Therapeutic Hypothermia: Part 2/2

Last post I discussed a little bit about situations where therapeutic hypothermia might be indicated.

This post I thought I’d discuss exactly how it’s done. The highlighted points came from this article. It focuses on a research protocol for adults but is a nice jumping off point for scene writing if you wanted to do this for one of your characters.

The type of adult who would be eligible:

1. Adult resuscitated from witnessed arrest from cardiac cause. This is important because then the down time is known and the likelihood of preserving good brain function is more likely versus just prolonging a vegetative state.
2. They are comatose and intubated (on a breathing machine.)
3. Initial rhythm of v-fib/v-tach– which are lethal heart rhythms that require electricity for conversion to a normal perfusing rhythm. 
4. Have a stable blood pressure after resusitation.

Not eligible:

1. Temperature less than 86 degrees Fahrenheit. This is probably because you are really dead.
2. Pregnancy.
3. Terminal Illness.
4. In a coma prior to arrest.
5. Inherited blood clotting disorder.

How do you cool?

1. Insert a core temperature monitor (into the bladder, heart, or esophagus.)
2. Infuse 20-30cc/kg of normal saline cooled to 39.2 degrees Fahrenheit over 30 minutes.
3. Maintain temperature at 89.6- 93.2 degrees Fahrenheit for 24 hours with cooling blankets.
4. Use sedation as needed and paralytics if the patient is shivering– the point of this would be that shivering causes expenditure of energy and we wouldn’t want that to happen.
5. Nursing care includes lubricating eyes, monitoring urine output, watching blood sugars closely.
6. Rewarm the patient 0.3-0.5 degrees at a time.
7. Don’t provide nutrition during this phase– I’m assuming they mean putting food into someone’s gut which makes sense as it wouldn’t be getting good blood flow and would just sit there undigested causing problems.

What do you think? Would you ever use therapeutic hypothermia in a scene?

You can further read the article for more in-depth information.

The Four Day Frozen Baby: Therapeutic Hypothermia 1/2

In the last couple of months, I recently heard a news story about the “Baby Frozen for Four Days”. I don’t know what it is, perhaps it’s the suspense author in me, but I immediately began to imagine those that have had their heads disconnected from their body and frozen until a point in time comes where they can be attached to another disease free body.

And just what happens to those other people who “donate” a whole body without their head? I’m sure there is a suspense novel in there somewhere. Probably already has been.

But I digress. Instead, I’ll keep the vision of Hans Solo in my mind.

Therapeutic hypothermia is actually a reasonable therapy to consider when the medical staff is concerned about potential brain damage.

But to say the patient is frozen is a little bit of a misnomer. If the tissue were truly frozen it would crystallize and be damaged– this would not benefit the patient.

Instead, the body temperature is dropped to around 33 degrees Celsius or 91.4 degrees Fahrenheit. Normal body temperature is 37 degrees Celsius or 98.6. Next post will discuss how this might be accomplished.

Generally, therapeutic hypothermia is used when there is a concern for brain injury, usually after an anoxic event, which means the patient potentially suffered from a lack of oxygen.

Common situations where this could occur would be during birth (for infants) and after cardiac arrest (for adults) which is currently how the therapy is employed. It came out recently to consider therapeutic hypothermia in instances of pediatric arrest though it’s not widely employed at this time.

The reason therapeutic hypothermia is effective is that it slows brain metabolism and protects brain tissue from oxygen free radicals which are release during tissue injury.

In recent news, however, there were two different instances where infants were placed in therapeutic hypothermia. One was after repair of a complex heart defect where perhaps the infant did arrest or was on bypass for longer than desired– though this is speculation and not stated in the article. Case two was an infant that had a very fast heart rhythm called SVT and I’d not heard of using hypothermia anywhere as treatment for this heart condition.

All very interesting.

So keep therapeutic hypothermia in mind for use in fiction after a patient suffers cardiac arrest as I did in my recently released novel Peril— it will definitely add to the tension.

Check out the follow links to read more about therapeutic hypothermia:

1. Infant who had heart surgery.
2. Infant with SVT.
3. Use of hypothermia in infants post traumatic delivery.