When to Seek Urgent Care: Red Flags and Decision Pathways

Purpose: Red Flags and Decision Pathways

This chapter helps you decide how urgent a temperature-related illness may be and what level of care is appropriate: self-care with monitoring, contacting a clinician the same day, or calling emergency services. The key skill is recognizing red flags that signal possible organ stress, dangerous temperature changes, or complications that can worsen quickly.

Three Levels of Action

Universal Red Flags (Heat or Cold): Call Emergency Services

If any of the following occur, treat it as an emergency regardless of whether the trigger was heat or cold:

• Confusion, unusual behavior, inability to answer simple questions
• Fainting or repeated near-fainting
• Seizures
• Chest pain, severe shortness of breath, or new irregular heartbeat sensation
• Persistent vomiting or inability to keep fluids down
• Signs of shock: pale/clammy skin, weak rapid pulse, severe weakness, blue/gray lips, very low responsiveness
• Worsening symptoms despite first aid (or no improvement within a reasonable window)

Practical check: If the person cannot safely drink, cannot stand/walk without collapsing, or cannot be reliably observed, escalate to emergency care.

Decision Tree: Heat Illness (Self-care vs Clinician vs Emergency)

Use this pathway after you have moved the person to a cooler place and started basic cooling and rest.

Heat Illness Decision Tree (Text-Based)

START: Person exposed to heat and has symptoms (cramps, heavy sweating, weakness, headache, nausea, dizziness, etc.)  ──► 1) Check for EMERGENCY RED FLAGS: confusion, fainting, seizures, chest pain, persistent vomiting, shock, worsening despite first aid  ──► YES → CALL EMERGENCY SERVICES  ──► NO  ──► 2) Suspect HEAT STROKE? (altered mental status, collapse, very ill appearance, hot skin, symptoms escalating fast)  ──► YES → CALL EMERGENCY SERVICES (treat as heat stroke)  ──► NO  ──► 3) Can the person drink and keep fluids down?  ──► NO → CALL EMERGENCY SERVICES (or urgent evaluation if advised locally)  ──► YES  ──► 4) Are symptoms improving within ~30–60 minutes of cooling/rest?  ──► NO or worsening → CONTACT A CLINICIAN SAME DAY (or urgent care); consider EMS if deterioration  ──► YES  ──► 5) Any higher-risk factors? (older adult, pregnancy, heart disease, kidney disease, diabetes, prior heat illness, on diuretics/anticholinergics/stimulants, alone/no supervision)  ──► YES → CONTACT A CLINICIAN for advice even if improving  ──► NO → SELF-CARE + MONITOR for recurrence for the next 24 hours

How to Use the Heat Tree: Step-by-Step

• Step 1: Screen for red flags immediately. Do a quick orientation check: ask name, location, and what day it is. Any confusion is an emergency sign.
• Step 2: Decide if heat stroke is possible. If mental status is abnormal or the person looks severely ill, do not “wait and see.”
• Step 3: Assess hydration tolerance. If repeated vomiting prevents drinking, dehydration and electrolyte problems can escalate quickly.
• Step 4: Time-based reassessment. If cooling and rest are working, you should see clear improvement. Lack of improvement is a reason to escalate.
• Step 5: Adjust for risk. The same symptoms can be more dangerous in people with chronic illness or medication effects.

Examples (Heat)

• Self-care + monitor: A healthy adult with dizziness and heavy sweating after outdoor work who improves steadily after cooling and drinking, and remains fully alert.
• Contact a clinician: Symptoms improve but the person is on a diuretic and has heart disease, or symptoms linger beyond an hour despite appropriate cooling.
• Emergency: The person becomes confused, faints, has persistent vomiting, develops chest pain, or deteriorates after initial improvement.

Decision Tree: Cold Illness (Self-care vs Clinician vs Emergency)

Use this pathway after you have moved the person to shelter and started safe rewarming and dry clothing/insulation.

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Cold Illness Decision Tree (Text-Based)

START: Person exposed to cold/wet/wind and has symptoms (shivering, numbness, clumsiness, fatigue, etc.)  ──► 1) Check for EMERGENCY RED FLAGS: confusion, fainting, seizures, chest pain, persistent vomiting, shock, worsening despite first aid  ──► YES → CALL EMERGENCY SERVICES  ──► NO  ──► 2) Suspect MODERATE/SEVERE HYPOTHERMIA? (confusion, very drowsy, not shivering, slurred speech, poor coordination, cannot walk, very cold trunk)  ──► YES → CALL EMERGENCY SERVICES  ──► NO  ──► 3) Frostbite concern?  ──► If blistering, skin turns hard/waxy, deep numbness, gray/blue/black areas, or large area involved → EMERGENCY SERVICES or urgent ED evaluation  ──► If mild superficial symptoms only and improving with protection → proceed  ──► 4) Is the person improving within ~30–60 minutes of shelter + rewarming?  ──► NO or worsening → CONTACT A CLINICIAN SAME DAY (or urgent care); consider EMS if deterioration  ──► YES  ──► 5) Any higher-risk factors? (older adult, very young child, intoxication, diabetes, thyroid disease, malnutrition, homelessness, on sedatives, alone/no supervision)  ──► YES → CONTACT A CLINICIAN for advice even if improving  ──► NO → SELF-CARE + MONITOR; avoid re-exposure

How to Use the Cold Tree: Step-by-Step

• Step 1: Screen for red flags. Confusion or extreme sleepiness in the cold is particularly concerning.
• Step 2: Decide if hypothermia is beyond mild. Inability to walk, altered speech, or reduced alertness suggests moderate/severe hypothermia and needs emergency evaluation.
• Step 3: Evaluate frostbite severity. Blistering or deep tissue involvement (hard, waxy skin; persistent numbness; color changes) warrants urgent medical assessment.
• Step 4: Reassess response to rewarming. Mild cold stress should improve with shelter and warming. Lack of improvement is a reason to escalate.
• Step 5: Consider supervision and comorbidities. People who are intoxicated, elderly, or medically fragile can decline even after initial warming.

Examples (Cold)

• Self-care + monitor: A hiker with shivering and cold hands who becomes warm, coordinated, and fully alert after shelter and warming, with no skin blistering.
• Contact a clinician: A person who is warmer but still unusually fatigued and unsteady after an hour, or has diabetes and foot numbness after cold exposure.
• Emergency: Confusion, inability to walk, very drowsy state, or frostbite with blistering/hard waxy skin.

Worsening Despite First Aid: What “Escalate” Looks Like

Escalate to a higher level of care if you observe any of the following patterns:

• Symptoms intensify after initial cooling/rewarming (e.g., increasing headache, increasing lethargy, new vomiting).
• New red flags appear (confusion, fainting, seizures, chest pain).
• Relapse: the person improves briefly but then deteriorates again within the next few hours.
• Inability to maintain safe monitoring: the person is alone, cannot be observed, or cannot follow instructions.

What to Tell Responders (EMS, Urgent Care, Clinic)

Having clear information speeds correct treatment. Use this checklist when calling emergency services or speaking to a clinician.

Responder Information Checklist

• Exposure details: where they were, ambient conditions (hot/humid; cold/wet/windy), and estimated exposure time.
• Timeline: when symptoms started and how they changed (improving vs worsening).
• Current symptoms: include any red flags (confusion, fainting, seizures, chest pain, vomiting) and functional status (walking normally vs unable to stand).
• First aid already done: cooling/rewarming steps attempted, fluids given (type and approximate amount), and response to those measures.
• Medical conditions: heart disease, kidney disease, diabetes, thyroid disease, pregnancy, prior heat/cold illness, recent infection.
• Medications/substances: diuretics, beta blockers, anticholinergics, stimulants, sedatives, alcohol or other substances (if known).
• Hydration/urination: whether they can drink, whether they are vomiting, and last urination if relevant.
• Skin findings (cold injuries): location, color changes, numbness, blistering, hard/waxy feel, size of area involved.

Quick Script You Can Read on the Phone

“I’m with an adult/child who was exposed to [heat/cold] for about [X] minutes/hours. Symptoms started at [time] and now include [list]. They are [alert/confused], [able/unable] to walk, and have [vomiting/chest pain/fainting/etc.]. We have already done [cooling/rewarming steps] for [X] minutes and symptoms are [improving/not improving/worsening]. Medical history includes [conditions] and medications include [list if known]. Our exact location is [address/landmark].”

Decision Support: When in Doubt

• Choose safety over certainty. If you are debating between clinician vs emergency and the person is deteriorating, choose emergency services.
• Prioritize mental status. Confusion or reduced responsiveness is one of the strongest indicators that urgent evaluation is needed.
• Prioritize trajectory. A stable person who is clearly improving can often be monitored; a person who is flat or worsening needs escalation.