Immediate Death upon Losing Liver?

[mumblemumble]

Yeah, maybe a few hours...reason why I say hours, is really, battles take hours, but irl take a few minutes, maybe. The time difference, and time needed to react should be adjusted accordingly, a few hours would put you on an EXTREMELY tight schedule, like, perhaps IMMEDIATELY needing medical care, and needing a new liver in a few more hours time. Essentially do or die, no time for traders, no time for anything else, but enough to stabilize, slaughter a prisoner for one, and save them.

[Mutineer]

I have to point out that if liver is destroyed by shot try you are dead. I do not know medical procedure that restore the liver or even keep person alive why doing that. Liver perform extremely important function and we do not have back up liver.

Even any damage to liver because of amount of blood going try it and critical function it has will couse near instant death. Think about liver as a brain of chemistry of our body.

[brcruchairman]

I have to point out that if liver is destroyed by shot try you are dead. I do not know medical procedure that restore the liver or even keep person alive why doing that. Liver perform extremely important function and we do not have back up liver.

Even any damage to liver because of amount of blood going try it and critical function it has will couse near instant death. Think about liver as a brain of chemistry of our body.

This appears to be untrue; the liver is one of the most commonly injured organs in abdominal trauma¹, and many procedures exist for repair of the liver in patients who, in simple terms, are no longer bleeding to death.²

Death, in most medical terms, is the cessation of brain, cardiac, or respiratory function.³ The chief mechanisms for death in the case of abdominal (and, consequently, not thorasic) trauma are blood loss and infection.⁴ Infection, we can reasonably assume, is a medium-to-long-term concern, something that would occur well after the conclusion of a gunfight. Blood loss is the mechanism which, I believe, people here are advocating. Neither of these come close to "instant death". Even death from volume shock, in the event of blood loss, takes time. (Previously cited was the 30 seconds it takes from a severed femoral artery; most injuries take significantly longer due to smaller blood vessels and thus lower flow rates.)

The argument has been well-made by Wex that the liver contains significant arteries; this is correct. However, the amount of blood flowing through the liver isn't quite at "instakill" levels; the haepatic artery, for instance, has been estimated to have 800 to 1200 ml/min flow. The human body has around 5 L of blood in it.⁵ For an adult, 2000 ml (2 L ) of blood loss is required for Class III Hemorrhagic Shock.⁶ Assuming that the liver is destroyed in such a way that there are both no blockages to stem the flow, and that the arteries do not constrict in response to trauma (an unlikely but not impossible scenario) we'd be looking at, at worst, a bit under two minutes for death by blood loss. This would likely be longer; Class IV Hemorrhagic Shock exists, and many wounds have obstructions whether artificial (foreign objects, pulped flesh) or natural (clotting) which further slow the rate of blood loss.

In light of the above, it does not, to me, seem out of the question to make the mechanism for death for noncardiac and nonneurological injuries be blood loss or infection. In addition to being more realistic, this would also add the interesting incentive to, even in good colonies, harvest organs from prisoners, specifically to plop back into your colonists; it's very true that nobody can live without a liver for long, but it seems reasonable that with sufficient facilities (medical bed, vitals monitor in sterile room) and a highly skilled doctor (planetary masters should at least be skilled enough) to remove dead tissue and transplant a working liver into a patient within hours. From from an assured success, of course, but within the realm of possibility. I believe others in this thread (e.g., mumblemumble ) have already said much of this, but I figured I'd add my two cents.

Also, if I misinterpreted any of my sources, messed up any of my numbers, or made a straight up unsubstantiated claim, please let me know; you don't use science to prove you're right, you use it to BECOME right, so if my argument is wrong, I'd like to know so I can switch sides. :p

¹: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3097559/
²: ibid
³: http://www.medicinenet.com/script/main/art.asp?articlekey=33438
⁴: https://en.wikipedia.org/wiki/Abdominal_trauma
⁵: http://hypertextbook.com/facts/1998/LanNaLee.shtml
⁶: http://www.fpnotebook.com/er/exam/HmrhgClsfctn.htm

[Wex]

The haepatic artery has about 25% of the liver blood supply, the portal sistem (veins) bring the liver the remaining 75%.
You will die much faster than you tought.
https://en.wikipedia.org/wiki/Portal_vein

[SpaceDorf]

I am always amazed how awesome the human body is, everytime I learn something new.

[brcruchairman]

The haepatic artery has about 25% of the liver blood supply, the portal sistem (veins) bring the liver the remaining 75%.
You will die much faster than you tought.
https://en.wikipedia.org/wiki/Portal_vein

Aaah, thank you! I was working under the assumption that the portal veins were actual veins; I was looking only at blood entering the liver. However, as you've pointed out, the Portal vein is actually an artery (whee, oxymoronical nomaclature!)

It is worth noting, however, that the actual  blood flow rate is less than your source claimed; the figure I found claims ~850 ml/min max¹ (which was in the supine position; that value is further lowered when standing) which appears to be less than the haepatic artery. This still leaves more than 60 seconds under optimal injury conditions (id est, no clotting, no obstructions, total failure of natural arterial trauma response) which is unlikely in a battlefield setting. So while you're correct that a patient would die faster than I thought, I would humbly submit that they may die slower than you had thought. It seems that we're both learning today.

I'd like to take a moment to look at wound responses to trauma. In particular, arteries have been known in the case of clean cuts to constrict, reducing blood loss.² However, the same source further notes that badly lacerated arteries (which would be more common in shrapnel wounds) cannot constrict, and may in fact bleed more. Further, the assumption of no blood clotting is also not as unreasonable as I had first thought; 1 in 4 patients with severe trauma (of which getting shot in the liver certainly qualifies) experience coagulopathy³ (inability to clot). While this does mean that the majority of patients will live much longer than I predicted, it also implies that 25% of livershot pawns should live only around my minimum estimate of 60 seconds.

In conclusion, even a shot that (magically) destroys the entire liver, leaves no debris, and shreds the arteries to prevent constriction can be expected to cause death in the worst case within 60 seconds. As the translation between human time and rimworld time has not been established (e.g., would that be 1/60th of a game hour? 60 real world seconds?) a worst-case liver shot being instant death remains up for debate. In more typical cases, one can expect longer pawn survival, though the precise duration remains, as before, unclear.

Thank you, Wex, for correcting my misconception regarding the portal veins; your point is well taken, and in my quest to find more sources, I found that my own position was nowhere near so ironclad as I thought. Thank you! I appreciate having a good partner to debate with, especially one who's kind enough to provide his sources. *hugs!*

I am always amazed how awesome the human body is, everytime I learn something new.

I know, right?! That's part of why I love participating in debates like this; I learned today that, in cases of hemorrhagic shock, the cause of death actually isn't directly from oxygen deprivation, but rather from the resulting lactic acid; see, without enough oxygen (a state caused by shock) the cells start anaerobic metabolism, the byproduct of which is (among other things) lactic acid. It's that acid which causes the cell death! Our bodies are so adaptable that they keep trying, right to the end, to live! I also puts exercise into a new light; that burn you feel is partially lactic acid, so in a way when you exercise you can feel like you're fighting death! "Ha HA! I simulate death in my muscles just to feel ALIVE!" We're all badasses, every last one of us. ^ ^

¹: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1434022/
²: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3860641/
³: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4608348/ (Introduction)

[jeffus]

The haepatic artery has about 25% of the liver blood supply, the portal sistem (veins) bring the liver the remaining 75%.
You will die much faster than you tought.
https://en.wikipedia.org/wiki/Portal_vein

Aaah, thank you! I was working under the assumption that the portal veins were actual veins; I was looking only at blood entering the liver. However, as you've pointed out, the Portal vein is actually an artery (whee, oxymoronical nomaclature!)

It is worth noting, however, that the actual  blood flow rate is less than your source claimed; the figure I found claims ~850 ml/min max¹ (which was in the supine position; that value is further lowered when standing) which appears to be less than the haepatic artery. This still leaves more than 60 seconds under optimal injury conditions (id est, no clotting, no obstructions, total failure of natural arterial trauma response) which is unlikely in a battlefield setting. So while you're correct that a patient would die faster than I thought, I would humbly submit that they may die slower than you had thought. It seems that we're both learning today.

I'd like to take a moment to look at wound responses to trauma. In particular, arteries have been known in the case of clean cuts to constrict, reducing blood loss.² However, the same source further notes that badly lacerated arteries (which would be more common in shrapnel wounds) cannot constrict, and may in fact bleed more. Further, the assumption of no blood clotting is also not as unreasonable as I had first thought; 1 in 4 patients with severe trauma (of which getting shot in the liver certainly qualifies) experience coagulopathy³ (inability to clot). While this does mean that the majority of patients will live much longer than I predicted, it also implies that 25% of livershot pawns should live only around my minimum estimate of 60 seconds.

In conclusion, even a shot that (magically) destroys the entire liver, leaves no debris, and shreds the arteries to prevent constriction can be expected to cause death in the worst case within 60 seconds. As the translation between human time and rimworld time has not been established (e.g., would that be 1/60th of a game hour? 60 real world seconds?) a worst-case liver shot being instant death remains up for debate. In more typical cases, one can expect longer pawn survival, though the precise duration remains, as before, unclear.

Thank you, Wex, for correcting my misconception regarding the portal veins; your point is well taken, and in my quest to find more sources, I found that my own position was nowhere near so ironclad as I thought. Thank you! I appreciate having a good partner to debate with, especially one who's kind enough to provide his sources. *hugs!*

I am always amazed how awesome the human body is, everytime I learn something new.

I know, right?! That's part of why I love participating in debates like this; I learned today that, in cases of hemorrhagic shock, the cause of death actually isn't directly from oxygen deprivation, but rather from the resulting lactic acid; see, without enough oxygen (a state caused by shock) the cells start anaerobic metabolism, the byproduct of which is (among other things) lactic acid. It's that acid which causes the cell death! Our bodies are so adaptable that they keep trying, right to the end, to live! I also puts exercise into a new light; that burn you feel is partially lactic acid, so in a way when you exercise you can feel like you're fighting death! "Ha HA! I simulate death in my muscles just to feel ALIVE!" We're all badasses, every last one of us. ^ ^

¹: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1434022/
²: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3860641/
³: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4608348/ (Introduction)

Learning more from this thread than i did in biology lol 

Though isnt it strange how resilient yet at the same time fragile the body is.People survive steel bars going through their head, yet people can die from infection that sets in from a splinter of wood. Or the same person that survives the steel bar could die from falling and smacking their head on the ground just a tad bit too hard

Its very interesting