Anaphylaxis: Difference between revisions

No edit summary
No edit summary
Line 1: Line 1:
=Definition=
==Background==
===Definition===
Anaphylaxis is highly likely when ANY ONE of the following criteria is fulfilled
Anaphylaxis is highly likely when ANY ONE of the following criteria is fulfilled


==Criterion 1 (90% of patients)==
'''Criterion 1 (90% of patients)'''
#Acute onset of an illness involving the skin, mucosal tissue, or both AND at least one of the following:
#Acute onset of an illness involving the skin, mucosal tissue, or both AND at least one of the following:
##Respiratory Compromise
##Respiratory Compromise
##Reduced blood pressure or associated symptoms ([[Syncope]], [[Dizziness]])
##Reduced blood pressure or associated symptoms ([[Syncope]], [[Dizziness]])


==Criterion 2 (10-20% of pts)==
'''Criterion 2 (10-20% of pts)'''
#TWO OR MORE of the following that that occur rapidly after exposure to a LIKELY allergen for that patient
#TWO OR MORE of the following that that occur rapidly after exposure to a LIKELY allergen for that patient
##Involvement of the skin-mucosal tissue (hives, swollen lips-tongue-uvula)
##Involvement of the skin-mucosal tissue (hives, swollen lips-tongue-uvula)
Line 14: Line 15:
##Persistent gastrointestinal symptoms: ([[Vomiting|vomiting]], [[Diarrhea|diarrhea]], crampy [[Abd Pain|abdominal pain]])
##Persistent gastrointestinal symptoms: ([[Vomiting|vomiting]], [[Diarrhea|diarrhea]], crampy [[Abd Pain|abdominal pain]])


==Criterion 3==
'''Criterion 3'''
#[[Reduced BP|Hypotension]] after exposure to a KNOWN allergy for that patient (minutes to hours):
#[[Reduced BP|Hypotension]] after exposure to a KNOWN allergy for that patient (minutes to hours):
##Adults: systolic blood pressure (SBP) <90 mmHg or >30% reduction from baseline
##Adults: systolic blood pressure (SBP) <90 mmHg or >30% reduction from baseline
Line 22: Line 23:
###11 years - 17 years: SBP <90 mmHg
###11 years - 17 years: SBP <90 mmHg


=Differential Diagnosis=
==Clinical Features==
*Cutaneous symptoms: 90%
*Respiratory symptoms: 70%
*Gastrointestinal symptoms: 40%
*Cardiovascular symptoms: 35%
 
==Differential Diagnosis==
#Generalized urticaria
#Generalized urticaria
#[[Angioedema]]
#[[Angioedema]]
Line 28: Line 35:
#Anxiety attack
#Anxiety attack
#[[MI|Acute Coronary Syndromes]]
#[[MI|Acute Coronary Syndromes]]
#Scombroidosis  
#[[Scombroidosis]]
#Other forms of shock
#Other forms of shock


=Presentation=
==Management==
*Cutaneous symptoms: 90%
#'''[[Epinephrine]]'''
*Respiratory symptoms: 70%
##1:1000 '''IM''' 0.3 - 0.5mg (0.3 - 0.5mL) every 5 - 15 minutes<ref>Dhami S. et al. Management of anaphylaxis: a systematic review. Allergy. 69 (2014) 168–175. http://onlinelibrary.wiley.com/store/10.1111/all.12318/asset/all12318.pdf?v=1&t=hrspdbpk&s=8067bfd5903c7ffebf4a274f062a71633ebe0507</ref>
*Gastrointestinal symptoms: 40%
###Give as soon as possible
*Cardiovascular symptoms: 35%
###Always IM initially  
 
###If response to IM is inadequate: give epinephrine infusion 1:10,000 2 - 10 µg/min
=Treatment=
###'''How to make a quick epi drip:''' ''Take your code-cart epi (it doesn't matter if it's 1:1,000 or 1:10,000) and inject 1mg into a liter bag of NS.  Final concentration is 1mcg/ml.  Run at 1cc/hr and titrate to effect''.
==[[Epinephrine]]==
##Pediatric: [[Epinephrine]] '''1:1000 0.01 mg/kg (max 0.5mg) IM''' every 5 to 15 minutes
#1:1000 '''IM''' 0.3 - 0.5mg (0.3 - 0.5mL) every 5 - 15 minutes<ref>Dhami S. et al. Management of anaphylaxis: a systematic review. Allergy. 69 (2014) 168–175. http://onlinelibrary.wiley.com/store/10.1111/all.12318/asset/all12318.pdf?v=1&t=hrspdbpk&s=8067bfd5903c7ffebf4a274f062a71633ebe0507</ref>
###IV infusion: 0.05 - 1 mcg/kg/min
##Give as soon as possible
#'''Supplemental oxygen'''
##Always IM initially  
##''Consider [[Intubation|endotracheal intubation]] if airway edema present''
##If response to IM is inadequate: give epinephrine infusion 1:10,000 2 - 10 µg/min
#'''Normal saline bolus'''
##'''How to make a quick epi drip:''' ''Take your code-cart epi (it doesn't matter if it's 1:1,000 or 1:10,000) and inject 1mg into a liter bag of NS.  Final concentration is 1mcg/ml.  Run at 1cc/hr and titrate to effect''.
##If unresponsive to [[epinephrine]] assume distributive [[Shock|shock]] and give 1 - 2 liters of normal saline
#Pediatric: [[Epinephrine]] '''1:1000 0.01 mg/kg (max 0.5mg) IM''' every 5 to 15 minutes
#'''Glucagon'''
##IV infusion: 0.05 - 1 mcg/kg/min
##1 - 2mg IV over 5 minutes followed by infusion of 5 - 15 µg/min
##If taking beta-blocker AND unresponsive to [[Epi|epinephrine]]
#'''Also consider'''
##Albuterol
###for bronchospasm resistant to IM epinephrine
##Antihistamines (for symptom control AFTER hemodynamically stable)
###Diphenhydramine: 25 to 50 mg IV
###Ranitidine: 50 mg IV (minimal evidence to support this)
##Glucocorticoid
###MAY blunt biphasic reaction although little evidence to support usage<ref>Choo KJ, Simons E, Sheikh A: Glucocorticoids for the treatment of anaphylaxis: Cochrane systematic review. Allergy 2010; 65:1205-1211.</ref>
###Methylprednisolone: *125 mg IV (2mg/kg in children)
###Dexamethasone: 10mg IV or PO (0.6mg/kg in children)


==Supplemental oxygen==
===Expected Course===
''Consider [[Intubation|endotracheal intubation]] if airway edema present''
*Uniphasic (80-90%)
==Normal saline bolus==
**Symptoms peak within 30 minutes to 1 hour after onset, resolve within 30 minutes to 1 hour of receiving treatment
*If unresponsive to [[epinephrine]] assume distributive [[Shock|shock]] and give 1 - 2 liters of normal saline
*Biphasic (10-20%)
**Uniphasic response, followed by asymptomatic period of hour or more, then return of symptoms
**The second phase does not necessarily resemble the first!
**More likely with a severe initial presentation, hypotension, and recurrent epinephrine dosing requirements in the emergency department<ref>Ellis AK, Day JH: Incidence and characteristics of biphasic anaphylaxis: A prospective evaluation of 103 patients. Ann Allergy Asthma Immunology. 2007; 98:64-69</ref>
**Little evidence to support the use of discharge steroids to prevent a biphasic reaction
**0.4% of patients with anaphylaxis had a rebound event while in the ED<ref name="biphasic"/>


==Glucagon==
==Disposition==
*1 - 2mg IV over 5 minutes followed by infusion of 5 - 15 µg/min
*If taking beta-blocker AND unresponsive to [[Epi|epinephrine]]
 
==Also consider==
===Albuterol===
*for bronchospasm resistant to IM epinephrine
===Antihistamines===
*only for sympton control (hives, itching) AFTER hemodynamically stable
===Diphenhydramine===
*25 to 50 mg IV
===Ranitidine===
*50 mg IV (minimal evidence to support this)
===Glucocorticoid===
*MAY blunt biphasic reaction although little evidence to support usage<ref>Choo KJ, Simons E, Sheikh A: Glucocorticoids for the treatment of anaphylaxis: Cochrane systematic review. Allergy 2010; 65:1205-1211.</ref>
*Methylprednisolone: *125 mg IV (2mg/kg in children)
*Dexamethasone: 10mg IV or PO (0.6mg/kg in children)
 
=Course=
==Uniphasic (80-90%)==
*Symptoms peak within 30 minutes to 1 hour after onset, resolve within 30 minutes to 1 hour of receiving treatment
==Biphasic (10-20%)==
*Uniphasic response, followed by asymptomatic period of hour or more, then return of symptoms
*The second phase does not necessarily resemble the first!
*More likely with a severe initial presentation, hypotension, and recurrent epinephrine dosing requirements in the emergency department<ref>Ellis AK, Day JH: Incidence and characteristics of biphasic anaphylaxis: A prospective evaluation of 103 patients. Ann Allergy Asthma Immunology. 2007; 98:64-69</ref>
*Little evidence to support the use of discharge steroids to prevent a biphasic reaction
*0.4% of patients with anaphylaxis had a rebound event while in the ED<ref name="biphasic"/>
 
=Disposition=
*Admit: Severe and moderate presentations especially if symptoms did not respond promptly to epinephrine or required repeat dosing
*Admit: Severe and moderate presentations especially if symptoms did not respond promptly to epinephrine or required repeat dosing
*Discharge: Symptom-free for at least 4 hours and mild initial presentation  
*Discharge: Symptom-free for at least 4 hours and mild initial presentation  
**Send home with an epinephrine autoinjector! (Epi-Pen)
**Send home with an epinephrine autoinjector! (Epi-Pen)
**Up to 6% of the people with anaphylaxis have a repeat ED visit for anaphylaxis within 7 days<ref name="biphasic">unau BE et al. Incidence of Clinically Important Biphasic Reactions in Emergency Department Patients With Allergic Reactions or Anaphylaxis. Ann Emerg Med. 2013 Nov 13</ref>
**Up to 6% of the people with anaphylaxis have a repeat ED visit for anaphylaxis within 7 days<ref name="biphasic">unau BE et al. Incidence of Clinically Important Biphasic Reactions in Emergency Department Patients With Allergic Reactions or Anaphylaxis. Ann Emerg Med. 2013 Nov 13</ref>


=See Also=
=See Also=

Revision as of 01:25, 3 April 2014

Background

Definition

Anaphylaxis is highly likely when ANY ONE of the following criteria is fulfilled

Criterion 1 (90% of patients)

  1. Acute onset of an illness involving the skin, mucosal tissue, or both AND at least one of the following:
    1. Respiratory Compromise
    2. Reduced blood pressure or associated symptoms (Syncope, Dizziness)

Criterion 2 (10-20% of pts)

  1. TWO OR MORE of the following that that occur rapidly after exposure to a LIKELY allergen for that patient
    1. Involvement of the skin-mucosal tissue (hives, swollen lips-tongue-uvula)
    2. Respiratory compromise
    3. Hypotension or associated symptoms
    4. Persistent gastrointestinal symptoms: (vomiting, diarrhea, crampy abdominal pain)

Criterion 3

  1. Hypotension after exposure to a KNOWN allergy for that patient (minutes to hours):
    1. Adults: systolic blood pressure (SBP) <90 mmHg or >30% reduction from baseline
    2. Pediatrics
      1. 1 month - 1 year: SBP <70 mmHg
      2. 1 year - 10 years: SBP <(70 mmHg + [2 x age])
      3. 11 years - 17 years: SBP <90 mmHg

Clinical Features

  • Cutaneous symptoms: 90%
  • Respiratory symptoms: 70%
  • Gastrointestinal symptoms: 40%
  • Cardiovascular symptoms: 35%

Differential Diagnosis

  1. Generalized urticaria
  2. Angioedema
  3. Asthma exacerbation
  4. Anxiety attack
  5. Acute Coronary Syndromes
  6. Scombroidosis
  7. Other forms of shock

Management

  1. Epinephrine
    1. 1:1000 IM 0.3 - 0.5mg (0.3 - 0.5mL) every 5 - 15 minutes[1]
      1. Give as soon as possible
      2. Always IM initially
      3. If response to IM is inadequate: give epinephrine infusion 1:10,000 2 - 10 µg/min
      4. How to make a quick epi drip: Take your code-cart epi (it doesn't matter if it's 1:1,000 or 1:10,000) and inject 1mg into a liter bag of NS. Final concentration is 1mcg/ml. Run at 1cc/hr and titrate to effect.
    2. Pediatric: Epinephrine 1:1000 0.01 mg/kg (max 0.5mg) IM every 5 to 15 minutes
      1. IV infusion: 0.05 - 1 mcg/kg/min
  2. Supplemental oxygen
    1. Consider endotracheal intubation if airway edema present
  3. Normal saline bolus
    1. If unresponsive to epinephrine assume distributive shock and give 1 - 2 liters of normal saline
  4. Glucagon
    1. 1 - 2mg IV over 5 minutes followed by infusion of 5 - 15 µg/min
    2. If taking beta-blocker AND unresponsive to epinephrine
  5. Also consider
    1. Albuterol
      1. for bronchospasm resistant to IM epinephrine
    2. Antihistamines (for symptom control AFTER hemodynamically stable)
      1. Diphenhydramine: 25 to 50 mg IV
      2. Ranitidine: 50 mg IV (minimal evidence to support this)
    3. Glucocorticoid
      1. MAY blunt biphasic reaction although little evidence to support usage[2]
      2. Methylprednisolone: *125 mg IV (2mg/kg in children)
      3. Dexamethasone: 10mg IV or PO (0.6mg/kg in children)

Expected Course

  • Uniphasic (80-90%)
    • Symptoms peak within 30 minutes to 1 hour after onset, resolve within 30 minutes to 1 hour of receiving treatment
  • Biphasic (10-20%)
    • Uniphasic response, followed by asymptomatic period of hour or more, then return of symptoms
    • The second phase does not necessarily resemble the first!
    • More likely with a severe initial presentation, hypotension, and recurrent epinephrine dosing requirements in the emergency department[3]
    • Little evidence to support the use of discharge steroids to prevent a biphasic reaction
    • 0.4% of patients with anaphylaxis had a rebound event while in the ED[4]

Disposition

  • Admit: Severe and moderate presentations especially if symptoms did not respond promptly to epinephrine or required repeat dosing
  • Discharge: Symptom-free for at least 4 hours and mild initial presentation
    • Send home with an epinephrine autoinjector! (Epi-Pen)
    • Up to 6% of the people with anaphylaxis have a repeat ED visit for anaphylaxis within 7 days[4]

See Also

Sources

  1. Dhami S. et al. Management of anaphylaxis: a systematic review. Allergy. 69 (2014) 168–175. http://onlinelibrary.wiley.com/store/10.1111/all.12318/asset/all12318.pdf?v=1&t=hrspdbpk&s=8067bfd5903c7ffebf4a274f062a71633ebe0507
  2. Choo KJ, Simons E, Sheikh A: Glucocorticoids for the treatment of anaphylaxis: Cochrane systematic review. Allergy 2010; 65:1205-1211.
  3. Ellis AK, Day JH: Incidence and characteristics of biphasic anaphylaxis: A prospective evaluation of 103 patients. Ann Allergy Asthma Immunology. 2007; 98:64-69
  4. 4.0 4.1 unau BE et al. Incidence of Clinically Important Biphasic Reactions in Emergency Department Patients With Allergic Reactions or Anaphylaxis. Ann Emerg Med. 2013 Nov 13
  • Brown SGA, Mullins RJ and Gold MS. Anaphylaxis: diagnosis and management, MJA 2006; 185: 283–289
  • Ewan PW. ABC of allergies – Anaphylaxis, BMJ 1998; 316: 1442-1445
  • Simons FER, Gu X, Simons KJ. Epinephrine absorption in adults: Intramuscular versus subcutaneous injection, J Allergy Clin Immunol 2001;108:871-3
  • Lieberman P et al. The diagnosis and management of anaphyalxis: An updated practice parameter, J Allergy Clin Immunol 2005;115;3:S483-S523
  • Sheikh A, Shehata YA, Brown SGA, Simons FER. Adrenaline (epinephrine) for the treatment of anaphylaxis with and without shock. Cochrane Database of Systematic Reviews 2008, Issue 4. Art. No.: CD006312. DOI:10.1002/14651858.CD006312.pub2
  • Second symposium on the definition and management of anaphylaxis: summary report--Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium.