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Sting, Bee, Emergency Medicine

Basics

Description

- Large local reaction: - Similar to local reaction but affects larger area or entire limbs - Peaks at 48 hr and can last several days - Mild to moderate fever

- GI: - Nausea - Vomiting - Diarrhea - Abdominal pain

- Cardiovascular: - Hypotension - Chest pain - Tachycardia - Shock

- Other: - Urticaria - Pruritus - Flushing

- CBC, electrolytes, BUN, creatinine, glucose, arterial blood gases (ABGs): - Not routine - Consider when significant systemic effects present

- Systemic reactions: - Epinephrine for respiratory symptoms/hypotension - Antihistamines " H1 (diphenhydramine) and H2 (cimetidine, ranitidine, or famotidine) blockers - Steroids (prednisone, methylprednisolone, or dexamethasone) - Inhaled ²-agonist for wheezing/shortness of breath - For persistent hypotension: - 0.9% NS IV fluid resuscitation - Vasopressor (epinephrine/α-adrenergic) for hypotension resistant to IV fluids

- Removal of remnants of stinger at site of envenomation (bees may leave stingers with venom sacs) by scraping, not squeezing - Local reactions: - Cool compress - Elevation - Remove constrictive clothing or jewelry - Topical antihistamine/topical steroidal cream as needed - Oral antihistamine or steroids as needed

  • Injection of hymenoptera venom causes:Release of biologic aminesLocal or systemic allergic reactions
  • Reactions are:Usually IgE-mediated type I hypersensitivity reactionsRarely type III (Arthus) hypersensitivity reactions

Etiology

  • Hymenoptera " order of the phylum Arthropoda
  • Includes bees (Apidae family), wasps and hornets (Vespidae family), fire ants (Formicidae family)

Diagnosis

Signs and Symptoms

History

History and physical exam " keys to diagnosis

Physical Exam

5 types of reactions to stings:

  • Local reaction:Most common type of reactionLocal pain, erythema, and edema at sting siteSymptoms occur immediately and resolve within 1 " 2 hr
  • Large local reaction:Similar to local reaction but affects larger area or entire limbsPeaks at 48 hr and can last several daysMild to moderate fever
  • Systemic reaction:Includes anaphylaxisCan be fatal (usually owing to respiratory failure)Respiratory:WheezingCoughingStridorShortness of breathHoarsenessAngioedemaGI:NauseaVomitingDiarrheaAbdominal painCardiovascular:HypotensionChest painTachycardiaShockOther:UrticariaPruritusFlushingSymptoms occur within 15 " 20 min and last ≤72 hr
  • Toxic reaction:Result of multiple stings and large doses of venomSymptoms similar to anaphylaxis
  • Unusual reactions:Owing to unusual immune responseVasculitisNephrosisSerum sicknessNeuritisEncephalitisReaction delayed (days to weeks after sting)

Essential Workup

  • History and physical exam key to diagnosis
  • No radiologic or lab test will confirm hymenoptera envenomation or anaphylaxis

Diagnosis Tests & Interpretation

Lab

  • CBC, electrolytes, BUN, creatinine, glucose, arterial blood gases (ABGs):Not routineConsider when significant systemic effects present

Diagnostic Procedures/Surgery

ECG:

  • When significant systemic effects present in patients at risk for cardiovascular disease

Differential Diagnosis

  • Insect bites sometimes cause pain; stings always cause pain.
  • Cellulitis:Difficult to distinguish between large local reactions and cellulitisInfections of hymenoptera envenomations are rare and usually caused by wasp envenomations.Local reaction can resemble periorbital cellulitis.
  • Gout
  • Soft tissue trauma
  • Systemic/toxic reactions:Pulmonary embolusAnaphylaxis from different agentHyperventilatory syndrome/anxietyAcute coronary syndrome

Treatment

Pre-Hospital

Most deaths occur within 1st hour owing to either respiratory obstruction or anaphylaxis causing cardiovascular and respiratory collapse.

Initial Stabilization/Therapy

Acute Severe Systemic Reaction/Anaphylaxis

  • ABCs:Intubation/ventilation with rapidly increasing signs of laryngeal compromiseOxygen0.9% normal saline (NS) IV access
  • Epinephrine SC/IV
  • Antihistamines IV
  • Corticosteroids
  • When signs of systemic reactions:Assess for patent airwayEstablish IV access

Ed Treatment/Procedures

  • Systemic reactions:Epinephrine for respiratory symptoms/hypotensionAntihistamines " H1 (diphenhydramine) and H2 (cimetidine, ranitidine, or famotidine) blockersSteroids (prednisone, methylprednisolone, or dexamethasone)Inhaled ²-agonist for wheezing/shortness of breathFor persistent hypotension:0.9% NS IV fluid resuscitationVasopressor (epinephrine/α-adrenergic) for hypotension resistant to IV fluids
  • Removal of remnants of stinger at site of envenomation (bees may leave stingers with venom sacs) by scraping, not squeezing
  • Local reactions:Cool compressElevationRemove constrictive clothing or jewelryTopical antihistamine/topical steroidal cream as neededOral antihistamine or steroids as needed

Medication

  • Albuterol, ²-agonist (inhaled): 3 mg in 5 mL NS (peds: 0.1 mg/kg of 5 mg/mL concentration) via nebulization
  • Cimetidine: 300 mg (peds: 5 mg/kg) IV/IM/PO
  • Diphenhydramine:50 " 100 mg (peds: 1 mg/kg) IV for severe reactions25 " 50 mg (peds: 1 mg/kg) PO QID for severe local reactions
  • Epinephrine:0.1 mg: 1 mL of 1:10,000 dilution (peds: 0.01 mg/kg 0.1 mL/kg of 1:10,000 dilution up to 1 mL) IV over 5 min for shock0.3 mg (0.3 mL of 1:1,000 dilution); (peds: 0.01 mg/kg up to 0.5 mg) SC for severe reactions but not in shock
  • Famotidine: 40 mg IV (peds: 1 mg/kg/d div. BID IV)
  • Methylprednisolone: 125 mg (peds: 1 " 2 mg/kg) IV
  • Norepinephrine: 2 " 4 Όg/kg/min (peds: 0.1 Όg/kg/min) titrated continuous infusion
  • Prednisone: 60 mg (peds: 1 " 2 mg/kg) PO
  • Ranitidine: 50 mg IV/IM (peds: 2 " 4 mg/kg/d div. q6 " 8h IV/IM)

Follow-Up

Disposition

Admission Criteria

  • Worsening symptoms, airway compromise
  • Persistent unstable vital signs require ICU admission.
  • Life-threatening reaction requires 24-hr observation.
  • Systemic reaction requires minimum of 6 hr of observation.

Discharge Criteria

  • Minimal isolated local reaction
  • Systemic reactions that resolve and do not recur during 6-hr observation period

Issues for Referral

Follow-up:

  • Provide patients with life-threatening reactions, emergency anaphylaxis kits (EpiPen; peds: EpiPen Jr if <15 kg), and medical identification bracelets (Medi-Alert).
  • Systemic reaction requires follow-up for possible immunotherapy.

Followup Recommendations

Allergist follow-up for patients with systemic reactions.

Pearls and Pitfalls

  • Treat patients who present with systemic reactions to bee stings aggressively.
  • Provide prescriptions for EpiPen to patients discharged after presenting with life-threatening reactions to bee stings.

Additional Reading

  • Bahna SL. Insect sting allergy: A matter of life and death. Pediatr Ann. 2000;29:753 " 758.
  • Freeman T. Stings of hymenoptera insects: Reaction types and acute management. UpToDate. Accessed on Sept 25, 2009.
  • McDougle L, Klein GL, Hoehler FK. Management of hymenoptera sting anaphylaxis: A preventive medicine survey. J Emerg Med. 1995;13:9 " 13.
  • Moffitt JE, Golden DB, Reisman RE. Stinging insect hypersensitivity: A practice parameter update. J Allergy Clin Immunol. 2004;114:869 " 886.
  • Reisman RE. Insect stings. N Engl J Med. 1994;331:523 " 527.

See Also (Topic, Algorithm, Electronic Media Element)

Anaphylaxis

Codes

ICD9

989.5 Toxic effect of venom

ICD10

T63.441A Toxic effect of venom of bees, accidental, init

SNOMED

  • 241820008 Bee sting (disorder)
  • 282095007 Allergic reaction to bee sting (disorder)
  • 241931004 Bee sting-induced anaphylaxis (disorder)