Minnesota State Court Judge Rules Against Bair Hugger Plaintiffs

“State Court Claims in Bair Hugger Warming System Dismissed”

By Staff (February 16, 2018)





(MASS TORT NEXUS MEDIA) Defense won a major legal victory in a Ramsey County, MN court this week in the state court litigation where orthopedic surgery patients alleged the 3M company’s Bair Hugger forced-air warming systems caused their deep joint surgical infections.

Ramsey County District Judge William H. Leary’s ruling on January 9, 2018 dismissed all of the lawsuits filed by Minnesota residents against 3M Company, maker of the Bair Hugger system. The opinion stated that the plaintiffs had presented no evidence showing that their theory of the case, that the Bair Hugger system may increase the risk of surgical infection, by offering any supporting evidence that’s accepted in the scientific community.

There is no generally accepted scientific evidence — and plaintiffs offer none — that the risk of infection associated with FAWs [forced-air warming systems] is greater than that associated with patients who are not warmed during surgery,” Leary wrote Monday, granting 3M’s motion for summary judgment. There was also no generally accepted evidence that other companies’ warming devices had lower rates of infection than 3M’s, the judge wrote.

Defense counsel is pleased with the ruling, but counsel for plaintiffs said the cases are not resolved yet, stating “Plaintiffs are surprised and disappointed with the Ramsey County Order, and will appeal,” according to plaintiffs’ attorney Genevieve Zimmerman.


U.S. District Judge Joan Ericksen ruled in December that plaintiffs can present their expert witness to jurors to support their claims, just as 3M can present their own experts to rebut the allegations.  Leary’s ruling on the state-court cases doesn’t directly impact the much larger federal litigation, known as MDL 2666,3M BAIR HUGGER MDL 2666 Briefcase, where more than 4,000 lawsuits filed by patients from across the country have made the same allegations as the Ramsey County plaintiffs, using many of the same expert witnesses and published studies that Judge Leary ruled were not science based.

The first “bellwether” trial in MDL 2666, in Gareis vs. 3M, is slated to begin in April 2018, Mr. Gareis is a South Carolina resident who claims the Bair Hugger device caused an infection during a 2010 hip replacement surgery.

The Food and Drug Administration says that using systems like the Bair Hugger to keep patients’ bodies warm before and during surgery can result in less bleeding, faster recovery times and a lower risk of infection. 3M said its Bair Hugger system, which was originally designed by Minnesota’s Dr. Scott Augustine, has been safely used in more than 200 million surgeries over three decades.

Dr. Augustine himself now says that the forced-air system he invented has flaws that increase the risk for infection. Leary’s ruling noted that Augustine formed a new company that sells a competing patient-warming device.

In an e-mail, Augustine said he was “very sad” for the Minnesotans who contracted infections but then had their cases dismissed by Leary’s ruling. “Judge Leary’s opinion ignored the excellent science supporting the plaintiffs’ claims,” stated the device inventor.

The design flaw in the Bair Hugger, according to the MDL and state court plaintiffs, is that the device creates warm air currents that rise from the floor of the operating room with enough lift to pick up germ-containing particles and deposit them in a surgical wound. The plaintiffs have also asserted that device itself including the air-blower may harbor and breed the bacteria, which is then speared throughout the operating room.

Plaintiffs have not yet offered direct evidence that shows that a germ-laden particle traveling from the floor of an operating room and into a surgical wound via air currents created by the Bair Hugger is a viable method of contamination or transfer of infectious particles. However, they do have computer modeling showing that it is possible, a significant group of experts who say it’s likely to happen, and published studies that they say support their allegations. 3M attempted to have the experts barred in the federal MDL 2666, who assert the Bair Hugger device cause post- surgical infections in court filings during the fall of 2017, and which Judge Joan Ericksen ruled against in a December 13, 2017 Order, stating “the issue of believing the experts is up to the jury” and denied defense attempts to exclude plaintiff experts.

3M asserts the science behind the safety of its air warming system is sound and is supported by numerous experts and studies. In the motion for summary judgment in Ramsey County, company lawyers said plaintiffs presented no evidence of any doctor reporting a Bair Hugger system causing a surgical infection.


The state and federal judges were sitting side by side in court during a three-day hearing last October about expert testimony, yet they reached different conclusions about whether to allow the plaintiffs’ experts to testify. However, the judges were applying different legal standards in their analyses.

The federal rules say the judge need only exclude testimony that is so fundamentally unsupported that it cannot offer assistance to the jury, see MDL Order Denying 3M Motion to Exclude Plaintff Experts.

In Minnesota state courts, the bar for experts is higher , litigants are required to show that evidence supporting expert testimony is generally accepted within the relevant scientific community if the expert is presenting a “novel” theory, such as the Bair Hugger increasing infection risks.

3M was contacted to provide comments on the state court ruling and how it affects their strategy in both state and federal court, but did not respond.

Share this Post: