2. Objectives
● Definition of Asthma
● Definition of status Asthmaticus
● Pathophysiology of status
Asthmaticus
● Causes of status Asthmaticus
● Clinical features
● Laboratory findings
● Treatment
● Prognosis
3. What is Asthma ?
Chronic inflammatory disorder of the medium and small airways
These airways are hypersensitive to certain “ triggers “ in the
environment
Intermittent and recurrent episodes of …
-Wheezing
-Shortness of breath
-Chest tightness
-Cough - night , early morning
Condition is usually reversible
4. STATUS ASTHMATICUS IN CHILDREN
Status Asthmaticus is a life threatening form of Asthma
defined as “ a condition in which severe
bronchoconstriction is unresponsive to the usual
appropriate therapy with inhaled bronchodilators and
anti-inflammatory agents that may progress to
respiratory failure without prompt and aggressive
intervention
5. Pathophysiology
Life threatening asthma exacerbation are caused by
severe Bronchospasm, airway inflammation, and increased
mucus production..This pathophysiology results in
increased pulmonary resistance, small airway collapse, and
dynamic hyperinflation. Unlike during normal breathing, in
status asthmaticus a child’s inspiratory muscle activity can
persist through exhalation, significantly increasing
respiratory muscle workload and fatigue.
6. ● Infants and children are at particular risk
for respiratory failure from asthma due to
several structural and mechanical
features if their lungs
● They have less elastic recoil than adult
lung , thicker airway walls leading to
greater peripheral airway resistance for
any degree of bronchoconstriction , fewer
collateral channels of ventilation
● They have more compliant chest wall
which can lead to increased work of
breathing with airway obstruction.
7. Causes of Status Asthmaticus
● Infection (viral )
● Anxiety
● Nebuliser abuse
● Dehydration
● Ingestion of aspirin and other NSAIDS
● Increased adrenergic blockade by B adrenergic blocker
ingestion
● Non specific irritants may contribute to these episodes
● Poorly controlled asthma
8. Clinical features
Red Flags signals
- Dyspnea ( precluding speech )
- Accessory muscle use
- Respiratory rate> 50/ mint
- Heart rate > 140 / mint
- Peak expiratory flow < 100l / mint
- Hypercapnia
- Excessive Diaphoresis
9. Life threatening features ( Should be
admitted to PICU )
● Cyanosis (with 60% oxygen )
● Silent chest on auscultation
● Feeble respiratory effort
● Fatigue or exhaustion
● Agitation
● Reduced level of consciousness
10. Stage 1 of Status Asthmaticus relative
compensation, as a result of resistance to
sympathomimetics
● Frequent occurrence of prolonged attacks of asthma during the day, between attacks of
breathing is not fully restored.
● Paroxysmal, painful, dry cough with sputum that is difficult to pass.
● Forced position (orthopnea), accelerated breathing (up to 40 in 1 min.) with the
participation of auxiliary respiratory muscles.
● Breathing noises and dry wheezing can be heard in
● At percussion of the lungs – box sound (emphysema of the lungs), auscultation –
"mosaic" breathing: in the lower lungs is not heard, in the upper – hard with a moderate
amount of dry rales.
● As to the cardiovascular system – tachycardia up to 120 per minute
● Signs of central nervous system dysfunction - irritability, agitation, sometimes delirium,
hallucinations.
11. Stage 2 of Status Asthmaticus- Stage of
decompensation “ silent lung “
● Extremely serious condition of patients.
● Sharply pronounced shortness of breath, shallow breathing, the patient
"catches his breath."
● The position is forced, orthopnea.
● The skin is pale gray, moist.
● Periodically there is excitement, which is replaced by indifference.
● At auscultation of lungs – over all surface of lungs or on a big site of both
lungs respiratory noises ("dumb lung", obturation of bronchioles and
bronchial tubes) are not listened, only on a small site a small amount of rales
can be heard.
● Cardiovascular system – pulse becomes more frequent (up to 140 per
minute), weak filling, arrhythmias, hypotension, deaf heart tones, possible
gallop rhythm.
12. Stage 3 of Status Asthmaticus- hypercapnic
coma
● Unconscious patient, convulsions are possible before loss of
consciousness.
● Spilled diffuse "red" cyanosis, cold sweat.
● Superficial, liquid, arrhythmic respiration (possibly Cheyne-Stokes
respiration).
● At auscultation of lungs: absence of respiratory noises or their sharp
weakening.
● Cardiovascular system: pulse filamentous, arrhythmic, blood pressure is
sharply reduced or undetectable, collapse, deaf heart sounds, often
gallop rhythm, possible ventricular fibrillation.
15. “The longer it lasts , the worse it
gets, and the worse it gets, the longer
it lasts “
16.
17. Initial Management
● Give high flow oxygen via tight fitting face mask to achieve saturations 94% or
above
● Continuous monitoring of heart rate and oxygen saturation
● Continue nebulised Salbutamol therapy
● Ensure the child has received oral steroids
(if oral steroids not tolerated, see IV hydrocortisone below)
● If a child is already on daily steroids increase the dose to 2 mg/kg (maximum
60mg)
● Children with clinical signs of dehydration should receive appropriate fluid
resuscitation.
● Assess response to initial treatment
18. Do they have life threatening presentation
If yes the commence nebulisers and
proceed IV
● IV SALBUTAMOL( short acting beta 2 agonist)
● Salbutamol for injection comes in 2 concentrations:
● 500 micrograms in 1ml or 5mg in 5ml (1mg/ml).
● Loading Dose
● The LOADING dose of salbutamol is 15 micrograms/kg
(maximum 250 micrograms) slow injection over 5-10
minutes.
● Infusion Dose
● INFUSION dose for salbutamol is 1-5micrograms/kg/min.
Rates should be adjusted according to response.
19. If not responsive to initial therapy
● 1. Magnesium Sulphate (MgSO4)
● Cause bronchodilation by interference with calcium influx in bronchial
smooth muscle .
● Drug dose
● The dose is 40mg/kg or 0.16mmols/kg (max. 2 grams)
● Hypotension and flushing may occur and should be anticipated with
adequate fluid resuscitation
● 2. IV AMINOPHYLLINE
● Relaxation of airway smooth muscle by preventing degradation of cyclic
guanosine monophosphate
● Drug dose
● The LOADING dose of aminophylline is 5mg/kg
● (5mls/kg of 1mg/ml solution) over 20 minutes (Maximum dose 500mg)..
20.
21. Monitoring Requirements
Children with severe asthma requiring intravenous
therapy are high dependency (HDU) patients
requiring close monitoring.
● Continuous ECG and saturation monitoring is
necessary for patients on aminophylline and/or
salbutamol infusions.
22. Non invasive ventilation
● Used to support patients
with severe asthma
exacerbations and help avoid
the need for intubation and
mechanical ventilation.
● Positive pressure ventilation
may help avoid airway
collapse during exhalation as
well as to unload fatigue
respiratory muscle
● Careful titration of
inspiratory and expiratory
pressure is Essential , to
avoid complication of
positive pressure
Invasive ventilation
● If aggressive management
fails , endotracheal
intubation and mechanical
ventilation may be
necessary
● Patient presents with
apnea or coma should be
intubated immediately
23.
24. Clinical Review
● Conscious Level.
● Oxygen saturations and oxygen requirement
in litres/minute.
● Significant hypoxia (SpO2 <92%, or significant
oxygen requirement >6l/min to maintain
normal oxygen saturation) is indicative of
severe asthma.
● Heart rate – Compare to normal range for age.
● Increasing tachycardia generally denotes
worsening asthma but remember that
B2agonists increase heart rate.
25. ● Blood Pressure
● Respiratory Rate – Compare to normal
range for age.
● Posture / position of patient.
● Ability to talk in words, phrases or
sentences
● Degree of Respiratory Distress / Use of
accessory muscle and recession
● Air entry - including any clinical suspicion
of pneumothorax or significant collapse
and amount of wheezing including
biphasic or silent chest
26.
27. Prognosis
● Status Asthmaticus remains among the most common
reasons for admission to the PICU
● High mortality rate ( 1%-3% )
● 75% of patient admitted to PICU will be readmitted with
a future exacerbation
● Careful outpatient follow -up of high risk population.
