8th Circuit reinstates plaintiffs’ experts, revives 3M Bair Hugger litigation

August 16, 2021. In Amador v. 3M Co. (In re Bair Hugger Forced Air Warming Devices Prods. Liab. Litig.), __ F.4th __, 2021 U.S. App. LEXIS 24255 (8th Cir. 2021), the Eighth Circuit Court of Appeals reversed summary judgment in favor of defendant 3M, reviving plaintiffs’ negligence and strict liability claims in a Multidistrict Litigation (MDL) involving nearly 6,000 lawsuits. Plaintiffs allege that they suffered periprosthetic joint infections (PJIs) due to the use of 3M’s Bair Hugger device during orthopedic-implant surgeries. The Bair Hugger is “a forced-air device used to keep patients warm during surgery so as to stave off hypothermia-related complications that can arise during or after surgery.” Plaintiffs allege that the forced-air warming device introduced microbes into the surgical site during surgery, either by creating “currents that carry ambient bacteria from nonsterile areas of the operating room to the surgical site” or by blowing bacteria present inside the device out into the operating room, and thereby caused the PJIs.

After the first bellwether trial, which resulted in a jury verdict for 3M, the MDL court excluded plaintiffs’ engineering and general-causation medical experts and granted summary judgment to 3M, dismissing all MDL claims. On appeal, the Eighth Circuit applied the standard for the reliability inquiry of the Daubert test, concluding that the MDL court erred in excluding plaintiffs’ engineering expert when the physics underlying his model are reliable. The court further found that the fact that the model was developed for litigation goes to weight rather than admissibility. Regarding plaintiffs’ general-causation medical experts, the 8th Circuit determined that the experts’ causation theories were not so fundamentally unsupported that they should be excluded. Any weaknesses in the experts’ theories may be tested by cross-examination and admission of contrary evidence. With plaintiffs’ expert reinstated, the Eighth Circuit reversed the MDL court’s grant of summary judgment.

To read more about the Amador opinion, click here.

To read the Amador opinion, click here.