c. lee - asthma presentation 10 · peak expiratory flow rate (peak flow) useful indicator of...
TRANSCRIPT
10/6/2014
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Tommy’s Story: An Overview of Asthma Mangement
Clifton C. Lee, MD, FAAP, FHM
Associate Professor of Pediatrics
Chief, Pediatric Hospital Medicine
Children’s Hospital of Richmond at VCU
Disclosure
Obviously, I have no financial disclosures
However, I can tell you…..
Objectives for this talk….
Overview of asthma management
Monitoring of symptoms and lung function
Patient education
Controlling triggers factors and comorbid conditions
Pharmacologic therapy
Emergency department management
Discuss various pharmacologic agents used in acute management
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This is Tommy!
This is also Tommy….
Goals of Asthma Treatment
Reduce impairment
Reduce risk
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Reduce Impairment
Freedom from frequent asthma symptoms
Minimal need (≤2 days per week) of inhaled SABAs
Few nighttime awakenings (≤2 nights per month)
Optimization of lung function
Maintenance of normal daily activities
Asthma care satisfaction
Reduce Risk
Prevent recurrent exacerbations and need for ED or inpatient care
Prevent reduce lung growth in child and loss of lung function in adults
Optimization of pharmacotherapy with minimal or no adverse effects
Monitoring Patients with Asthma
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Symptom Assessment
Assessment of impairment
Has your asthma awakened you at night or in the early morning?
How often have you been needing to use your relief medication to relieve symptoms of cough, shortness of breath, or chest tightness?
Have you needed any unscheduled care for your asthma?
Have you been able to participate in school/work and recreational activities?
If you are measuring your peak flow, has it been lower than your personal best?
Have you had any side effects from your asthma medications?
Symptom Assessment
Assessment of risk
Have you taken oral steroids for your asthma in the past year?
Have you been hospitalized for your asthma? If yes, how many times have you been hospitalized in the past year?
Have you been admitted to the intensive care unit or been intubated because of your asthma?
Do you currently smoke cigarettes or exposed to tobacco smoke?
Monitoring Pulmonary Function
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Peak Expiratory Flow Rate (Peak Flow)
Useful indicator of airflow obstruction
Repeated measurements are useful
May not be accurate for first time users
Home monitoring is helpful with patients with moderate to severe asthma
Periodic checks on the use of the peak flow meter
Normal range: 80‐100% of “personal best” value
Patient Education
Patient Education
Enable patients/parents to become active partners
Effectiveness of direct one‐on‐one education
Decreases hospitalizations
Improves daily function
Improves patient/parent satisfaction
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Pharmacologic Treatment
Categories of Asthma Severity
Intermittent
Mild persistent
Moderate persistent
Severe persistent
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Intermittent Mild persistent Moderate persistent
Severe persistent
Symptoms ≤2 days/week >2 days/week but not daily
Daily Throughout the day
Nighttime awakenings
≤2 times/month
3‐4 times/month >1 time/week but not nightly
Often 7 times/week
SABA use for symptomcontrol
≤2 days/week >2 days/week but not daily
Daily Several times per day
Interferencewith normal activity
None Minor limitation Some limitation Extremely limited
Lung function
• FEV₁ >80% predicted
• FEV₁/FVC >85%
• FEV₁ up to 80% predicted
• FEV₁/FVC >80%
• FEV₁ 60‐79% predicted
• FEV₁/FVC 75‐80%
• FEV₁ <60% predicted
• FEV₁/FVC <75%
How about Tommy?
Wheezes 3 days/week
Awakens with coughing 4 times/month
Uses albuterol MDI 3 times/week
Very little limitation with football practice
Intermittent Mild persistent Moderate persistent
Severe persistent
Symptoms ≤2 days/week >2 days/week but not daily
Daily Throughout the day
Nighttime awakenings
≤2 times/month
3‐4 times/month >1 time/week but not nightly
Often 7 times/week
SABA use for symptomcontrol
≤2 days/week >2 days/week but not daily
Daily Several times per day
Interferencewith normal activity
None Minor limitation Some limitation Extremely limited
Lung function
• FEV₁ >80% predicted
• FEV₁/FVC >85%
• FEV₁ up to 80% predicted
• FEV₁/FVC >80%
• FEV₁ 60‐79% predicted
• FEV₁/FVC 75‐80%
• FEV₁ <60% predicted
• FEV₁/FVC <75%
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Back to Tommy….
His only medication is albuterol MDI PRN (usually before practice and games)
Recently his asthma symptoms have been more noticeable
Only been hospitalized once (not PICU or intubations)
Last ED visit was 6 months ago and received steroids but none since
Should his medication regimen change?
Should Tommy see a Specialist?
When to refer
Experienced life‐threatening asthma exacerbation
Required hospitalization or more than 2 bursts of oral steroids/year
Child >5 years requires step 4 care or higher
Child <5 requires step 3 care of higher
Asthma not controlled after 3‐6 months of active therapy
Unresponsive to therapy
Uncertain diagnosis of asthma
Management complication (nasal polyps, chronic sinusitis, allergic rhinitis)
Additional diagnostic tests are needed (skin testing, bronchoscopy, PFTs)
Candidate for allergen immunotherapy (allergy shots)
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Tommy is going to the ED!!
Case Presentation
6 year old male with history of mild intermittent asthma
24 hour history of coughing, wheezing, chest tightness
Symptoms began after football game
Albuterol inhaler 2‐4 puffs every 2 hours without relief
Started on Flovent MDI 2 weeks ago and compliant
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What do you do???
Initial Assessment
Rapid cardio‐pulmonary assessment
Avoid delays in treatment
NEVER delay oxygen supplementation for any child in distress
Detailed history and complete examination AFTER initial stablization
Assessment: History
Characteristics of child’s symptoms
Onset, duration, severity of symptoms
Verify potential risk factors
Medication use
Family history
Social history
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Assessment: Examination
General appearance
Vital signs
Respiratory rate: best indicator
Pulses paradoxus: >20 mm Hg
Accessory muscle use
Mental status
I:E ratio
Assessment: Ancillary Data
Pulse oximetry: “The fifth vital sign”
Non‐invasive
Poor sensitivity/specificity in predicting outcome
Peak expiratory flow monitoring
Effort depedent
<60% of predicted indicates severe obstruction
ABG, CXR
Management
Correct hypoxemia
Reverse airway obstruction
Treat the inflammatory response
Provide OXYGEN
Improves tissue oxygenation
Reduces pulmonary vasocontriction
Facilitates bronchodilation
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Treatment Options
Β‐adrenergic agonist
Anticholinergics
Corticosteroids
Magnesium
Methylxanthines
Leukotriene modifiers
Heliox
Mechanical ventilation
SABA (Short Acting Beta Agonist)
Mainstay of emergent treatment
Albuterol most widely used
Nebulizer vs. inhaler
Continuous delivery (CAT)
MDI vs. Nebulizer
MDI: acceptable alternative
Advantages: decreased cost, reduced administration time in ED, portability
Can be used in infants (need a mask on the end of the spacer)
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MDI vs. Nebulizer
MDI with spacer vs. nebulizer
Randomized, double‐blind, placebo‐controlled
60 children (1‐4 years)
No significant differences in clinical score, RR, O₂ saturation
MDI group: greater reduction in wheezing, fewer admissions, lower mean cost
Mandelberg A et al. Is Nebulized Aerosol Treatment Necessary in the Pediatric Emergency Department? Comparison with a Metal Spacer Device for Metered‐Dose Inhaler. Chest 2000;117:1309‐1313.
Continuous Delivery
Similar outcomes and side effect profiles with continuous vs. intermittent nebulized delivery
Less labor intensive
Ensures the goal of 3 treatments within the first hours of care
Young children may not tolerate wearing a facemask for long periods of time
Product Dose
Albuterol via nebulizer
0.15 mg/kg/dose (minimum 2.5mg, maximum 5mg/dose) every 20‐30 minutes for 3 doses, then 0.15‐0.3 mg/kg (maximum 10 mg) every 30 minutes to 4 hours as needed
Continuous albuterol therapy
0.5 mg/kg/hr (maximum 20mg/hr) by large volume nebulizer. Dose may also be determined based upon body weight:5‐10 kg: 7.5 mg/hr10‐20kg: 11.25 mg/hr>20 kg: 15 mg/hr
Albuterol MDI with spacer
4‐8 puffs every 20‐30 minutes for 3 doses, then every 1‐4 hours as needed (minimum 2 puffs/dose, maximum 8 puffs/dose)
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Systemic β‐adrenergic Agonist
Indications
Severe respiratory distress
Fail to respond to standard therapy
Epinephrine
Terbutaline
Epinephrine
0.01 mg/kg IM or SC (1:1000 concentration)
Maximum 0.4 mg/dose or 0.4 ml
Can repeat every 10‐20 minutes for 3 doses
Arrhythmias, tachycardia, hypertension, headaches, hyperglycemia, hypokalemia, nausea, vomiting
Terbutaline
0.01 mg/kg SC or IM
Maximum 0.25 mg/dose
Can repeat every 20 minutes for 3 doses
IV loading dose: 10 mcg/kg
Infusion rate: 0.4 mcg/kg/min titrated up to 3‐6 mcg/kg/min
Paradoxical bronchoconstriction
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Anticholinergics
Ipratropium bromide (Atrovent™)
Inhibits bronchoconstriction
Decreases mucus production
Not systemically absorbed
Minimal side effects
Administer in conjunction with β₂‐agonist
Dose: <20 kg = 250 mcg/dose; ≥20 kg = 500 mcg/dose
Combine with albuterol
Anticholinergics
Ipratropium bromide vs. saline
Randomized, double‐blind, placebo‐controlled
434 children (2‐18 years)
Lower admission rate for severe asthma
Qureshi F et al. Effect of Nebulized Ipratropium on the Hospitalization Rates of Children with Asthma. N Eng J Med 1998;339:1030‐1035
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Corticosteroids
Diminish airway inflammation
Potentiate effectiveness of β₂‐agonist
Moderate to severe exacerbation
Minimal improvement after single β₂‐agonist treatment
Prednisone or prednisolone PO
Methylprednisolone (Solumedrol™) IV
Dexamethasone (Decadron™) PO, IV, or IM
Corticosteroids
IV vs. PO steroids
Randomized, double‐blind, placebo‐controlled
49 children (18 months‐18 years)
2 mg/kg methylprednisolone PO or IV
Similar hospital admission rates, RR, O₂ saturation, PEFR, asthma score
Barnett PL et al. Intravenous Versus Oral Corticosteroids in the Management of Acute Asthma in Children. Ann Emerg Med 1997;29:212‐217.
Corticosteroids
IM dexamethasone vs. PO prednisone
Prospective, randomized, investigator blinded trial
32 children (6 months‐7 years)
1.7 mg/kg IM dexamethasone or 2 mg/kg/d x 5 days of PO prednisone
No significant differences in clinical asthma score or rate of improvement
Gries DM et al. A Single Dose of Intramuscularly Administered Dexamethasone Acetate is as Effective as Oral Prednisone to Treat Asthma Exacerbation in Young Children. J Pediatr 2000;136:298‐303.
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Product Dose
Prednisone or prednisolone
1‐2 mg/kg (maximum 60 mg/day) PO for first dose then 0.5‐1 mg/kg twice daily for subsequent doses for 3‐10 day course
Methylprednisolone 1‐2 mg/kg (maximum 125 mg/day) IV
Dexamethasone 0.6 mg/kg (maximum 16 mg/day) PO, IM, or IV
Magnesium Sulfate
Relaxes smooth muscle by blocking calcium induces muscle contraction
Inhibits release of acetylcholine
May diminish histamine induced bronchospasm
Hypotension, respiratory depression, hypermagnesemia, flushing, nausea, vomiting
25‐75 mg/kg/dose IV over 20 minutes (maximum single dose = 2 grams)
Magnesium Sulfate
Magnesium vs. placebo
Randomized, double‐blind, placebo controlled
30 children (6‐17 years)
40 mg/kg IV (maximum dose of 2 grams)
Significant improvement in PEFR, FEV₁, FVC
More likely to be discharged in magnesium group
Ciarallo, L et al. Higher‐Dose Intravenous Magnesium Therapy for Children with Moderate to Severe Acute Asthma. Arch Ped Adol Med 2000;154:979‐983.
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Theophylline
Weak bronchodilator
Little or no additional benefit
Difficult to titrate
Not recommended for routine use in ED
Leukotriene Modifiers
Montelukast (Singulair™)
Potent inflammatory mediator
Outpatient therapy
No role in acute asthma management
Heliox
Mixture of helium and oxygen (60:40)
Low density gas mixture
Decrease airway resistance, obstruction
Improve work of breathing
Limited use in hypoxic patients
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Heliox
Heliox (80:20) vs. room air
Randomized, double‐blind, controlled trial
18 children (16 months‐16 years)
Heliox at 10L/min by NRB face mask
Significant improvement in pulsus paradoxus, WOB, PEFR
Kudukis TM et al. Inhaled Helium‐Oxygen Revisited: Effect of Inhaled Helium‐Oxygen during the Treatment of Status Asthmaticus in Children. J Pediatr 1997;130:217‐224.
Mechanical Ventilation
1% asthma patients
Indications
Failure of maximal medical therapy
Depressed mental status
Severe hypoxia
Worsening hypercarbia
Respiratory or cardiac arrest
Rapid sequence intubation
Ketamine: also causes bronchodilatioin
Avoid high peak inspiratory pressure
No PEEP (minimize barotrauma)
What happened to Tommy?
Received 3 Duoneb treatments
2 mg/kg dose of Prelone
No oxygen requirement
Able to be observed for 4 hours post treatments
Sent home on 5 days of steroids
Follow up with pediatrician next day
Continue his Flovent MDI
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So Rapping up…
Goals of asthma treatment include reducing impairment and risk
Asthma education has many benefits including allowing patient/parents to become active partners in care
First determine asthma severity to determine the optimal medication regimen
If needed, supplemental oxygen is good for you
Frequent reassessment is key in acute management in ED
Thank You for Your Attention!