneumonitis, pulmonary embolism with infarction, acute respiratory

distress syndrome, pulmonary hemorrhage, pulmonary contusion, infiltrative tumor, radiation pneumonitis,

pulmonary drug toxicity, and cryptogenic organizing pneumonia. (See 'Differential diagnosis' above.)

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GRAPHICS

Clinical Pulmonary Infection Score (CPIS)

Temperature

36.5 or 38.4 = 0 point

38.5 or 38.9 = 1 point

39 or 240 or ARDS (defined as PaO /FIO 200, PAWP 18 mmHg and

acute bilateral infiltrates) = 0 points

PaO /FIO 240 and no ARDS = 2 points

Pulmonary radiography

No infiltrate = 0 point

Diffuse (patchy) infiltrate = 1 point

Localized infiltrate = 2 points

Progression of pulmonary infiltrate

No radiographic progression = 0 point

Radiographic progression (after HF and ARDS excluded) = 2 points

Culture of tracheal aspirate

Pathogenic bacteria cultured in rare or few quantities or no growth = 0 point

Pathogenic bacteria cultured in moderate or heavy quantity = 1 point

Same pathogenic bacteria seen on Gram stain, add 1 point

Total (a score of >6 was considered suggestive of pneumonia)

An initial score is based upon the first five variables. The last two variables are assessed

on day 2 or 3.

ARDS: acute respiratory distress syndrome; HF: heart failure; PAWP: pulmonary arterial wedge

pressure.

Adapted with permission from: Singh N, Rogers P, Atwood CW, et al. Short-course empiric antibiotic

therapy for patients with pulmonary infiltrates in the intensive care unit: a proposed solution for

indiscriminate antibiotic prescription. Am J Respir Crit Care Med 2000; 162:505. Copyright 2002

American Thoracic Society.

2 2 2 2

2 2



Graphic 77054 Version 4.0



Diagnostic algorithm for hospital-acquired, ventilator

associated pneumonia

WBC: white blood cell.

Reproduced with permission from: American Thoracic Society and the Infectious

Diseases Society of America. Guidelines for the management of adults with hospital-

acquired, ventilator associated, and healthcare-associated pneumonia. Am J Respir Crit

Care Med 2005; 171:388. Copyright 2002 American Thoracic Society.

Graphic 76508 Version 2.0



Disclosures: Marin H Kollef, MD Nothing to disclose. Polly E Parsons, MD Nothing to disclose. John G Bartlett, MD Nothing todisclose. Geraldine Finlay, MD Employee of UpToDate, Inc.

Contributor disclosures are review ed for conflicts of interest by the editorial group. When found, these are addressed by vettingthrough a multi-level review process, and through requirements for references to be provided to support the content. Appropriatelyreferenced content is required of all authors and must conform to UpToDate standards of evidence.

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