K_Z
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I know this isn't really on-topic, but since the situation with the pregnant woman was brought up, I have been wondering something. Was the fetus also brain dead? I think the reporting on that case was very sloppy because the science/medicine wasn't understood by the journalists, and my guess is the doctors thought it was likely but were not sure.
I see so many articles saying the mother was without oxygen for an hour, likely due to a blood clot. If the bloodclot blocked bloodflow to her brain, she could be deprived of oxygen, but the fetus would not be if she was still breathing, right, and the blood was flowing through the umbilical cord? But if it was for an hour, it still seems long enough that the fetus also would have been deprived of oxygen too long. Not sure if it works differently given how a fetus receives oxygen.
Then articles report that the fetus wasn't developing correctly, possibly due to the oxygen deprivation. But is fetal development driven by the brain? It seems the fetus would develop mostly normal physically, but have no chance at survival. The deformities could have been preexisting, but it's just a weird situation and I was wondering how that would work. It seems like maybe no one knew exactly what would result. But it would seem that the fetus was also legally dead, and yet that never really gets mentioned.
I'll just chime in with a brief comment here (lol, am I ever brief?!), since this is off topic. Uteroplacental perfusion pressure is highly dependent on the mother's systolic blood pressure (not mean arterial pressure). Add to that the fact that placental perfusion is not auto regulated, meaning the placental vessels are in a maximally dilated state normally, but ARE responsive to biochemical events and drugs, etc which cause vasoconstriction. So, what all that means is that if mother develops a severe drop in systolic blood pressure, the uteroplacental circuit is woefully underperfused. (And a maternal systolic BP at or below 100 is worrisome.) So, in the case of a trauma patient, or a mother with something like a big pulmonary embolism, who has been "down" for an unknown period of time, yes, the fetus is highly compromised during that interval, even if there is some degree of maternal circulation and respiration.
(It's actually more complex than that, but I want to keep this brief! I won't go into acid/base issues, and the oxyhemoglobin dissociation curve, and the effects of fetal hemoglobin.)
We currently don't have any medical diagnostic mechanism to test for intrauterine fetal brain death, at least not that I'm aware of. And assessing the extent of hypoxic damage in a very immature fetus (the Munoz fetus was about 13 weeks when she collapsed) is just very imprecise. Most fetal monitoring looks at patterns of heart rate, accelerations in response to stimulation, etc. which are indirect measures of placental insufficiency, placental infarcts (dead spots), etc. In a situation like the Munoz case, with arrest and maternal brain death, the fetus would be presumed by most mainstream docs as being tremendously compromised, even if the fetus still had a heartbeat when the maternal circulation was restored. That was an incredibly sad and frustrating case at every level. I hope her husband and son are rebuilding their lives as best they can.