FIELD REFERENCE
Full criteria & treatment guidance
Key cautions & base contact
- Use the longer 30–45 second pulse assessment specified for apparent hypothermic arrest.
- Do not merge ordinary bradycardia treatment into the hypothermic-with-a-pulse pathway.
Patient with a pulse
- Remove wet clothing, cover to conserve heat, and initiate available active warming. Monitor and document the rhythm.
- Expect a slow heart rate and weak pulse. The thermal order directs against trying to reverse hypothermic bradycardia in the field.
Apparent arrest
- When not obviously dead, assess for a pulse for 30–45 seconds before initiating CPR. If no pulse is detected, follow the adult cardiac-arrest standing order.
- Assist ventilation with BVM without hyperventilation. Continue warming and limit unnecessary interruptions in resuscitation.
Contact and transport
- Contact base when further stabilization orders are needed. The hypothermia pathway directs against field pronouncement.
- Provide transport to the nearest ERC, with ALS escort for the apparent-arrest branch. Continue monitoring for rhythm and perfusion changes.
Handoff
- Report environmental exposure, wet clothing, initial and serial pulse findings, warming measures, arrest/ROSC times if applicable, and all resuscitation treatment.
- Keep the thermal diagnosis visible during handoff so the slow rate is not mistaken for an unrelated routine bradycardia presentation.
VISUAL FIELD REFERENCE
Hypothermia: pulse present or apparent arrest?
Adult / adolescent · ALS
The longer pulse check belongs to the hypothermic apparent-arrest pathway.
Pulse present
Remove wet clothing, cover to conserve heat, and initiate available active warming. Monitor and document the rhythm.
Expect a slow heart rate and weak pulse. The thermal order directs against trying to reverse hypothermic bradycardia in the field.
- 30–45 seconds
Apparent arrest
When not obviously dead, assess for a pulse for 30–45 seconds before initiating CPR. If no pulse is detected, follow the adult cardiac-arrest standing order.
Assist ventilation with BVM without hyperventilation. Continue warming and limit unnecessary interruptions in resuscitation.
- Contact base when further stabilization orders are needed. The hypothermia pathway directs against field pronouncement.
Selected checkpoints; read the complete guide for criteria, exclusions, doses, and ongoing care. SO-E-025
UNDERSTAND THE CARE
Why cold exposure changes the pulse assessment
The thermal order anticipates a slow heart rate and weak pulse. A deliberate pulse assessment is therefore central when arrest is uncertain. Keep the environmental history visible in the team discussion so the slow rate is not automatically treated as ordinary symptomatic bradycardia.
Applying the guidance
Continue warming while monitoring rhythm and perfusion. If no pulse is found after the specified assessment, use the cardiac-arrest pathway and avoid hyperventilation. Report the duration and findings of the pulse check, warming measures and any arrest or ROSC timeline. The source directs against field pronouncement in the hypothermia pathway.
Putting it together
Teaching example: a cold, wet patient has an extremely slow rhythm and a difficult-to-detect pulse. Communicate the thermal context and complete the deliberate pulse assessment before categorizing the patient as pulseless.
Diagram text & teaching checkpoints
- Exposure
- Cold and wet clothing.
- Pulse assessment
- Allow the specified longer assessment.
- Branch
- Pulse present versus apparent arrest.
- Continuing care
- Warming, monitoring and transport.
Sources for this explanation
Original OCMedic teaching synthesis of the references below. Educational expansion updated ; this is not a new independent clinical-review date. Source-specific dates and limitations remain in the full guidance.