SLP26 2011 Dysphagia and the respiratory system

J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Dysphagia and the respiratory system: Aerodigestive tract primer
2012 KSHA Convention
Kansas City, 09/2011
James L. Coyle, Ph.D., CCC‐SLP, BRS‐S
Department of Communication Science and Disorders
University of Pittsburgh [jcoyle@pitt.edu]
Pre‐test
• 1. Breathing is driven by the need for oxygen.
• 2. Dysphagia is the cause of aspiration pneumonia
• 3. Hospitalized patients never get sick in the hospital
• 4. Feeding tubes prevent aspiration. True or false?
• 5. Thin liquid aspirators aspirate less with thick liquids.
• 6. Thick liquids reduce pneumonia in thin liquid aspirators.
• 7. Eliminating dysphagia is the best way to reduce aspiration pneumonia risk. True or False?
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Dysphagia & pneumonia
Disease
Dysphagia
Pneumonia
Exposure
Pneumonia
Dysphagia
Risk Factors
Pneumonia
?
Dysphagia
3
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J. Coyle, Ph.D., KSHA 2011‐1
Dysphagia
8/22/2011
?
Pneumonia
4
Medical SLP
• Role of Modern Medical SLP
– What is the nature of the patient’s dysphagia?
– How likely is current disease related to dysphagia?
– What is risk of future disease due to dysphagia?
– Can that risk be lowered?
– How?
– What if the plan cannot work??
5
Our patients
People diagnosed with pneumonia
People with pneumonia
People who aspirate
People with dysphagia
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
People diagnosed with pneumonia
People diagnosed with pneumonia, but DO NOT have pneumonia
People who actually have pneumonia
Pneumonia, and diagnosed
People with pneumonia whom are never diagnosed
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Dysphagia, no aspiration
People who aspirate
Aspirate and have dysphagia
People with dysphagia
Aspirate, but not due to dysphagia
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People diagnosed with pneumonia
Pneumonia diagnosis,
do not aspirate
People who aspirate
Aspirate,
diagnosed with
pneumonia
Aspirate, no pneumonia diagnosis
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
• Sounds simple?
10
This one is easy
All 4
X
People diagnosed with pneumonia
X
People who actually have pneumonia
X
People who aspirate
X
People with dysphagia
More difficult
How about this one?
This one looks easy,
especially if patient
appears dysphagic
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Pneumonia dilemmas
• Aspiration is the main risk factor
– And nobody is thinking about it
• Dysphagia‐related, or otherwise
• Aspiration may be one problem
– But other risk factors are present, or
• Aspiration is not the problem
– Other things mimic pneumonia
– But aspiration is presumed to be the problem
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Respiratory System Functions
• Ventilation – Transfer of oxygen rich air into lungs
– Transfer of oxygen depleted/waste air out of lungs
• Respiration
– Transfer of oxygen to circulatory system, then to working organs
– Removal of some metabolic waste from working organs, via circulatory system
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Ventilation
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Biomechanics of Ventilation
• Pressure driven “pumping” system
– Movement of air from environment into lungs
– Inspiration is ALWAYS active
– Expiration largely passive (rest)
• Ventilation needs
– Alveolar compliance
– Intact “pump” mechanism
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Factors Enabling Ventilation
• Alveolar Compliance created by:
– Delicate, thin, stretchable tissue
– Surfactant
• Reduces alveolar surface tension
– Chest wall coupling
• Holds lungs partially open
• Respiratory pump intact
– Innervated diaphragm
– Room to expand
16
Factors DISabling Ventilation
• Alveolar Compliance damaged:
– Thickened, damaged alveoli
• Fibrosis, inflammation
– Loss of Surfactant
• ARDS, pneumonitis
– Damaged chest wall coupling
• Atelectasis, pneumothorax
• Damaged respiratory pump
– Kyphosis, scoliosis, paralysis, pain
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Ventilatory Disorders‐restrictive
• Others:
– Atelectasis – Pleural effusion
– Pneumothorax
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Ventilatory Disorders‐restrictive
• How they mimic pneumonia
– Rapid respiratory rate
• More breaths/minute to increase ventilation
• Caused by dysphagia?
– Overwhelmingly, no. Exceptions:
• Severe, recurrent pneumonia/abscess 
– pneumothorax, exudative pleural effusion
• Chronic aspiration and pulmonary fibrosis
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Respiration
20
Terminal Respiratory Structures
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Factors enabling respiration
• Delicate thin membranes intact
– Gas diffusion
• Respiratory membrane unobstructed
• Enough alveolar surface area – Meets demands for gas exchange
• Open airways
– Delivery of gases into and out
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Factors DISabling respiration
 Thickening of respiratory membrane
 Obstruction of respiratory membrane
 Blocked airways, or pulmonary infiltrates
 Loss of alveolar surface area
 ALL:  CO2 cant get out of blood; O2 can’t get into blood
 INCREASED RESPIRATORY RATE 23
Respiratory Disease
• Chronic obstructive pulmonary disease
– Chronic bronchitis
– Emphysema • Acute obstructive pulmonary disease
– Pulmonary edema
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Respiratory Disorders‐obstructive
• Mimic pneumonia
– Rapid respiratory rate, CO2 retention, hypoxemia
• Caused by dysphagia?
– Overwhelmingly, no. Exceptions:
• Chronic aspiration  alveolar destruction (COPD)
• Aspiration  airway obstruction
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Pulmonary Edema (CHF)‐acute + obstructive
• Pulmonary Edema
– Alveoli filled with serum, other seeping fluids from capillaries
– Heart failure
• Pulmonary hypertension
– Increased capillary permeability
• pneumonitis
Dysphagia related? No, unless inflammation caused by prandial aspiration-caused infection.
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Iatrogenic causes of respiratory conditions
• Iatrogenic condition: a disease cause by treatment of another disease
– Sedation (restrictive)
• CNS depression
– Disruption of pleural linkage (restrictive)
• Cardiothoracic surgery
– Phrenic nerve injury (restrictive)
• Cardiothoracic surgery
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Breathing and Swallowing
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Breathing and Swallowing
• In Normals...
– Exhale  Swallow  Exhale; Young and Old1
– Respiratory rate (young) is about 16/min.2
– “ “ (elderly) “ “ 20/min.
– Total Swallow Duration, Swallow Apnea Duration3
• Increase with age
• Decrease with lower lung volumes
1.
2.
3.
Perlman et al., 2005; Hiss et al., 2002; Leslie et al., 2002; Shaker et al., 1992. Leslie et al., 2002;
Gross et al., 2003; Hiss et al., 2003; Leslie et al., 2005.
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Normal Respiratory Rate
Total Swallow Duration=1.5 – 2.5 seconds
inspiration
Swallow apnea
1.5 – 2.5 seconds
Seconds 
expiration
Respiratory Rate = 16/min
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Abnormal Breathe‐Swallow Phase
inspiration
Swallow apnea
1.5 – 2.5 seconds
Seconds 
expiration
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Rapid Respiratory Rate
Total Swallow Duration=1.5 – 2.5 seconds
inspiration
Swallow apnea
1.5 – 2.5 seconds
Seconds 
expiration
Respiratory Rate = 36/min
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TYPES OF PNEUMONIA AND DIFFERENTIAL DIAGNOSIS OF ASPIRATION PNEUMONIA 33
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Lung response to aspiration
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Aspiration
• Solid or liquid matter
– Not airborne, inhaled pathogen
• Courses by gravity, to its destination
• Crosses plane of true vocal folds
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Aspiration‐destination
• Entrance of liquid or solid matter into the respiratory system, below the vocal folds
– Not airborne
• Aspirated material is gravity dependent
•
Airborne is not R
L
R
L
36
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Aspiration: water
Inside alveolus
H2O
H2O
H2O
Water
H2O
Respiratory
Membrane
Alveolar membrane
Capillary membrane
RBC’s
Toward (L) heart
From (R) heart
Plasma containing water inside capillary
WBC’s
Effros, et al., 2000
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Aspiration:hypertonic solution
Inside alveolus
Hypertonic solution
Respiratory
Membrane
Alveolar membrane
Capillary membrane
RBC’s
From (R) heart
H2O
H2O
H2O
H2O
Toward (L) heart
Plasma containing water inside capillary
WBC’s
38
Aspiration: Chemical or other irritants (pathogens)
infiltrate
Inside alveolus
Chemical irritant
Respiratory
Membrane
Alveolar membrane
Capillary membrane
RBC’s
From (R) heart
H2O
H2O
plasma
H2O
Toward (L) heart
Plasma containing water Inside capillary
WBC’s
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Acute Respiratory Distress Syndrome (ARDS)
Normal acute resolution
Ware & Matthay, 2000
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Pneumonia
Pathogen + Impaired Host Resistance + Other Risk Factors Pneumonia
Infection + Inflammation
Nosocomial
Pneumonia
CAP
Aspirated
Pathogen
Inhaled Pathogen
Inhaled Pathogen
Aspiration
Pneumonia
Typical
VAP
Atypical
DAP
Non‐
DAP
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Aspiration Pneumonia
• Aspirated pathogen
– In solid or liquid matter
– Courses by gravity, to its destination
– Not airborne, inhaled pathogen
• Enters airway
– Dysphagia
– emesis
– gastroesophageal  esophagopharyngeal reflux
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Non‐aspiration pneumonia
• Inhaled, airborne pathogen
– Environmental pathogens
– Bacterial, viral
• Hematogenous pathogen
– Septicemia
• Direct inoculation
– Contaminated respiratory circuit/equipment
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Pneumonia
•
•
•
•
•
Most frequent infectious cause of death*
40% higher incidence in elderly / over 14** 13%‐48% of all Nursing Home Infections
#2 nosocomial infection (UTI) in hospitals***
High case fatality rate
– 55% (elderly)
– Leading cause of mortality in children under 5****
Marston, et al., 1997*; National Center for Health Statistics, 2003**; ***Niederman, et al., 2002;
****Baine et al., 2001; Almirall, et al., 2000
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What is Pneumonia?
O2
O2
CO2
O2
CO2
O2
CO2
O2
O2
CO2
Capillary – RBC, WBC
O2
45
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
What is Pneumonia?
O2
O2
CO2
O2
O2
CO2
O2
O2
O2
CO2
CO2
Capillary – RBC, WBC
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O2
CO2
O2
O2
O2
O2
CO2
O2
CO2
O2
CO2
capillary
47
What is Pneumonia?
O2
O2
O2
CO2
O2
CO2
O2
CO2
CO2
O2
O2
capillary
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Aspiration Pneumonitis
• Non‐Infectious‐chemical trauma
– Acute Lung Injury: caustic or particulate aspiration
– Inflammation of alveoli by effects of irritants
• No primary infection
– Can develop opportunistic infection
• Inflammatory edema reduces surface area
• Gastric contents
– Sterile, acidic, caustic
– Damage to airways, alveoli
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O2
CO2
O2
O2
O2
O2
O2
CO2
CO2
O2
O2
O2
O2
O2
CO2
O2
CO2
O2
CO2
CO2
O2
O2
CO2
CO2
CO2
capillary
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Differential Diagnosis‐ clinical, laboratory signs
• Aspiration pneumonia
–
–
–
–
–
–
–
–
Inflammation
Cough – productive
Bronchospasm Dyspnea
Hypoxemia Purulent sputum Tachypnea Malaise
• Aspiration pneumonitis
–
–
–
–
–
–
–
–
Inflammation
Cough ‐ not productive
Bronchospasm
Dyspnea Hypoxemia Frothy or bloody sputum
Tachypnea
Respiratory distress
minutes to hours after aspiration; may persist
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Differential Diagnosis
• Dysphagia‐related Aspiration Pneumonia (DAP)
– Infiltrates in dependent segments
– Patient has DYSPHAGIA!
– Other evidence of infection
• Non‐dysphagia related aspiration pneumonia
– No dysphagia; GE reflux, emesis…
• Acid suppression therapy?
– Exposure to patients with CAP
– Other risk factors (next)
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Aspiration Related Infiltrates
(R) Basilar infiltrates
(R) Upper lobe infiltrates
Aspiration produces pneumonitis or pneumonia in gravity dependent portions of lung(s).
“Dependence” depends on posture when aspiration occurs, density & volume aspirated.
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Right lung
Right Left
Posterior Anterior
RUL, RML, RLL, LLL
54
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Left lung
Right Left
Anterior Posterior
LUL, LLL
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Differential Diagnosis
• Laboratory Values
– WBC
• Immunocompromise?
• Radiographic evidence
– New infiltrate
• Fever‐persistent
• Respiratory distress
– Productive cough
• First 3 do not subside:
– Pneumonia is likely
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Risk factors for aspiration pneumonia
• Is dysphagia all that matters?
– Some things to think about
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Oral biofilm development
Oral biofilm
Oral anaerobes
Variety of microorganisms in dental plaque
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http://bioinfo.bact.wisc.edu/themicrobialworld/streptococci_biofilm.jpg; Public health image library #3074, Centers for Disease Control
A new source of AP?
• Aggressive acid suppression may create conditions favoring pathogenesis of pneumonia*
– PPI: twofold increase in pneumonia
• Ambulatory and hospitalized patients
– H2 blockers: increased risk (<2)
• GE reflux and pulmonary fibrosis
*Marik, 2001; Marik and Zaloga, 2002; Laheij, et al., 2004; Eurich, 2010; Herzig et al., 2009 59
GOSP
• Geriatric Oral Science Project
– Langmore, et al., 1998. Predictors of aspiration pneumonia: how important is dysphagia? Dysphagia 13: 69‐81.
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
GOSP
• N = 189 adults, age 60‐95
– 160: COPD, CHF, DM, CVA, other neuro, GI disease
• 112 had more than one of these, 48 had only one
– 29 patients had none of these (control group)
– Excluded
• Head/neck CA, current pneumonia, new CHF
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GOSP
• All patients underwent:
– Clinical Swallow Exam*
– VFSS**
– 3 nuclear medicine esophageal studies
• Clearance, GE reflux, aspiration of refluxate
– Dental exam*
– Saliva collection* and culture; throat culture
– Interview, medical and functional status (chart)
* repeated annually; ** repeated if suspected change in swallow function
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GOSP
• Dependent variables (outcome of interest)
– Pneumonia
•
•
•
•
Panel consensus 3 physician (geri., card., pulm.)
WBC > 12,000
Fever > 38C
New infiltrate on CXR (higher weight)
– Death
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
GOSP
Independent variables
 Living site

Home, NH, Acute care
 Medical diagnosis
 Dental/oral status





Dentate, edentulous, # decayed teeth, disease
Currently smoking
Mental status
Activity level
Dependency for oral care


Dependency for feeding
VFSS observations







Biomechanics, aspiration
Esophageal function
Tube feeding status/use
Oral cleanliness
Toothbrushing frequency
Flossing frequency
Oral hygiene frequency

Professional 64
Results (risk factors)
• 41/189 patients developed pneumonia (22%)
– NH: 44%, Acute care: 19%; Home: 9%
– Diagnosis
•
•
•
•
CVA: 27%
Other neuro: 33%
COPD or CHF or GI: 32%
COPD and GI: 49%
– Currently smoking: 32%
65
Results (risk factors)
• Medications (average # per patient)
– Pneumonia: >10, others: 7.6
• Dysphagia on VFSS: 81%
– 58% pneumonia patients aspirate liquids
– 27% aspirated food
– 50% aspirated secretions
• Tube feeding: 27% patients with pneumonia
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Analysis 1 ‐ Association
• Risk factors (I.V.’)s
–
–
–
–
–
–
–
–
• Dependent variables
Variable 1
Variable 2
Variable 3
Variable 4
Variable 5
Variable 6
Dysphagia
Variable 7
Pneumonia
67
Significant predictors
Pneumonia
No pneumonia
Dysphagia
81%
47%
Tube feeding at pneumonia dx
27%
9%
Low or no activity
59%
28%
Dependent oral care
34%
10%
Dependent feeding
41%
6%
Brush teeth occasionally or never
40%
12%
# decayed teeth
5.2
2.4
Dry or excess oral
secretions
38%
17%
But, EACH WAS SIGNIFICANT IN PRESENCE OF OTHER RISK FACTORS
68
Analysis 2 ‐ Predictive Value
• Risk factors (I.V.’s)
–
–
–
–
–
–
–
–
Variable 1
Variable 2
Variable 3
Variable 4
Variable 5
Variable 6
Dysphagia
Variable 7
• Dependent variables
Pneumonia
ODDS RATIO
“How much does each risk factor, independently increase pneumonia risk?”
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Independent predictors (OR)
Increased likelihood of pneumonia, when patient has the risk factor All patients
Patients eating orally
Dentate patients
Dentate patients eating orally
Dependent for feeding
‐
19.98
ns
11.8
Multiple Diagnoses
ns
ns
4.9
7.3
Now smoking
ns
4.1
ns
ns
Tube fed before pneumonia
3.0
‐
ns
‐
Dependent for oral care
2.8
ns
ns
ns
# decayed teeth
‐
‐
1.2
ns
Number of meds
ns
1.16
ns
ns
Dysphagia/
Aspiration
ns
ns
ns
ns
70
• Dysphagia/Aspiration
– Was not an independent risk factor
– Only significant in presence of other risk factors
– ASPIRATION ALONE IS NOT ENOUGH TO CAUSE PNEUMONIA
• Mitigating other risk factors in dysphagic
patients, lowers pneumonia risk more than efforts to mitigate dysphagia.
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Summary
• There are many clues pointing to, or away from, a diagnosis of DAP
• There are mimics of DAP
• Aspiration can occur without dysphagia
• Aspiration is one potential source of pneumonia pathogens
• All respiratory illnesses are NOT dysphagia related
• ALL PNEUMONIAS ARE NOT ASPIRATION RELATED
• Patient appearance with pneumonia is NOT baseline
• History, course, physical signs are data for the SLP
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J. Coyle, Ph.D., KSHA 2011‐1
8/22/2011
Questions
• Thank you
jcoyle@pitt.edu
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Thank you.
jcoyle@pitt.edu
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