posted by admin on Jun 5
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1 with a reasonable degree of medical probability,
2 correct?
3 A Well, you mean how long it was? No.
4 Q How many times it was low. You do not know
5 with a reasonable degree of medical probability,
6 correct?
7 A Well, I’d have to — I haven’t reviewed the
8 ultrasound itself, so I’d have to go to that to find
9 out, but –
10 Q You could do that. I’m not prohibiting you
11 from looking at anything you want now, sir.
12 A Well, I don’t think I could interpret it
13 very well.
14 Q Okay. Do you know, sir — this 68 to 87,
15 do you know when either number occurred first between
16 11:38 and 12:06?
17 A No.
18 Q Do you know, sir, if either number was
19 associated with a deceleration as opposed to a
20 bradycardic period?
21 A I’m not sure what you mean.
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1 Q You do know the difference between a
2 deceleration and bradycardia, don’t you?
3 A No. What do you mean?
4 Q A deceleration, as you’ve testified in many
5 other cases, is where the fetal heart rate goes down,
6 and then comes back up to baseline. A bradycardia, as
7 you have testified in other cases, is where the fetal
8 heart rate goes down and stays down.
9 MR. J: Objection.
10 Q Using those definitions that you’ve given
11 in prior depositions, do you know if the 68 or 87 here
12 was part of a deceleration or a bradycardia?
13 MR. K: This is Jk. Objection
14 to form.
15 MR. J: Objection also.
16 A Well, it was clearly bradycardia. You mean
17 whether it was associated with a uterine contracture –
18 contraction?
19 Q Well, decelerations are associated with
20 uterine contractions, that’s correct. If you need that
21 information, do you know whether the 68 or 87 was
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1 associated with a contraction or bradycardia?
2 A Well, I would call it bradycardia because
3 the levels were so low. I’m not sure I’d make that
4 distinction between bradycardia and deceleration.
5 Q Okay. Now that I’ve explained what a
6 deceleration is, are you familiar with the term
7 deceleration of the fetal heart rate?
8 A Yeah. Well, I guess what you’re saying, a
9 mild — a mild decrease in heart rate would be a
10 deceleration. I think if it went this low, you’d still
11 call it a bradycardia.
12 Q Okay. Do you know, after the heart rate
13 went to 68 or 87, whether or not the heart rate went
14 back to baseline?
15 MR. J: While in ultrasound, Z?
16 MR. G: Yes, sir.
17 MR. J: Okay. Thank you.
18 A No, I’m not sure.
19 Q And you also don’t know with a reasonable
20 degree of medical probability, correct?
21 A Yeah, that would be the same. I think
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1 “don’t know” you can translate as not reasonable
2 medical probability.
3 Q And, sir, assuming even hypothetically the
4 68 or 87 is part of a deceleration, you would not know
5 if it’s part of an early variable or late deceleration,
6 correct?
7 A I don’t think it — you’re making a useful
8 distinction. I think it’s bradycardia.
9 Q Do you know what obstetricians would use as
10 the definition for bradycardia?
11 A I would say below — below a heart rate of
12 a hundred.
13 Q And do you know how long the heart rate has
14 to stay below a hundred under the obstetrician’s
15 definition before it can be called a bradycardia?
16 A No, I don’t.
17 Q You mention in your report at the bottom,
18 “Although the slow heart rate and placenta previa
19 indicate that the threshold for injury had been
20 surpassed at the time of the ultrasound, I have no
21 information about how long before the ultrasound this
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1 had occurred.” Do you see that? Do you see that?
2 A Okay. Yeah. Surpassed –
3 Q You’re still reading? I’m sorry.
4 A “No information about how long before the
5 ultra-” – right. In other words, whether previous
6 episodes had also changed the cerebral blood flow.
7 Q Right. Now, when you mention that
8 sentence. “… the slow heart rate and placenta previa
9 indicate the threshold for injury had been
10 surpassed…,” what is it about the placenta previa, if
11 we dissect that out, indicates to you that a threshold
12 for injury has been surpassed?
13 A Well, I think it’s really the placenta
14 previa associated with the abruption that was noticed.
15 Q Why didn’t you mention the word “abruption”
16 in your report at all?
17 A I don’t know. It’s on the — it’s on the
18 ultrasound report. I’m not sure why I didn’t put that
19 in.
20 Q Okay. Are you saying basically when
21 there’s an abruption involved that a threshold for
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1 injury is surpassed?
2 MR. J: In and of itself we’re
3 asking?
4 Q In and of itself. Or is it really the slow
5 heart rate that tells you the threshold for injury has
6 been surpassed?
7 A Yeah, I think it’s a combination of the
8 abruption with bradycardia.
9 Q Okay. Well, I’d like to isolate out the
10 abruption. What does an abruption tell you at all
11 about a threshold for injury being surpassed?
12 A Well, the abruption tells you that there’s
13 a potential for blood loss from the fetus, and the
14 bradycardia indicates that that blood loss probably has
15 been physiologically significant for the fetus. So
16 it’s really the combination.
17 Q Now I understand. Okay. Sir, would you
18 know, is there any literature out there concerning
19 fetuses who have had bradycardias before delivery and
20 correlating that with subsequent outcome?
21 A You mean with? With abruption.
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1 Q With anything.
2 A These are in prematures and –
3 Q Well, how many weeks do you think this
4 child was, sir?
5 A I think it was between 28 and 31 weeks.
6 Q Okay. Any literature out there with
7 preemies of that same gestational age suffering a low
8 heart rate, any literature out there with subsequent
9 neurological outcome?
10 A Well, I think I’d go back and explore this
11 Volpe literature indicating that fluctuations in
12 cerebral blood flow are linked to intraventricular
13 hemorrhage. And I think that there’s, you know, a
14 series of articles that his groups worked on looking at
15 the relationships between fluctuations in blood flow
16 and hemorrhage. But that’s the — you know, I think
17 the accepted mechanism of hemorrhages, fluctuations in
18 cerebral flood flow. And bradycardia is a prominent
19 cause from that. And in a premature infant like this,
20 we can assume that the cerebral circulation is pressure
21 passive. So any bradycardia in the premature infants
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1 is going to be translated into reduced blood flow in
2 the infant.
3 Q Do you know of any of that Volpe literature
4 that talks about bradycardia for even a few seconds
5 causing brain damage in a subsequent infant?
6 A In a what?
7 Q Subsequently for that infant.
8 A Yeah, I think there’s — I think if you
9 follow the Volpe literature, there’s certainly
10 correlations between oscillations and cerebral flood
11 flow and bradycardia in the newborn nursery linked to
12 periventricular leukomalacia.
13 Q And in all of those articles by Volpe, and
14 even in his textbooks, isn’t it fair to say that
15 bradycardia has to last for a certain amount of time
16 before it will affect the fetus?
17 A I’m not sure of that. The main issue is
18 that the — it’s related to oscillations of blood flow,
19 ups and downs in blood flow. I don’t think there’s a
20 good connection between exactly how much time the
21 bradycardia occurs.
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1 Q Okay. In all of Volpe’s literature where
2 he talks about the oscillations, wouldn’t you agree
3 that those infants who are brain damaged have multiple
4 oscillations of bradycardias and normal heart rates?
5 A Well, at least they — I’m not sure if they
6 all have multiple. They have — I’m not sure there’s a
7 good connection between exactly how many and how long
8 they last, but there is a strong link between
9 bradycardia and — and oscillations in cerebral blood
10 flow.
11 Q Do you know of a single article, sir,
12 whether it’s by Volpe or anybody else, that says just
13 one or two oscillations of heart rate to a premature
14 fetus is enough to cause neurological brain damage to
15 the extent that this fetus has?
16 A I don’t — I can’t really think of
17 literature that’s addressed that one way or the other.
18 Q You mention in your report in the middle of
19 the paragraph, “My general opinion is based on research
20 indicating that injury to the developing brain occurs
21 when a critical threshold is reached as opposed to
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1 occurring incrementally in the cumulative dose-related
2 fashion.” Do you see that sentence?
3 A Yeah.
4 Q Are you referring to your own research,
5 sir?
6 A No. Well, I think my research, but other
7 research indicates that the — for example, the
8 G-F research, you withdraw blood, you
9 reinsert blood, and once you — once you’ve reached a
10 threshold of reduced blood flow, then that’s enough to
11 damage the brain.
12 Q Would your own research be included in
13 those articles you identified at the beginning of the
14 deposition from your CV?
15 A No. I just actually cited review articles
16 which are more clinical in nature. Mine is — related
17 to this topic is — is more related to — I guess I
18 don’t have anything definitely related to clinical work
19 on this topic, so I cited reviews that I wrote.
20 Q Then why did you tell me your opinion’s
21 based on your own research and others’ research,