Wednesday, January 27, 2016

Mysteries of Laura: Giving Insulin

The NBC detective show Mysteries of Laura might need a new medical consultant. In one of the first episodes of this season we have a boy that's been kidnapped and of course-- he's a diabetic in need of insulin or he'll die in short order.

Cut to scenes of distraught parents wringing their hands wondering if the police will get there in time to administer the life-saving medication.

Of course, when they find the young boy, he is unresponsive. One quick insulin shot into his leg and within mere seconds-- he's awake and crying.

This doesn't happen in real life.

The first thing to understand about why the medical approach to this scenario is bad is to understand why a diabetic who doesn't have their insulin gets sick. In a Type I diabetic, their body doesn't produce insulin. Insulin is what moves sugar from your bloodstream to the inner part of your cells for energy so they can function. When there is a lack of insulin, the sugar can't move from the outside to the inside of the cells and that's not a good set-up for sustaining life.

As a rescue measure, the body begins to metabolize fat and muscle for energy. The byproduct of this type of metabolism leads to a build up of acids in the blood called ketones. You can also get a build up of ketones in the blood from not eating carbs as well. When you do this, even though you may produce insulin, your body still perceives a starvation state and will enter into the same process.

In the case of the diabetic, the sugar is "stuck" in the bloodstream which is why they have high blood glucose levels. However, the reason a diabetic is so sick is not really from the high blood sugar-- it is really from the build up of acid in the blood from the break down of fat and muscle. This is also known as diabetic ketoacidosis or DKA. The more acidic a diabetic's blood is when they seek medical treatment-- the more emergent the condition.

So, in this episode we can assume that the diabetic is in DKA. The question is how long does it take to reverse this process?

In a nutshell-- hours-- not minutes. If a diabetic comes in unconscious then it will take them some time to regain consciousness after treatment is instituted to lower the acid levels in the blood and of course, by also lowering blood glucose levels.

What would have been a realistic medical scenario for this episode would be for the boy to have trouble with hypoglycemia or low blood sugar. Or, to have it be that the criminals were giving insulin but giving too much of it.

When a patient's blood sugar is too low, we give glucose IV. In this instance, an unconscious patient WILL wake up very quickly because glucose (sugar) given IV becomes immediately available to the cells for processing and a patient can and will wake up very quickly.

You can still be dramatic using an accurate medical scenario.

Wednesday, January 20, 2016

Injury by Arrow

Jocelyn Asks

I’m now writing a book set in French colonial New Orleans, the years 1720-1722, and we’ve got some drama with the natives.

My MC gets hit with an arrow from someone who isn’t a very good marksman. Can I have him get the arrow in his chest without killing him? Like, if the angle is wrong, or if it wasn’t going super fast? I want the heroine to cut the arrowhead out of his chest, but I also want him to live. If he does survive, how long until he can get up and walk around?

Finally, I want to give him another scar from a previous arrow. Would he have survived an arrow passing through his side, by his waist? Or should I have an arrow skim across his ribs without penetrating? That would leave a scar, right?

Jordyn Says:

You can have an arrow hit a person’s chest without it killing them. It would all depend on where and how deep the arrow hit the individual. The faster the speed the more deeply the object will penetrate tissue. For instance, if I tap you with a bullet clenched between my fingers versus firing it from a gun—much different injuries.

The deeper an arrow is embedded in the chest, particularly the upper chest (where all the great vessels are) the more likely you are to do major, unsurvivable damage considering your era. To answer this question more fully, I’d want to know the size of the arrow. How long and wide is it? I would think anything measuring an inch or more would be worrisome for nicking something important like a large blood vessel or the lung. The way around this might be to have the person be fairly overweight and the arrow gets embedded into fat tissue. This might not be a good option for your hero.

As with all things—the person could just be lucky and the arrow hits but misses all vital structures. I would show this in your text by the character not bleeding heavily or having any difficulty breathing. That would allude to the fact that nothing major has been hit.

If it is merely a “flesh wound” and the arrow comes out in a fairly uncomplicated manner and no infection sets in then the character should have some mild to moderate muscle pain and soreness and perhaps some inhibited movement based on this but should be able to walk fairly immediately.

Someone can survive an arrow passing through the side of their waist, again, if it doesn’t hit any major organ. You have very vascular organs in your abdomen. The liver that sits under the right ribs and the spleen that sits under the left ribs. So, the lower the injury the better. Then you would just need to worry about perforating the intestines which would ultimately lead to sepsis and death but your intestines are housed under the fat layer and other tissues so could be fairly easily avoided. Any injury that requires stitches to approximate (get the edges close together) the wound will leave a scar so even a skimming injury that splits the skin will leave evidence of injury.

Wednesday, January 13, 2016

Use of Animal Tranquilizer Guns in Humans

David Asks:

In my new work in progress I have a woman shot with a tranquilizer gun. She is a former head ER nurse and is on the road. She has a well stocked medical kit. What would she have that could be injected to counteract the tranquilizer? Is there a particular tranquilizer they would use on her? They want her alive.

Jordyn Says:

Thanks so much for sending me your question.

This is an interesting question that you ask. The first part that should be answered is what kinds of drugs are generally used in animal tranquilizer guns. I was fairly surprised to see some of the same drugs we use in humans like opiates (Morphine and Fentanyl.) Interestingly, it looks from this article that the opioid compound used is called M99 which is 10,000 times more potent than morphine and one drop is lethal to humans. It is reversible with a drug called Narcan or naloxone.

A second class of drugs that is used in humans also used in animal tranquilizer guns are the benzodiazepines. For humans these would be drugs like valium, ativan and versed. There is a reversal agent for this class of drugs as well. We call it flumazenil.

Two other drugs were listed in the article. Another drug that we use in humans was a substance that is related to ketamine but does not have a reversal agent. The last, azaperone, which is not familiar to me as a drug used in humans and is also not reversible.

If your ER nurse had a well stocked medical kit then she would have the drug naloxone on hand to reverse an opiate drug if that was used in the tranquilizer dart. What's both interesting and sad about naloxone is that it is becoming readily available to the public because of the drug problem in the USA. So, even if your ER nurse didn't have a well stocked medical kit she could probably find some as long as the dart didn't immediately kill the victim. Opiates cause death by inhibiting your respiratory drive. You simply stop breathing. There are certainly other effects but this is the primary one.

The other drug, flumazenil, that reverses benzodiazepines isn't as readily available so that might not be a great choice for your story.

It's also important to note that from the article, just as in humans, a combination of drugs might be used. So, naloxone might reverse the opiate but not whatever else is in the syringe. Also, animal darts are likely loaded with more medication that would be more likely to produce toxic and dangerous effects to a human than say a bear.

I hope this answers your question and good luck with your novel!

Wednesday, January 6, 2016

How Would You Fake Lab Results?

I feel like I'm going to owe an apology to How to Get Away with Murder as this will be the second time I've called them out in the last couple of months for medical inaccuracies-- or let's just say my personal issues with some of the medical stuff they're floating out there.

You can see my first issue here.

One of the male characters in How to Get Away with Murder, Nate, has a wife who is terminally ill with cancer and wants help committing suicide. She first approaches Annalise Keating, the lead character and attorney to help her get her hands on some pills that will do the trick. And why wouldn't Annalise? She is after all sleeping with her husband.

Over the course of a couple episodes, Annalise does get her hand on some pills, actually gives them to the husband who then gives them to his wife who does commit suicide. Actually, it is a little unclear to me who gives her the pills but the husband is accused of murdering his ill wife.

Unfortunately for Nate, there's a district attorney who's been gunning for him and would like nothing more than to see him in jail. So, even though the wife has been cremated, there's some residual blood left over that she wants tested for the presence of this drug.

Nate approaches a sympathetic hospice nurse to switch out the blood samples so the drug doesn't show up.

Well, probably not very realistic and I'll tell you why.

Keep in mind the whole set up for this trade out is that the blood is already in the lab and the patient is deceased. This part of the scenario is actually plausible. Labs do hang onto specimens after patient's die for a number of reasons.

The first thing to know about labs is it's the one place nurses do not go. I've never been inside a lab-- except on a tour. There's generally a door where you can drop off specimens but you're generally not permitted to enter. So, how does this nurse gain access to the specimen to switch it out?

One, it's going to be odd for a nurse to be snooping around the lab. I mean, notably odd. That's something a lab tech is going to remember.

The other issue is the labeling of the specimen. Even if the nurse gained access to the lab, found the specimen, and was going to replace it (say with her own blood)-- she would need a new label back dated to the time of the "real" specimen. You can hand write out labels but this is very rarely done and I think would raise suspicion as well.

So, the only great way to switch out blood to keep the drug tainted blood from the lab is to do it at the time of collection. Someone draws blood from another person that they know has "clean" blood and puts the patient's label on it. Unfortunately, this isn't a possibility because the patient has died.

There is a way to work this scenario to have it be more realistic-- I just don't think this is the best way.