What are the most common and rare emergency presentations, and what are their characteristic signs, recommended investigations, and initial management including drug dosages?

Emergency Department Presentations: Common and Rare Cases

Most Common Emergency Presentations

1. Acute Coronary Syndromes (ACS) - NSTE-ACS/Unstable Angina

This is one of the most critical and common emergency presentations requiring immediate recognition and treatment.

Signs and Symptoms

• Chest discomfort/pain at rest lasting >20 minutes 1, 2
• Anginal equivalents: shortness of breath, diaphoresis, nausea, lightheadedness 2
• Hemodynamic instability
• Recent syncope or presyncope 1

Investigations

• 12-lead ECG within 10 minutes of arrival 3, 4
• Cardiac troponin (T or I) on arrival and at 10-12 hours after symptom onset 3
• CK-MB mass 3
• Basic metabolic panel, CBC

Management with Doses

Immediate treatment (within minutes):

• Aspirin 162-325 mg chewed (non-enteric coated for faster absorption) 5, 1, 2
• Nitroglycerin sublingual (if no hypotension or recent phosphodiesterase inhibitor use) 3, 1
• Supplemental oxygen if hypoxic 3
• Morphine for pain control 3

Antiplatelet therapy (maintenance):

• Aspirin 81 mg daily (preferred maintenance dose) 5
• Plus one P2Y12 inhibitor for up to 12 months 5:
  • Ticagrelor 90 mg twice daily (preferred over clopidogrel) 5
  • OR Clopidogrel 75 mg daily 5
  • OR Prasugrel 10 mg daily (post-PCI, if not high bleeding risk) 5

Anticoagulation:

• Low-molecular-weight heparin can be started in ED 3

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2. Acute Asthma Exacerbation

Severe exacerbations are potentially life-threatening and require prompt recognition and aggressive treatment.

Signs and Symptoms 6

• Respiratory distress, wheezing (though absence doesn't exclude obstruction)
• Tachycardia (present in 56% of presentations)
• Altered level of alertness
• Inability to speak in full sentences
• Use of accessory muscles

Risk Factors for Death 6

• Previous severe exacerbation requiring intubation/ICU
• ≥2 hospitalizations for asthma in past year
• ≥3 ED visits for asthma in past year
• Using >2 canisters of short-acting beta-agonist per month
• Cardiovascular disease or other chronic lung disease

Investigations 6

• Serial FEV1 or peak expiratory flow at presentation and 30-60 minutes after initial treatment
• Pulse oximetry
• Arterial blood gas if severe
• Chest X-ray to rule out pneumothorax, pneumonia

Management with Doses 6

Immediate treatment:

• Short-acting beta-2 agonist (albuterol) 2.5-5 mg nebulized in 3 mL saline, repeat as necessary
• Systemic corticosteroids (for moderate to severe):
  • Methylprednisolone 1.0-2.0 mg/kg/day IV every 6 hours 6
  • OR Prednisone 0.5 mg/kg orally for less critical episodes 6
• Supplemental oxygen to maintain saturation >90%

For refractory bronchospasm:

• Continue frequent nebulized albuterol
• Consider ipratropium bromide
• Magnesium sulfate (if severe)

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3. Acute Ischemic Stroke

Stroke must be approached as a life-threatening emergency with immediate evaluation.

Signs and Symptoms

• Sudden focal neurological deficits
• Altered consciousness
• Seizures (in some cases)
• Signs of increased intracranial pressure

Investigations

• Immediate CT head (non-contrast) to exclude hemorrhage
• Blood glucose
• Coagulation studies if considering thrombolysis
• ECG, cardiac biomarkers

Management with Doses 7

Within 3 hours of symptom onset:

• rtPA 0.9 mg/kg IV (maximum 90 mg) - strongly recommended if patient meets NINDS criteria 7
  • 10% as bolus over 1 minute
  • Remaining 90% as infusion over 60 minutes

General supportive care:

• Airway protection, breathing support, circulation management 7
• Cautious blood pressure management - avoid aggressive lowering unless extremely elevated 7
• Aspirin 160-325 mg within first 48 hours (if not receiving thrombolysis) 7

Increased intracranial pressure management:

• Osmotherapy and hyperventilation for deteriorating patients with herniation 7
• Corticosteroids NOT recommended for cerebral edema 7
• Surgical decompression for large cerebellar infarctions with brainstem compression 7

Seizure management:

• Treat recurrent seizures as any acute neurological condition 7
• Prophylactic anticonvulsants NOT recommended 7

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Rare but Critical Emergency Presentations

1. Anaphylaxis

This is a life-threatening emergency requiring immediate recognition and treatment.

Signs and Symptoms 8

• Acute onset (minutes to hours)
• Skin/mucosal involvement (urticaria, angioedema)
• Respiratory compromise (bronchospasm, stridor)
• Hypotension, cardiovascular collapse
• Gastrointestinal symptoms

Management with Doses 8

First-line treatment:

• Epinephrine 0.3-0.5 mg IM (1:1000 dilution) in anterolateral thigh - repeat every 5-15 minutes as needed 8
  • This is the MOST CRITICAL intervention

Second-line treatments:

• Diphenhydramine 25-50 mg IV/IM (1-2 mg/kg) 8
• Ranitidine 1 mg/kg IV diluted in D5W over 5 minutes (combination with diphenhydramine superior to diphenhydramine alone) 8
• Albuterol 2.5-5 mg nebulized for bronchospasm resistant to epinephrine 8

For hypotension refractory to epinephrine:

• Aggressive IV fluid resuscitation
• Dopamine 400 mg in 500 mL D5W at 2-20 mcg/kg/min IV, titrated to blood pressure 8

For patients on beta-blockers:

• Glucagon 1-5 mg IV over 5 minutes (20-30 mcg/kg in children, max 1 mg), followed by infusion 5-15 mcg/min 8

Consider corticosteroids:

• Methylprednisolone 1.0-2.0 mg/kg/day IV for severe/prolonged anaphylaxis or patients with asthma 8

Critical pitfall: Delayed epinephrine administration is the most common error. Epinephrine must be given immediately, not after antihistamines.

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2. Cardiac Tamponade

Rapidly progressive and fatal if not recognized and treated emergently.

Signs and Symptoms 9

• Beck's triad: hypotension, muffled heart sounds, jugular venous distension
• Pulsus paradoxus
• Tachycardia
• Dyspnea

Investigations 9

• Emergency echocardiography (transthoracic or transesophageal if TTE non-diagnostic)
• ECG (may show electrical alternans, low voltage)
• Chest X-ray

Management 9

• Immediate pericardiocentesis - this is life-saving
• Aggressive IV fluid resuscitation while preparing for drainage
• Avoid positive pressure ventilation if possible (worsens hemodynamics)
• Surgical drainage if recurrent or loculated

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3. Acute Aortic Dissection

Mortality increases 1-2% per hour if untreated.

Signs and Symptoms 9

• Sudden severe "tearing" chest or back pain
• Blood pressure differential between arms
• Pulse deficits
• Neurological deficits
• Acute aortic regurgitation murmur

Investigations 9

• CT angiography (most common)
• Transesophageal echocardiography
• ECG to rule out MI

Management 10

• Immediate beta-blocker (before vasodilators to prevent reflex tachycardia)
• Target systolic BP <120 mmHg within 20 minutes 10
• Labetalol or esmolol preferred
• Then add nitroprusside 0.5 mcg/kg/min if needed for BP control 10
• Emergent surgical consultation for Type A dissection

Critical difference from other hypertensive emergencies: This requires RAPID blood pressure reduction to <120 mmHg systolic, unlike most other conditions where gradual reduction is preferred 10.

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Key Management Principles Across All Emergencies

Initial stabilization (ABC approach):

• Airway protection and oxygenation
• Breathing support
• Circulation management with IV access
• Continuous monitoring (cardiac, BP, oxygen saturation)

Common pitfalls to avoid:

1. Delaying definitive treatment while obtaining extensive workup
2. Overly aggressive blood pressure reduction in most hypertensive emergencies (except aortic dissection and flash pulmonary edema) 10
3. Failing to give aspirin early in suspected ACS
4. Delaying epinephrine in anaphylaxis
5. Using corticosteroids for cerebral edema in stroke 7

Documentation and follow-up:

• Record all interventions with times
• Serial reassessments every 15-30 minutes in critical patients
• Clear disposition planning
• Patient education on warning signs for recurrence