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Medical help: diagnosing coma + haemorrhage symptoms
Gustav Klimt
ariana_paris wrote in little_details
USA modern day

Hello everyone. Very glad one of my readers pointed me here and I hope someone knowledgeable can help. I wish I'd known about this comm sooner. :)

I'm writing a story in which a character is shot by a poisoned dart containing a man-made poison and falls off a low building. After he is admitted to hospital, apparently just suffering from broken limbs, he falls into a coma, and once the doctors have revived him, he starts to bleed profusely. So much for my made-up symptoms.

I don't really want to steer the conversation in the direction of things that I have already looked up because I am hoping for a rethink, but as it is a requirement, here we go: I started off with researching the causes of the coma, mainly on Wikipedia and

I thought the doctors might try to initially treat it as an infection since the coma occurred in hospital. However, as a dramatic device, one of my betas suggested a hemorrhage, therefore leading me to investigate whether the doctors might think the drugs used for infections (eg: vancomycin) might cause this. Since "thrombocytopenia" is listed as a side-effect under blood disorders in the British National Formulary for most antibacterials, I went and researched that (for example here) and other possible causes of clotting disorders on Wikipedia (particularly how blood Factors work, Vitamin K's involvement and whether the doctors might assume he was taking Warfarin or other Coumarins). One possible cause of thrombocytopenia and a coma is ALF, so I looked up Acute Liver Failure (mainly on Wikipedia) and I'm wondering if the poison could for instance be producing benign tumours that have started to affect his liver function.

The thing is, the doctors don't know about the poison, so what are the most likely conclusions they might draw from the symptoms above? And what would they do to try and treat the symptoms and whatever condition they think it is?

Suggestions for poisons with interesting effects welcome, though since I need the guy to ultimately make a full recovery, I might have to make that bit up and have some magic antidote...

However, my medical knowledge being limited, I'd prefer some informed discussion, particularly of the dead ends the doctors might investigate in the course of normal diagnosing.

Thanks in advance!

Bleed profusely from where?

Comas can be caused by subdural hematomas (obviously among many other things). If you want bleeding into the intracranial space, that might be an option.

Thanks for your response. The bleeding I've mentioned in the story is from the nose and ears, though there is still the option to expand the locations. :) It looks as though they might be able to determine a subdural hematoma from a CT scan and remove it either by draining it with a catheter or by operating. Something to ponder, even if it's just something for the doctors to mention and then eliminate. So thanks!

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I still have some resources from back when I used to write medical fic

I'll admit this intrigued me so I took a sneak peak at your journal. It's, er, probably the same fandom and what's more crossed over with another fandom you seem to be involved in (see icon). Small world. XD Plus your journal also taught me something very relevant about why John shoots right-handed!

I noticed that although it was included mainly for dramatic purposes, it isn't actually illogical for bleeding to occur in conjunction with a coma, so at least I'm reassured I wasn't making up completely illogical symptoms! Thanks for the suggestion about the New England Journal of Medicine. I also followed your suggestion and googled "coma bleeding poison" which yielded the interesting fact that Amatoxins (present in poisonous mushrooms) cause similar symptoms, albeit not quite in the same order.

So lots to think about all around. Thanks!

(Deleted comment)
Talking about the left-handed/right-handedness, incidentally, it has occurred to me that my left-handed son always eats with his right hand. So it's evidently not all that unusual to perform different activities with different hands, in addition to the left/right-eyeness as it were.

I would welcome the list of medical resources. I'm hoping to stay away from medical drama in future, but I have to go where the bunnies hop, so you never know. At least I know there is some backup here if I get stuck again!

As to why I ended up writing a (sort of) medical drama, I saw this fantastic crossover video and couldn't resist. ;)

Edited at 2012-05-05 11:02 pm (UTC)

I'm not a doctor, so I can't help with the differential diagnoses etc, but I am a pharmacist (I specialise in Medicines Information) and I probably wouldn't go down the "benign tumour causing ALF" route. The liver generally has an awesome capacity to cope with things, and it'd probably shrug off a few small benign tumours. Your liver failure would probably have to be more likely to be chemical in nature - along the lines of a paracetamol overdose.

I had been thinking, though, how about a novel poison based on an antidepressant, like a selective serotonin reuptake inhibitor? (SSRI)

Large doses of SSRIs cause "Serotonin syndrome"/toxicity, which can lead to coma (among other things, including dying), as well as shivering, jerkiness etc (which could also explain why he fell off the roof). Serotonin is also responsible for triggering platelet accumulation, and because SSRIs stop your platelets taking up serotonin, it leads to an increased risk of bleeding. (I'm not sure how fast that occurs in real life, but it would certainly take a few days, which could explain the time lag between poisoning and bleeding.)

I'm not sure how likely a diagnosis serotonin syndrome is; probably less likely if he's not been taking a prescribed antidepressant or a supplement like 5-HTP - and I don't know if "SSRI-induced bleeding" would ever come into it, that'd probably be a job for a specialist (if it ever came into the picture; I was talking to a psychiatrist the other day and he'd never heard of it).

They WOULD probably quickly check things like liver function, clotting factors, INR (maybe suspecting warfarin or something, after the spontaneous bleeding?), maybe give vitamin K (used for warfarin overdoses) or protamine (heparin antagonist). I imagine a normal liver but strange clotting process would help play into the mysteriousness of the toxin.

Thanks very much for your professional opinion. Since the cause is actually poisoning, it makes sense to concentrate on chemical causes. Having discovered that poisoned mushrooms whack your liver, it seems that would be a more likely course of investigation. Plus it would presumably means lots of analyses rather than sticking him in an MRI machine or opening him up and poking about, which suits the story.

However, the bit about SSRIs is brilliant! In fact, one of the things I'd already included (for unrelated story reasons) in the differential was the possible repeated use of anti-depressants. My research so far had focussed on the coma and I didn't look into whether anti-depressants had nasty side-effects that might steer them in the wrong direction (or the right direction for the wrong reason). Given the TV-doctor-show context of the story, I think it's safe to say that the medical team are practically omniscient when the end of the episode draws near :), so they would know about SSRI side-effects, especially since they already suspect the patient of taking an overdose.

So lots to work on, along with your helpful list of stuff they would check!

Post-traumatic intracranial haemorrhage resulting in coma would be easily and quickly found, as it's common practice to do a shitload of imaging after trauma. Particularly if he does fall into a coma, he'd get an MRI or CT of the brain straight away and that'd pick up the bleed.

Isolated nose/ear bleeds prooooobably won't send you anaemic in and of themselves, unless you're seriously ill and frail, but it would be a pretty alarming klaxon for coagulopathy if the bleeding was florid. If you say fall-->coma-->bleed, I would guess that the fall caused the coma and that the bleed is not directly related to the trauma, and consequently wonder if something is impairing his coagulation. You'd test a) to confirm that and b) once confirmed, for the cause. Confirming tests are APTT and INR and fibrinogen and possibly platelets. Tests for the cause...well, there are a lot. What keaalu said about liver function and coag factor assays would go here, they would probably do a blood film and possibly mixing studies, they might look for infection with blood cultures if he's febrile. After that the tests get awfully specific, so it'd depend on what they were suspecting. If leukaemia or a problem with production, bone marrow aspirate; if poor nutrition, B12/folate levels; if lupus, antinuclear antibody tests, blah blah blah blah the list goes on.

Acquired thrombocytopenia is definitely possible. You could have the poison cause thrombocytopenia in and of itself, or have it cause an immune thrombocytopenia. The last would take a couple of days to hit, but the other two could happen instantly, just about. Or he could just get DIC from it, or from an infection, or something. I do like keaalu's suggestion of poison causing liver failure and subsequently encephalopathy and coagulopathy.

Finally, have an article on snake venom haemorrhage, it just looks interesting. :D

Edited at 2012-05-03 12:42 pm (UTC)

Thank you very much, these are excellent suggestions. I had a feeling that the first thing they would do when they got hold of him once he was unconscious would be to have a look at his head, so anything there would be identified quite rapidly. I like the idea of liver failure best because it's pretty nasty but possibly curable, and also seems to have a variety of possible causes.

I assume that if they run some standard tests on admission, they would already have eliminated some things like hepatitis, some common toxins, and they might have already checked the INR, platelet count and general liver function thingies (ALT and AST?). So it might have to be a situation where those changed as the poison affected his liver after a few days.

One thing, though, assuming his failing liver is the cause of the coma - would there be any specific way to get him out of the coma? Or if I want the patient awake, would I be better off making the coma a side-effect of the initial fall, rather than a result of the liver failure - ie, he recovers from his concussion or whatever caused the unconsciousness, only to find that the poison is really starting to kick in and cause other problems.

I have to admit my own brain is starting to hurt too, LOL. :)

Liver failure leading to hepatic encephalopathy can certainly cause coma. In addition to checking "liver function tests" - AST, ALT - check an ammonia level. It can go very high. Liver failure also can cause bleeding, as others have posted. So if your poison slowly takes out the liver, you could plausibly have the symptom progression you describe.

What is less plausible is that competent modern health care workers wouldn't think to check the liver in the case of unexplained coma. Especially because the only way to "revive" someone in hepatic encephalopathy is to give them specific medications such as lactulose, which they wouldn't think of without having done the liver test. A bare minimum of tests for a patient in coma would be a head CT, complete blood count, complete chemistry panel, blood gases, liver function inlcuding PT and PTT for bleeding problems, blood alcohol level and drug test. A spinal tap and EEG might also be on the list, and I agree with the other posters who have suggested an acetominophen level.

Yes, upon reflection, I think for the reason you've given - the doctors would have noticed it was liver failure while he was unconscious - it might be best if the coma was indeed due to a bump on the head or was a direct effect of the poison, with the liver failure being another effect that manifests afterwards. I wish I'd known about this comm before creating my symptoms or they might have been more coherent! But I suppose I'll have to blame the magic poison. At least I have a nice battery of tests for the doctors to discuss in passing. ;)


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