Difference between revisions of "Acute asthma exacerbation (peds)"

(Steroids)
(Evaluation)
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*A history of eczema or allergies maybe helpful in making a new diagnosis of asthma
 
*A history of eczema or allergies maybe helpful in making a new diagnosis of asthma
 
*Wheezing in an infant is more often [[bronchiolitis]] than asthma  
 
*Wheezing in an infant is more often [[bronchiolitis]] than asthma  
*Viral [[URI]], allergen exposure, and respiratory irritants (i.e. smoke) are common precipitants for pediatric asthma exacerbations
+
*Viral [[URI]] associated with copious rhinorrea, allergen exposure, and respiratory irritants (i.e. smoke) are common precipitants for pediatric asthma exacerbations
  
 
==Clinical Features==
 
==Clinical Features==
*Wheezing
+
*[[Wheezing]]
 
*[[Cough]]
 
*[[Cough]]
 
*Accessory muscle use
 
*Accessory muscle use
 
*[[Dyspnea]]
 
*[[Dyspnea]]
 
*Prolonged expiration
 
*Prolonged expiration
 +
*Severity of retractions occurs in caudal to cephalad direction
 +
**Scalene muscle contractions more severe than subcostal and intercostal retractions
 
*Sign of impending ventilatory failure
 
*Sign of impending ventilatory failure
 
**Paradoxical respiration
 
**Paradoxical respiration
Line 25: Line 27:
 
==Evaluation==
 
==Evaluation==
 
*Clinical diagnosis
 
*Clinical diagnosis
 +
*Can consider a blood gas if there are fears that the patient is getting tired (sleepy baby vs [[hypercapnia|elevated CO2]]?)
 +
**A CO2 >45 is abnormal in a patient hyperventilating and warrants close monitoring
  
 
===Consider [[CXR]]===
 
===Consider [[CXR]]===
Line 31: Line 35:
 
*Poor response to medications/treatment, if history and exam are not consistent with [[bronchiolitis]]
 
*Poor response to medications/treatment, if history and exam are not consistent with [[bronchiolitis]]
 
*Worsening symptoms
 
*Worsening symptoms
 +
*Fever not explained by apparent viral illness
  
 
===Clinical Scores===
 
===Clinical Scores===
Line 45: Line 50:
 
''Favor continuous nebulization to decrease the chance of admission when compared to intermittent dosing''<ref>Camargo CA et al. Continuous versus intermittent beta- agonists for acute asthma. Cochrane Database Syst Rev. 2003;(4):CD001115. PMID: 14583926.</ref>
 
''Favor continuous nebulization to decrease the chance of admission when compared to intermittent dosing''<ref>Camargo CA et al. Continuous versus intermittent beta- agonists for acute asthma. Cochrane Database Syst Rev. 2003;(4):CD001115. PMID: 14583926.</ref>
 
*Nebulizer
 
*Nebulizer
**Intermitent: 2.5-5mg q20min, three doses are tradionally given back to back, then repeat as needed.
+
**Intermittent: 2.5-5mg q20min, three doses are traditionally given back to back, then repeat as needed.
 
**Continuous: 0.5mg/kg/hr (max 15mg/hr)<ref>National Asthma Education and Prevention Program (NAEPP), “Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma,” Clinical Practice Guidelines, National Institutes of Health, National Heart, Lung, and Blood Institute, NIH Publication No. 08-4051, prepublication 2007; available at http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm.</ref>
 
**Continuous: 0.5mg/kg/hr (max 15mg/hr)<ref>National Asthma Education and Prevention Program (NAEPP), “Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma,” Clinical Practice Guidelines, National Institutes of Health, National Heart, Lung, and Blood Institute, NIH Publication No. 08-4051, prepublication 2007; available at http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm.</ref>
 
*MDI
 
*MDI
Line 51: Line 56:
  
 
===[[Ipratropium]]===
 
===[[Ipratropium]]===
*0.5mg q20min, given with the first three doses of albuterol, it is shown to reduce admission.
+
*0.25-0.5mg q20min, given with the first three doses of albuterol, it is shown to reduce admission.
 
===[[Steroids]]===
 
===[[Steroids]]===
 
''Should be given in the first hour with effects to reduce admission<ref name="Rowe">Rowe BH et al. Magnesium sulfate for treating exac- erbations of acute asthma in the emergency depart- ment. Cochrane Database Syst Rev. 2000;(2):CD001490. PMID: 10796650.</ref>''
 
''Should be given in the first hour with effects to reduce admission<ref name="Rowe">Rowe BH et al. Magnesium sulfate for treating exac- erbations of acute asthma in the emergency depart- ment. Cochrane Database Syst Rev. 2000;(2):CD001490. PMID: 10796650.</ref>''
 
*[[Dexamethasone]]
 
*[[Dexamethasone]]
**0.6mg/kg PO or IV (max 16mg); 2nd dose 24-36hrs later.  
+
**0.6mg/kg PO or IV (max 16mg); consider 2nd dose 24-36hrs later.  
***PO and IV have equal efficacy  
+
***PO and IV have equal efficacy. Giving the IV form by mouth is typically better tolerated by young children (same dosing)
**Both 1 and 2 dose regimens as effective as prednisone in children <ref>Keeney, et al. Dexamethasone for Acute Asthma Exacerbations in Children: A Meta-analysis. Pediatrics. 2013-2273</ref>
+
**Both 1 and 2 dose regimens as effective as [[prednisone]] or [[prednisolone]] in children <ref>Keeney, et al. Dexamethasone for Acute Asthma Exacerbations in Children: A Meta-analysis. Pediatrics. 2013-2273</ref><ref>Cronin et al. "A Randomized Trial of Single-Dose Oral Dexamethasone Versus Multidose Prednisolone for Acute Exacerbations of Asthma in Children Who Attend the Emergency Department." Annals of EM. May 2016. 67(5):593-601</ref>
 
*[[Prednisone]]
 
*[[Prednisone]]
**1-2mg/kg/day(60mg max) in one or two divided doses for 3-5 days
+
**1-2mg/kg/day (60mg max) in one or two divided doses for 3-5 days
 
*[[Methylprednisolone]]
 
*[[Methylprednisolone]]
 
**1mg/kg IV q 4–6hr
 
**1mg/kg IV q 4–6hr
Line 65: Line 70:
  
 
===[[Magnesium]]===
 
===[[Magnesium]]===
*Dose: 50mg/kg IV, max 2-4 g
+
*Dose: 50mg/kg IV, max 2-4 g over 20 mins with close blood pressure monitoring
 
*Smooth muscle relaxant
 
*Smooth muscle relaxant
*Duration of action approx 20 min
+
*Duration of action approximately 20 min
 
*In patients with moderate to severe asthma there is a decreased rate of admission with an NNT of 2<ref name="Rowe"></ref>
 
*In patients with moderate to severe asthma there is a decreased rate of admission with an NNT of 2<ref name="Rowe"></ref>
  
Line 82: Line 87:
 
**Alleviates muscle fatigue which leads to larger tidal volumes
 
**Alleviates muscle fatigue which leads to larger tidal volumes
 
**Maximize inspiratory support
 
**Maximize inspiratory support
***Inspiratory pressure 10
+
***Delta pressure 10
***PEEP 0-5
+
***PEEP >4
 
+
**May benefit from [[ketamine]] or [[dexmedetomidine]] to mildly sedate and allow the interface
*Heliox
 
**60 to 80% helium is blended with 20 to 40% oxygen
 
**Heliox improves non laminar flow and may increases the diffusion of carbon dioxide by improving ventilation<ref>Kass JE: Heliox redux. Chest 2003; 123:673.</ref>
 
  
 
===[[Intubation]]===
 
===[[Intubation]]===
*Consider induction with [[Ketamine]]
+
*Push pull (bolus) [[IVF|fluids]] prior to intubation to maximize the patient's preload and ideally decrease the chance of the patient arresting
 +
*Consider induction with [[ketamine]]
 
**Provides bronchodilation and sedation however it does promote secretions  
 
**Provides bronchodilation and sedation however it does promote secretions  
 
**Ketamine is the preferred induction agent for intubation in an asthmatic.  
 
**Ketamine is the preferred induction agent for intubation in an asthmatic.  
**Dosing 1-2mg/kg
+
**Dosing 1-2 mg/kg
 
*Ventilation of asthmatic patients requires deep sedation
 
*Ventilation of asthmatic patients requires deep sedation
**[[Benzos]], [[propfol]], or [[ketamine]] (1mg/kg/hr)
+
**[[Benzos]], [[ketamine]] (1 mg/kg/hr)
 
*[[Ventilation settings]]
 
*[[Ventilation settings]]
 
**Assist-control ventilation
 
**Assist-control ventilation
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***Start slow to avoid air-trapping and allow for longer expiration time
 
***Start slow to avoid air-trapping and allow for longer expiration time
 
***Consider I:E ratio of 1:2 or 1:3
 
***Consider I:E ratio of 1:2 or 1:3
**Make sure plateau pressure <30
+
**Plateau pressure ideally <30
 
**May require "permissive hypoventilation" and permissive hypercarbia and acidosis
 
**May require "permissive hypoventilation" and permissive hypercarbia and acidosis
 
***Low peak pressure/avoidance of breath stacking more important than correcting CO2 <ref> Darioli, et al. Mechanical Controlled hypoventilation in status asthmaticus. Am Rev Respir Dis. 1984; 129 (3) 385-7 </ref>
 
***Low peak pressure/avoidance of breath stacking more important than correcting CO2 <ref> Darioli, et al. Mechanical Controlled hypoventilation in status asthmaticus. Am Rev Respir Dis. 1984; 129 (3) 385-7 </ref>
 
**Tidal volume 6-8cc/kg ideal wt
 
**Tidal volume 6-8cc/kg ideal wt
**PEEP 0-5
+
**PEEP >4
 
**Flow rate 80-100L/min
 
**Flow rate 80-100L/min
 
**Keep FiO2 minimum to achieve SpO2 > 90%
 
**Keep FiO2 minimum to achieve SpO2 > 90%
 
*Use bronchodilators even when intubated
 
*Use bronchodilators even when intubated
 +
*Many patients require a continuous [[neuromuscular blocking agents|paralytic]] infusion for the first 24+ hrs of intubation
  
 
==Outpatient Treatment==
 
==Outpatient Treatment==
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| align="center" style="background:*f0f0f0;"|'''Treatment (WHO 2008 Formulary)<ref>Stuart MC et al. WHO Model Formulary 2008. http://www.who.int/selection_medicines/list/WMF2008.pdf.</ref>'''
 
| align="center" style="background:*f0f0f0;"|'''Treatment (WHO 2008 Formulary)<ref>Stuart MC et al. WHO Model Formulary 2008. http://www.who.int/selection_medicines/list/WMF2008.pdf.</ref>'''
 
|-
 
|-
| Mild intermittent, > 80% peak flow||< 2/wk||< 2/mo||[[Albuterol]] MDI 100-200 mcg prn qid
+
| Mild intermittent, > 80% peak flow||< 2/wk||< 2/mo||[[Albuterol]] MDI 100-200 mcg PRN QID
 
|-
 
|-
| Mild persistent, > 80% peak flow||>2/wk||>2/mo||[[Albuterol]] MDI 100-200 mcg prn qid
+
| Mild persistent, > 80% peak flow||>2/wk||>2/mo||[[Albuterol]] MDI 100-200 mcg PRN QID '''AND'''
PLUS
+
[[Beclometasone]] 100-250 mcg BID
[[Beclometasone]] 100-250 mcg bid
 
 
|-
 
|-
| Moderate persistent, 60-80% peak flow||Daily with exacerbations weekly||> 1/wk||[[Albuterol]] MDI 100-200 mcg prn qid
+
| Moderate persistent, 60-80% peak flow||Daily with exacerbations weekly||> 1/wk||[[Albuterol]] MDI 100-200 mcg PRN QID '''AND'''
PLUS
+
[[Beclometasone]] 100-500 mcg BID '''AND'''
[[Beclometasone]] 100-500 mcg bid
 
  
PLUS
+
[[Salmeterol]] inhaled 50 mcg BID
[[Salmeterol]] inhaled 50 mcg bid
 
 
|-
 
|-
| Severe persistent, < 60% peak flow||Continuous daily||Frequent||[[Albuterol]] MDI 100-200 mcg prn qid
+
| Severe persistent, < 60% peak flow||Continuous daily||Frequent||[[Albuterol]] MDI 100-200 mcg PRN QID '''AND'''
PLUS
+
[[Beclometasone]] 1mg BID (high dose) '''AND'''
[[Beclometasone]] 1mg bid (high dose)
 
  
PLUS
+
[[Salmeterol]] inhaled 50 mcg BID '''AND'''
[[Salmeterol]] inhaled 50 mcg bid
 
  
PLUS (if needed)
+
[[theophylline]], leukotriene antagonist, or PO [[prednisolone]] with taper
SR [[theophylline]], leukotriene antagonist, or PO [[prednisolone]] with taper
 
 
|}
 
|}
  
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*'''Discharge'''  
 
*'''Discharge'''  
 
**Often, patients will still have mild wheezing, but should have complete resolution of tachypnea, hypoxia, and improved work of breathing  
 
**Often, patients will still have mild wheezing, but should have complete resolution of tachypnea, hypoxia, and improved work of breathing  
**A short course of glucocorticoids decreases chance of relapse <ref>Chapman K. Effect of a short course of prednisone in the prevention of early relapse after the emergency room treatment of acute asthma. NEJM. 1991;324(12):788</ref>)
+
**A short course of glucocorticoids decreases chance of relapse <ref>Chapman K. Effect of a short course of [[prednisone]] in the prevention of early relapse after the emergency room treatment of acute asthma. NEJM. 1991;324(12):788</ref>)
 
**Patient should generally continue albuterol at home q6hrs for at least the first 24hrs after discharge
 
**Patient should generally continue albuterol at home q6hrs for at least the first 24hrs after discharge
 
**A spacer should be prescribed to be used with the MDI to improve medication delivery to the lungs
 
**A spacer should be prescribed to be used with the MDI to improve medication delivery to the lungs
Line 156: Line 154:
  
 
==See Also==
 
==See Also==
 +
*[[Asthma]]
 +
*[[Modified pulmonary index score]]
 
*[[Ventilation settings]]
 
*[[Ventilation settings]]
 
*[[Deterioration after intubation]]
 
*[[Deterioration after intubation]]
 
*[[Shortness of breath]]
 
*[[Shortness of breath]]
*[[Asthma]]
 
  
 
==External Links==
 
==External Links==

Revision as of 15:22, 11 October 2019

For adult patients see Asthma

Background

  • An estimated 6 million children in the US have asthma
  • In 2007, asthma lead to >700,000 ED visits
  • Asthma is part of the atopy triad (asthma, allergies, eczema)
  • A history of eczema or allergies maybe helpful in making a new diagnosis of asthma
  • Wheezing in an infant is more often bronchiolitis than asthma
  • Viral URI associated with copious rhinorrea, allergen exposure, and respiratory irritants (i.e. smoke) are common precipitants for pediatric asthma exacerbations

Clinical Features

  • Wheezing
  • Cough
  • Accessory muscle use
  • Dyspnea
  • Prolonged expiration
  • Severity of retractions occurs in caudal to cephalad direction
    • Scalene muscle contractions more severe than subcostal and intercostal retractions
  • Sign of impending ventilatory failure
    • Paradoxical respiration
      • Chest deflation and abdominal protrusion during inspiration
    • Altered mental status
    • "Silent chest"

Differential Diagnosis

Pediatric Wheezing

Evaluation

  • Clinical diagnosis
  • Can consider a blood gas if there are fears that the patient is getting tired (sleepy baby vs elevated CO2?)
    • A CO2 >45 is abnormal in a patient hyperventilating and warrants close monitoring

Consider CXR

  • 1st wheezing episode
  • Asymmetric lung auscultation findings, after treatment with albuterol
  • Poor response to medications/treatment, if history and exam are not consistent with bronchiolitis
  • Worsening symptoms
  • Fever not explained by apparent viral illness

Clinical Scores

  • Diagnosis and treatment can be guided by clinical scores
    • Modified Pulmonary Index Score (MPIS - Utilized at CCMC)
    • Pediatric Asthma Score (PAS)
    • Pulmonary Score (PS)
    • Pediatric Respiratory Assessment Measure (PRAM)

Modified Pulmonary Index Score (MPIS)

Age <3 Years
Points SpO2 Acces Musc Use I:E Wheeze HR RR
0 >95% None 2:1 None; Good Aeration ≤120 ≤30
1 93-95% Mild 1:1 End Exp 121-140 31-45
2 90-92% Moderate 1:2 Insp/Exp; Good Aeration 141-160 46-60
3 <90% Severe 1:3 Insp/Exp; Poor Aeration >160 >60
Age 3-6 Years
Points SpO2 Acces Musc Use I:E Wheeze HR RR
0 >95% None 2:1 None; Good Aeration ≤100 ≤30
1 93-95% Mild 1:1 End Exp 101-120 31-45
2 90-92% Moderate 1:2 Insp/Exp; Good Aeration 121-140 46-60
3 <90% Severe 1:3 Insp/Exp; Poor Aeration >140 >60
Age ≥6 Years
Points SpO2 Acces Musc Use I:E Wheeze HR RR
0 >95% None 2:1 None; Good Aeration ≤100 ≤20
1 93-95% Mild 1:1 End Exp 101-120 21-35
2 90-92% Moderate 1:2 Insp/Exp; Good Aeration 121-140 36-50
3 <90% Severe 1:3 Insp/Exp; Poor Aeration >140 >50
  • MPIS <7 - Mild exacerbation
  • MPIS 7-10 - Moderate exacerbation
  • MPIS ≥10 - Severe exacerbation

Management

Albuterol

Favor continuous nebulization to decrease the chance of admission when compared to intermittent dosing[1]

  • Nebulizer
    • Intermittent: 2.5-5mg q20min, three doses are traditionally given back to back, then repeat as needed.
    • Continuous: 0.5mg/kg/hr (max 15mg/hr)[2]
  • MDI
    • 4-8 puffs q20min given in first hour, then q1-4hr as needed

Ipratropium

  • 0.25-0.5mg q20min, given with the first three doses of albuterol, it is shown to reduce admission.

Steroids

Should be given in the first hour with effects to reduce admission[3]

  • Dexamethasone
    • 0.6mg/kg PO or IV (max 16mg); consider 2nd dose 24-36hrs later.
      • PO and IV have equal efficacy. Giving the IV form by mouth is typically better tolerated by young children (same dosing)
    • Both 1 and 2 dose regimens as effective as prednisone or prednisolone in children [4][5]
  • Prednisone
    • 1-2mg/kg/day (60mg max) in one or two divided doses for 3-5 days
  • Methylprednisolone
    • 1mg/kg IV q 4–6hr
    • Only use IV if cannot tolerate PO since equal effectiveness between dosing routes[6]

Magnesium

  • Dose: 50mg/kg IV, max 2-4 g over 20 mins with close blood pressure monitoring
  • Smooth muscle relaxant
  • Duration of action approximately 20 min
  • In patients with moderate to severe asthma there is a decreased rate of admission with an NNT of 2[3]

Beta-agonist

  • Epinephrine
    • 1:1000 0.01mg/kg (max 0.3mg) IM, repeat as needed
  • Terbutaline
    • Given SQ, usual dose 0.01mg/kg up to 0.3mg.
    • Longer-acting beta2-agonist promoting bronchodilation

Assisted Ventilation

  • Non-invasive ventilation
    • Consider as alternative to intubation
    • Alleviates muscle fatigue which leads to larger tidal volumes
    • Maximize inspiratory support
      • Delta pressure 10
      • PEEP >4
    • May benefit from ketamine or dexmedetomidine to mildly sedate and allow the interface

Intubation

  • Push pull (bolus) fluids prior to intubation to maximize the patient's preload and ideally decrease the chance of the patient arresting
  • Consider induction with ketamine
    • Provides bronchodilation and sedation however it does promote secretions
    • Ketamine is the preferred induction agent for intubation in an asthmatic.
    • Dosing 1-2 mg/kg
  • Ventilation of asthmatic patients requires deep sedation
  • Ventilation settings
    • Assist-control ventilation
    • Resp rate
      • Start slow to avoid air-trapping and allow for longer expiration time
      • Consider I:E ratio of 1:2 or 1:3
    • Plateau pressure ideally <30
    • May require "permissive hypoventilation" and permissive hypercarbia and acidosis
      • Low peak pressure/avoidance of breath stacking more important than correcting CO2 [7]
    • Tidal volume 6-8cc/kg ideal wt
    • PEEP >4
    • Flow rate 80-100L/min
    • Keep FiO2 minimum to achieve SpO2 > 90%
  • Use bronchodilators even when intubated
  • Many patients require a continuous paralytic infusion for the first 24+ hrs of intubation

Outpatient Treatment

Severity Day Sx Night Sx Treatment (WHO 2008 Formulary)[8]
Mild intermittent, > 80% peak flow < 2/wk < 2/mo Albuterol MDI 100-200 mcg PRN QID
Mild persistent, > 80% peak flow >2/wk >2/mo Albuterol MDI 100-200 mcg PRN QID AND

Beclometasone 100-250 mcg BID

Moderate persistent, 60-80% peak flow Daily with exacerbations weekly > 1/wk Albuterol MDI 100-200 mcg PRN QID AND

Beclometasone 100-500 mcg BID AND

Salmeterol inhaled 50 mcg BID

Severe persistent, < 60% peak flow Continuous daily Frequent Albuterol MDI 100-200 mcg PRN QID AND

Beclometasone 1mg BID (high dose) AND

Salmeterol inhaled 50 mcg BID AND

theophylline, leukotriene antagonist, or PO prednisolone with taper

Disposition

  • Discharge
    • Often, patients will still have mild wheezing, but should have complete resolution of tachypnea, hypoxia, and improved work of breathing
    • A short course of glucocorticoids decreases chance of relapse [9])
    • Patient should generally continue albuterol at home q6hrs for at least the first 24hrs after discharge
    • A spacer should be prescribed to be used with the MDI to improve medication delivery to the lungs
  • Admit
    • If symptoms do not significantly improve or for severe exacerbations
  • Peak flow measurements maybe helpful when deciding disposition
    • Predicted = (30 x age (yrs)) + 30
    • PEF >70% predicted → high likelihood of successful discharge
    • PEF <40% predicted → should be admitted

See Also

External Links

References

  1. Camargo CA et al. Continuous versus intermittent beta- agonists for acute asthma. Cochrane Database Syst Rev. 2003;(4):CD001115. PMID: 14583926.
  2. National Asthma Education and Prevention Program (NAEPP), “Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma,” Clinical Practice Guidelines, National Institutes of Health, National Heart, Lung, and Blood Institute, NIH Publication No. 08-4051, prepublication 2007; available at http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.htm.
  3. 3.0 3.1 Rowe BH et al. Magnesium sulfate for treating exac- erbations of acute asthma in the emergency depart- ment. Cochrane Database Syst Rev. 2000;(2):CD001490. PMID: 10796650.
  4. Keeney, et al. Dexamethasone for Acute Asthma Exacerbations in Children: A Meta-analysis. Pediatrics. 2013-2273
  5. Cronin et al. "A Randomized Trial of Single-Dose Oral Dexamethasone Versus Multidose Prednisolone for Acute Exacerbations of Asthma in Children Who Attend the Emergency Department." Annals of EM. May 2016. 67(5):593-601
  6. Rowe BH, Keller JL, Oxman AD. Effectiveness of steroid therapy in acute exacerbations of asthma: a meta-analysis. Am J Emerg Med. Jul 1992;10(4):301-10
  7. Darioli, et al. Mechanical Controlled hypoventilation in status asthmaticus. Am Rev Respir Dis. 1984; 129 (3) 385-7
  8. Stuart MC et al. WHO Model Formulary 2008. http://www.who.int/selection_medicines/list/WMF2008.pdf.
  9. Chapman K. Effect of a short course of prednisone in the prevention of early relapse after the emergency room treatment of acute asthma. NEJM. 1991;324(12):788