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Status Asthmaticus Management
Amina Al-Qaysi
Status Asthmaticus• Acute exacerbation of asthma that is severe at
its onset or progresses rapidly despite standard therapy, and remains unresponsive to initial treatment with bronchodilators.
• Usually occur during sleep when airway inflammation & hyperresponsiveness
are at their peak.
Management1. Focused history2. Clinical assessment3. Risk factors for asthma morbidity & mortality4. Treatment
1. Focused History:
• Onset of current exacerbation• Frequency & severity of daytime & night time
symptoms, activity limitation• Frequency of rescue bronchodilator use• Current medications, allergies• Potential triggers• Hx of systemic steroid courses, ER visits,
hospitalization, intubation, or life-threatening episodes.
2. Clinical Assessment:
• Vital signs• Breathlessness, air movement, accessory
muscles use, retractions, anxiety, mental status alteration• Pulse oximetry• Lung function (defer if Pt with moderate-
severe distress)
Manifestation Mild Moderate Severe
Alertness Normal Agitated May be drowsy
Dyspnea Absent, speaks complete sentence
Speaks short phrases, soft short cry
Speaks short phrases, words
Pulsus paradoxus (mmHg)
Less than 10 10-25 25-40
Accessory muscle use None Retractions, sternocleidomastoid
Severe retractions, nasal flaring
Skin color Good Pale Cyanotic
Auscultation End-expiratory wheeze
Inspiratory, expiratory wheeze
Quiet breath sounds
O2 saturation (%)PCO2 (mm Hg)PEFR (% of predicted or best)
More than 95Less than 42More than 80
91-94Less than 4250-80
Less than 91More than or equal 42Less than 50
3. Risk Factors for Asthma Morbidity & Mortality:• Biologic:Previous severe asthma exacerbationSevere airflow obstructionHx of rapidly occurring attacksSevere airway hyper-responsivenessIncreasing & large diurnal variation in peak flowsDecreased chemosensitivity and perception of
dyspneaPoor response to systemic corticosteroid therapyLow birth weightMale gender, Non-white ethnicity
• Environmental:Allergen exposureEnvironmental tobacco smoke exposureAir pollution exposureUrban environment• Economic & Psychological:Poverty, Crowding, Mother younger than 20 yrMother with less than high school educationInadequate medical carePsychopathology in the parent or childFamily problemsAlcohol or substance abuse
4. Treatment
• Oxygen: Mask or nasal cannula
• Monitor pulse oximetry• Maintain oxygen saturation higher than 92%• Cardio-respiratory monitoring
Drug MOA & DosageInhaled short-acting B agonist Bronchodilation
Albuterol nebulizer solution (5 mg/ml concentrate; 2.5 mg/3ml, 1.25 mg/3ml, 0.63 mg/3ml)
Nebulizer: 0.15 mg/kg (minimum 2.5 mg)every 20 min for 3 doses as needed, then 0.15-0.3 mg/kg up to 10 mg every 1-4 hr as needed, or up to 0.5 mg/kg/hr by continuous nebulization
Albuterol MDI (90 Mg/puff)
Levalbuterol (Xopenex) nebulizer solution (1.25 mg/0.5 ml concentrate, 0.31 mg/3ml, 0.63 mg/3ml, 1.25 mg/3ml)
2-8 puffs up to every20 min for 3 doses as needed, then every 1-4 hr as needed
0.075 mg/kg (minimum 1.25 mg) every 20 min for 3 doses, then 0.075-0.15 mg/kg up to 5 mg every 1-4 hr as needed, or 0.25 mg/kg/hr by continuous nebulization
• Nebulizer: when given concentrated forms, dilute with saline to 3 ml total nebulized volume
• For MDI use spacer/holding chamber
• During exacerbations, frequent or continuous doses can cause pulmonary vasodilatation, V/Q mismatch, & hypoxia
• Levalbuterol 0.63 mg is equivalent to 1.25 mg of standard albuterol for both efficacy & AE
• AE: palpitations, tachycardia, arrhythmias, tremor, hypoxemia
Systemic Corticosteroids Anti-inflammatory
Prednisone1, 2.5, 5, 10, 20, 50 mg tablets
Methyl-Prednisolone (Medrol)2, 4, 8, 16, 24, 32 mg tablets
Prednisolone5 mg tablets; 5 mg/5 ml and 15 mg/5 ml solution
Depo-Medrol (IM), Solu-Medrol (IV)
0.5-1 mg/kg every 6-12 hr for 48 hr, then 1-2 mg/kg/day bid (maximum 60 mg/day)
Short course burst for exacerbation: 1-2 mg/kg/day qd or bid for 3-7 days
• Systemic Corticosteroids
• If exposed to chicken pox or measles, consider passive Ig prophylaxis. Also risk of complications with herpes simplex & TB
• For daily dosing, 8 AM administration minimizes adrenal suppression
• Children may benefit from tapering if course exceeds 7 days
Anticholinergics Mucolytic/Bronchodilator
IpratropiumAtrovent (nebulizer solution 0.5 mg/2.5 ml; MDI 18 Mg/inhalation)
Ipratropium with albuterolDuoNeb nebulizer solution (0.5 mg ipratropium + 2.5 mg albuterol/3 ml vial)
Nebulizer :0.5 mg q6-8 hr (tid-qid) as neededMDI 2 puffs qid
1 vial by nebulizer qid
• Anticholinergics:
• Shouldn’t be used as first line therapy; added to B2-agonists
• Nebulizer: may mix ipratropium with albuterol
Injectable Sympathomimitics Bronchodilator
EpinephrineAdrenalin 1 mg/ml (1:1000)EpiPen autoinjection device (0.3 mg; EpiPen Jr 0.15 mg)
TerutalineBerthine 1mg/ml
SC or IM: 0.01 mg/kg (maximum dose 0.5 mg); may repeat after 15-30 min
Continuous IV infusion (terbutaline only): 2-10 Mg/kg loading dose, followed by 0.1-0.4 Mg/kg/min. Titrate in 0.1-0.2 Mg/kg/min increment every 30 min, depending on clinical response
• Injectable Sympathomimitics
• For (extreme circumstances e.g. Impending respiratory failure despite high dose inhaled SABA, respiratory failure)
• Terbutaline is B-agonist selective relative to epinephrine
• Monitoring with continuous infusion: cardiorespiratory, pulse oximetry, BP, serum K
• AE: tremor, tachycardia, palpitations, arrhythmias, HTN, headache, nervousness, nausea, vomiting, hypoxemia
Risk assessment for discharge
• Medical stability: symptoms improvement, bronchodilator tt are at least 3 hr apart, normal physical findings, PEF 70% of predicted or personal best, O2 saturation 92% on room air
• Home supervision: capability to administer intervention, and observe and respond to clinical deterioration
• Asthma education
Respiratory DistressManagement
Respiratory Distress• Clinical condition of increased Respiratory Rate &
use of accessory muscles of respiration.• Can progress into respiratory failure (clinical
condition of inadequate oxygenation or ventilation).
• It’s the primary diagnosis of 50% of patients admitted to the paediatrics ICU
CausesLUNG:• Central airway obstruction
• Peripheral airway obstruction
• Diffuse alveolar damage
RESPIRATORY PUMP:• Chest wall deformity
• Brainstem
• Spinal cord
• neuromuscular
Management• Emergency management: ABCDE.• In patient is not in impending respiratory failure
then non-invasive methods of respiratory support should be tried before initiating mechanical ventilation
• Advantages of non-invasive ventilation:1. Decreased risk of pneumonia.2. No risk of developing ventilator-induced lung
injury.3. Need for less overall sedation.
Oxygen Only Nasal cannula
Simple face mask
Non-rebreather face mask
Deliver up to 4 L O2Deliver up to 10 L O2Deliver up to 15 L O2
Oxygen + non-invasive pressure support
Nasal CPAP; effective in neonates & patients less than 8 Kg
BiPAP; in older children or patients more than 8 Kg
Can provide continuous positive airway pressure with a backup rate
Can provide 2 levels of support with inspiratory positive airway pressure & expiratory positive airway pressure
Non-Invasive Modes of Respiratory Support
• Goal of treatment is the restoration of adequate gas exchange with a minimum of complications.
• Eliminate the initiating factors as quickly as possible.
• Unfortunately, in these acute illnesses the response to treatment is not immediate and frequently the respiratory function must be artificially supported.
• Hypoxemia is more dangerous than hypercarbia.• Administration of supplemental oxygen is a safe
and wise precaution in all patients even in the absence of initial evidence of hypoxemia.
• Mechanical ventilation is necessary in patients of pneumonia with severe hypoxemia and hypercarbia because even the most effective antibiotic therapy require time (at least 24 hrs)
• Ventilatory support must be initiated in the absence of alterations in arterial PCO2 when dysfunction of other systems places gas exchange at jeopardy (e.g. Cardiovascular shock).
References:
• Nelson Textbook of Pediatrics, 18th Edition, Page 421-424, 966-969.
• Ski’s Essential Pediatrics, 2nd edition, Page 654-659.