View Full Version : Hypothermia & Hypovolemia

12-13-2008, 02:23
I have a question just to throw out there for discussion.

Q: Can a state of permissive hypothermia used in conjunction with a state of permissive hypotension slow the process of shock down enough to buy time to control hemorrhage from a non-compressible bleeder site (i.e. places you cant get a tourniquet).

It's a research project I undertook to keep myself busy when it's slow. I honestly think it sounds better in theory than it actually is given that hypothermia + trauma = increased mortality. There aren't a lot of clinical trials that I know of to base it on, only research from textbooks etc. What do you M.D.'s and Operators think?
The questions I am trying to answer in the research project are;
Is is possible?
Is the risk worth the gain?
What would the treatment protocol be (theoretically)?

12-13-2008, 04:56
the problem is that hypothermia associated with shock from hypovolemia usually is associated with acidosis....the hypothermia also contributes to coagulation disorders and the combination of hypothermia/acidosis/coagulopathy is known a the lethal triad....leading to dead patients. We do everything possible to maintain normothermia in the face of hypovolemia/shock....hence damage control (abreviated) surgical procedures....try google and you'll read all about this concept.
So, the moral of the story is right theory, wrong clinical entity to try it on.


Red Flag 1
12-13-2008, 07:01

Hypothermia, and deliberate hypotension are not uncommon in the operating room. Both have benefits in patient outcome in practiced hands. As SS points out, there are complications with hypothermia; complications with hypotension no less dangerous.

I have experience in planned hypotension for blood loss reduction, and planned hypothermia. They are planned, closely (beat to beat ) monitored, and reversable at our descretion. I do not see a way to replicate this control in the field. Perhaps in time it may be possible, just don't see it anytime soon.

RF 1

12-13-2008, 11:10
Just a small add to what has already been mentioned. As a a point of practice, while working in trauma centers (Syracuse and Seattle), when our trauma teams were alerted the trauma SGN would come in and crank the thermostat in the trauma room. We were all sweating buckets as the patients would come in all shivers. Hypothermia was actively combated in our level I trauma patients in order to minimize that portion of "the triad" SS mentioned.


12-13-2008, 15:19
I can attest to sweating buckets in the ER and seeing a patient shivering like crazy, even in the summers in Iraq.

My initial answer to my own question was: no way. Outside of an OR where it can be meticulously controlled, it is probably not the best idea. It would only exacerbate an already critical situation.
But I got a little hung up on the fact that cold organs have less of a o2 and nutrient demand, and that in the earlier stages of hypothermia the metabolic processes slow down, which would lead me to believe the onset of acidosis would also be slower. Hence maybe buying a little time to keep progressive shock at bay.

I agree with SS, decent theory, not very practical in the operational setting.

12-14-2008, 13:16
We keep the trauma bays here a bit toasty around 78 degrees for the reasons Eagle mentioned.

I recently read a review article that indicated that one degree C of hypothermia increased transfusion requirements in surgical patients. Now this was looking at mild hypothermia, so perhaps it was enough to cause a slight coagulopathy but not cold enough to induce a great deal of vasoconstriction. Still, food for thought.
http://www.ncbi.nlm.nih.gov/pubmed/18156884?ordinalpos=37&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum


12-14-2008, 16:00
I was under the impression permissive hypothermia was to be used in cases of medical cardiac arrest. Permissive hypotensive management with lower MAP's are used in the management of trauma. I have yet to read any studies or even see in anecdotal instances of practice the two being mixed in hypovolemic hemmorhagic states. I would think this would be a fool hearty endeavor in the oft 'untenable and uncontrolled' environment of the field as aforementioned above.

Intuitively one would think they'd at least want to have central access with at least a cortis as well as a some other precision monitoring equipment that isn't really available in the civilian EMS world outside of some aeromedical programs and CCT services. I can't speak for the 'military side' of things and there are others much better equipped to do so here than I.