NREMT EMT 3: Secondary Assessment - Vital Signs Measurement and Interpretation, Blood Pressure, Pulse Oximetry, EtCO2

What This Is: Vital Signs Measurement and Interpretation

Vital signs measurement and interpretation is a critical skill for EMTs and laypeople to assess a person's condition in an emergency. It's like checking the dashboard of a car to see if everything is working properly. Imagine you're at a party and someone suddenly collapses – you need to know if they're breathing, bleeding, or in cardiac arrest.

Key Steps / Core Facts

• Blood Pressure (BP): measures pressure in blood vessels; normal range is 90-120/60-80 mmHg; high BP can lead to heart attack or stroke.
  • (Use the "5-1-1" rule: 5 seconds to take the first reading, 1 minute to take the second reading, and 1 minute to take the third reading.)
• Pulse Oximetry (SpO2): measures oxygen levels in blood; normal range is 95-100%; low SpO2 can indicate respiratory distress or cardiac arrest.
  • (Look for "normal" or "low" SpO2 readings – if it's low, start oxygen therapy.)
• End-Tidal CO2 (EtCO2): measures carbon dioxide levels in exhaled breath; normal range is 25-35 mmHg; low EtCO2 can indicate cardiac arrest or respiratory failure.
  • (Use the "normal" or "low" EtCO2 readings – if it's low, start CPR.)
• Pulse: measures heart rate; normal range is 60-100 beats per minute (bpm); irregular pulse can indicate cardiac arrhythmia.
  • (Count the pulse for "10 seconds" and multiply by "6" to get the bpm.)
• Respiratory Rate (RR): measures breaths per minute; normal range is 12-20 breaths per minute; high RR can indicate respiratory distress.
  • (Count the breaths for "10 seconds" and multiply by "6" to get the RR.)
• Temperature: measures body temperature; normal range is 97.7-99.5°F (36.5-37.5°C); high temperature can indicate fever or heatstroke.
  • (Use a "digital thermometer" or "oral thermometer" to take the temperature.)
• Mental Status: assesses level of consciousness; normal range is alert and oriented; altered mental status can indicate head injury or stroke.
  • (Use the "AVPU" mnemonic: A – alert, V – verbal, P – pain, U – unresponsive.)
• Pain Assessment: assesses level of pain; normal range is no pain; high pain can indicate injury or illness.
  • (Use the "OPQRSTI" mnemonic: O – onset, P – provocation, Q – quality, R – region, S – severity, T – timing, I – intensity.)
• Red Flags: look for danger signs such as:
  • Severe bleeding
  • Difficulty breathing
  • Cardiac arrest
  • Severe pain
  • Altered mental status

What Laypeople Can Do

• If someone collapses, first check for danger (oncoming traffic, fire). Then shout and tap their shoulder.
• If someone is having trouble breathing, help them sit up and use an inhaler (if prescribed).
• If someone is in cardiac arrest, call 911 and start CPR (30 chest compressions, 2 breaths).

Common Mistakes

• Mistake: Not taking multiple blood pressure readings.
• Fix: Take "3" readings, 1 minute apart, to get an accurate reading.
• Mistake: Not using a pulse oximeter.
• Fix: Use a "pulse oximeter" to get an accurate SpO2 reading.
• Mistake: Not assessing mental status.
• Fix: Use the "AVPU" mnemonic to assess level of consciousness.

Quick Practice Scenarios

1. A patient is having trouble breathing and has a SpO2 reading of 80%. What should you do first?
2. A patient is in cardiac arrest and has a pulse of 10 bpm. What should you do first?
3. A patient is having severe pain and has a temperature of 104°F (40°C). What should you do first?

Answers:

1. Start oxygen therapy.
2. Start CPR.
3. Administer pain medication.

Last-Minute Exam Cram

• Normal vital sign ranges: BP 90-120/60-80 mmHg, SpO2 95-100%, EtCO2 25-35 mmHg, pulse 60-100 bpm, RR 12-20 breaths per minute, temperature 97.7-99.5°F (36.5-37.5°C).
• Drug doses: "5-1-1" rule for BP medication, "30:2" ratio for CPR.
• Mnemonics: "AVPU" for mental status, "OPQRSTI" for pain assessment.
• Assessment sequences: "SAMPLE" for patient assessment, "OPQRSTI" for pain assessment.
• Common "trick" questions: Agonal breathing is NOT normal breathing – start CPR.