Hypothermia cardiac arrest use of D50

[RomeViking09]

This week our instructor had the idea to break up a chapter on environmental emergencies and make us in groups of two teach the 4 sections of the chapter. First hats off to anyone who preps and teaches paramedic students on a regular basis. Second I was teaching the section on cold related medical emergencies and covered just hypothermia (my partner for the assignment covered all the "others" and had only about 1/3 of the stuff to cover given the powerpoint provided by the instructor and the amount of stuff in the textbook). We had a good debate over dealing with hypothermic cardiac arrest that I want to bring to the forum.

When dealing with a patient in cardiac arrest the textbook says not to administer any drugs until you have warmed the patient to at least 86ºF, the point came up that if one of the reasons the body is not thermorgulating is due to lack of glucose should you not give that patient D50 in addition to CPR and warming the patient in an attempt to improve their outcome. What are everybody's thoughts?

[Paramagic]

This week our instructor had the idea to break up a chapter on environmental emergencies and make us in groups of two teach the 4 sections of the chapter. First hats off to anyone who preps and teaches paramedic students on a regular basis. Second I was teaching the section on cold related medical emergencies and covered just hypothermia (my partner for the assignment covered all the "others" and had only about 1/3 of the stuff to cover given the powerpoint provided by the instructor and the amount of stuff in the textbook). We had a good debate over dealing with hypothermic cardiac arrest that I want to bring to the forum.

When dealing with a patient in cardiac arrest the textbook says not to administer any drugs until you have warmed the patient to at least 86ºF, the point came up that if one of the reasons the body is not thermorgulating is due to lack of glucose should you not give that patient D50 in addition to CPR and warming the patient in an attempt to improve their outcome. What are everybody's thoughts?

Hypothermia and particularly cardiac arrest managment in hyopthermia is actually a very poorly studied field (for obvious reasons) What little science there is on hypothermia suggests that CPR until such time as active rewarming is instituted (either extracorporeal or passive) is the way to go. There are case studies of VF resolving on rewarming with no further intervention.

The things to remember with hypothermic patients is that 1) they are very fragile. If they aren't in arrest now, any insult, however slight, will cause them to arrest. and 2) they are essentially hibernating. Their basal metabolic rate is so low that they don't require the same "numbers" that they would normally require to maintain cellular function. The biggest mistake people can make is seeing a low BP, heart rate or resp rate and thinking they need to do something about it.

Now, as to a patient being hypoglycaemic to the point where thermoregulation is impaired, I would suggest that they are in far more dire straights than we are going to be able to rescue them from. Hypoglycemic patients do get cold, mostly because they sweat like a madman, but this is not the same as the actual hypo causing loss of heat regulation. When you think about it, you are saying that the patient has become so hypoglycemic that their brainstem has stopped working. Not a good sign!

So, to cut a long story short... no I would not give D50 to the hypothermic patient. They do not need large amounts of energy as they are in a low energy state and all I would be doing is introducing a thick, hypertonic solution into a bloodstream and body that isn't really going to cope with it and doesn't really need it.

[Doczilla]

D50 is okay. The prohibition on drugs in hypothermia generally refers to proarrhythmic (epi, atropine) or antiarrhythmic (amiodarone, lidocaine) drugs because of the proarrhythmic state of the hypothermic heart. Glucose is important for heat generation once the patient is warm enough to shiver. Hypoglycemia may also contribute to the bradycardia and decreased inotropy.

'zilla

[kohlerrf]

30 years ago we use to give D50 as a matter of course to any cardiac arrest patient, as well as 2 bicarbs and an amp of calcium. this treatment has since fallen out of favor because they have found bad things happen from the dumping in of d50 for no specific reason. if you sampled the blood an found the blood glucose level to be deficient by all means give d50. now a days the thinking is the to start cooling you patient while they are in cardiac arrest and not wait for ROSC. granted there are levels of hypothermia as you mentioned 86% but is it a given that just because some one is cold they are hypoglycemic? I think the primary focus is warming the body so that metabolism in general can take place and then worry about the energy stores. Remember you can only pronounce a warm body dead.

[Job13_5]

The prohibition on drugs in hypothermia generally refers to proarrhythmic (epi, atropine) or antiarrhythmic (amiodarone, lidocaine) drugs because of the proarrhythmic state of the hypothermic heart.

Can you explain this a little more? I.e. the "proarrhythmic state of the hypothermic heart."

[chbare]

I'm not sure it's possible. The biochemistry of hypothermia is exceedingly complicated. A good article on the pathophysiology of accidental hypothermia: http://qjmed.oxfordjournals.org/content/95/12/775.full

A key point should be that hypothermia is not simply a process that "slows" things down. We have to consider concepts such as oxygen extraction, protein confirmation, and so on. So, while an irritable heart does not make sense on an intuitive level, I think it does make sense when considering just how complicated the pathophysiology must be.

Take care,

chbare.

[Kiwiology]

I'm not sure it's possible. The biochemistry of hypothermia is exceedingly complicated.

Why must everything come back to bloody [bio]chemistry .... I knew I should have taken it!

[Riblett]

Yikes! Biochem sucks. Here is my quick and dirty summation of biochemistry as it relates to temperature and EMS pharmacology ....the bodily activities are designed to be carried out at normal body temperature. That is the condition in which all the body chemicals (enzymes, substrates, binding agents, etc) work most efficiently. When that is thrown out of whack, enzymes may be deactivated, carriers on the surfaces of the cells may not function properly, cellular channels may not open/close normally, ion movement may be inhibited, and receptors/receptor sites may change shape to where things don't fit together as nicely as before. Metabolism, thermo-regulation, and cardiac conduction rely heavily on these types of processes. That being said, most of the pharmacological agents designed to effect these processes in the body may not work properly in extreme hypo or hyperthermia.

I would not condone arbitrarily giving D50 to help with thermo-regulation because you are loading them up with a viscous and necrotizing substance. But if the patient's blood sugar is low, I would say give them the D-50. With their metabolic processes already hindered, don't make them cope with another set back of an unacceptably low glucose level.