Wednesday, November 9, 2011

Guest Post - Chew on This

Last week we posted about the end of the Digitek MDL, and with it one of the most utterly meritless mass torts that we'd ever seen.  We mentioned, very much in passing, that the court's opinion also contained some interesting Daubert questions, without going into any detail.  We were busy, true, but frankly we also weren't familiar with the science underlying that part of the opinion.

Anyway, we got called out for that omission by Dick Dean and Matt Moriarty of Tucker Ellis & West, who have been co-lead counsel for the principal Digitek defendants.  So we called them out right back.  Since they obviously knew the Daubert aspects (and everything else) of the Digitek litigation better than we did, we invited them to prepare a guest post on the subject.

Well, they accepted, and here it is - what's behind the favorable Daubert rulings that closed out Digitek, and why they're important.  As with every guest post, the guest authors get all the credit and all the blame....


In the original blog posting about the Digitek® decision issued on November 3rd, Bexis correctly notes that the Digitek MDL was singularly meritless.  Indeed, plaintiffs’ cases were all sizzle and no steak.  But the order that put them down has a lot of meat on its bones.  In both of the two remaining cases in that MDL, the Court excluded expert testimony, digging into differential diagnosis under Daubert.  The Court focused on the experts’ reliance on “questionable scientific principles,” “unsubstantiated analogies,” and “overreaching or speculative methodologies.”  What makes the opinion so delicious is that the Court offered a rare decision about the reliability of post-mortem blood levels, in one case, and, in the other case, excluded a very well-qualified cardiologist from offering an expert opinion about his own patient.

McCornack was a wrongful death case claiming death due to digoxin toxicity.  The decedent’s blood sample was not taken until 79 hours after death.  It revealed a blood digoxin level – 3.6 ng/ml – above the upper end of the normal therapeutic range of 0.8 – 2.0 ng/ml.  But there is a phenomenon with some drugs – not all – called postmortem redistribution ("PMR").  Some drugs are stored in tissue to work properly.  At the time of death, postmortem redistribution begins, and they are released from the tissue and returned to the blood stream.  This results in a higher level of drug in the blood after death than was present during life.  This is an interesting subset of toxicology.

Plaintiffs had two experts who opined that the decedent, while living, had an elevated digoxin level.  They based their opinions on the 3.6 ng/ml postmortem level.  In their brief, the Digitek defendants challenged not only their ability to express those opinions, but also the admissibility of the underlying test result itself.   Defendants argued that there was no reliable basis on which to conclude what the decedent’s level of digoxin was just before he died.

While there has been significant comment in the toxicology literature about problems with interpreting the meaning of postmortem blood results with some drugs (see Defendants’ brief), there is relatively little case law on this issue. See, e.g., Bourne, v. E.I. DuPont de Nemours & Co., 189 F. Supp.2d 482, 499 (S.D.W. Va. 2002); Battle v. Gold Kist, Inc., 2008 WL 4097717, at *3 (M.D. Fla. Sept. 2, 2008).

It is generally recognized by reputable toxicologists that one cannot calculate back from a postmortem level to determine the level before the time of death with any degree of reliability.  A multiplicity of factors can compromise the value of a blood result when postmortem redistribution is at play.  These particular Plaintiffs’ experts had no reliable way of determining the decedent’s digoxin level at the time he died, and they were barred as a result.  In a nutshell, Judge Goodwin found – “It is Plaintiffs who must produce evidence to support the admissibility of that finding and the opinions related to it. They have produced a pittance. The key problem with the opinions of Dr. Mason and Mr. Gibson is that they did not adequately account for the PMR effect.” Page 28 of Opinion. He quoted the two experts:

Mason: “It would be some esoteric fudge factor for me to say how much was redistributed. I don’t know.”

Gibson: “I mean, I think Dig levels with postmortem redistribution do tell you stuff, but I don’t think you can extrapolate backwards on one data point.”

The Court viewed this as a classic case of ipse dixit.  In addition to barring their testimony, the Court excluded the blood result itself.  It should be noted that Plaintiffs had a third expert who conceded that it was “more likely than not” that the decedent’s pre-death blood digoxin concentration was “substantially lower” than the 3.6 ng/ml level.  That same expert would not have concluded that Mr. McCornack died of digoxin toxicity.  The decision is a significant step forward in a very narrow area of toxicology.

In the Vega action, the Plaintiff offered Dr. Reynolds Delgado to opine on defect and causation.  Dr. Delgado is “a world-renowned, board-certified cardiologist that practices in one of the world’s best heart institutes,” and who had treated the decedent for the last six years of her life. But his litigation opinion, implicating digoxin toxicity from defective Digitek® as a causal factor in the decedent’s death, was at odds with the contemporaneous medical records and his own treatment of the decedent.

The defendants challenged Dr. Delgado on several grounds.  First, he had no qualifications to opine on product defect; second, he concluded that there was a defect without using any methodology (insufficient facts and data); and third, he had no basis for concluding that digoxin toxicity caused the decedent to die.

Judge Goodwin went for the third challenge on Dr. Delgado’s causation opinion – the “lack of a proper differential diagnosis is decisive.”  The Court emphasized that the decedent “was in terrible health,” noting that “just a sampling” of her “serious issues” included: obesity and hypertension, “congestive heart failure spanning over a decade,” and a heart transplant, to name a few.  Given this history, it was fatal that Dr. Delgado did not “adequately account for the many other conditions that might have caused [the decedent’s] decline and death.”

Further, the Court rejected Dr. Delgado’s reliance on a study of outcomes associated with blood digoxin levels.  The Court observed that the decedent’s “progressive heart failure was more severe than the study participants” and that the study did not show a statistically significant increase in digoxin-related death at the blood digoxin level at issue in this case.  The Court regarded this as a failed analogy.

The Court could have excluded the McCornack and Vega experts on qualifications grounds alone and disposed of the cases without digesting the central scientific issues.  But the Court ate these experts for lunch, ultimately finding that their approaches were “inconsistent with good science.”  Kudos to Judge Goodwin.