1. S
Anaphylaxis
Case Examination – Diagnosis, and management
of anaphylaxis in the pre-hospital setting
Adam Khan
MCoP Paramedic Clinical Tutor
2. Aim:
The student should be able to demonstrate a clear
understanding of the safe approach, diagnosis and timely
management of a patient presenting with anaphylaxis in the
pre-hospital setting.
3. Objectives:
S Understand the causes, prevalence & clinical
manifestation of anaphylaxis.
S Demonstrate a safe approach to a patient presenting with
anaphylaxis.
S Understand the diagnosis and management of a patient
presenting with acute life-threatening anaphylaxis.
S Understand the definitive management and referral
options to a patient suffering with anaphylaxis
4. Case Presentation:
you are dispatched to a 30-year-old female ‘Louise’ who is
complaining of acute onset of dyspnea.
S Acute onset of dyspnea, choking.
S Occurrence following what is described as a ‘Bee sting’
S Previous medical history: Childhood Asthma
6. Case Presentation: continued
Patient Assessment Triangle (PAT):
S Marginally obstructed airway.
S resp. rate 32 resp/min. Shallow & laboured.
S Flushed in appearance, clear agitation, swelling around the
eyes and mouth.
S Palpable Radial pulses, bi-laterally rate of 133 b/min.
S Responding verbally in broken sentences – clear hoarse voice
7. Anaphylaxis: What is it?
S Anaphylaxis is a severe, life-threatening, generalised
or systemic hypersensitivity reaction
S Multisystem involvement, including the airway, vascular
system, gastro intestinal (GI) tract and skin and central
nervous system.
S Acute onset.
8. Anaphylaxis: What is it?
Patients who have anaphylactic reaction have life-
threatening airway and/or breathing and/or circulation
problems usually associated with skin and mucosal
changes
Resuscitation council UK (2012)
9. Causes: of anaphylaxis
Stings 47
Nuts 32
Food 13
Food Possible Cause 17
Antibiotics 27
Anaesthetic Drugs 39
Other Drugs 24
Contrast Media 11
Other 3 Figures taken from Resuscitaiton Council (UK) 2008.
Table 1. Suspected triggers for fatal
anaphylactic reactions in the UK between
1992-2001
10. Lifetime Prevalence:
S According to the Resuscitation Council (2008) approx. in
1 in 1,333 of the English population have experienced
anaphylaxis at some point in their lives.
S The current incidence rate suggests that between 30 and
950 cases per 100,000 persons per year present in the
ED with anaphylaxis
11. Anaphylaxis: Mortality
S Post Mortem Findings:
S Airway (laryngeal) and tissue (visceral) edema
S Gastrointestinal Hemorrhage
S Myocardial injury
12. Anaphylaxis: Risk Factors
S Fatal cases – 4%
S Risk factors
S Asthmatics
S Mast Cell Disease – (rare)
S Personal/Familial history of anaphylaxis
S Age
S Sex
13. Anaphylaxis – Clinical Presentation
S The Skin (Integumentary
System)
S Pruritus (Itching), Urticaria
(Hives), Angioedema,
Flushing
Example of urticaria (hives) presenting in a child
14. Anaphylaxis – Clinical Presentation
S Angioedema affecting
the eyes and mouth.
S If left untreated this can
develop into a life-
threatening airway
obstruction
15. Anaphylaxis – Clinical Presentation
S Respiratory System:
S Dyspnea, Tachypnoea, Universal Wheeze/crackles, Stridor and/or hoarseness,
throat swelling
S Cardiovascular system:
S Hypotension, Hypoxia, Tachycardia, arrhythmias
S Gastro-Intestinal system:
S Nausea, Diarrhea, Stomach cramp, Bloating and/or abdominal distension,
vomiting
S Central Nervous System (CNS)
S Confusion, Dizziness, Headache, agitation and/or anxiety
16. Case Presentation:
S Vital Signs:
S Angioedema, Dyspnoea & tachypnoea 32 r/min
S SpO2: 89% (air)
S Tachycardia: 133 b/min
S Blood pressure: 88/52 mm/hg
S Temperature: 37.1 degrees Celsius
S 12 lead ECG: Sinus Tachycardia
S Blood sugar: 6.6
17. Anaphylaxis: Initial management
S Should consist of:
S Removal of offending agent (if possible)
S Rapid primary assessment ABCDE
S Focused Secondary assessment which includes
S Head to toe physical assessment
S NIBP
S 12 Lead ECG monitoring
18. Anaphylaxis:
Initial
management
Algorithm to the right indicates
the steps required to
appropriately manage a patient
suffering with acute onset of
sever anaphylaxis
Algorithm taken from Resus Council UK 2012
19. Anaphylaxis: Treatment
S Joint Royal Colleges Ambulance Liaison Committee (JRCALC)
S ABC Assessment – Anaphylaxis
S OXYGEN – 15L if SpO2 <95%
S ADRENALINE (ADX) 1:1,000 Intra-muscular (IM) 500 mcgs
S HYDROCORTISONE (HYC) Intra-venous/muscular 200mgs
S SALBUTAMOL (SLB) Nebulised 5.0mg
20. Anaphylaxis: Treatment (cont.)
S CHLORPHENAMINE (CPH) Intra-venous 10mg
S SODIUM CHLORIDE (SCP) Intra-venous. 250 mL (titrated)
S NOTE:
S Establishing IV access should not delay transport to ED
S Adrenaline can be re-administered after 5 minutes if no effect
S Hydrocortisone is considered if transport time to ED is >30 mins
21. Transport Considerations
S Rapid Transport to Accident & Emergency
S ATMIST pre-alert en-route
S Consider HEMS if in a rural location or >45mins from hospital
22. Anaphylaxis: Temporal Pattern
S Uni-phasic:
S Singular allergic reaction, can be self limiting
S Bi-phasic:
S Initial allergic reaction
S Recurrence of same manifestations up to 8hrs later
S Protracted
S Up to 32 hours
S May not be prevented by glucocorticoids
23. Further treatment:
S ED will consider admittance if patient:
S Presents with biphasic or protracted reactions.
S If this is the patients first reaction.
S Age of patient – Risk management
S Children
S Elderly
S Referral onto an immunologist or allergy specialist will be
required
24. Differential Diagnosis
S Life Threatening:
S Severe Asthma
S Sepsis (SIRS)
S Pulmonary Embolism (PE)
S Choking
S Non life-threatening
S Syncope (vasovagal
episode)
S Panic Attack
S Idiopathic Urticaria
S Isolated Angioedema
25. Summary:
S Anaphylaxis is a life-threatening condition.
S Prompt identification, assessment and management is
vital for positive outcomes.
S Rapid transport is key to definitive treatment. Do not
delay on scene time
S Be aware of future treatment options
Editor's Notes
Understand the clinical differences between an allergy and anaphylaxis
What are your main considerations when approaching a patient, not just suffering with anaphylaxis?
What are the key clinical features of anaphylaxis?
Once diagnosed, what will be your main considerations? Treatment plans?
How are we going to transport the patient and what will the definitive treatment likely to be?
Considerations at this point?
SSS
Safety, Scene, Situation
Access & Egress
Safe access and egress
Considerations at this point.
Does Louise appear to be a time-critical patient
What course of action would you take at this point? E.g. back-up, crowd control, focused primary assessment ABCDE
We will come back to Louise late in this session
The prevalence of anaphylaxis has been hard to estimate due to:
Individuals never actually informing their doctor about the reactions they have experienced
Difficulties with definition e.g. (hives without any other manifestations)
Epidemiological surveys suggest reaction to insect stings in 1% of children and 3% of adults
Food allergy is more common in children than adults
Food induced anaphylaxis is estimated to occur in 1%-3% of children
Drug reactions are also common with anaphylaxis occurring in approx. 1% of adults.
Radiocontrast media causes anaphylaxis in 0.1% of procedures performed
Allergen immunotherapy injections cause systemic symptoms in 10%-15% of treated patients, but anaphylaxis is estimated to occur in 3% of cases
Various estimates suggest that 5% of adults may have a history of anaphylaxis
The UK incidence of anaphylactic reactions is rising.
Autopsy findings in anaphylaxis vary from widespread severe pathological findings of pulmonary edema, gastrointestinal hemorrhage, myocardial infarction and severe head and neck angioedema to no pathologic signs.
The risk groups associated with anaphylaxis are:
Asthmatics: Given the complexities of asthma as primarily a condition affecting breathing it stands to reason that if a patient with a history of poorly managed asthma develops an acute overreaction to a particular allergen, breathing is likely to be affected more severely.
Mast Cell Disease: Although rare Mast Cell disease should be considered. AKA Mastocytosis, increased number of mast cells in the bodies tissue. When mast cells detect an allergen, they release histamine and other chemicals into the bloodstream. Histamine makes the blood vessels expand and the surrounding skin itchy and swollen. There are 2 types of mast cell disease:
1 Cutaneous
2. Systemic – generally associated with a heightened reaction to an allergen and subsequent anaphylaxis
Family History: If you have a family member who’ve experienced exercise-induced anaphylaxis, your risk of developing this type of anaphylaxis is higher than it is for someone with no family history.
Age: Anaphylaxis can occur at any age. Figures however suggest that the highest treatment rate for anaphylactic shock is administered to boys aged 12-17 months. Severe food allergy is more common in children than adults. However, the frequency in adults may be increasing, since severe food allergy often persists into adulthood.
Sex: Studies suggest that there may well be a female predominance to the presentation of anaphylaxis outlining that anaphylaxis to IV muscle relaxants, aspirin and latex are more common in women, whereas insect sting anaphylaxis is more common in men. Again these sex discrepancies are a likely function of exposure to frequency.
Referring back to Louise’s case and during your primary assessment your findings are as follows.
Louise has significant angioedema that is causing significant dyspnoea. Her respiration rate is 33 and shallow and she has widespread wheezes across all aspects of her lungs, she is hypoxic at 89% SpO2 on air.
She was very weak palpable radial pulses that are fading rapidly and her blood pressure is 88/52. Louise is profoundly hypotensive.
Louise is also presenting with sinus tachycardia on the 12 lead ECG
With the vital signs listed what are your immediate concerns? Is louise suffering from life-threatening anaphylaxis?
So what next?
Primary Assessment will need to be completed in a timely fashion: this process should take no more than 90 seconds
Airway Patency
Breathing assessment including FLAPS TWELVE
Circulation: CRT, radial pulse check, 1 on the floor 4 more
Disability: GCS, Pupil Check, Blood Pressure
Evaluation
Secondary assessment may take place en route to hospital or once the patient has received initial treatment for life threatening ABCD issues.
This will consist of a full head to toe physical assessment of the patient taking into account:
Abdominal assessment
Skin assessment
Assessing long bones and extremities
Head, eyes and neck
Adrenaline should be considered as soon as you suspect that anaphylaxis. The timely administration of adrenaline (epinephrine) can make the difference between life and death in some cases.
NOTE: A patient may carry their own adrenaline injector (Epipen) this may well have already been administered by your patient prior to your arrival. If no improvement can be seen then the patient must either re-administer a further dose of their own Epipen if available. Or the clinician must administer the required dose.
Some patients may present with recurrent reactions (bipahsic syndrome) several hours after apparent resolution of the initial sings and symptoms, Biphasic anaphylaxis has been reported between 4% and 20% of cases. Signs and symptoms experienced during the recurrent phase may be equivalent to, or worse than, those associated with the initial reaction.
Protracted anaphylaxis or (persistent anaphylaxis) may also occur and may not respond to treatment with glucocorticosteroids. Since life-threatening manifestations may recyr, it may be necessary to observe patients for up to 12 hours after apparent recovery from anaphylactic episodes.
Life threatening:
Asthma can present with very similar symptoms to anaphylaxis
Wheeze/crackles
Dyspnoea
Shortness of Breath
Reduced oxygen saturations
Talking in broken sentences
Acute onset
Sepsis or Systemic Inflammatory Response Syndrome (SIRS) also presents with similar markers
Tachycardia
Shortness of Breath (depending on the manifestation)
Tachypnoea
Confusion
Flushing
Hypotension
Pulmonary Embolism (PE)
Breathlessness
Chest tightness
Tachycardia
Collapse
Choking:
Inability to talk
Noisy or difficult breathing
Collapse
Early administration of IM adrenaline
Aggressive fluid management
