Whats New in Asthma? Kirsty Short ECI and St Vincents Hospital - - PowerPoint PPT Presentation

What’s New in Asthma?

Kirsty Short ECI 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

• ~.:,._.-_.-~

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 Assessment

Speech

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

• ne

breath Can walk Respiratory distress is not severe Alert Normal <25 breaths/min Adults:< 110 beats/min Children: normal range Wheeze

• r

Normal lung sounds >94% Not indicated Severe (any of): Can only speak a few words in

• ne breath

Unable to lie flat due

to

dyspnoea Sitting hunched forward Paradoxical chest wall movement: inward movement

• n inspiration and
• utward

movement on expiration (chest sucks in when person breathes in)

• r

Use

• f

accessory muscles of neck or intercostal muscles or 'tracheal tug' during inspiration

• r

Subcostal recession t abdominal breathing')

t t

breaths/min Adults: ~

beats/min Children: tachycardia

t

90-94% Not indicated Life-threatening (any of): Can't speak Collapsed or exhausted Severe respiratory distress

• r

Poor respiratory effort Drowsy

• r

unconscious Cyanosis Bradypnoea (indicates respiratory exhaustion) Cardiac arrhythmia

• r

Bradycardia (may

• ccur

just before respiratory arrest) Silent chest

• r

Reduced air entry <90%

• r

Clinical cyanosis PaO, <60 mmHg PaC07 >50 mmHg§ PaC07within 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

• ne 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,

• xygen 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

• xygen 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 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 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 first hour

OR

Give 500 meg nebule via nebuliser added to nebulised salbutamol every 20 minutes for first 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~
• r

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

• f

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

• ver: 4-12

puffs 0 -5 years: 2-6 puffs

REASSESS SEVERITY

Any of: unable to speak in sentences, visibly breathless, increased work of breathing,

• xygen 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

• xygen

6 year s and over: use 2 x 5 mg nebules 0 - 5 years: use 2 x 25 mg nebules Start

• xygen If
• xygen saturation

less than 95% Titrate

to

• xygen saturation
• f

at

least 95% Table V. Secondary severity assessm ent

• f

acute asthma in adults and children 6 yea rs and

• ver

Table W . Secondary severity assessm ent

• f

acute asthma 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 to 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) via pMDI (21 meg/actuation) every 20 minutes

for first hour. OR Give via nebuliser added to nebulised salbutamol

6 years and over: 500 meg nebule 0 -5 years: 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

• ral route

not possible Hydrocortisone IV initial dose 8 - 10

mg./kg (max 300 mg). then 4 - 5 rngl\<g/dose every 6 hours

• n 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

• n day 1, then every 12 hours
• n

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

• 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

• ne hour

Breathing difficulty persists

L

Persisting

• r

life-threatening acute asthma Transfer to ICU or discuss transfer/retrieval with senior medical staff

• drowsy
• poor respiratory

• collapsed
• soft/absent breath

• exha usted
• oxygen saturation <90"
• cyanotic

• xycen to

• xvaen

. e

mcs ipratropium bromide

mcs iprotropium bromide

• ver:O.l-0.2 mmollkg MgS0

• Symptoms resolved

• f

• ver: 12 puffs solbutamol

• r

• Adults and

• ver: 5 mg nebule ~

• CONTINUE SALBUTAMOL BY CONTINUOUS

• f

.f.\. Monitor blood electrolytes.

Lll

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

Author Year Location Patient numbers neb: iv Age Weight Attack duration before treatment Salbutamol nebulisation Assumed 10 min salbutamol iv, if 70kg Total IV salbutamol

• ver time

Result Side effects Blood levels salbutamol ng.ml‐1 Lawford 1978 Single centre

7:7 15‐65yrs No weight Not stated 10mg in 10ml saline

• ver 45 min

200mcg 900mcg over 45 min IV and nebulised groups improved iv = pulse rise, shaking, ectopics None

Cheong 1982 Single centre

34:37 16‐69yrs No weight ½ hr? unclear 5mg at 0, 30 and 120

• min. No time of neb

duration 125mcg 3000mcg Over 4 hours IV more effective Tachycardia in iv group at 3.5hr P<0.001 None

Swedish Society 1990 13 centres

87:89 55 (13) Weight recorded but not used for iv Not stated 5mg over 7min x2 at 0 and 30min delivery by IPPB on inhalation 350mcg 350mcg

• ver 10 min

Neb better than iv Tachycardia in neb group at 120 min P<0.001 Yes. Pre:post neb 7.1+/‐7 :16+/‐9 Iv 5.7+/‐6 :6.6+/‐6.4 P<0.001

Salmeron 1994 4 centres

22:25 39 +/‐13yrs No weight 14 +/‐ 16 hrs 5mg over 15min x2 during 60 min 83 mcg 500mcg

• ver 60 min

Neb better No difference NS Yes. Pre:post neb 2.9:7.8 iv 3.6:10 Non significant

Browne 1997 Single centre

15:14 8.4 (3.1)yrs 29.2 (10.1)kg Children 1 hr? unclear 2.5 or 5mg in 4ml saline. No time of nebulisation 1050 mcg For a 70kg equivalent adult 438 mcg For average 29.2kg child over 10 min IV better. 9.7hr earlier discharge from ED Greater tremor in iv P<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 Patients Age yrs Presentation Co‐morbidity DoseIV MgSO4 Delivery speed Result Side effects Other drugs Mg level Iseri/1985

10 52‐76 Atrial tachycardia COPDx7, CHF 2g Infusion 60 sec Rate down Not stated Theophylline in 6 yes

Pritchard/1984

245 Pregnant Eclampsia 4g 4 min then im One fatality 20g iv in error One blood level

Dicarlo/1986

10 54+/‐12 Tests Cardiomyopathy X6 6g Infusion 6 min Increase PR, AV refractory A‐H interval Warmth, flushing yes

Wesley/1989

10 20‐71 SVT inducedx5 1x CAD 1x SSS 2g 5 sec Slowed SVT X4 ventric triplet Verapamil, digoxin, terbutaline, atropine yes

Viskin/1992 Mag vs Adenosine

14 SVT Mitral valve disease. A‐H= Atrial His interval 2g 15 sec Chest pain, flushing, nausea

Hays/1994

7 67+/‐16 New AF MVD High 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 Salbutamol First 10 mins Next 50mins Next 1 hr Total over 2 hr 3.5 mg 17.5 mg 4.2 mg 25.2 mg 1.05 mg 17.5 mg 21.0 mg 39.6 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
• ther cannula free
• Give a fluid bolus ~

repeated.

ACI

• 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

• 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 Mg NIPPV 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