Emergency Flashcards
Anaphylaxis
-Severe, life-threatening allergic reaction
• Not all allergic reactions will cause anaphylaxis
• Severe allergic reactions can lead to anaphylaxis
– Chemical cascade causes the body to go into shock
– Type I Reaction (IgE)
• Mediated release of histamine and others from mast cells and basophils
– Occurs from seconds
Signs and symptoms/diagnosis of anaphylaxis
– General appearance/vital signs
• Restless and anxious
– Dermatological
• Generalized or local erythema, urticaria, cutaneous injection or pruritis, warmth, angioedema
– Ocular
• Conjunctival injection, pruritis, ecchymosis
– Cardiovascular
• Hypotension & weak and rapid pulse
– Respiratory
• Congestion, coryza, rhinorrhea, sneezing, throat tightness, wheezing, hoarseness, dyspnea
Gastrointestinal
• Nausea, vomiting, diarrhea, bloating, cramps, dysphagia
– Neurological
• Dizziness, headache, blurred vision, syncope, seizure, depressed level of consciousness, agitation, combative, altered mental status
– Other
• Metallic taste, feeling of impending doom
Causes of anaphylaxis
Food allergies
• Peanuts, tree nuts, fish, shellfish, milk
– Medications
• Antibiotics, aspirin, OTC pain relievers, IV contrast
– Venom
• Bees, yellow jackets, wasps, fire ants, hornets – Material
• Latex, plastics
– Activity
• Aerobic exercise (jogging)
Risk factors for anaphylaxis
-Previous anaphylaxis
– Allergies or asthma
– Heart disease
– Mastocytosis (accumulation of specific white blood cell)
Differential diagnosis for anaphylaxis
-Vasovagal* – Hereditary angioedema – Malignant carcinoid syndrome – Medullary thyroid carcinoma – Pheochromocytoma – Systemic mastocytosis
Testing for anaphylaxis
-Serum tryptase
• Confirm diagnosis – Urinary 24h histamine
• Diagnose recurrent anaphylaxis – Urinary 24h 5-hydroxyindoleacetic acid level
• R/O malignant carcinoid syndrome – In vitro IgE tests/skin tests
• Determine food, medication, and causes of IgE-independent reactions
Managment of anaphylaxis: non pharmacological
- Airway management (ventilator with bag/valve/mask/intubation)
- High-flow oxygen
- Cardiac monitoring and pulse oximetry
- IV access
- Fluid resuscitation with isotonic crystalloid solution
- Supine position with legs elevated
Pharmacological managment of anaphylaxis
• Adrenergic agonist – Epinephrine • Antihistamines – Diphenhydramine, hydroxyzine • H2 receptor antagonists – Cimetidine, ranitidine, famotidine • Bronchodilators – Albuterol •Corticosteroids – Methylprednisolone, prednisone • Positive inotropic agents – Glucagon • Vasopressors – Dopamine
Surgical management of anaphylaxis
- Cricothyrotomy
* Catheter jet ventilation
In office management of anaphylaxis
- Call 911
- Use an Epipen
- Lie the patient down with legs elevated** (Why? Get blood to brain. If not they will go into a full blown seizure)
- Administer albuterol and then oxygen
- Check pulse/breathing and perform CPR if needed
Vasovagal syncope
-Also called neurocardiogenic syncope or reflex syncope
– Response is controlled by the vagus nerve (CNX)
• Breathing, sweating, regulating heart rate, emptying food from stomach
• Involuntary body functions are controlled by parasympathetic nervous system
– Certain triggers inducing extreme stress leading to syncope
• Triggers → bradycardia/hypotension/hyperhidrosis → reduced blood to the brain → syncope
Signs and symptoms/diagnosis of vasovagal syncope
-General appearance/vital signs • Jerky, abnormal movements – Dermatological • Pale skin, felling of warmth, cold/clammy sweat – Ocular • Dilated pupils – Cardiovascular • Hypotension & weak and slow pulse – Respiratory • Yawning -Gastrointestinal • Nausea, vomiting – Neurological • Dizziness, tunnel vision, lightheadedness, blurred vision, syncope
Causes of vasovagal syncope
- Excessive standing
- Heat exposure
- Seeing blood or needles
- Having blood drawn
- Fear of injury
- Straining
- Tonometry
- Bright lights
Differential diagnosis of vasovagal syncope
– Anaphylaxis – Cardiac syncope (unknown cause of syncope have a 30% increase in death vs vasovagal have no increased risk of death) – Hemorrhage – Pulmonary embolism – Carotid sinus hypersensitivity – Orthostasis – Medications – Metabolic – Seizure
Testing for vasovagal syncope
– Electrocardiogram – Echocardiogram – Exercise stress test – Blood tests – Neurological studies – Tilt table (done after heart problems are r/o)
Non pharm management of vasovagal syncope
- Foot exercises
- Compression stockings
- Increased salt intake
- Increased fluid intake
Pharmacological managment of vasovagal syncope
• Beta-blockers
– Atenolol
• Counteracts the increase in serum epinephrine that occurs before syncope
• Mineralocorticoids
– Fludrocortisone acetate
• Treats hypotension
• Selective serotonin reuptake inhibitors
– Fluoxetine
• 5HT inhibits sympathetic neural outflow while increasing adrenal sympathetic stimulation
• Vasoconstrictors
– Disopyramide
• Decrease cardiac contractility and manages heart rate
Surgical management of vasovagal syncope
Electrical pacemaker
In office management of vasovagal syncope
- Try to catch patient before they fall
- Lie the patient down with legs elevated
- Check pulse/breathing
- Administer smelling salt
Orbital compartment syndrome
– Rare but treatable complication of increased pressure within the orbital space
– Mostly secondary to facial trauma or a surgical procedure
Anatomy of orbital compartment syndrome
– Globe and retrobulbar contents are in a cone-shaped fascial envelope bound by 7 bony
walls (except anteriorly in which the boundary is the orbital septum and eyelid).
– The medial and lateral canthal tendons attach the eyelids to the orbital rim
• Limits forward movement of the globe
Pathophysiology of orbital compartment syndrome
– Increased tissue pressure in an enclosed space → decreased perfusion
• Pressure within the orbit exceeds the pressure of the central retinal artery → ischemia
Causes of orbital compartment syndrome
– Causes • Trauma – After large-volume resuscitation, asphysxia syndrome • Surgery/procedures – Extravasated contrast material, complications of spinal surgery in prone position – Spontaneous bleeding • Infection • Tumor • Inflammation – Graves
Retrobulbar hematoma
• Most common cause of OCS
• Hemorrhage emanating from infraorbital artery/branch
• Most commonly occur as an ophthalmologic/maxillofacial postop
complication
• Retrobulbar blood causes large increase in pressure unless
decompressive drainage occurs (through orbital wall fractures into the
paranasal sinuses)
• Causes an anterior ischemic optic neuropathy
