Lawsuit Information Center
The Bair Hugger is a medical device that is used to keep patients warm and regulate body temperature during surgery. New research has shown, however, that the Bair Hugger increases the risk of infections by pushing bacteria into the body during surgery. This has prompted thousands of Bair Hugger infection lawsuits, which have been consolidated into a class action MDL.
Bair Hugger Lawsuit Update
May 1, 2025: The Bair Hugger MDL in the District of Minnesota, presided over by Judge Joan N. Ericksen, has 8,292 active cases as of May 1, 2025, with a total of 9,535 historically filed.
April 20, 2025: A status conference is scheduled for May 27, 2025, before Magistrate Judge David T. Schultz. This conference is expected to address the progression of bellwether trials and other pretrial matters.
March 3, 2025: M3M filed today a motion to dismiss 103 lawsuits, asserting that these plaintiffs failed to provide adequate documentation confirming the use of a Bair Hugger device during their surgeries. Even if this motion is granted, over 7,800 lawsuits would remain active.
March 1, 2025: Judge Ericksen has ruled that plaintiffs’ expert witnesses on general causation could present their testimony to juries. This decision is a big deal because it allows plaintiffs to argue that the Bair Hugger device can cause infections.
July 1, 2024: There was a decent-sized increase in the number of plaintiffs in the Bair Hugger Forced Air Warming Devices Products Liability Litigation MDL. The number of filed lawsuits went up from 6,858 on June 1 to 7,187 in July 1, reflecting ongoing filings.
June 18, 2024: A Missouri appeals court upheld a defense verdict in a case where a woman alleged that 3M Co.’s Bair Hugger patient warming system was defectively designed and caused her postoperative infection. The court affirmed that the trial court did not err in its evidentiary rulings or abuse its discretion in limiting expert testimony.
The plaintiff had undergone knee surgery in November 2016, subsequently developed an infection, and underwent a second surgery in January 2017. She sued 3M for negligent and defective design, manufacturing, and marketing, claiming the device contaminated the air and caused her infection. A jury found in favor of 3M, and her motion for a new trial was denied.
Plaintiff appealed, arguing that the trial court improperly limited her cross-examination of 3M’s expert witnesses. She argued that this limitation prevented her from challenging the credibility of these experts. The appeals court shot down that argument, finding that her lawyers did not make necessary offers of proof to support her claims.
Additionally, the plaintiff contended that the trial court erred in allowing remote testimony from an expert due to their limited availability. Arguments like that are surefire losers.
May 1, 2024: The parties involved in the Bair Hugger multidistrict litigation are scheduled to bring six selected cases to trial in March 2025, according to a scheduling order by U.S. Magistrate Judge David T. Schultz.
Over the past year, the parties have been engaged in settlement discussions with the help of Special Master and retired judge James M. Rosenbaum. But there is no Bair Hugger settlement. So additional trials may be necessary to aid in the settlement process. Consequently, six cases have been jointly selected for trial to ensure a prompt and efficient resolution.
The scheduling order outlines that all fact discovery must be completed by September 3, 2024. Plaintiffs are required to disclose their expert witnesses by September 3, with the defense’s disclosures due by October 1. Depositions must be completed by November 1, and all dispositive motions filed by November 29. Additionally, a status conference with Judge Joan N. Ericksen is set for March 19, 2025.
April 17, 2024: Judge Ericksen remanded 28 cases to the districts where they would have originally been filed.
February 6, 2024: The MDL judge granted a motion to remand a case to a Texas court after determining that 3M Co. failed to prove that certain defendants were fraudulently joined. This decision moves the case back to the Harris County, Texas, District Court.
The case involves allegations that the Bair Hugger patient warming system caused a postoperative infection. 3M had initially removed the case to federal court and sought to stay proceedings pending its transfer to the MDL. However, the court found that 3M did not demonstrate that the plaintiff lacked a viable cause of action against the nondiverse defendants and thus granted the remand.
October 28, 2023: As we talked about in the July 14th update, the plaintiffs attempted to have Judge Ericksen recused, claiming bias due to the judge’s newly hired law clerk, a retired defense lawyer. The plaintiffs argued that the law clerk’s background and the judge’s rulings showed partiality.
The appellate court rejected the recusal effort. The court clarified that hiring decisions and the identities of law clerks do not require disclosure to the parties. The judge emphasized that the law clerk had no conflicts of interest and maintained confidentiality as required.
The plaintiffs also complained about the judge’s past rulings, but the court noted that dissatisfaction with judicial decisions does not justify claims of bias.
July 27, 2023: The latest update on the 3m Bair Hugger cases found 5,251 pending claims in the MDL. This quiet MDL is the 8th largest in the country.
We have opened up the comments section below if you want to share your experiences.
July 14, 2023: While 3M is unhappy with every judge within ten feet of the 3M earplug lawsuits, it has a different take on the Bair Hugger lawsuits. The plaintiffs’ lawyers have raised objections about a potential conflict of interest, as the magistrate judge had previously owned 3M shares and his wife had an association with the company. 3M wants to keep the judge in place.
The Bair Hugger plaintiffs’ lawyers have also tried to disqualify the main MDL judge, too. Why? The reasons for this remain confidential. But confidential or not, that motion was rejected as this new one will likely be as well. The reality is that it is not comforting to return to the same judge who tried to dismiss your cases and was overturned on appeal.
June 1, 2023: The Supreme Court has rejected 3M’s petition for review concerning the re-establishment of consolidated litigation over its Bair Hugger surgical warming blankets. 3M had argued that the Eighth Circuit had employed an excessively lenient standard in allowing expert witnesses for patients who underwent joint-replacement procedures. But the Supreme Court has no interest in even hearing the case.
Despite the court’s decision, there is honestly not abundant enthusiasm regarding these lawsuits. Nonetheless, the possibility of settlement remains. Not long ago, the presiding judge in the MDL appointed retired Magistrate Judge Arthur Boylan as a mediator. Renowned for his ability to navigate complex legal disputes through mediation, Boylan’s involvement offers a glimmer of hope. His role is to guide negotiations and dialogue among the parties, aiming to find a solution that everyone finds acceptable.
April 17, 2023: As of today, the latest update is there are 5,173 plaintiffs are in this warming blanket class action lawsuit.
April 17, 2023 Update: Plaintiffs in a case against 3M have filed a disqualification motion against US District Judge Joan Ericksen of Minneapolis and Judge David Schultz, the federal magistrate in the multidistrict litigation (MDL). The motion alleges that Ericksen engaged a retired products liability defense attorney as an adviser while considering a critical 3M motion and relied on his legal theories in her decision, which was later overturned by the 8th US Circuit Court of Appeals. The plaintiffs also claim that Schultz’s financial adviser bought and sold 3M shares during the MDL. 3M opposes the disqualification of Ericksen and Schultz and refutes the plaintiffs’ causation claims.
March 13, 2023 Update: a new Bair Hugger infection lawsuit (Jones v. 3M Co., et al., 23-cv-603) was filed in the MDL in the District of Minnesota today. The plaintiff, Cheryl Jones, is an Alabama resident who underwent knee replacement surgery in April 2021 during which the Bair Hugger device was used. She subsequently developed a deep joint infection, which required her to undergo multiple additional surgeries on her knee.
February 12, 2023 Update: The first status conference in the newly reopened Bair Hugger class action MDL was held this week before Judge Joan Ericksen.
December 16, 2022 Update: The Bair Hugger class action MDL has formally been reopened. On December 14, 2022, 3M sent a letter to MDL Judge Joan Ericksen asking that the MDL proceedings be reopened and resumed. In the letter, 3M claimed that nothing has really changed and urged Judge Ericksen to fast-track a new round of bellwether trials for the start of 2024. Today, the plaintiffs responded with their own letter saying that new evidence has emerged (specifically a new study published in JAMA in 2022) that strengthens their position on causation.
November 26, 2022 Update: 3M will get some insurance coverage for Bair Hugger claims. A federal court in Minnesota ruled this week that 3M must only pay a single deductible for more than 5,000 Bar Hugger lawsuits. But the insurance company – Federal Insurance Co. is not on the hook for all of 3M’s attorneys’ fees and other defense costs in the warming device lawsuits because only a fraction of the claims fall within the insurance policy period.
May 18, 2022 Update: The Supreme Court rejected 3M’s appeal.
August 23, 2021 Update: Last week a federal appeals court reinstated 5,000 claims that had been dismissed and this litigation is back on. But few lawyers are taking new claims.
Should you bring a Bair Hugger lawsuit if you believe you suffered an infection from a Bair Hugger during surgery? Decide for yourself. But despite some early punches to the face for plaintiffs, there is still a reasonable chance these cases end well for plaintiffs. Let’s talk about these cases, what they are, where they are going, and what the prospects are that the 3M Bair Hugger cases reach a settlement.
Bair Hugger
A Bair Hugger device is a temperature management system that is used during surgery. The purpose of the invention is to help the body regulate the appropriate temperature. Bair Hugger Forced Air Warming Device is designed, manufactured, and marketed by Defendants 3M Company and Arizant Healthcare, Inc. There are more than 50,000 Bair Hugger FAWs in the United States.How does it work? The Bair Hugger is a portable heater/blower connected by a flexible hose to a blanket, typically positioned for the patient getting surgery. The Bair Hugger pushed hot air through a hose into a blanket specially made to work with the device. The hot air produced by Bair Hugger accumulates under the surgical drape covering the patient. This hot air escapes under the surgical drape below the level of the surgical table or over top of it.
So the Bair Hugger is designed to keep a patient’s body temperature normal during surgery by blowing hot air through a blanket. Keeping a patient warm is particularly useful during knee and hip replacement surgery because the procedures tend to be very long. The body loses heat increasingly throughout the surgery.
Another thing about metal hip and knee replacement surgery is that your body is particularly prone to infection. Why? The metal helps spread the infection.
Plaintiffs in the lawsuits argue that the device disrupts the air ventilation in the operating room, leading to infections, particularly in hip and knee surgeries, which have resulted in amputations and multiple surgeries. They also allege that 3M has been aware of the contamination issue since 2009.
Bair Hugger Lawsuit
So if you are not already familiar with this litigation, you know where this is going. The device is blowing bacteria on the patient. These germs are expelled from the interior of the Bair Hugger FAW blower by the outward airflow, traveling through the hose into the disposable blanket and escaping all over the operating table and the patient. If bacteria in a surgical site is not bad enough, the metal helps grease the wheels of further infection.
At the core of these claims is that the design of these blowers was flawed. Given the risks of blowing bacteria in the surgical area, plaintiffs’ lawsuits allege that the Bair Hugger should have been designed to prevent internal contamination and the emission of airborne contamination. One big problem for 3M will be a study that found that 96% of the Bair Hugger systems were dispersing inordinately excessive levels of contaminants.
This will also be a “what did you know and when did you know it?” lawsuit. The plaintiffs’ lawsuits will also contend that setting aside the design failure and the failure to test, the manufacturer knew or should have known of the risk of infection the Bair Hugger was causing and did nothing about it. The core of the issue is that the manufacturer was aware of the potential for infections but failed to warn patients and their healthcare providers. These lawsuits also claim that the manufacturer failed to take steps to improve the design of the device to prevent infections from occurring.
Plaintiffs’ experts have concluded the Bair Hugger can cause deep joint infections in exposed patients. They believe Bair Hugger creates convective currents that carry bacteria-laden particles from near the floor to the surgical site. The plaintiffs’ experts’ opinions are based on a comprehensive review of the relevant literature, their own independent experiments, a thorough examination of multiple sources of evidence, and internal 3M documents, which collectively lead to the conclusion that the Bair Hugger transmits particles and bacteria to the surgical site.
Bair Hugger Class Action
The Bair Hugger infection lawsuits were consolidated into a class action MDL in 2015. The MDL was assigned to Judge Joan Ericksen in the District of Minnesota. The Bair Hugger class action MDL eventually grew to over 5,000 individual plaintiffs from around the country. The first bellwether test trial in the MDL resulted in a defense verdict for 3M. A second bellwether trial was scheduled, but before it occurred, Judge Ericksen granted a motion for Summary Judgment filed by 3M on the grounds that the plaintiffs’ scientific evidence on the issue of causation was not legally sufficient.
Judge Ericksen’s ruling on the Summary Judgement motion resulted in the dismissal of all 5,000 pending cases in the Bair Hugger MDL. The plaintiffs appealed the ruling, however, and eventually, the U.S. Court of Appeals for the 8th Circuit overturned Judge Ericksen’s ruling. Although the 8th Circuit agreed that there were weaknesses in the causation evidence, it held that the evidence was strong enough to be admissible in court and, therefore, summary judgment was not appropriate.
3M appealed to the Supreme Court, but that appeal was denied. This effectively ended the appellate battle and reopened the Bair Hugger class action MDL. Bair Hugger infection lawsuits are now being filed in the MDL again, and Judge Ericksen will schedule another round of bellwether trials, which could yield drastically different results. Is it a concern to return to the same judge who wanted to dismiss all the cases? Of course. But these cases push forward in 2025, hoping for new momentum.
Bair Hugger Settlements
These cases may ultimately settle. But it is unrealistic to expect the settlements to reflect the real value of the victims’ pain and suffering.