Acute Asthma Exacerbation: Management in the ED Patrick PLAISANCE, M.D., PhD. Associate Professor...
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Transcript of Acute Asthma Exacerbation: Management in the ED Patrick PLAISANCE, M.D., PhD. Associate Professor...
Acute Asthma Acute Asthma Exacerbation: Exacerbation:
Management in the EDManagement in the EDPatrick PLAISANCE, M.D., PhD.Patrick PLAISANCE, M.D., PhD.
Associate ProfessorAssociate Professor
Department of Anesthesia, MGH, MUHC.Department of Anesthesia, MGH, MUHC.
NIH DefinitionNIH Definition Chronic inflammatory changes in the Chronic inflammatory changes in the
bronchial submucosabronchial submucosa
Increased responsiveness of the airwaysIncreased responsiveness of the airways
Reversible expiratory airway obstructionReversible expiratory airway obstruction
Ventilatory :Ventilatory : dynamic resistances dynamic resistances
residual volumeresidual volume
AtelectasesAtelectases
V/P mismatchingV/P mismatching
Airways dynamic collapseAirways dynamic collapse
Hemodynamic :Hemodynamic : Paradoxical pulse > 18 mmHgParadoxical pulse > 18 mmHg
Ventilatory and Ventilatory and Hemodynamic Hemodynamic ConsequencesConsequences
Triggering FactorsTriggering Factors• Infection:
– Bacterial sinusitis– Tracheo-bronchial infection– Viral infection of the airways
• Medications:– Beta blockers (collyrium), aspirine, NSAI, antibiotics
• Others:– Gastro-oesophageal reflux– Psycho-sociological factors – Stress– Exercise – Stop of chronic treatment
Bad Prognosis FactorsBad Prognosis Factors
• Previous severe exacerbations
• Hospitalization within the last year
• Psycho-sociological factors
• Previous intubations
• Stop of corticosteroid treatment
• Low patient’s compliance
Importance of an Early Treatment
Inhalation versus IV Infusion in Mild Exacerbations
Inhalation versus IV Infusion in Severe Exacerbations
Efficacy of the Inhaled Efficacy of the Inhaled RouteRoute
- nebulizer- nebulizer- gas flow- gas flow- driving gas- driving gas
Advantages of the Inhaled Advantages of the Inhaled RouteRoute
• Direct respiratory tropism• Short onset of action• Low doses• Less side-effects
• Simultaneous O2 delivery
• Humidification of the airways
Intermittent versus Intermittent versus Continuous NebulizationContinuous Nebulization
• Small benefit from continuous nebulization– Gibbs et al. Acad Emerg Med, 2000
• Beneficial effect on severe exacerbations• No increased side-effects
– Moler et al. Am J Respir Crit Care Med, 1995
• Reduction of staff time– Fink et al. Respir Care 2000
Guidelines on Nebulizer Guidelines on Nebulizer TherapyTherapy
(British Thoracic Society, (British Thoracic Society, ThoraxThorax 1997) 1997)
• Driving gas (SpO2 > 90%):
– Air + simultaneous O2 (nasal prong)
– O2
• Fill volume of 4 mL (if residual volume > 1 mL)
• Flow rate 6-8 L/min• Nebulization time < 10 min
Meter-Dose InhalersMeter-Dose Inhalerswith Holding Chamberswith Holding Chambers
• As effective as nebulizers (Cates et al. Cochrane Database Syst Rev, 2000)– Similar hospital admission rate– Similar improvement in PEFR and FEV1– Children:
HR more important duration of the treatment in the ED
• Progressive administration of the medication
• Interesting for children < 3 years
22+ Mechanism of Action+ Mechanism of Action
muco-ciliary clearence
vascular permeability
• Inhibition of transmitter release from mast cells
22 Agonists Agonists
• Selective (Terbutaline, Salbutamol)– First line therapy– Short onset of action (2-5 min)– Long duration of action (3-6 h)– Different routes of administration
• Non selective (epinephrine)– Vasoconstricting agent– Short duration of action– Side effects
AnticholinergicsAnticholinergicsMechanism of ActionMechanism of Action
• Ach competitive inhibitors
• muscarinic receptors antagonists
• Bronchodilators
• Inhibitors of the bronchoconstriction induced by irritant agents
Anticholinergics + Anticholinergics + 22 AgonistsAgonistsChildrenChildren
• Schuh S et al. Pediatr 1995:– N = 120– 5-17 y.o. FEV1, PEFR, hospitalization stay:
•Salbutamol < salbutamol + 1 ipratropium < Salbutamol + 3 ipratropium
•More interesting in severe exacerbations
Anticholinergics + Anticholinergics + 22 + +Meta-analyses ChildrenMeta-analyses Children
• Plotnick LH et al. Cochrane Database Syst Rev 2000– N = 836 children– Spirometric improvement Hospital admission rates
Anticholinergics + Anticholinergics + 22 AgonistsAgonists
Meta-analyses AdultsMeta-analyses Adults• Rodrigo et al. Am J Med 1999
– n = 1483– Randomized studies, double-blind, controlled– Results:
• Pulmonary function improvement Hospital admission
• Stoodley et al. Ann Emerg Med 1999– N = 1377– Slight clinical improvement– No side-effects
Anticholinergics and Anticholinergics and 22+ in Adults+ in Adults
Groups Groups PEFR (L/min) PEFR (L/min) PEFR (L/min) PEFR (L/min) PEFR (L/min) PEFR (L/min) HospitalHospital
T12hT12h T36h T36h T60h stay (d) T60h stay (d)______________________________________________________________________________________________________________S + IB 12hS + IB 12h 68 68 62 62 56 56 5,4* 5,4*
S + IB 36hS + IB 36h 81 81 73 73 47 47 4,1 4,1
S + IB 60hS + IB 60h 100100 69 69 42 42 4 4
* p < 0,01* p < 0,01
Brophy C et al. Brophy C et al. ThoraxThorax 1998 1998
CorticosteroidsCorticosteroids hospital admission if administered within the 1st hour
• Equal benefit of orally and IV administration– Rowe et al. Cochrane Database Syst Rev, 2000
• Dose ranging from 30-400 mg methylprednisolone :– Manser et al. Cochrane Database Syst Rev, 2000
• Inhaled vs systemic corticosteroids: (Edmonds et al. Cochrane Database Syst Rev. 2003) PEFR and FEV1 as compared with placebo
– as effective as systemic corticosteroids ?
– Combination better than systemic route alone ?
MethylxanthinesMethylxanthines
• No benefit from adding methylxanthines
to 2+
• More adverse effects– Parameswaran et al. Cochrane Database Syst Rev
2000
MgSOMgSO44
• Inhalation:– Improvement in clinical score (Fischl), PEFR, PP– Nannini LJJr. Am J Med 2000– Mangat HS Eur Respir J 1998
PEFR
• IV:– Boonyavorakul C. Respiratology 2000
• Hospital admission = NS; score = NS
– Rowe BH. Ann Emerg Med 2000 admission rate in severe asthma exacerbations
Helium PropertiesHelium Properties
• Inert gas, colourless, odourlessInert gas, colourless, odourless
• Density lower than air and ODensity lower than air and O22
• No diffusion through cellular membranes No diffusion through cellular membranes
• No chemical and physiological actionNo chemical and physiological action
• Action due to its physical propertiesAction due to its physical properties
No bronchodilator and anti-inflammatory actionNo bronchodilator and anti-inflammatory action
Barach et al. Ann Int Med 1935Barach et al. Ann Int Med 1935
• The use of Helium in the Treatment of The use of Helium in the Treatment of Asthma and Obstructive Lesions in the Asthma and Obstructive Lesions in the Larynx and Trachea Larynx and Trachea
StudiesStudies
• Small trials or case reports with poor methodology
• Evaluation criteria varying from one study to another
• Different treatment duration
Importance of Flow RateImportance of Flow Rate
. Continuous nebulization. Continuous nebulization
. P1 = 3,5 bars. P1 = 3,5 bars
Gas flowGas flow Q = 8 L/min Q = 12.7 L/min Q = 8 L/min Q = 8 L/min Q = 12.7 L/min Q = 8 L/min He/OHe/O22 He/ O He/ O22 O O22
__________________________________________________________________________________________________________________________P2 (bars)P2 (bars) 0.64 0.64 1.411.41 1.451.45
MMAD (mm)MMAD (mm) 5.365.36 3.183.18 3.603.60
Nebulized massNebulized massafter 10 ’ (g)after 10 ’ (g) 2.252.25 3.353.35 2,.852,.85
Nebulized massNebulized massafter 15 ’ (g)after 15 ’ (g) 3.353.35 4.084.08 3.693.69
Nebulized massNebulized massafter 20 ’ (g)after 20 ’ (g) 3.833.83 4.464.46 4.064.06
PEFR
100120
150
250
190
290
192
330
0
50
100
150
200
250
300
350
T0 T20 T40 T60
O2He-O2
*
**
*p < 0,01*p < 0,01
L/min
O2 HeO2 p
Transfer to ICU (%) 62,89% 52% nsMean duration of stay in ICU 4,1 ± 5,4 2,1± 2,6 nsPatient still in ICU at Day 4 19 8 0,02Intubation rate 7,37% 1% 0,03
Within the last 3 monthsASUR2001
30 %
38 %
23 %
8 %
0%
5%
10%
15%
20%
25%
30%
no(n = 1237)
General Practitioner (n =1555)
Pneumologist (n = 962)
Both(n =333)
Patients having a peak flow at home : 16 % (n = 652)
Salmeron et al. Asthma severity and adequacy of management in accident and emergency departments in France : a prospective study. The Lancet ; 2001 ; 358 : 629 – 35.
4 087 asthma exacerbations
Severity Upon ArrivalASUR2001
Mild to moderate exacerbation
(PEFR > 50%)
Salmeron S, et al. Asthma severity and adequacy of management in accident and emergency departments in France : a prospective study. The Lancet ; 2001 ; 358 : 629 – 35.
26 %(n = 975) 49 %
(n = 1834)
25 %(n = 963)
Fatal asthma
(PEFR < 30%) Severe exacerbation
(30 % PEFR 50 %)
• age• gender• recent corticosteroid treatment per os• hospitalization within the last year
The severity of exacerbation is independent of :
Treatment in the EDASUR2001
Salmeron S, et al. Asthma severity and adequacy of management in accident and emergency departments in France : a prospective study. The Lancet ; 2001 ; 358 : 629 – 35.
95 % (n = 924)
0
10 %
20 %
30 %
40 %
50 %
60 %
70 %
80 %
90 %
93 % (n = 1708) 89 %
(n = 860)
51 %(n = 494)
50 %(n = 913) 45 %
(n = 434)
68 %(n = 666) 61 %
(n = 1117)49 %
(n = 468)
Inhaled 2 agonists
Inhaledanticholinergiques
Systemic corticosteroids
Mild to moderate exacerbation
Fatal asthma
Severe exacerbation
• inhaled 2 agonists : 92 % (n = 3492)• inhaled anticholinergics : 49 % (n = 1841)• systemic corticosteroids : 60 % (n = 2251)
Pre-Determined Management Pre-Determined Management PlanPlan
• McFadden et al. McFadden et al. Am J MedAm J Med 1995 1995– Length of stay in the ERLength of stay in the ER
– Admission ratesAdmission rates
– Re-admissionRe-admission
– Cost savingsCost savings
Initial MonitoringInitial Monitoring
• Pulse oxymetryPulse oxymetry
• PEFR (best of three)PEFR (best of three)
• Pulse, BPPulse, BP
• RRRR
• Clinical judgement:Clinical judgement:– CyanosisCyanosis
– Use of accessory musclesUse of accessory muscles
– StridorStridor
– diaphoresisdiaphoresis
• Blood gassesBlood gasses
Initial Treatment in ChildrenInitial Treatment in Children
Inhaled Treatment Inhaled Treatment Associated Associated
TreatmentTreatment
every 20’ within the 1st hourevery 20’ within the 1st hour
. O. O22 6-8 L/min (SpO 6-8 L/min (SpO22 95%) 95%) . Salbutamol or . Salbutamol or
TerbutalineTerbutaline
. Salbutamol 0.5%: 0.03 mL/kg or 7-10 . Salbutamol 0.5%: 0.03 mL/kg or 7-10 g/kg SCg/kg SC
Terbutaline 5 mg + IB 0.25 mgTerbutaline 5 mg + IB 0.25 mg . HSHC 5 mg/kg or . HSHC 5 mg/kg or
methyl-methyl-
. Or 0.2-0.3 puffs/kg with MDI . Or 0.2-0.3 puffs/kg with MDI prednisolone 2 mg/kg prednisolone 2 mg/kg
IVDIVD
+ HC+ HC
Initial Treatment in AdultsInitial Treatment in Adults
Inhaled Treatment Inhaled Treatment Associated Treatment Associated Treatment
every 20 min within the 1st hourevery 20 min within the 1st hour
. O. O22 6-8 L/min (SpO 6-8 L/min (SpO22 90%) 90%) . Salbutamol or . Salbutamol or
TerbutalineTerbutaline
. Salbutamol 2.5 mg (or 7.5 mg (0.5 mg) or . Salbutamol 2.5 mg (or 7.5 mg (0.5 mg) or
epinephrine epinephrine
continuously) + IB 0.5 mg continuously) + IB 0.5 mg 0.25 mg SC 0.25 mg SC
. or 2-3 puffs with MDI + HC . HSHC 200-400 mg or. or 2-3 puffs with MDI + HC . HSHC 200-400 mg or
. or epinephrine 2 mg + 3 mL NS methyl-prednisolone 1 . or epinephrine 2 mg + 3 mL NS methyl-prednisolone 1
mg/kg mg/kg IV IV
Inhospital TreatmentInhospital Treatment
Initial treatmentInitial treatment
Improvement (PEFR: 50-70%)Improvement (PEFR: 50-70%)No improvement (PEFR < 50%)No improvement (PEFR < 50%)
Good responseGood responseresponse>1hresponse>1hExamination nlExamination nlPEFR > 70%PEFR > 70%
Incomplete ResponseIncomplete Response. Moderate signs. Moderate signs. PEFR: 50-70%. PEFR: 50-70%
No improvementNo improvement. Severe signs. Severe signs. PEFR < 30%. PEFR < 30%. PaCO. PaCO22 > 45 mmHg > 45 mmHg. PaO. PaO22 < 60 mmHg < 60 mmHg
DischargeDischarge
Admission Admission ICUICU
22+: 1/h for 1-3 h+: 1/h for 1-3 h 22+ + IB: 3/h pdt 1-3 h+ + IB: 3/h pdt 1-3 h22 IV IV
PEFR > 70%PEFR > 70%Examination nlExamination nl12h with no tt12h with no tt
No improvement No improvement within 6-12hwithin 6-12h
AntibioticsAntibiotics
• Graham et al. Cochrane Database Syst Rev. 2001– No benefit when comparing antibiotics to placebo
• Indications: GOLD-guideline (Pauwels et al. Respir Care 2001)– Worsening dyspnea and cough– Increased sputum volume and purulence– Infiltrates on the chest X-ray
NIVNIV
• VS-PEP (Shivaran U et al. Resp 1987) residual volume respiratory work– Risks:
• Overdistension of zones with low resistance• Pulmonary hyperinflation
ConclusionConclusion
• Importance of an early treatment Importance of an early treatment
• Importance of nebulizationImportance of nebulization
• Combination Combination 22 agonists/Ipratropium Bromide agonists/Ipratropium Bromide
• Combination of different routesCombination of different routes
• PEFR monitoringPEFR monitoring
• Interest of MgSOInterest of MgSO44 and Helium ? and Helium ?