MANAGEMENT OF COMMON ALLERGIC EMERGENCIES

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MANAGEMENT OF COMMON ALLERGIC EMERGENCIES

• M. SCOTT LINSCOTT, M.D.
• UNIVERSITY OF UTAH SCHOOL OF MEDICINE

2
CASE 1

• A 32 Y/O FEMALE PRESENTS WITH A HISTORY OF
  SEVERE WHEEZING FOR 24 HOURS. SHE HAS HAD ASTHMA
  SINCE SHE WAS 8 Y/O AND IS CURRENTLY USING
  FLUTICASONE AEROSOL (AZMACORT) 220 mcg bid,
  ALBUTEROL MDI 180 mcg q 4 HRS AND THEODUR 200 mg
  BID. VS BP 160/100, P 130, R 30, T 36.6 C. SHE
  IS IN ACUTE RESPIRATORY DISTRESS, GASPING FOR
  EACH BREATH, USING HER ACCESSORY MUSCLES AND
  SITTING IN THE SNIFFING POSITION. SHE IS UNABLE
  TO SPEAK MORE THAN 2-3 WORDS WITH EACH BREATH.
  BREATH SOUNDS ARE DECREASED AND SHE HAS WHEEZING
  WITH PROLONGED EXPIRATORY PHASE.

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WHAT ADDITIONAL HISTORY AND PHYSICAL FINDINGS
WOULD BE IMPORTANT?
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ADDITIONAL HISTORY, EXAM

• PREVIOUSLY STEROID DEPENDENT?
• PREVIOUS HOSPITALIZATIONS FOR ASTHMA?
• PREVIOUS ENDOTRACHEAL INTUBATIONS FOR ASTHMA?
• RECENT URI, OTHER INCITING FACTORS?
• PHYSICAL PULSUS PARADOXICUS?

5
HOW SHOULD THIS PATIENT BE
MANAGED?MONITORING / DIAGNOSIS?THERAPY?
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MONITORING / DIAGNOSIS

• ECG MONITOR, IV
• PULSE OXIMETER (INITIALLY ON ROOM AIR
  UNLESS THE PATIENT IS IN SEVERE DISTRESS)
• PEAK FLOW (PEF) / FEV1
• THEOPHYLLINE LEVEL
• ABG?
• CHEST X-RAY?

7
HOW SHOULD THIS PATIENT BE
MANAGED?MONITORING / DIAGNOSIS?THERAPY?
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THERAPY

• OXYGEN
• BETA AGONISTS
• INHALED BETA-2 AGONISTS - MDI, NEBULIZER, CPAP,
  BIPAP, ETC
• SYSTEMIC SQ/IV EPINEPHRINE OR TERBUTALINE
• IPRATROPIUM?
• CORTICOSTEROIDS - IV, ORAL, INHALED
• THEOPHYLLINE? MAGNESIUM? HELIOX? LEUKOTRIENE
  RECEPTOR ANTAGONISTS?

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SYSTEMIC BETA AGONISTS

• UNDERUTILIZED IN PATIENTS WITH SEVERE ACUTE
  ASTHMA
• INHALED BETA-2 AGONISTS ALONE MAY BE
  INEFFECTIVE
• TERBUTALINE OR EPI 0.3 - 0.5 mg SQ
• SAFE IN OLDER PTS (ESPECIALLY IF NO CAD)
• IV EPINEPHRINE (0.5-1.0 mcg/min) IF NO RESPONSE
  TO SQ OR INHALED BETA-2 AGONISTS
• AVOID ENDOTRACHEAL INTUBATION IF POSSIBLE
  (VERY HIGH PRESSURES, PNEUMOTHORAX)

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MDI VS NEBULIZER

• EFFICACY SIMILAR IF USE MDI WITH SPACER
  OR BREATH ACTIVATED MDI (MULTIPLE STUDIES)
• COST (DOLLARS MAN HOURS) MUCH LESS WITH
  MDI
• START WITH MDI (WITH SPACER) AND IF NOT
  EFFECTIVE, USE NEBULIZER
• IF NEBULIZER NOT EFFECTIVE, USE CPAP OR
  BIPAP (ANN EMERG MED 199526552 CHEST
  20031231018)

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DOSING OF INHALED BETA2 AGONISTS IN SEVERE
ASTHMA

• USE 4 SPRAYS (360 mcg) ALBUTEROL MDI WITH
  SPACER OR 6 mg ALBUTEROL (1.0 ml) WITH 2.0
  ml NS (NEBULIZER) NEBULIZED ATROPINE
  (ATROVENT) 500 mcg INITIALLY
• GIVE ALBUTEROL q 15 MINUTES OR BY CONTINUOUS
  NEBULIZATION
• MOST PATIENTS WITH ACUTE SEVERE ASTHMA DO
  POORLY BECAUSE THEY ARENT GIVEN ENOUGH
  BETA ADRENERGIC DRUGS!!!

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SYSTEMIC CORTICOSTEROIDS ORAL OR PARENTERAL?

• IF ACUTE, MILD OR MODERATE ORAL AS
  EFFECTIVE AS IV IN ALL STUDIES PLUS LESS
  EXPENSIVE
• IF ACUTE, SEVERE (VERY ILL) NO CONTROLLED
  STUDIES BUT PROBABLY BEST TO GIVE FIRST
  DOSE (S) IV
• DOSE PREDNISONE 40 - 60 mg po qd,
  SOLUMEDROL 1 - 2 mg/kg IV q 12-24 HOURS

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SYSTEMIC CORTICOSTEROIDS TO TAPER OR NOT TO
TAPER?

• WHY TAPER?
• IF USE FOR MORE THAN 14-21 DAYS, MAY SEE
  SUPPRESSION OF HYPOTHALAMIC - PITUITARY
  -ADRENAL AXIS AND IMMUNOSUPPRESSION
• IF USE FOR ACUTE EXACERBATIONS, MAY SEE
  EXACERBATION OF ASTHMA IF DON'T TAPER
  (LITTLE EVIDENCE TO SUPPORT THIS - IF
  OPTIMUM PEAK EXPIRATORY FLOW (PEF) HAS BEEN
  ACHIEVED)
• PROBABLY NO NEED TO TAPER IF OPTIMUM PEF
  IS ATTAINED BEFORE DISCONTINUING
  CORTICOSTEROIDS

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THEOPHYLLINE

• IN ACUTE ASTHMA PROBABLY SHOULD NOT BE
  USED AS PRIMARY THERAPY. MOST STUDIES SHOW
  MINIMAL OR NO ADDITIONAL BENEFIT AND
  INCREASED TOXICITY WHEN THEOPHYLLINE IS
  ADDED TO BETA AGONISTS AND CORTICOSTEROIDS.
  HOWEVER, SOME STUDIES DO SHOW BENEFIT IN PATIENTS
  REFRACTORY TO BETA-2 AGONIST THERAPY (CHEST
  20031231018)
• CHRONICALLY - MAY BE EFFECTIVE IN SOME
  CASES, ESP. NOCTURNAL ASTHMA AND COPD. NEW
  FDA RECOMMENDED MAXIMUM LEVEL - 15 mg/ml.
  BECAUSE OF ITS LOW THERAPEUTIC INDEX,
  PROBABLY SHOULD NOT BE FIRST-LINE DRUG FOR
  CHRONIC ASTHMA
• HOWEVER, IT IS INEXPENSIVE AND THEREFORE MAY BE
  THE ONLY OPTION IN SOME PATIENTS

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IPRATROPIUM, HELIOX, MAGNESIUM, LEUKOTRIENE
RECEPTOR ANTAGONISTS

• ALL MAY CAUSE MINIMAL ADDITIONAL
  BRONCHODILATION IN PTS WITH ACUTE ASTHMA
  TREATED WITH OPTIMUM BETA ADRENERGIC DRUGS
  AND STEROIDS, ESP. IN MODERATE-TO-SEVERE
  ASTHMA
• IN ACUTE ASTHMA, STUDIES EMPLOYING IPRATROPIUM
  INITIALLY WITH ALBUTEROL ARE CONFLICTING IN TERMS
  OF EFFICACY MOST RECENT STUDIES WOULD INDICATE
  EFFICACY.
• THEOPHYLLINE, HELIOX, MAGNESIUM AND LRA SHOULD
  PROBABLY BE RESERVED FOR THE SEVERE CASE
  WHICH IS REFRACTORY TO BETA AGONIST,
  IPRATROPIUM AND SYSTEMIC CORTICOSTEROID
  THERAPY

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CASE 2

• EMS CALLS TO INFORM YOU THAT THEY ARE
  TRANSPORTING A 22 YEAR OLD MALE WHO IS COMATOSE
  AND HAS A BP OF 60/40, PULSE OF 140, AND RESP OF
  16. HE WAS EATING AT A LOCAL THAI RESTAURANT
  WHEN HE TOLD HIS COMPANION THAT HIS THROAT FELT
  TIGHT AND THEN HE COLLAPSED. HE HAD INQUIRED OF
  THE WAITER WHETHER A CERTAIN ENTRÉE CONTAINED
  PEANUTS BECAUSE HE HAD A VIOLENT ALLERGY TO THEM.
  THE WAITER HAD ASSURED HIM THAT THERE WERE NO
  PEANUTS, PEANUT OILS, ETC. IN THIS DISH. HIS
  SYMPTOMS BEGAN WITHIN 5 MINUTES OF HIS EATING
  THIS ENTRÉE.

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MOST LIKELY DIAGNOSIS?WHAT WOULD YOU INSTRUCT
THE EMS PERSONNEL TO DO FOR THIS PATIENT?
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ANAPHYLACTIC SHOCKMANAGEMENT

• AT LEAST 2 LARGE BORE (16 GUAGE OR LARGER) IVs
• CRYSTALLOID (NS) WIDE OPEN (PRESSURE INFUSION IF
  POSSIBLE) TO DELIVER 1 LITER PER LINE IN FIRST
  5-10 MINUTES. PATIENT WILL OFTEN REQUIRE 10
  LITERS IN FIRST SEVERAL HOURS (MAJOR CAPILLARY
  LEAK)
• EPINEPHRINE 0.05-0.1 mg IV
• MONITOR BP AND PULSE
• CARDIAC MONITOR
• LIGHTS AND SIREN TO ED!!

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CASE 3

• A 35 YEAR OLD FEMALE PRESENTS WITH THE ACUTE
  ONSET OF A VERY PRURITIC RASH SIX HOURS PRIOR TO
  ADMISSION. SHE HAD A SIMILAR RASH TWO YEARS AGO
  WHICH CLEARED UP IMMEDIATELY WITH 50 mg OF
  DIPHENHYDRAMINE ORALLY. SHE TOOK DIPHENHYDRAMINE
  AGAIN THIS TIME WITH SLIGHT IMPROVEMENT IN THE
  ITCHING FOR TWO HOURS. THE ITCHING AGAIN BECAME
  SEVERE AND THE RASH SPREAD. SHE DENIES TAKING
  MEDICATIONS OR ANY NEW SOAPS, MAKEUP, ETC. THERE
  IS A GENERALIZED ERUPTION OF RAISED WHEALS WITH
  ERYTHEMATOUS MARGINS WHICH THE PATIENT IS
  VIGOROUSLY SCRATCHING.

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ADDITIONAL HISTORY?(POTENTIALLY LIFE
THREATENING PROBLEM?)
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ADDITIONAL HISTORY?

• MUST WORRY ABOUT ANGIOEDEMA (SAME PROCESS AS
  URTICARIA, BUT INVOLVING DEEPER TISSUES)
• MOST SENSITIVE QUESTION RE LARYNGEAL ANGIOEDEMA
  ANY CHANGE IN YOUR VOICE (HOARSENESS)?
• THROAT TIGHTNESS?
• STRIDOR?
• LIP OR TONGUE SWELLING?

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DIAGNOSIS?MANAGEMENT?
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ACUTE URTICARIAMANAGEMENT

• DIPHENHYDRAMINE 25 mg IV
• H2 BLOCKERS IV
• RANITIDINE 50 MG IV
• FAMOTIDINE 20 mg IV
• CIMETIDINE 300 MG IV
• IF PATIENT HAS WHEEZING, HOARSENESS, THROAT
  TIGHTNESS, LIP/TONGUE SWELLING EPI 0.3 0.5 mg
  sq
• REFRACTORY HYDROXYZINE 50 mg po, DOXEPIN 50 mg
  po, SYSTEMIC STEROIDS, REFER TO DERMATOLOGIST FOR
  BIOPSY TO R/O URTICARIAL VASCULITIS

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H1 BLOCKERS

• OLDER (FIRST GENERATION) DIPHENHYDRAMINE
  (BENADRYL), CHLORPHENIRAMINE (CHLORTRIMETON),
  CYPROHEPTADINE (PERIACTIN), HYDROXYZINE (ATARAX,
  VISTARIL), PROMETHAZINE (PHENERGAN), CLEMASTINE
  (TAVIST), ETC.
• NEWER (SECOND GENERATION) LORATADINE
  (CLARITIN), CETIRIZINE (ZYRTEC), FEXOFENADINE
  (ALLEGRA), ASTEMIZOLE (HISMANAL), TERFENADINE
  (SELDANE),

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H1 BLOCKING ANTIHISTAMINES
DRUG
COST/DAY
AS
PAR
MET
UR
VA
ON
DIPHENHYDR
-


-
HEP
lt30
0.85
HYDROXYZINE
o


-
REN
lt30
0.90
TERFENADINE




HEP
gt60
ASTEMIZOLE




HEP
gt120
-
LORATADINE



HEP
gt60
2.50
CETIRIZINE


-

REN
lt60
2.10
-
2.40
HEP
gt60
FEXOFENADINE



DAILY COST TO PATIENT OF 30 DAY
PRESCRIPTION (AVERAGE OF SMITHS, DANS,
WALMART, UUMC) IN SLC, UTAH, USA SEPT 2003
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SUMMARY

• ASTHMA
• IF MILD, ALBUTEROL IPRATROPRIUM
• IF MODERATE, ABOVE PLUS SYSTEMIC CORTICOSTEROIDS
• IF SEVERE, ABOVE PLUS SYSTEMIC BETA AGONISTS
  GET CXR AND ABGs
• EPINEPHRINE DRIP AVOID ET INTUBATION
• ANAPHYLACTIC SHOCK
• MOST IMPORTANT IS MASSIVE IV CRYSTALLOID INFUSION
• EPINEPHRINE 0.05-0.1 mg IV
• ANTIHISTAMINES, STEROIDS?
• ACUTE URTICARIA/ANGIOEDEMA
• DIPHENHYDRAMINE 25 mg IV
• H2 BLOCKER IV
• EPI IF SUSPECT ANGIOEDEMA, ESP. OF THE
  LARYNX