ACUTE SEVERE ASTHMA - look at pulmo and add Flashcards
etiology of asthma ?
genetic predisposition
environmental
allergens such as pollen , fungi , mold
domestic mites and furred animals
tobacco
clinical presentation of Acute severe asthma
Acute breathlessness and wheeze.
clinical features for asthma?
NON PRODUCTIVE cough
episodic breathlessness , tachypnea
tachycardia
prolonged expiration with wheezing
chest tightness
seasonal variability
allergic rhinitis
physical signs for asthma ?
decreased breath sounds
expiratory wheeze
percussion - hype resonant -
due to hyperinflation
Assessing the severity of an acute asthma attack
Severe attack: • Unable to complete sentences in one breath. • Respiratory rate ≥ 25/min. • Pulse rate ≥110 beats/min. • PEF 33–50% of predicted or best.
Life-threatening attack: • PEF <33% of predicted or best. • Silent chest, cyanosis, feeble respiratory eff ort. • Arrhythmia or hypotension. • Exhaustion, confusion, or coma. • Arterial blood gases: • Normal/high PaCO2 >4.6kPa.(45mmhg) • PaO2 <8kPa, or SaO2 <92%.
diagnosis for asthma ?
spirometry - obstruction
such that FEV1 is less than 80percent predicted,
and FEV1/FVC is less than 0.7
but in asthma normalises after attack
reversibility with bronchodilator
an increase in FEV1 of more than 12 percent
methacholin challenge test - hyper responsiveness of the ariwary
and FEV1 fall by 20 percent
peak expiratory flow - to measure the disease progression
skin allergen testing
blood hypercapni hypoxemia allergen specific iGe and serum igE and eosinophilia
xray hyperinflation in severe - flattened diaphragm wide intercostal space barrel chest
severity of the asthma ?
mild/intermittent symptoms such as wheezing dyspnea and coughing less than or equal to 2 days a week night time awakening - ≤ 2/month No interference with daily activities Use of SABA ≤ 2 days/week FEV1> 80 percent predicted Normal FEV1/FVC exacerbation requiring corticosteroids equal to or less than 1
mild persistant more than 2 days a week night time awakening 3-4 times a month Use of SABA > 2 days/week Minor limitation of daily activities FEV1 >80 percent predictyed Normal FEV1/FVC corticosteroids equal to or more than 2
moderate persistant symptoms daily night time - >1 times a week Some limitation of daily activities Daily use of SABA FEV1 60-80 predicted ↓ FEV1/FVC by < 5% corticosteroids equal to or more than 2
severe symptoms throughout the days night time - nightly Extreme limitation of daily activities Use of SABA several times a day FEV1 < 60% predicted ↓ FEV1/FVC by ≥ 5%
dd of asthma
Acute infective exacerbation of COPD, pulmonary oedema,
upper respiratory tract obstruction, pulmonary embolus, anaphylaxis
management of acute asthma?
A-E
Supplemental O2 to maintain sats 94–98%
===========
Assess severity of attack:
PEF, ability to speak, RR, pulse rate, O2 sats
Warn ICU if severe or life-threatening attack
===========
Salbutamol 5mg (or ORAL terbutaline 10mg) nebulized with O2
If severe/life-threatening add in ipratropium 0.5mg/6h to nebulizers
Hydrocortisone 100mg IV or prednisolone 40–50mg PO
==================
Reassess every 15min:
- If PEF <75% repeat salbutamol nebulizers every 15–30min. Add ipratropium if not already given
- Monitor ECG; watch for arrhythmias
• Consider single dose of magnesium sulfate (MgSO4) 1.2–2g IV over 20min in those with severe/life-threatening features
without good initial response to therapy
===============
If not improving: Refer to ICU for consideration of ventilatory support and intensification of medical therapy, eg aminophylline, IV salbutamol if any of the following signs are present: • Deteriorating PEF • Persistent/worsening hypoxia • Hypercapnia • ABG showing low pH or high H+ • Exhaustion, feeble respiration • Drowsiness, confusion, altered conscious level • Respiratory arrest
================
If improving within 15–30min: • Continue nebulized salbutamol every 4–6h (+ ipratropium if started in previous step) • Prednisolone 40–50mg PO OD for 5–7 days • Monitor peak fl ow and O2 sats, aim 94–98% with supplemental if needed • If PEF >75% 1h after initial treatment, consider discharge with outpatient follow-up
what is the stepwise management of asthma ?
preferred reliever for all low dose ICS - formeterol (LABA) or inhaled SABA
===========
step wise approach the controllers
mild intermittent
SABA
mild persistant low dose ICS or LTRA ( or theophylline / cromolyn ) and SABA as needed
moderate persistant
low dose ICS - LABA (formoterol) (/Lama / LTRA/ THEOPHYLINE )
severe persistant
medium TO HIGH dose ICS - LABA + LAMA (LTRA/THEOPHYLINE)
consider omalizimuab for allergies (blocking igE)
========
high dose ics-LABA + oral corticosteroid
sonder biologics for severe asthma
what are the inhaled corticosteroids ?
Budesonide
Fluticasone
Mometasone
Others: beclomethasone,
what are the oral corticosteroids ?
Methylprednisolone
Prednisone
what are the normal SABA?
Inhaled: albuterol
what are the usual LABA?
Salmeterol
Formoterol
what are the usual LTRA
Montelukast
Zafirlukast
