When should patients call 911 (Emergency Medical Services)?

When to Call 911: Guidelines for Patients

Patients should call 911 immediately for any symptoms that could indicate a life-threatening emergency, particularly chest pain or discomfort that is unimproved or worsening after 5 minutes, as this could represent a heart attack requiring rapid medical intervention. 1

Specific Conditions Requiring 911 Activation

Heart Attack/Chest Pain

• Call 911 immediately for chest pain or discomfort that is unimproved or worsening after 5 minutes, rather than attempting self-transport 1
• For patients previously prescribed nitroglycerin (NTG):
  • Take one dose of NTG for chest discomfort
  • If symptoms are unimproved or worsening 5 minutes after taking NTG, call 911 immediately 1
  • For chronic stable angina patients: if symptoms improve after one NTG, they may take up to 3 doses (one every 5 minutes) but should call 911 if symptoms don't completely resolve 1
• For patients without prescribed NTG: call 911 if chest discomfort/pain is unimproved or worsening 5 minutes after it starts 1
• While waiting for EMS, patients with suspected heart attack may take aspirin (162-325 mg, chewed) if no contraindications exist 1

Stroke

• Call 911 immediately for any signs of stroke, including facial drooping, arm weakness, or speech difficulties 1
• First aid providers should use a stroke assessment system to identify potential strokes 1

Severe Allergic Reaction/Anaphylaxis

• Call 911 immediately for anyone with suspected anaphylaxis or severe allergic reaction 1
• Symptoms include difficulty breathing, swelling (especially of face/throat), hives, dizziness, or vomiting 1
• If prescribed, administer epinephrine while waiting for EMS 1

Hypoglycemia (Low Blood Sugar)

• Call 911 immediately if a person with diabetes is unconscious, having seizures, or unable to follow simple commands or swallow safely 1
• For mild hypoglycemia in conscious patients who can swallow, give glucose tablets or dietary sugars first, but call 911 if symptoms don't improve within 10-15 minutes 1

Unresponsiveness/Cardiac Arrest

• Call 911 immediately for any unresponsive person 1
• If the person is unresponsive with no breathing or only gasping, begin CPR after calling 911 1

Patient Education Recommendations

What Healthcare Providers Should Teach Patients

• Actively discuss with patients their heart attack risk and how to recognize symptoms of acute coronary syndrome 1
• Advise patients to call 911 if symptoms are unimproved or worsening after 5 minutes, despite uncertainty about symptoms or fear of embarrassment 1
• Create a specific action plan with patients for recognizing and responding to potential cardiac events, including the number to call (911) 1
• Instruct family members, close friends, or caregivers to reinforce the importance of rapid action when cardiac symptoms occur 1

Common Reasons Patients Delay Calling 911

• Thinking symptoms will go away on their own 2
• Believing symptoms aren't severe enough 2
• Attributing symptoms to another condition 2
• Fear of embarrassment if it's a "false alarm" 1
• Attempting self-treatment with prescription or non-prescription medications 1
• Thinking self-transport would be faster 2

Benefits of Using 911 vs. Self-Transport

• Patients transported by EMS have shorter time to treatment and better outcomes 1
• Approximately 1 in 300 patients with chest pain transported by private vehicle suffers cardiac arrest en route 1
• EMS personnel can perform life-saving interventions if cardiac arrest occurs 1
• EMS can perform pre-hospital ECGs, which are associated with shorter reperfusion times and lower mortality rates 1

Special Considerations

• All communities should have a written protocol guiding EMS personnel in determining where to take patients with suspected acute coronary syndrome 1
• Patients with known STEMI and/or cardiogenic shock should be transported directly to hospitals with interventional and surgical capability 1
• When calling 911, patients should be prepared to provide location, description of the emergency, number of victims, and type of aid being provided 1
• Callers should stay on the line until the dispatcher instructs them to hang up 1

By educating patients about when to call 911, healthcare providers can help reduce delays in seeking treatment for life-threatening conditions, potentially saving lives and improving outcomes 1.