18 yo heat stroke discussion

[RocketMedic]

I'm simply stating to not withhold transport. Do not attempt to "fix" the pt on scene and then transport. Everything can be done en route. If the pt had only water to drink or is a "salty sweater" hyponatremia is a real possibility. The only way to know is through labs... at a hospital. Also, without knowing CK you can't treat for rhabdo prophylactically. Unless in the setting of crush syndrome or you actually witness myoglobinuria. None of which was mentioned. I would (and have) placed the pt on the stretcher, initiate transport, direct AC vents at the pt, strategically place ice packs, place in Trendelenburg if appropriate, start a IV, administer fluids if in 250ml bolus if appropriate, and administer O2 if appropriate.

Remember, this is a military medic. A lot of our treatments are 'mission-driven', meaning that us transporting out immediately might not be possible. Also, remember that we often have providers in relatively-forward locations who might direct us to rehydrate on-site.

For my money, it really depends on the context. If we're on a range in the middle of nowhere, treat while transporting. If we're on a small base with adequate facilities, I'll probably take a shot at treatment onsite.

 

[8jimi8]

Remember, this is a military medic. A lot of our treatments are 'mission-driven', meaning that us transporting out immediately might not be possible. Also, remember that we often have providers in relatively-forward locations who might direct us to rehydrate on-site.

For my money, it really depends on the context. If we're on a range in the middle of nowhere, treat while transporting. If we're on a small base with adequate facilities, I'll probably take a shot at treatment onsite.

We treated onsite at Bonnaroo. Not one single person was transported by ems for heat related illness. The only people who left were those who needed xrays or a helicopter. And let me tell you. We had the BARE minimum of supplies.

 

[Akulahawk]

I'm simply stating to not withhold transport. Do not attempt to "fix" the pt on scene and then transport. Everything can be done en route. If the pt had only water to drink or is a "salty sweater" hyponatremia is a real possibility. The only way to know is through labs... at a hospital. Also, without knowing CK you can't treat for rhabdo prophylactically. Unless in the setting of crush syndrome or you actually witness myoglobinuria. None of which was mentioned. I would (and have) placed the pt on the stretcher, initiate transport, direct AC vents at the pt, strategically place ice packs, place in Trendelenburg if appropriate, start a IV, administer fluids if in 250ml bolus if appropriate, and administer O2 if appropriate.

So... you treat for what you see. Horses, not Zebras. I'm not necessarily advocating for withholding transport. Arranging for transport can result in wait times ranging from nearly zero (you're the transport) to relatively extended. Also, determine the need for transport.

Yes, a big consideration is the setting. If I'm running an aid station all by myself or with limited assistance and no immediate transport, I'd have likely handled this patient in a very similar way. My evaluation would likely have come to the same conclusion: Severe heat exhaustion or Heat Stroke. Begin active cooling measures, arrange for transport, start a line, run in fluid. Continue cooling and determine if the patient is in need of a 2nd line or 2nd Liter of NS. Consult with OLMC if necessary. If I am the transport unit... load the patient ASAP, and begin cooling/fluids.

8jimi8's experience with HS patients is pretty much how fast onset HS should be treated. Cool the patient down, get a liter in 'em, see how they tolerate PO H2O. Small 250 mL boluses won't do much for a patient that is about 2-3 Liters deficient... and most of us "run" about 1 L deficient anyway.

Just 3% loss of body weight can start the problem... at my weight, this is about 6 lbs, about 2.8 liters. A 5% loss is worse. At my weight, that's about a 4.7 liter loss. I'd be well into heat exhaustion at that point. At 7%... I'd be looking at about a 6.4 liter loss, and I'd be in real trouble by then.

Someone that weighs 150 lbs looks about like this:
3% = 4.5 lbs = 2.1 L
5% = 7.5 lbs = 3.5 L
7% = 10.5 lbs = 4.9 L

Heat illness and heat stroke that develops over several days... would not likely be treated this way. Those are the ones that you treat more slowly. Know the patient population and the onset of the heat stroke. The above stuff is for the acute, rapid onset kind... not the kind that develops over several days and people end up baking themselves into it... the elderly are especially vulnerable to that...

 

[jwk]

I just got back from Bonnaroo, where I personally treated over 50 patients for heat exhaustion/stroke.

Standard treatment was IV, room temp normal saline, encourage po h20.

If nauseated refractory to 1l ns and unable to tolerate sips of water 12.5mg phenergan ivp, or 4mg zofran ivp

then a 2nd bag of ns.

respite until nausea subsides, then back to the party once recovery to about 80%. (subjective 80%)

Sounds like cases of heat exhaustion, not heat stroke.

 

[8jimi8]

Sounds like cases of heat exhaustion, not heat stroke.

Yes I should not have included stroke in my posting. Thank you

 

[mycrofft]

Tal and Yotam, thanks for posting!

Our current military trend towards "hydration" (even the use of that term) started in lessons learned from the Yom Kippur War.

Field tx is always a balance between transport over treatment except for treatments done in route. (There's an equation in there somewhere). Also, with military service, you are starting with a healthy bunch but they may be undergoing extremes in exertion and not eating or drinking properly. These in heat can lead to electrolyte imbalance, rhabdo, heat exhaustion. They also tend to rebound rapidly; don't be fooled about the severity of an incident when the 19 y/o supertroop rapidly rebounds, she/he may have been really FUBAR but resuscitation mustered their deep organic reserves. Might flag their records to watch for future episodes.

AKULA, I concurr on the zebras versus horses, and extend it to treatment modes. Often simple quick treatments, especially in this population, will do the trick; overtreatment may only prolong the issue once you take charge of their homeostasis. I've mentioned how on a big chemical warfare exercise the orally resuscitated troops did as well or better than the IV rehydrated troops, in regards to simple heat exhaustion and early dehydration.

 

[usafmedic45]

I can see the utility to protect the airway from febrile seizures

It's not febrile seizures, it's shivering. Big difference, not to mention that reducing the patient's metabolic rate is a goal in reduction of severe hyperthermia.

but they will also lessen the effectiveness of the cooling system, and that can help cache the heat.

Prove it.

I'd rather manage the root cause as noninvasively as possible and introduce the anticonvulsants as needed.

You're still going to be sticking IV's into this guy, so it's not that much more "invasive". Not to mention that the patient is probably already unconscious or at least significantly altered.

 

[J. Burdett]

So you are saying rhabdo and hyponatremia would be considered a ''zebra" in this situation? Electrolyte imbalances and elevated CK/myoglobin go hand in hand with most severe heat exhaustion and/or heat stroke pts. Apples and apples I would say

My point here is that treating aggressively by only what you "see" could lead to a very bad day.

I do not advocate runaway IV's (There is nothing wrong with a 250ml bolus, reevaluate, another 250ml bolus, reevaluate, so on and so forth.) and I also do not advocate delaying transport. I understand the military setting is different and transport may not be readily available but if you have a transport unit available then by all means...... transport.

So... you treat for what you see. Horses, not Zebras. I'm not necessarily advocating for withholding transport. Arranging for transport can result in wait times ranging from nearly zero (you're the transport) to relatively extended. Also, determine the need for transport.

Yes, a big consideration is the setting. If I'm running an aid station all by myself or with limited assistance and no immediate transport, I'd have likely handled this patient in a very similar way. My evaluation would likely have come to the same conclusion: Severe heat exhaustion or Heat Stroke. Begin active cooling measures, arrange for transport, start a line, run in fluid. Continue cooling and determine if the patient is in need of a 2nd line or 2nd Liter of NS. Consult with OLMC if necessary. If I am the transport unit... load the patient ASAP, and begin cooling/fluids.

8jimi8's experience with HS patients is pretty much how fast onset HS should be treated. Cool the patient down, get a liter in 'em, see how they tolerate PO H2O. Small 250 mL boluses won't do much for a patient that is about 2-3 Liters deficient... and most of us "run" about 1 L deficient anyway.

Just 3% loss of body weight can start the problem... at my weight, this is about 6 lbs, about 2.8 liters. A 5% loss is worse. At my weight, that's about a 4.7 liter loss. I'd be well into heat exhaustion at that point. At 7%... I'd be looking at about a 6.4 liter loss, and I'd be in real trouble by then.

Someone that weighs 150 lbs looks about like this:
3% = 4.5 lbs = 2.1 L
5% = 7.5 lbs = 3.5 L
7% = 10.5 lbs = 4.9 L

Heat illness and heat stroke that develops over several days... would not likely be treated this way. Those are the ones that you treat more slowly. Know the patient population and the onset of the heat stroke. The above stuff is for the acute, rapid onset kind... not the kind that develops over several days and people end up baking themselves into it... the elderly are especially vulnerable to that...

 

[Akulahawk]

So you are saying rhabdo and hyponatremia would be considered a ''zebra" in this situation? Electrolyte imbalances and elevated CK/myoglobin go hand in hand with most severe heat exhaustion and/or heat stroke pts. Apples and apples I would say

My point here is that treating aggressively by only what you "see" could lead to a very bad day.

I do not advocate runaway IV's (There is nothing wrong with a 250ml bolus, reevaluate, another 250ml bolus, reevaluate, so on and so forth.) and I also do not advocate delaying transport. I understand the military setting is different and transport may not be readily available but if you have a transport unit available then by all means...... transport.

What I'm saying is that heat stroke brought on during exertion (soldiers, athletes) is a rapid onset problem. That's one reason why you might just see confused mentation, elevated core temp and the patient still sweating.

Also, sweat is hypotonic compared to blood. Yes, you lose electrolytes, but your blood becomes hypertonic as you mostly lose water by sweating. During exercise, you do lose a lot of water... so you become dehydrated. Your sodium level goes up, your fluid goes down, both will drive your thirst, but can take a while to kick in. Hyponatremia won't be a problem. Rhabdomyolysis might become one... due to excessive heat and dehydration. Rhabdo doesn't always happen in Heat Stroke. Remember, this is NOT a case of classic heat stroke.... this is exertional. Intense exercise is also a cause of rhabdo. IMHO, it's very possible to have a patient who is severely dehydrated and early in exertional heat stroke who does not develop rhabdo because the patient is found and treated early. Tx for rhabdo and severe dehydration is the same. Fluid. Tx for exertional heat stroke? Active cooling and fluid...

Being that this is an exertional heat stroke, I'm not all that worried about hyponatremia. I'd be wanting to cool and begin to rehydrate quickly and arrange for transport to definitive care ASAP, but the longer the patient bakes... the worse off. Oh, and I'm not advocating runaway IVs where all I do is swap out liter after liter...

Heat Exhaustion is MUCH easier to treat...

 

[RocketMedic]

It's not febrile seizures, it's shivering. Big difference, not to mention that reducing the patient's metabolic rate is a goal in reduction of severe hyperthermia.



Prove it.



You're still going to be sticking IV's into this guy, so it's not that much more "invasive". Not to mention that the patient is probably already unconscious or at least significantly altered.

Core temps over 102*F can result in febrile seizures (either focal or grand mal), often involving the airway. Calling it 'shivering' is just plain dumb- some patients shiver, but other patients seize.

Reducing the patient's metabolism is a decent idea, but I really don't want to start sedating a patient who's already dehydrated or worse. If they're seizing, that's another story, but I really don't feel comfortable hitting patients who are severely heat-stressed or in the early stages of heat stroke (meaning not seizing) with sedatives.

I think that infusing saline or LR is a great thing, but cooling and transport is probably the best thing that we can do for this patient. Rhabdo and hyponaturemia is a concern, but in this patient, I'd rather treat the dehydration and hyperthermia first, and manage the electrolytes later. As was mentioned above, the treatments are the same anyways. (Also, in this case, the medic has the unique option to treat preventively by managing food and hydration).

Without labs, I really don't feel comfy infusing potassium.

Heat caching is a risk if we depress their respiratory and sweating mechanisms by sedating. We park their heat internally.

 

[mycrofft]

emedicine reference

http://emedicine.medscape.com/article/166320-overview

"EHS is the second most common cause of death among high school athletes, surpassed only by spinal cord injury".

Back to OP about transport versus stay and cool, if you can cool someone enroute, do that.

Our teaching and post-incident reviews tend to overrun the act of multitasking because we try to single out treatments as individual factors, when in fact they are going on simultaneously once in practice. Sort of like learning a piano concerto one hand at a time.

(I'm always amused at the pinpoint measures, such as chemical cold packs to some magic point on the body, some folks espouse to cooling a patient, when, if possible, the simple grosser measures are often as or more effective. If you're stuck in a vehicle or something else limits what you do, then, sure; otherwise, move and/or cool the air, support sweat, remove clothes, and titrate to effect (e.g., stop when the pt feels better and/or starts to develop goosebumps).

 

[J. Burdett]

Yes, exertional heat stroke has a acute presentation.

Yes, Heat exhaustion/heat stroke can cause rhabdo.

Heat exhaustion/heat stroke can also cause hyponatremia. We do not know what the soldier had to drink that day or the consistence of his perspiration. The treatment for hyponatremia is not the same as heat related illness and/or rhabdo. Aggressive rehydration can lead to hyponatremia. Over correction of sodium (hypo or hyper) levels can lead to Central Pontine Demylinolysis. It's a delicate balance.

How about a military study for a military OP ftp://ftp.rta.nato.int/PubFullText/RTO/MP/RTO-MP-HFM-086/ACSM/ACSM-01-Montain.pdf

Transport, B) down, judicious IV therapy.

I'm not saying you are wrong about anything. Everything you have said is golden. I just would have had a different approach to the OP's pt. Different strokes fo different folks!

What I'm saying is that heat stroke brought on during exertion (soldiers, athletes) is a rapid onset problem. That's one reason why you might just see confused mentation, elevated core temp and the patient still sweating.

Also, sweat is hypotonic compared to blood. Yes, you lose electrolytes, but your blood becomes hypertonic as you mostly lose water by sweating. During exercise, you do lose a lot of water... so you become dehydrated. Your sodium level goes up, your fluid goes down, both will drive your thirst, but can take a while to kick in. Hyponatremia won't be a problem. Rhabdomyolysis might become one... due to excessive heat and dehydration. Rhabdo doesn't always happen in Heat Stroke. Remember, this is NOT a case of classic heat stroke.... this is exertional. Intense exercise is also a cause of rhabdo. IMHO, it's very possible to have a patient who is severely dehydrated and early in exertional heat stroke who does not develop rhabdo because the patient is found and treated early. Tx for rhabdo and severe dehydration is the same. Fluid. Tx for exertional heat stroke? Active cooling and fluid...

Being that this is an exertional heat stroke, I'm not all that worried about hyponatremia. I'd be wanting to cool and begin to rehydrate quickly and arrange for transport to definitive care ASAP, but the longer the patient bakes... the worse off. Oh, and I'm not advocating runaway IVs where all I do is swap out liter after liter...

Heat Exhaustion is MUCH easier to treat...

 

[InsidiousStealth]

Those vitals and signs and symptoms sound like heat exhaustion, not heat stroke.

Heat stroke from what I understand the blood pressure will drop and there will no longer be any sweating at all because the body will have exhausted all its available water and sodium. Thus the body can no longer maintain homeostasis because it cannot get rid of excessive heat

With concerns to your question I think that wasn't excessive cooling. Cooling often involves indirect cooling such as sitting in the shade, or removing clothing and that is often longer then 30 mins anyways....

Just my opinion though

 

[Akulahawk]

Those vitals and signs and symptoms sound like heat exhaustion, not heat stroke.

Heat stroke from what I understand the blood pressure will drop and there will no longer be any sweating at all because the body will have exhausted all its available water and sodium. Thus the body can no longer maintain homeostasis because it cannot get rid of excessive heat

With concerns to your question I think that wasn't excessive cooling. Cooling often involves indirect cooling such as sitting in the shade, or removing clothing and that is often longer then 30 mins anyways....

Just my opinion though

RR: 24
HR: 150
Temp PR: 41C\ 105.8F
B.P 150\80
sat: 98%

O2 mask on and cool him down with watter 90 litters apox.
in the clinic I start an IV an at all total he got 2 litters of normal sailine.
the all cooling part took about 30 min, after that;
RR: 16
HR: 105
Temp PR: 38C\100.4F
BP: 120\70

What you're seeing is a patient in heat stroke whose body is still able to compensate somewhat for the loss of fluid. The patient is confused and has an elevated/elevating core temperature. I would imagine that given another hour of baking (and losing fluid via sweat) you'd be seeing him begin to present the more "classic" signs of heat stroke. The heart rate is elevated and the BP is way up in an attempt to maintain adequate perfusion to the organs. What does the body do when it's in shock, before things fall off the cliff into decompensated shock?

Heat exhaustion may show with nausea, vomiting, dizziness... and so on, but the core temperature will not be elevated much above 37C/98.6F. This patient is at 41C/105.8F and if not cooled down soon (which was what happened)... he'll be in a whole lot more trouble.

You might call the state this patient is in "Incipient Heat Stroke" because he's still got some features of heat exhaustion and some features of heat stroke but hasn't crashed yet.

 

[mycrofft]

Two way...electrolytes and heat exhaustroke

If heat exhaustion and heat stroke are two different ailments, why not have both? Or/and, sometimes something does not present with the entire constellation of symptoms yet it is still that porblem..or sometimes a variant. People still argue over "THE CAUSE" of "heat stroke", just like they used to argue over "THE CAUSE" of "CANCER".

Electrolytes...most cases of heat illness I treated included an admission they skipped meals, especially the preceding one or two, or were not eating their entire meals or skipping parts. Generally, they were eating starches and sweets and maybve the main entree, but skipping or skimping from the vegetables. In hot weather, they entrees also got shorted. Nearly NONE of my patients were compliant with eating, and many were noncompliant about drinking water.

 

[Akulahawk]

If heat exhaustion and heat stroke are two different ailments, why not have both? Or/and, sometimes something does not present with the entire constellation of symptoms yet it is still that porblem..or sometimes a variant. People still argue over "THE CAUSE" of "heat stroke", just like they used to argue over "THE CAUSE" of "CANCER".

Electrolytes...most cases of heat illness I treated included an admission they skipped meals, especially the preceding one or two, or were not eating their entire meals or skipping parts. Generally, they were eating starches and sweets and maybve the main entree, but skipping or skimping from the vegetables. In hot weather, they entrees also got shorted. Nearly NONE of my patients were compliant with eating, and many were noncompliant about drinking water.

That happens all the time... especially to people unaccustomed to exercise or unacclimated to the local conditions. Very experienced athletes, this can happen, but it's relatively rare as they've come to realize that keeping hydrated is key to good performance. I've seen a relatively new runner, doing her 1st 5k. It was probably 88F out, low humidity, and sunny. She skipped the water stations at the turn-around and all the way back... She wasn't quite as bad off as the OP's patient was, but she was certainly heading down the same track. She was treated with active cooling measures and a couple liters of NS by on site MD. She ended up just fine. Hopefully she learned her lesson to keep hydrated...

 

[mycrofft]

The Yom Kippur War lesson as related to me.

They noted that they had more heat related training casualties than simulated casualties. Sergeants were held responsible if their troops fell ill and hydration routine was prescribed.

On the other hand, Israeli armed forced specifically targeted water carriers of the enemy, right along with fuel tankers. Impacted them, too.

 

[InsidiousStealth]

Good call! Thanks for the learning. I stand corrected

 

[jwk]

http://emedicine.medscape.com/article/166320-overview

Good review article. They discuss the difference between "exertional heat stroke" and "non-exertional heat stroke".