what’s new in asthma? - nsw agency for clinical innovation · 10-03-2014 · 1 hour consider...
TRANSCRIPT
What’s New in Asthma?
Kirsty ShortECI and St Vincent’s Hospital
Advanced Trainee
But Asthma’s Easy!? • New Australian guidelines released March 2014
• Lack of consensus between international guidelines
• No guidance on management of the crashing asthmatic beyond calling for help
• Lack of engagement of critical care specialties in Australian guideline development
• ECI involvement in Difficult Airway Society (DAS) guidelines
Comparison of Guidelines
Asthma in ED
• 2.3 million Australians in 2012
• 378 deaths in 2011, mainly in the elderly
• National Bureau of Statistics ‘Snapshots’
.... • .. .a I
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NationaiAsthma Counci !Australia
AUSTRALIAN ASTHMA HiANDBOOK
QUICK REFERENCE GUIDE
asthmahandbook.org.au VERSION 1.0
National Asthma Council Guidelines:2014 Changes
• Emphasis on primary and secondary assessment
• Allocation of asthma severity– Mild/mod grouped together – Severe– Life‐threatening
Secondary Asthma AssessmentSpeech
Posture
Breathing
Consciousness
Skin colour
Respiratory rate
Heart rate
Chest auscultation
Oxygen saturation (pulse oximetry)
Blood gas analysis (adults. if performed) t
Mild/ Moderate (all of):
Can finish a sentence in one breath
Can walk
Respiratory distress is not severe
Alert
Normal
<25 breaths/min
Adults:< 110 beats/min Children: normal range
Wheeze or Normal lung sounds
>94%
Not indicated
Severe (any of):
Can only speak a few words in one breath
Unable to lie flat due to dyspnoea
Sitting hunched forward
Paradoxical chest wall movement: inward movement on inspiration and outward movement on expiration (chest sucks in when person breathes in)
or Use of accessory muscles of neck or intercostal muscles or 'tracheal tug' during inspiration
or Subcostal recession t abdominal breathing')
t
t
~25 breaths/min
Adults: ~110 beats/min Children: tachycardia
t
90-94%
Not indicated
Life-threatening (any of):
Can't speak
Collapsed or exhausted
Severe respiratory distress or Poor respiratory effort
Drowsy or unconscious
Cyanosis
Bradypnoea (indicates respiratory exhaustion)
Cardiac arrhythmia or Bradycardia (may occur just before respiratory arrest)
Silent chest or Reduced air entry
<90%
or Clinical cyanosis
PaO, <60 mmHg PaC07 >50 mmHg§ PaC0
7within normal range
despite low Pa02
pH <7.35#
Guideline Changes
• More prescriptive O2 saturation targets• Inhaled route of bronchodilation preferred • Steroids for all in first hour • Out: Aminophylline • Revised IV salbutamol dosing regime • NPPV advocated, more studies required
What the Guidelines Don’t Cover
• Use of HFNP
• Approach to NPPV
• Intubating the asthmatic
• Adrenaline in the asthmatic without anaphylaxis
• What to do if there’s no ICU
ASSESS SEVERITY AND START BRONCHODILATOR Table U. Rapid primary assessment of acute asthma in adults and children
Can walk and speak whole sentences in
one breath
Give 4-12 ruffs salbutamo (100 meg per actuation) via pMDI plus spacer
REASSESS SEVERITY
Any of: unable to speak in sentences, visibly breathless, increased work of breathing, oxygen saturation 90-94%
Give 12 puffs salbutamol (100 meg per actuation) via pMDI plus spacer
OR rPrrnrttPnt nebulisation if patient
spacer. Give 5 mg nebuliser with air u
~ Life-threatening
Any of: drowsy, collapsed, exhausted, cyanotic, poor respiratory effort, oxygen saturation less than 90%
Give 2 x 5 mg nebules salbutamol via continuous nebulisation Start oxygen (if oxygen saturation less than 95%)
Table V. Secondary severity assessment of acute asthma in adults and children aged 6 years and over
CONTINUE BRONCHODILATOR Repeat dose every 20-30 mins for f irst hour i f needed (or sooner as needed)
IF POOR RESPONSE, ADD IPRATROPIUM BROMIDE Repeat every 4-6 hours as needed
~---.. CONTINUE BRONCHODILATOR Repeat dose every 20 minutes for first hour (3 doses) or sooner as needed
CONTINUE BRONCHODILATOR Continuous nebulisation until dyspnoea improves.
Then consider changing to pMDI plus spacer or intermittent nebuliser (doses as for Severe)
Give 8 puffs (160 meg) via pMDI (21 meg/actuation) every 20 minutes for f irst hour OR
Give 500 meg nebule via nebuliser added to nebulised salbutamol every 20 minutes for f irst hour
1 HOUR
CONSIDER OTHER ADD-ON TREATMENT OPTIONS Table X. Add-on treatment options for acute asthma
START SYSTEMIC CORTICOSTEROIDS
Oral prednisolone 37.5-50 mg then continue 5-10 days
OR, IF ORAL ROUTE NOT POSSIBLE
Hydrocortisone 100 mg IV every 6 hours
REASSESS RESPONSE TO Pertormspirometry(itpatientcapable) TREATMENT (1 HOUR AFTER Repeat pulse oximetry
STARTING BRONCHODILATOR) Check tor dyspnoea while supine
* * Dyspnoea resolved Dyspnoea persists
OBSERVE for more than 1 hour after dyspnoea resolves
PROVIDE POST-ACUTE CARE Ensure person (or carer) is able to monitor and manage asthma at home
Provide oral prednisolone for 5-10 days
Ensure person has regular inhaled preventer Check and coach in correct inhaler technique
Provide spacer if needed Provide interim asthma action plan
Advise/arrange follow-up review
i Persistin~
acute asthma
l • Persistin~
or life-threatenin~ acute asthma
Transfer to ICU or discuss transfer/retrieval with senior medical staff
ASSESS SEVERITY AND START BRONCHODILATOR Table U. Rapid primary assessment of acute asthma in adults and children
Can walk and SJ?eak whole sentences in one breath (Young children:
can move about and speak in phrases)
Give salbutamol (100 meg per actuation) via pMDI plus spacer (plus mask for younger children) 6 y ears and o ver : 4-12 puffs 0 -5 year s: 2-6 puffs
REASSESS SEVERITY
Any of: unable to speak in sentences, visibly breathless, increased work of breathing, oxygen saturation 90-94%
Give salbutamol (100 meg per actuation) via pMDI plus spacer (plus mask for younger children) 6 years and over: 12 puffs 0-5 years: 6 puffs
OR
• life-threatening Any of: drowsy, collapsed, exllausted, cyanotic., poor respiratory effort, oxygen saturation less than 90%
Give salbutamol via continuous nebullsatlon driven by oxygen 6 year s and over: use 2 x 5 mg nebules 0 - 5 years: use 2 x 25 mg nebules Start oxygen If oxygen saturation less than 95% T itrate to tar~et oxygen saturation of at least 95%
Table V. Secondary severity assessm ent of acute asthma in adults and children 6 yea rs and over
Table W . Secondary severity assessm ent of acute a sthma in children 0 -5 years
CONTINUE BRONCHODILATOR Repeat dose every 20- 30 mlns for first hour If needed (or sooner as needed)
• IF POOR RESPONSE, ADD IPRATROPIUM BROMIDE Repeat every 4-6 hours as needed
• -----CONTINUE BRONCHODILATOR Repeat dose every 20 minutes for first hour (3 doses) or sooner as needed
• CONTINUE BRONCHODILATOR Continuous nebullsatlon until breathing difficulty Improves. Then co nsider changing t o pMDI plus spacer or intermittent nebuliser (doses as for Severe)
6 years and over: 8 puffs (160 meg) via pMDI (21 meg/actuation) every 20 mrnutes for first hour 0-5 years: 4 puffs (80 meg) v ia pMDI (21 meg/actuation) every 20 minutes for first hour.
OR Give v ia nebuliser added to nebulised salbutamol 6 years and over: 500 meg nebule 0 -5 year s: 250 meg nebule
1 HOUR
• CONSIDER OTHER ADD-ON TREATMENT OPTIONS Table. Add-on treatment options for acute asthma
START SYSTEMIC CORTICOSTEROIDS
Oral prednisolone 2 mglkg oral (maximum 50 mg) then 1 mglkg on days 2 and 3 OR, if oral ro ute not possib le
Hydrocortisone IV initial dose 8 - 10 mg./kg (max 300 mg). then 4 - 5 rngl\<g/dose every 6 hours on day 1. then every 12 hours on day 2. then once on day 3
OR Methylprednisolone IV initial dose 2 mg/kg (max 60 mg). then 1 mg/kg every 6 hours on day 1, then every 12 hours on day 2, then once on day 3
.& For children 0 - 5 years, a110id systemic corticosteroids if mild/moderate wheezing responds to initial bronchodilator treatment
REASSESS RESPONSE TO TREATMENT (1 HOUR AFTER STARTING BRONCHODILATOR) Pcrtormspiromctrv(itchildcapablcl
I
• No breathing difficulty
OBSERVE for more than 1 hour after dyspnoea resolves
PROVIDE POST-ACUTE CARE Ensure parents are able to monitor and manage asthma at home Provide oral prednisolone for 3-5 days Ensure child has regular Inhaled preventer If Indicated Check and coach In correct Inhaler technique Provide spacer If needed Provide Interim asttlma :><:lion plan Advise/arrange follow-up review
• Breathing difficulty persists
REASSESS
1 No breathing
••••• difficulty for more than one hour
Breathing difficulty persists
L Persisting or
life-threatening acute asthma
Transfer to ICU or discuss transfer/retrieval with senior medical staff
SEVERITY ASSESSED AS LIFE-THREATENING ACUTE ASTHMA
Any of th~e findings:
• drowsy • poor respiratory effort • collapsed • soft/absent breath sounds • exha ust ed • oxygen saturat ion <90" • cyanotic
GIVE SALBUTAMOL VIA CONTINUOUS NEBULISATION
CHILDREN 0 -5 YEARS
Salbutamol2 x 2.5 mg nebules a t a t ime
Use oxycen to drive nebuliser Maintain Sa02 95"or hi&Mr
ADULTS AND ADOLESCENTS
Salbutamo12 x s mg nebules a t a time
Use ajr to drive nebuliser
Give oxvaen v~ wnturi mask and titrate to tarcet SaO, 92-95"
REASSESS IMMEDIATELY AFTER STARTING SALBUTAMOL
M ar ked Improvement Some Improvement
.e Adults and children 6years and over: 500 mcs ipratropium bromide
Children0-5 years: 250 mcs iprotropium bromide
If symptoms do not improve:
Add magnesium sulfate IV - diluted in saline as sina.Je IV infusion over a: 20minutes
Adults: 2 g MgS04
Children 2years and over:O.l-0.2 mmollkg MgS04
• • Symptoms resolved Symptoms not resolved
CONTINUE SALBUTAMOL AND MONITORING
When dyspnoea improves. consider chan,ains salbuumol route of deliv~
p MDI PLUS SPACER
Adults and children6yeorsand over: 12 puffs solbutamol 100 meg/actuation Children0-5 years: 6 puffs salbutamol 100mcg/actwtion
or
INTERMITTENT N EBULISATION
•
Adults and children 6 yeats and over: 5 mg nebule ~ 20 minutes Children0-5 yeors 2.5 mg nebuleevery 20minutes
• CONTINUE SALBUTAMOL BY CONTINUOUS NEBULISATION
CONSIDER THE NEED FOR NPPV OR INTUBATION AND VENTILATION
ARRANGE TRANSFER/RETRIEVAL TO ICU
Salbutamoi iV - initiollooding dose of 5 mcglkg/min lor 1 hour
Then reduce to 1-2 mcglkglmin until breothing stobilises.
.f.\. Monitor blood electrolytes. he~rt r~te Lll and acid/base balance (blood lactate)
The Difficult Airway Society UK
IV vs Nebulised Salbutamol
‘There is no evidence to support the use of IV beta2‐agonists in patients with acute severe asthma. These drugs should be given by inhalation. No subgroups were identified in which the IV route should be considered.’
Cochrane meta‐analysis 2003 and 2012
‘3rd line bronchodilator’Australian Asthma Handbook 2014
Really?
• 40 years of research• Cochrane reviewed 15 RCTs (level 1a/1b)• Criticisms:
– Poor case definition– Poorly controlled for age– Non‐equivalent therapies evaluated– No comment on serum salbutamol levels
AuthorYearLocation
Patient numbersneb: ivAgeWeight
Attack durationbefore treatment
Salbutamolnebulisation
Assumed10 minsalbutamol iv, if 70kg
Total IVsalbutamolover time
Result Side effects Blood levelssalbutamolng.ml‐1
Lawford 1978Single centre
7:715‐65yrsNo weight
Not stated
10mg in 10ml saline over 45 min
200mcg 900mcg over 45 min IV and nebulised groupsimproved
iv = pulse rise, shaking, ectopics
None
Cheong1982Single centre
34:3716‐69yrsNo weight
½ hr?unclear
5mg at 0, 30 and 120 min. No time of neb duration
125mcg 3000mcgOver 4 hours
IV more effective Tachycardiain iv groupat 3.5hr P<0.001
None
SwedishSociety199013 centres
87:8955 (13)Weightrecordedbut not used for iv
Not stated 5mg over 7min x2 at 0 and 30min delivery by IPPB on inhalation
350mcg 350mcgover 10 min
Neb betterthan iv
Tachycardiain neb group at 120 minP<0.001
Yes.Pre:postneb 7.1+/‐7:16+/‐9Iv 5.7+/‐6:6.6+/‐6.4 P<0.001
Salmeron19944 centres
22:2539 +/‐13yrsNo weight
14 +/‐ 16 hrs 5mg over 15min x2 during60 min
83 mcg 500mcgover 60 min
Neb betterNo differenceNS
Yes.Pre:postneb 2.9:7.8iv 3.6:10Non significant
Browne1997Single centre
15:148.4 (3.1)yrs29.2 (10.1)kgChildren
1 hr?unclear
2.5 or 5mg in 4ml saline.No time of nebulisation
1050 mcgFor a 70kg equivalent adult
438 mcgFor average 29.2kg child over 10 min
IV better.9.7hr earlier discharge from ED
Greater tremor in ivP<0.02
None.Assumed to be in the range of 20‐40
• 2002, Westmead Hospital• IV salbutamol/ipratropium neb/both• No side affects or treatment intolerance• Reduction in recovery time with IV salbutamol (p=0.008)
• Less supplemental oxygen required (p=0.0003)• Earlier discharge from hospital (p=0.013)
IV Magnesium Sulphate
‘Magnesium sulphate appears to be safe and beneficial in patients who present with severe acute asthma.’
Cochrane meta‐analysis 2012
‘2nd line bronchodilator’Australian Asthma Handbook 2014
• Are we giving enough?
• What can we learn from animal models?
• How should we dose effectively?
• Additional benefits?
The Magnesium Debate
• Magnesium and asthma meta‐analyses– Doses and administration times in asthma
• Experience in other clinical scenarios– O & G, cardiology
Author/year PatientsAge yrs
Presentation Co‐morbidity DoseIV MgSO4
Delivery speed
Result Side effects Other drugs Mg level
Iseri/1985 1052‐76
Atrial tachycardia COPDx7, CHF 2g Infusion
60 sec Ratedown
Not stated Theophyllinein 6
yes
Pritchard/1984 245 Pregnant Eclampsia 4g 4 min then im
One fatality20g iv in error
One blood level
Dicarlo/1986 1054+/‐12
Tests CardiomyopathyX6
6gInfusion
6 min Increase PR, AV refractoryA‐H interval
Warmth, flushing
yes
Wesley/1989 1020‐71
SVT inducedx5 1x CAD1x SSS
2g 5 sec SlowedSVT
X4 ventric triplet
Verapamil, digoxin, terbutaline,atropine
yes
Viskin/1992Mag vs Adenosine
14 SVT Mitral valve disease. A‐H= Atrial His interval
2g 15 sec Chest pain, flushing, nausea
Hays/1994 767+/‐16
New AF MVDHigh bp
2g 1 min Rate down warmth Digoxin yes
IV magnesium delivery. CAD=Coronary artery disease. SSS= Sick sinus syndrome. MVD= Mitral valve disease
The Magnesium Debate
• Magnesium and asthma meta‐analyses• Experience in other clinical scenarios• Cardiovascular safety profile• Magnesium levels• Pharmacological principles• Attenuation of catecholamine effects • Role for a rapid loading dose and infusion
Your 70kg Patient
National Asthma Council 2014 DAS Draft recommendations 2014
IV SalbutamolFirst 10 minsNext 50minsNext 1 hrTotal over 2 hr
3.5 mg17.5 mg4.2 mg25.2 mg
1.05 mg17.5 mg21.0 mg39.6 mg
IV Magnesium 2g over 20 minutes 2.8g over 4 minutes
ECI Clinical Tool on Asthma
• Importance of highlighting ongoing work and controversies
• Structured approach to the crashing asthmatic based on Australian experience
• Emphasis on collaboration and feedback
Procedure Pearls: the crashing patient with life threatening asthma 10 Mar 2014
• Keep sat up and on BIPAP until RSI drugs given, then lie down and apply BVM
• Place nasal prongs 15Umin for apnoeic oxygenation providing that placement of this does not
break your BVM seal 1 Preparation for intubation 11 Mar 2014 Avoid vigorously bagg --------------------------------
• hyperinflation, increas Airway and breathing: • Administer post-intubc; • Asthmatic patients are 'SOAP-ME'
permissive hypercapn • Suction
• Suggested settings: • Oxygen - BVM attached to oxygen Fi02 1.0, ongoing BIPAP • Airways (ETI, LMI
• SIMV- volume c• • Positioning- sit up Managing the deteriorating ventilated asthmatic 10Mar2014
• Fi02 1.0 • Monitoring and Me
• TV 8mUkg (ideal ! • Inspiratory flow ra
• PEEP 0-3cm H2C
• I:E ratio 1:4 ide all
• Plateau airway pr
Useful resources
'Dominating the Vent Par
• Continuous pu • Medications:
• Ketamine stability)
• Suxamett • If ketamin • Rocuronit • Sedative i
• End tidal C02
• Calibrate moni
Circulation:
• 2x large bore IV ca • IVF on pump set al
other cannula free • Give a fluid bolus ~
repeated.
ACI NSW Agency for Clinical Innovation
1. Immediately take off ventilator and allow patient to expire (can use both hands to press on chest to mechanically assist expiration)
2. Attach bag and 15Umin oxygen and gently ventilate assessing lung compliance 3. Assess 'MASH'
• Movement of the chest during ventilation
• Arterial saturation (Sa02) and Pa02 • Skin colour of the patient (are they turning blue or pinking up?) • Hemodynamic stability
4. Look for the cause of dl Pitta II~:
• Displacement of the ET Obstruction of the ETI
• Patient factors- inade• • Equipment- ventilator
• 'Stacked breaths' - AI<
5. Address the causes for 6. If you run into trouble v1
ventilator whilst awaitin,
ventilator.
• Not involving the most experienced airway doctor available
• Not involving your critical care colleagues
• Not appreciating or preparing for rapid patient deterioration:
Hypoxia and respiratory arrest
Hypotension and cardiovascular collapse - reduced preload with positive pressure
ventilation (these patients are pre-load dependant)
• Taking patient off BIPAP and lying patient flat pre delivery of RSI drugs
• Using conventional ventilation strategies
• Not adequately sedating and paralysing patient post intubation
• Failure to deliver nebulisers via the ventilation circuit
~ Emergency ~ Care Tnstitute
Where to from now?
High dose MgNIPPV
HFNP Trial ‐ RPA
World Asthma Day May 6th 2014
Thanks to
• Dr Sally McCarthy and Dr John Mackenzie (ECI)• Dr Willie Sellers and Dr Imran Ahmad (DAS)• Professor Mike James (anaesthetist, UCT)
References available on request