Considerations for Heat-Related Illness

Posted by Patrick Lickiss on Aug 23, 2010 in Assessment, Current Events, Treatment | 0 comments

THE CALL
You are dispatched to a private residence at 1430 hrs for an 80 year old female, unresponsive per the reporting party.  As you arrive on scene, you are brought into the back yard of the residence by a neighbor.  During the walk, she hurriedly tells you that she checks on the patient from time to time because she doesn’t have any family in the area.  When there was no answer at the front door, she walked around back to get the spare key and found the patient lying face down on the lawn.  Since the patient didn’t wake up when shaken, the neighbor called 911.

As you approach the woman, she does not track your movements; taking manual c-spine precautions, you roll the woman over on her back.  You find her minimally responsive to painful stimulus with a GCS of 5.  The patient appears to be maintaining a patent airway and has good tidal volume.  As you work on your primary assessment, you find that the patient is hot to the touch with dry skin.  It’s been warm today, but not overly so.  You finish a basic assessment and comfortably rule out spinal immobilization based on a lack of trauma and no obvious mechanism to suspect injury.  With the patient on oxygen you extricate her to the ambulance.  Initial vital signs are BP – 60/40, HR – 140, RR – 36.  What do you do next?

INTRODUCTION
If you’ve been watching the news recently, you know that there have been heat waves across the country.  With record-setting temperatures due for the Bay Area in the next few days, I thought it would be a good opportunity to review treatment and special considerations for heat related injuries.

HEAT-RELATED ILLNESSES
The two types of heat-related illness are heat exhaustion and heat stroke.  Heat exhaustion presents as sweating, dizziness, weakness, headache, nausea and tachycardia brought on by an inability of the body to effectively cool itself with an increased environmental temperature.  Heat stroke, on the other hand, presents with dry, hot skin, altered level of consciousness, shortness of breath and vomiting.  Heat stroke is a significant medical emergency but is easily treated in the prehospital setting.  Both heat-related illnesses are exacerbated by activity and factors like clothing, medical condition and medications.

Patients at higher risk for a heat-related emergency include the elderly and patients with psychiatric conditions, diabetes and obesity and those with alcohol on board or who are dehydrated.  Patients taking certain medications, including those for high blood pressure and seizures, diuretics and illegal drugs like cocaine are also at increased risk for hyperthermia.  One particular drug of note is the SSRI class of antidepressants.  As detailed in the SSRI Overdose article these drugs reduce the ability of the body to cool itself.

For those of us working with disadvantaged populations, many homes do not have air conditioning or are poorly insulated (I’m looking at you, bungalow-style homes!).  In many homes with A/C, the residents simply cannot afford to run the air conditioning.  These homes, during a heat wave, can easily reach 110°F or more indoors.

TREATMENT OPTIONS
As with most environmental emergencies, the first step is to remove the patient from the hazardous environment.  For heat-related illnesses, this means moving the patient into a residence (if it has an air conditioner)or into the ambulance.  If your rig A/C is anything like mine, it takes a few minutes to start blowing cold air.  Since this is the case, I’ll start the A/C at the beginning of my shift to make sure that the back is nice and cool on days that are predicted to be hot.  On the flip side, if a patient is cold when we place them in the back, it doesn’t take long for the patient compartment to warm back up.

After moving the patient, clothing should be loosened, the patient’s legs should be elevated and venous access should be obtained.  For patients suffering from heat stroke, treatment (aside from the obvious airway and breathing management) includes wetting the skin to accelerate cooling, applying ice packs to the core and aggressive fluid resuscitation.  Ice packs should be applied to the neck, axillae and groin, all locations where major arteries come close to the surface.  This allows the blood to be cooled and then circulated throughout the body, cooling from the inside out.  Care must be taken to keep the patient from shivering.  Shivering is the body’s mechanism for warming itself and obviously counteracts the cooling measures being taken.

For patients suffering from heat stroke with altered mental status or signs and symptoms of shock, rapid transport to the hospital is indicated.

COMMUNITY EDUCATION
Many communities set up “cooling stations” on days which are predicted to be hot.  These stations are generally public buildings which have the air conditioning cranked and water available.  By giving people a place to sit, relax and cool off, the hope is that heat-related illnesses can be avoided.  Pay attention to your local news and try to make note of the locations of these stations so you can pass the information on to the public.

One of the best ways to reduce the need for emergency services in your community on hot days is to do your part to teach self-care techniques.  By being aware of personal risk factors, keeping hydrated and staying inside on hot days, potential patients can ride out warm days without needing transport.

SPEAKING OF SELF-CARE
We, as EMS providers, are great at taking care of patients, but sometimes not so great at taking care of ourselves.  Remember that we’re at risk for heat-related illness as well.  Since hot days are busy days and you’re running around carrying patients up and down the stairs with little time to stop (probably wearing heat-absorbing navy blue), you probably aren’t focusing on staying healthy yourself.  With a few changes to your routine, however, you can cut your risk significantly.  First of all, remember that the giant coffee you got at Starbucks this morning is a diuretic, placing you at risk for dehydration.  Add to that the two Rockstars and little water and you’re in pretty poor shape already.  Fill up a water bottle at the beginning of the shift and actually drink it.  I shoot for two quarts during a 12 hour shift and that seems to keep me adequately hydrated.  Also, remember that dark colored urine, or not urinating at all are indications of dehydration.  Try to find shady places to post when you can and consider writing your documentation in the hospital instead of outside in the ambulance.  Lastly, keep that A/C going and remember that “toughing it out” with an A/C that isn’t working in your ambulance is a risk to both you and your patients; so make sure it works when starting your shift.

CONCLUSION
With your patient extricated to the ambulance and active cooling measures in place, you start two IV’s and give her a 500cc bolus.  With ice packs placed, the patient’s level of consciousness steadily improves.  During transport, she becomes alert and oriented.  She tells you that she didn’t have breakfast this morning and only had a cup of coffee.  She remembers going out to work in her garden and estimates that she was outside for 3 hours before her neighbor came to check on her.  With a fluid bolus in, her follow-up vital signs are BP – 118/60, HR – 98, RR – 18.  She is treated at the emergency department, admitted for a 23 hour observation and discharged home with no long term complications.

So with a few hot days coming in the Bay Area and around the country, take the steps needed to keep both you and your communities safe.  By effectively managing risk factors and keeping cool and hydrated, we can all make it through the hot season with as few transports for heat-related illnesses as possible.

OTHER RESOURCES
CDC Extreme Heat Tips

American Red Cross – Heat Related Illness

California Department of Industrial Relations