What are the immediate treatments for various medical emergencies, including cardiac arrest, anaphylaxis, acute myocardial infarction, and stroke?

Immediate Treatment for Medical Emergencies

Cardiac Arrest

For cardiac arrest, immediately initiate high-quality CPR with chest compressions and rescue breathing, establish ECG monitoring to identify the rhythm, and administer epinephrine 1 mg IV/IO every 3-5 minutes while treating reversible causes. 1

Initial Response

• Begin chest compressions at a rate of 100-120/min with a depth of at least 2 inches, allowing complete chest recoil between compressions 1
• Provide rescue breathing with a compression-to-ventilation ratio of 30:2 for single rescuers 1
• Attach an automated external defibrillator (AED) or manual defibrillator as soon as available 1
• Establish IV or intraosseous (IO) access for medication administration 1

Rhythm-Specific Treatment

• For ventricular fibrillation/pulseless ventricular tachycardia: Deliver immediate defibrillation at 200 joules (biphasic) or 360 joules (monophasic), followed by 2 minutes of CPR before rhythm check 1
• For asystole/pulseless electrical activity: Continue CPR, administer epinephrine 1 mg IV/IO every 3-5 minutes, and aggressively search for and treat reversible causes (the H's and T's) 1

Critical Pitfall

Do not interrupt chest compressions for more than 10 seconds except for rhythm analysis and defibrillation 1. Prolonged interruptions significantly reduce survival rates.

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Anaphylaxis

For anaphylaxis, immediately administer epinephrine 0.3-0.5 mg intramuscularly into the anterolateral thigh, repeating every 5-15 minutes as needed, while simultaneously securing the airway and providing supplemental oxygen. 1, 2

Immediate Interventions

• Administer epinephrine 0.3-0.5 mg (0.3-0.5 mL of 1:1000 solution) intramuscularly into the anterolateral aspect of the thigh 1, 2
• For children weighing ≤30 kg: give 0.01 mg/kg (maximum 0.3 mg) intramuscularly 2
• Repeat epinephrine every 5-15 minutes if symptoms persist or recur 1, 2
• Place patient supine (or in position of comfort if respiratory distress) and administer high-flow oxygen 1

Alternative Routes When IV Access Available

• If IV access is established, consider epinephrine 0.05-0.1 mg (0.5-1 mL of 1:10,000 solution) IV bolus for anaphylactic shock 1
• IV infusion of epinephrine at 5-15 μg/min is reasonable for recurrent shock or postarrest management 1

Airway Management

• Immediately refer to a provider with advanced airway expertise, as oropharyngeal or laryngeal edema can develop rapidly 1
• Emergency cricothyroidotomy or tracheostomy may be required if airway obstruction develops 1

Cardiac Arrest from Anaphylaxis

• If cardiac arrest occurs, prioritize standard resuscitative measures (CPR) with immediate epinephrine administration 1
• Continue standard ACLS protocols while treating the underlying anaphylaxis 1

Critical Pitfall

Never inject epinephrine into buttocks, digits, hands, or feet due to risk of tissue necrosis 2. Doses less than 0.5 mg may paradoxically worsen bradycardia 3.

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Acute Myocardial Infarction (STEMI)

For suspected STEMI, obtain a 12-lead ECG within 10 minutes of arrival, immediately administer aspirin 160-325 mg orally and sublingual nitroglycerin (if blood pressure permits), and activate reperfusion therapy with a goal of door-to-balloon time <90 minutes or door-to-needle time ≤30 minutes. 1, 4

Immediate Assessment (Within 10 Minutes)

• Obtain 12-lead ECG immediately upon arrival—ST-segment elevation ≥1 mm in contiguous leads indicates need for immediate reperfusion 1, 4
• Establish continuous ECG monitoring to detect arrhythmias 1, 4
• Assess vital signs, with particular attention to blood pressure and heart rate 1

Initial Pharmacotherapy

• Aspirin: 160-325 mg orally (chewed for faster absorption) 1, 4
• Nitroglycerin: 0.4 mg sublingual every 5 minutes (contraindicated if systolic BP <90 mmHg or heart rate <50 or >100 bpm) 1, 4
• Morphine sulfate: 2-4 mg IV for pain relief, repeated as needed 1
• Oxygen: Only if arterial oxygen saturation <90% 4

Reperfusion Strategy Selection

• Primary PCI (preferred): If available within 90 minutes of first medical contact, transport directly to PCI-capable facility 1, 4
• Fibrinolytic therapy: If PCI not available within 90 minutes and symptom onset <12 hours, administer fibrinolytic with door-to-needle time ≤30 minutes 1, 4
• Greatest mortality benefit occurs when reperfusion initiated within first hour of symptom onset (35 lives saved per 1000 treated vs. 16 lives saved when given 7-12 hours after onset) 1

Special Considerations for Cardiac Arrest with STEMI

• Patients with cardiac arrest and ST-segment elevation should receive primary PCI as the preferred reperfusion strategy 4
• Targeted temperature management is indicated for patients remaining unresponsive after resuscitation 4

Critical Pitfall

Do not delay reperfusion therapy to wait for cardiac biomarker results 1, 4. Time is myocardium—every 30-minute delay in reperfusion increases mortality.

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Stroke

For suspected acute stroke, immediately assess time of symptom onset, obtain non-contrast head CT to exclude hemorrhage, and if ischemic stroke is confirmed within 4.5 hours of onset, administer IV alteplase while simultaneously activating the stroke team for potential endovascular therapy.

Immediate Assessment (Time-Critical)

• Establish exact time of symptom onset or last known normal—this determines treatment eligibility 5
• Perform rapid neurological assessment using standardized stroke scale 5
• Obtain non-contrast head CT immediately to differentiate ischemic from hemorrhagic stroke 5
• Check blood glucose, as hypoglycemia can mimic stroke 5

ABCDE Approach for Critically Ill Stroke Patients

• Airway: Assess patency and protect if Glasgow Coma Scale <8 5
• Breathing: Provide supplemental oxygen if SpO₂ <94% 5
• Circulation: Establish IV access, monitor blood pressure (permissive hypertension in ischemic stroke unless BP >185/110 mmHg and thrombolysis planned) 5
• Disability: Assess neurological status and pupillary response 5
• Exposure: Check for signs of trauma or other injuries 5

Treatment Considerations

While specific stroke treatment protocols were not detailed in the provided guidelines, the systematic ABCDE approach applies to all critically ill patients including stroke victims 5. The emphasis is on rapid assessment, airway protection, and immediate transport to a stroke-capable facility.

Critical Pitfall

Never administer aspirin or anticoagulation until hemorrhagic stroke has been excluded by imaging. Blood pressure management in acute stroke differs from other emergencies—avoid aggressive BP lowering in ischemic stroke unless specific thresholds are exceeded.

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Key Organizational Principles Across All Emergencies

Prehospital Care

• Emergency medical systems must have trained personnel with physician-directed protocols 1
• Critically ill patients (cardiac arrest, repetitive ventricular arrhythmias, shock) should be transported to facilities with cardiac catheterization and surgical capabilities if transport time is not excessive 1
• Community education about recognizing emergency symptoms and activating emergency services is crucial 1, 4

Emergency Department Management

• Patients with suspected life-threatening emergencies must be identified immediately upon arrival 1
• ECG monitoring should begin at time of entry 1
• Administrative procedures (insurance verification) must never delay emergency treatment 1
• Emergency department physicians should initiate definitive therapy without waiting for consultation if this would cause significant delay 1