If you developed a deep-joint infection after a hip or knee replacement in which a 3M Bair Hugger warming blanket was used, here is who may qualify in MDL 2666 — the surgical-device litigation the Eighth Circuit revived after it was first dismissed.
Allegations Only · No Settlement Yet
This page describes ongoing litigation and an investigation. The statements below are unproven allegations. 3M denies the allegations and disputes that the device causes infection; no company has been found liable, no settlement has been finalized, and eligibility depends on the facts of each case. This page is informational and is not legal or medical advice.
What Is This About?
Did you have a hip or knee replacement — or another orthopedic implant surgery — in which a Bair Hugger forced-air warming blanket was used, and then develop a deep infection around the new joint? If so, you may be eligible to speak with counsel about your legal options.The federal cases are consolidated in multidistrict litigation known as MDL 2666, In re: Bair Hugger Forced Air Warming Devices Products Liability Litigation, before Judge Joan N. Ericksen in the U.S. District Court for the District of Minnesota. Plaintiffs allege that the device — manufactured by Arizant Healthcare, now owned by 3M — can spread bacteria into an open surgical wound. 3M denies the claims and disputes the underlying science.
The claims are allegations that have not been proven in court. This litigation has an unusual history: it was dismissed at the trial-court level and then revived on appeal.
What Is the Bair Hugger and What Do the Lawsuits Allege?
The Bair Hugger is a forced-air (convective) patient-warming system: a disposable blanket connected to a heater-blower unit that circulates warm air over a patient to maintain body temperature during and after surgery. Keeping a surgical patient warm is a recognized standard of care.Plaintiffs allege, however, that the device's forced-air current disrupts the sterile laminar airflow of the operating room, stirring up airborne contaminants and depositing bacteria into the open surgical site. They allege this can cause deep periprosthetic joint infections (PJI) — infections deep around an implanted hip or knee. The alleged consequences include additional surgery, implant removal, prolonged intravenous antibiotics, and in severe cases amputation. The legal theories are product defect and failure to warn. 3M disputes the allegations and contests general causation — that is, whether the device is capable of causing these infections at all.
Who May Qualify?
You may qualify to speak with counsel if you underwent an orthopedic implant surgery — most commonly a hip or knee replacement — in which a Bair Hugger forced-air warmer was used and you later developed a deep-joint (periprosthetic) infection. Related outcomes plaintiffs describe include:• Revision surgery to treat the infection
• Removal of the implant (explant)
• Prolonged antibiotic treatment
• Amputation in severe cases
Eligibility depends on the surgery, the infection diagnosis, and the facts of your case. Helpful evidence includes operative and anesthesia records (which may note the warming device used), infection and culture results, and records of any revision surgery. Statutes of limitations vary by state, so anyone considering a claim should consult an attorney promptly.
Dismissed, Then Revived: The Litigation's History
The Bair Hugger MDL took an unusual path:• Around 2017 to 2019, the MDL court excluded the plaintiffs' general-causation medical experts and then granted 3M summary judgment, effectively ending the cases at the trial-court level.
• In August 2021, the Eighth Circuit Court of Appeals reversed the exclusion of those experts and vacated the summary judgment in In re Bair Hugger (Amador v. 3M), holding that the perceived weaknesses in the experts' opinions went to the weight a jury should give them, not to whether they could be heard at all.
• In 2022, the U.S. Supreme Court declined to hear 3M's appeal, leaving the revival in place.
Since the remand, the cases have returned to active status in the MDL, a pool of bellwether trial-candidate cases has been worked up, and court-supervised settlement discussions have proceeded under a special master. As of mid-2026 no global settlement has been announced, and roughly 8,400 cases remain pending, making it one of the largest MDLs in the country.
Frequently Asked Questions
What is the Bair Hugger lawsuit about?
Plaintiffs allege that the 3M / Arizant Bair Hugger forced-air warming device, used to keep patients warm during surgery, disrupts sterile operating-room airflow and deposits airborne bacteria into open surgical sites — allegedly causing deep-joint (periprosthetic) infections in hip and knee replacement patients. These are unproven allegations, and 3M disputes them.
Who may qualify for a Bair Hugger lawsuit?
The claims generally involve patients who had a hip or knee replacement (or other orthopedic implant surgery) where a Bair Hugger forced-air warmer was used and who later developed a deep periprosthetic joint infection — sometimes requiring revision surgery, implant removal, prolonged antibiotics, or in severe cases amputation. Eligibility depends on the facts of each case.
Wasn't the Bair Hugger litigation dismissed?
The MDL court excluded the plaintiffs' general-causation experts and dismissed the cases around 2017 to 2019, but in August 2021 the Eighth Circuit Court of Appeals reversed that ruling and revived the litigation, and the U.S. Supreme Court declined to hear 3M's appeal in 2022. The cases returned to the MDL and remain active.
Is there a Bair Hugger settlement?
No. As of mid-2026 there is no global settlement. Court-supervised settlement discussions have continued under a special master, but no resolution has been announced and no claim form exists.
Related Mass Torts & Sources
• Bard / Davol hernia mesh lawsuit (MDL 2846) — another large medical-device MDL.• Covidien / Parietex hernia mesh lawsuit (MDL 3029) — a companion device MDL.
• Philips Respironics CPAP / BiPAP recall settlement — a $479M medical-device economic-loss settlement.
Primary sources: U.S. Judicial Panel on Multidistrict Litigation (JPML) pending-MDL statistics; the U.S. District Court for the District of Minnesota MDL 2666 docket; and the Eighth Circuit's 2021 opinion in In re Bair Hugger (Amador v. 3M).
Important Disclosures
This page is for general informational purposes and does not constitute medical or legal advice. You should consult a qualified attorney about your individual situation. OpenClassActions.com is not a law firm and is not a claims administrator, and this page does not create an attorney-client relationship.Free settlement alerts
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