immunological emergencies in paramedic practice

Question 1

Thunderstorm Asthma Key Facts:

Answer 1

21 November 2016
• 1358: 35⁰c, BoM issues severe weather warning (thunderstorms, winds, hail) for Western Victoria
• No evidence to suggest severe asthma likely
• Onset 1700 - 1800 in West of Melbourne
• 1900-1915: 201 emergency ambulance requests
• 2000: 100 Code 1 responses pending dispatch
• Highest ever ambulance demand
• Police and fire brigade enlisted to respond to medical emergencies
Ambulance managers used in response capacity
• Hospitals running out of salbutamol
• Ambulance responding code 1 to branches for oxygen
• 10 patients subsequently died
• Majority of MICA requests not fulfilled

Question 2

Asthma History taking:

Answer 2

• Questioning
o Time of onset
o Severity compared to other episodes
o Medication regime (relief?)
o Prodrome
o PHx ICU / ETT
o Recent ED / ambulance attendance

• Assessments
o Full clinical approach
o 12L ECG
o SpO
2 – unreliable indicator of severity
o Conscious EtCO2 monitoring?
•Differential diagnosis
o Anaphylaxis
o AECOPD
o APO
o Bronchiolitis
o UAO

Question 3

Acute Asthma Management:

Answer 3

Mild or moderate exacerbation
o pMDI
salbutamol

Severe exacerbation
o Nebulised salbutamol and ipratropium
o Oral / IV corticosteroid (prednisolone / hydrocortisone / dexamethasone)
o IM adrenaline if unimproved / worsening

Critical exacerbation
– above Mx plus
o Consider need for APPV
– slow ventilations, long expiratory time
o IV adrenaline (infusion if available, low dose)
o IV magnesium, IV aminophylline (bronchodilators)
o NIV – CPAP /
BiPAP (controversial, scarcely available prehospital)
o Consider DFI –ketamine (bronchodilator) + paralytic
o Mechanical ventilation w/ I:E ratio 1:3 -5 (normal 1:2)
o Chest decompression

Question 4

Asthma management - Pharm:

- Salbutamol pharmacology:

Answer 4

β2 adrenergic agent that causes smooth muscle relaxation = bronchodilation

Question 5

Asthma management - Pharm:

- Ipratropium

Answer 5

Anticholinergic agent that blocks
bronchoconstricting
- causing parasympathetic ANS tone and allow increases bronchodilating
- causing sympathetic tone to maximise

o Acts synergistically with salbutam

Question 6

Asthma management - Pharm:

- Corticosteroids (prednisolone/ hydrocortisone/dexamethasone etc)

Answer 6

o Inhibit inflammatory response
o Benefits over longer term, hospital duration, representation
etc

Question 7

Asthma management - pharm:

- Ketamine

Answer 7

o NMDA receptor antagonist that causes dissociation
o Sympathomimetic that causes some degree of bronchodilation
o Preferred agent for DFI of asthmatic patient

Question 8

Asthma management - pharm:

- Adrenaline

Answer 8

o α1 effects cause vasoconstriction to overcome raised intrathoracic pressure and
increase preload
o β2 adrenergic effects cause bronchodilation
o β2 effects mediate degranulation of mast cells and histamine release

Question 9

RASH criteria - Anaphylaxis:

Answer 9

sudeen onset of symptoms (minutes to hours)
AND
two or more of RASH with or without comfirmed antigen exposure.
- R = respiratory distress (SOB, Wheeze, cough, stridor)

• A = Abdominal symptoms (nausea, vomiting, abdo pain/cramps + diarrhoea)
• S = skin/mucosal symptoms
  (hives, itch flushing, swollen lips/tongue)
• H = Hypotension (or altered conscious state)
  OR
• isolated hypotension (SBP < 90) following exposure to known antigen)

Question 10

Anaphylaxis management:

-

Answer 10

• Early identification of possible anaphylaxis
• IM adrenaline as first line agent regardless of severity
• Do not stand the patient (next slide)
• High flow oxygen (why?)
• Once IM adrenaline given and established, consider life threatening problems
  o Hypotension: normal saline fluid resuscitation
  o Bronchospasm: salbutamol +/- ipratropium
  o Airway angioedema: nebulised adrenaline
• IV access for all presentations
• Intensive care backup for sick patients / non-responsive to adrenaline
  o Glucagon if β -blocked and non responsive to adrenaline
  o IV adrenaline therapy, IVI preferred
• Transport for all patients regardless of resolution
  o Biphasic anaphylaxis (4 hour observation period minimal)
  o Protracted anaphylaxis
• Steroids no longer indicated

Question 11

Sepsis:

Answer 11

• systemic inflammatory disorder
• Mostly bacterial sources
• major morbidity and mortality (higher than storke and AMI)
• At risk groups
  o Immunosuppressed
  o Elderly
  o Children
• Difficult to screen for
  o No prehospital validated scoring systems
  o Difficult in hospital

Question 12

SIRS

SEPSIS

SEVERE SEPSIS

SEPTIC SHOCK

Answer 12

SIRS criteria: as above (BP substituted for WCC in hospital)
Sepsis = SIRS criteria + actual or suspected infection
Severe sepsis = sepsis + organ dysfunction
Septic shock = sepsis + hypotension refractory to fluid administration

Question 13

Sepsis management:

Answer 13

1. Recognition
   • Largest mortality benefit likely recognition in less unwell patients
2. Transport
   • Appropriate destination for sick patients (ICU / HDU)
   • Appropriate action plan with safety netting for less sick patients
3. Oxygen therapy
   • Target SpO2 >93% for most patients
   • High flow O2 for septic shock
4. Fluid administration for poor perfusion
   • Renal protective
   • Problems and risks specific to sepsis?
5. Inotropic / vasopressor therapy
   • Adrenaline or noradrenaline IV infusion
   • Limited to ICPs
   • High doses possibly needed – side effects?
6. Intubation
   • Risky due to pathophysiological processes
   • Limited to ICPs –reluctant procedure

Question 14

Febrile Neutropenia management:

Answer 14

Any febrile
chemotherapy patient
• Immediate emergency
transport
• Manage for sepsis
symptomatically
• Consider aseptic
techniques
• Destination may
require consult