Download Management of Asthma Exacerbations

le urgenze pneumologiche in pronto soccorso
Pavia, 24 novembre 2006
LA CRISI ASMATICA
Angelo Corsico
Clinica di Malattie dell’Apparato Respiratorio
Fondazione IRCCS Policlinico S.Matteo
Università di Pavia
le urgenze pneumologiche in pronto soccorso
Pavia, 24 novembre 2006
 Premessa
 Gestione delle crisi asmatiche
 La gestione in Pronto Soccorso
 Altri trattamenti
Six-part Asthma Management Program
Part 5: Managing Severe Asthma
Exacerbations
 Severe exacerbations are life-threatening
medical emergencies
 Care must be expeditious and treatment is
often most safely undertaken in a hospital or
hospital-based emergency department
Adult and child asthma emergency department
rates, United States: 1992–2001
140
Children
Rate per 10,000
120
100
80
Adults
60
40
20
0
92
Source: National
94
96
98
2000
Hospital Ambulatory Care Survey; National Center for Health Statistics
During exacerbations: a linear decline of PEF over a period of a
few days, a sharp point of inflection, then a linear increase.
During poor asthma control: wide diurnal variability and
bronchodilator reversibility.
Reddel, Lancet 1999
EMERGENCY VISITS FOR ASTHMA
Policlinico San Matteo, Pavia 2002
% OF SUBJECTS WITH ED ADMISSIONS
BY CAUSES OF ASTHMA ATTACK
Severe asthma
7%
Poor asthma control
(inadequate
treatment)
Clinical
respiratory
infections
64%
15%
Acute exposure to
allergens or other
triggers
14%
Cerveri et al. ATS 2004
CONSENSUS DEFINITION
OF ACUTE SEVERE ASTHMA
Rapid exacerbation characterized by one or more of
the following features:
 Accessory muscle activity
 Paradoxical pulse exceeding 25 mmHg
 Heart rate > 100 beats/min
 Respiratory rate > 25-30 breaths/min
 Limited ability to speak
 PEF rate or FEV1 < 50% pred.
 Arterial oxygen saturation < 91-92%
McFadden, AJRCCM 2003
Deaths Due to Asthma,
United States, 1979-2001
age group
0 to 4
5 to 14
15 to 34
35 to 64
65 +
6000
5000
4000
3000
2000
1000
0
Year
Source: Compressed Mortality Files
Our study indicates that 1,499 deaths (33% of all 4,487
deaths from asthma in the United States in 2000) occurred
in patients hospitalized for asthma exacerbations.
Improvements in the management of asthma
exacerbations before hospitalization (e.g., at home, during
transportation to the emergency department) will have the
greatest benefit in further reducing the overall risk of
death.
Krishnan, AJRCCM 2006
263 potential asthma-related athletic deaths between July 1993 and
December 2000.
 The subjects were usually white male aged 10 to 20 years.
 Mild intermittent or persistent asthma by history was commonly
identified.
 Sudden fatal asthma exacerbations occur in both competitive and
recreational athletes and can be precipitated by sporting activity.
The positive benefits to an active lifestyle cannot be negated by the
risks outlined here.
Becker, JACI 2004
le urgenze pneumologiche in pronto soccorso
Pavia, 24 novembre 2006
 Premessa
 Gestione delle crisi asmatiche
 La gestione in Pronto Soccorso
 Altri trattamenti
Key Points
Early treatment is best. Important elements:
–
A written action plan
 Guides
patient self-management at home
 Especially important for patients with moderate-to-severe
persistent asthma and any patient with a history of severe
exacerbations
–
–
Recognition of early signs of worsening asthma
Prompt communication between patient and clinician
about:
 Serious
deterioration in symptoms or peak flow, or
 Decreased
responsiveness to inhaled
beta2-agonists, or
 Decreased
duration of beta2-agonist effect
Risk Factors for
Death From Asthma
Past history of sudden severe exacerbations
 Prior intubation or admission to ICU for asthma
 ≥2 hospitalizations for asthma in the past year
 ≥3 ED visits for asthma in the past year
 Hospitalization or an ED visit for asthma
in the past month


Use of >2 canisters per month of inhaled shortacting beta2-agonist
Risk Factors for
Death From Asthma (continued)

Current use of systemic corticosteroids or recent
withdrawal from systemic corticosteroids
Difficulty perceiving airflow obstruction
or its severity
 Comorbidity, as from cardiovascular diseases or
chronic obstructive pulmonary disease
 Serious psychiatric disease or psychosocial
problems

Risk Factors for
Death From Asthma (continued)

Low socioeconomic status and
urban residence

Illicit drug use

Sensitivity to Alternaria
Six-part Asthma Management Program
Part 5: Establish Plans for Managing
Exacerbations
Primary therapies for exacerbations:
 Repetitive administration of rapid-acting
inhaled β2-agonist
 Early introduction of systemic
glucocorticosteroids
 Oxygen supplementation
Closely monitor response to treatment
with serial measures of lung function
Six-part Asthma Management Program
Part 5: Establish Plans for Managing
Exacerbations
Treatment of exacerbations depends on:
 The patient
 Experience of the health care professional
 Therapies that are the most effective for the
particular patient
 Availability of medications
 Emergency facilities
le urgenze pneumologiche in pronto soccorso
Pavia, 24 novembre 2006
 Premessa
 Gestione delle crisi asmatiche
 La gestione in Pronto Soccorso
 Altri trattamenti
Brief Physical Exam
Assess severity: Alertness, distress,
accessory muscle use, tachycardia,
tachypnea, pulsus paradoxus, cyanosis
 Identify complications (e.g., pneumonia,
pneumothorax, pneumomediastinum)
 Identify diseases that affect asthma
(otitis, rhinitis, sinusitis)
 Rule out upper-airway obstruction

Functional Assessment
Measure FEV1 or PEF:
 Upon presentation (begin treatment as soon as
asthma exacerbation is recognized)
 At intervals depending on response to therapy
 Before discharge
Monitor SaO2 in patients with severe distress
or with FEV1 or PEF <50% predicted
Brief History
(after treatment is initiated)

Time of onset and cause of exacerbation

Severity of symptoms, especially compared to
previous attacks

All current medications and time of last dose

Prior hospitalizations and ED visits, especially in
past year

Prior episodes of respiratory failure or loss of
consciousness due to asthma

Existence of comorbidities
Laboratory Assessment
Consider ABG in patients with suspected
hypoventilation, severe distress, or with FEV1
or PEF <30% predicted after initial treatment
 CBC may be appropriate in patients with
fever or purulent sputum
 Serum theophylline concentration
 Serum electrolytes, chest x-ray, ECG in
special circumstances

Emergency Department and
Hospital Management: Goals
 Correction
 Rapid
of significant hypoxemia
reversal of airflow obstruction
 Reduction
of likelihood of recurrence
Initial Treatment

Oxygen to achieve O2 saturation >90%

FEV1 or PEF >50%: Inhaled beta2-agonist by
metered-dose inhaler or nebulizer, up to three
treatments in first hour

FEV1 or PEF <50%: Inhaled high-dose beta2-agonist
and anticholinergic by nebulization every 20 minutes
or continuously for 1 hour

Oral corticosteroids

Repeat assessment (symptoms, physical exam, PEF,
O2 saturation, other tests as needed)
Initial Treatment (continued)
Impending or Actual Respiratory Arrest




Intubation and mechanical ventilation with 100% O2
Nebulized beta2-agonist and anticholinergic
Intravenous corticosteroid
Admit to hospital intensive care
Treatment After Repeat Assessment
• Physical exam: moderate
symptoms
• FEV1 or PEF > 50%
predicted or personal best
• Inhaled short-acting beta2agonist every 60 minutes
• Systemic corticosteroid
• Continue treatment 1 to 3
hours, provided there is
improvement
• Physical exam: severe
symptoms at rest, accessory
muscle use, chest retraction
• History: high-risk patient
• FEV1 or PEF <50% predicted
or personal best
• No improvement after initial
treatment
• Oxygen
• Inhaled short-acting beta2agonist hourly or continuously
+ inhaled anticholinergic
• Systemic corticosteroid
Emergency Department and
Hospital Management
Not generally recommended:




Methylxanthines
Antibiotics (except for patients with pneumonia,
bacterial sinusitis)
“Aggressive” hydration
Chest physical therapy
Not recommended:


Mucolytics
Sedation
Good
Response
• No distress
• Physical exam:
normal
• FEV1 or PEF >70%
• Sustained response
@ 60 min after last
treatment
• Discharge Home
Incomplete
Response
• Mild-tomoderate
symptoms
• FEV1 or PEF
50% to 70%
Poor
Response
• Physical exam:
symptoms severe,
drowsiness,
confusion
• PCO2 >42 mm Hg
• FEV1 or PEF <50%
• Individualized
decision:
hospitalization
• Admit to hospital
or intensive care
Hospitalization
Consider:






Duration and severity of airflow obstruction
Course and severity of prior attacks
Medication use
Access to care
Home conditions and support
Comorbidities
Admit to Hospital Intensive Care
• Inhaled beta2-agonist hourly or
continuously + inhaled anticholinergic
• IV corticosteroid
• Oxygen
• Possible intubation and mechanical
ventilation
• Admit to hospital ward
Emergency Department
Discharge Criteria

If FEV1 or PEF 70% predicted and symptoms
are minimal, discharge

If FEV1 or PEF >50% but <70% predicted and
symptoms are mild, decision is individualized

If response is prompt, observe for
30 to 60 minutes before discharging
Emergency Department and
Hospital Discharge Actions

Prescribe sufficient medication and instructions
for use

Schedule follow-up or referral visit within 3 to 5 days
– Consider referral to specialist if patient has history of
life-threatening exacerbations or multiple hospitalizations

Teach correct inhaler use and trigger avoidance
Hospital Discharge
Actions (continued)

Discharge medications should include:
– Short-acting beta2-agonist
– Sufficient oral corticosteroid to complete course
of therapy (3 to 10 days) or to continue therapy
until followup appointment
– If inhaled corticosteroids are prescribed,
start before course of oral corticosteroids
is completed
le urgenze pneumologiche in pronto soccorso
Pavia, 24 novembre 2006
 Premessa
 Gestione delle crisi asmatiche
 La gestione in Pronto Soccorso
 Altri trattamenti
Intravenous magnesium
(MgSO4)

Is effective at improving airflow and reducing
admissions in very severe asthma
exacerbations (eg, 40% of predicted PEF).

Has few adverse effects, is inexpensive, and
is easy to administer.

Rapid adoption of this therapy in North
American EDs.
Intravenous leukotriene modifiers

Data on intravenous montelukast suggest
that leukotriene modifiers have important
bronchodilating effects and that this adjunct
therapy may prove useful.

The relatively slow onset of action of oral
agents will limit their usefulness in the
management of truly severe exacerbations.
Intravenous epinephrine

In some Australian EDs is commonly used to treat
the acute bronchospasm, initiate adequate
antiinflammatory treatment, and avoid the risks and
complications associated with intubation.

Theoretically it may control airway edema but its
use needs to reflect a balance between clinical
efficacy and safety.

Evidence on therapeutic safety is difficult to collect
and research.

Epinephrine should not be the first step in treating
these patients.
PEF ~ 70%
PEF ~ 50%
EMERGENCY VISITS FOR ASTHMA
Policlinico San Matteo, Pavia 2002
Without
previous admission
With frequent admission
40%
60%
With one
previous admission
Cerveri et al. ATS 2004