Bair Hugger Lawsuit: MDL 2666 Status and Who Qualifies

The Bair Hugger is a forced-air warming system that blows warm air through a disposable blanket to keep patients' body temperature up during surgery. 3M made and sold it; its health care business, including Bair Hugger, was separated into a new company, Solventum, in 2024.

The plaintiffs allege that the warm air the device blows disrupts operating room airflow and can carry bacteria into the open surgical site, and that 3M knew of the risk and did not warn. Solventum's filings describe the cases as alleging that patients underwent joint arthroplasty, cardiovascular, and other surgeries and later developed surgical site infections due to the use of the Bair Hugger patient warming system. The most serious claims involve infected hip or knee implants that had to be removed, and some involve amputation.

3M and Solventum deny that the Bair Hugger causes infections. These are individual injury cases in a mass tort, not proven claims. Under the separation agreement, Solventum indemnifies 3M for uninsured Bair Hugger liabilities, manages the litigation, and pays legal expenses, while 3M remains the named defendant.

Forced-air warming is used to keep patients warm during surgery, and surgical site infections can have many causes, including the patient's own health, the procedure, and the operating room. Plaintiffs must show not just that an infection happened, but that the warming device was a cause, which is why expert testimony has decided so much of this litigation. You can compare other device and drug cases on our lawsuits to join page.

The federal cases are centralized as In re: Bair Hugger Forced Air Warming Devices Products Liability Litigation, MDL No. 2666, Case No. 0:15-md-2666, in the District of Minnesota before Senior Judge Joan N. Ericksen. The JPML created it on December 11, 2015.

The litigation has had unusual swings. In July 2019, the MDL court excluded several of the plaintiffs' causation experts and granted summary judgment for 3M in every pending case. On August 16, 2021, the Eighth Circuit reversed, reinstating almost 6,000 lawsuits. On August 17, 2021, the same court affirmed the defense verdict in Gareis v. 3M, the first federal bellwether trial.

Since the cases returned, the parties have been litigating additional MDL bellwether and state court cases. Solventum reports eight state court personal injury cases, including a multi-plaintiff case of amputees in Ramsey County, Minnesota, and a putative class action there seeking economic damages over use of the device in knee and hip replacements for medically obese patients since May 2017. During the second quarter of 2026, Solventum increased its Bair Hugger litigation accrual to its best estimate of probable loss, based on developments in the matter. It did not disclose the amount or announce a settlement.

The JPML's figures show 10,739 cases filed over the life of the MDL and 8,433 still pending on September 1, 2026, meaning more than 2,000 have been closed through dismissal, remand, or other resolution.

Attorneys generally screen for:

• Bair Hugger use during the surgery, which anesthesia or nursing records often document.
• A deep infection after surgery, especially a periprosthetic joint infection after hip or knee replacement.
• Serious treatment such as washout surgery, removal of the implant, a two-stage revision, long-term IV antibiotics, fusion, or amputation.
• Timing consistent with a surgical infection, typically within months of the operation.

You are less likely to qualify if the infection was superficial, if it cleared quickly with oral antibiotics, or if records show a different warming method. Other infection risk factors such as diabetes, obesity, or smoking do not automatically disqualify you, but the defense will raise them.

Joint replacement infections are the core of the litigation, but Solventum's description of the cases also includes cardiovascular and other surgeries. If you had a deep infection after a different kind of operation and the records show forced-air warming, it is still worth asking about.

If you had a joint replacement at a hospital years ago, the hospital may still hold the anesthesia and nursing records, but retention periods vary, so request them sooner rather than later. An attorney can help with the request.

There is no public settlement and no plaintiff bellwether verdict in the federal MDL, so there is no reliable average payout. If the cases resolve, value would likely track:

• the number of additional surgeries and whether the implant had to be removed;
• permanent outcomes such as joint fusion or amputation;
• medical costs and lost wages;
• pain and loss of mobility.

Solventum's decision to raise its accrual in 2026 signals that it considers a loss probable and estimable, but it is not a settlement and says nothing about individual amounts. Mass tort attorneys usually work on contingency. See class action vs. mass tort.

Amputation cases, like those in the Ramsey County multi-plaintiff suit Solventum describes, would be expected to be at the high end of any valuation, while infections cured with one washout surgery and antibiotics would be at the lower end.

The claims are state-law product liability claims: design defect, failure to warn, and negligence. The central battle has been over general causation, meaning whether reliable science shows the Bair Hugger can cause deep infections at all. The 2019 ruling excluded plaintiffs' experts; the 2021 Eighth Circuit reversal let that evidence back in, which is why thousands of cases revived.

The Gareis appeal shows the other side: the Eighth Circuit found the trial court did not abuse its discretion in excluding some design evidence or in allowing 3M's expert on operating-room airflow, and let the defense verdict stand. For more on how rulings like these shape an MDL, see what an MDL is.

The difference between the 2019 ruling and the 2021 reversal meant roughly 6,000 cases went from dismissed to revived, which shows how much these device cases depend on which experts a jury is allowed to hear.

Each case is governed by the plaintiff's state statute of limitations, commonly two or three years, often measured from when you knew or should have known your infection might be linked to the device. Because the litigation has been public since 2015, defendants may argue that older infections are already time-barred. Some states also have statutes of repose.

Wrongful death claims have their own deadlines, usually from the date of death. If your surgery and infection were recent, talk to an attorney promptly.

If a family member died after a post-surgical infection, the estate may have a wrongful death claim with its own deadline. For patients who had more than one surgery, each operation and infection may carry its own dates, so list them separately. Because the MDL has been open since December 2015, people whose infections happened long ago should expect defendants to challenge timing closely.

Not every Bair Hugger claim is in the federal MDL. Solventum's June 2026 filing describes several other proceedings:

• Eight state court personal injury cases, including a multi-plaintiff case of amputees in Ramsey County, Minnesota.
• A putative class action in Ramsey County seeking economic damages over use of the Bair Hugger in knee and hip replacement surgeries on medically obese people in Minnesota from May 2017 to the present.
• A putative class action in Ontario, Canada, served in June 2016, for Canadian residents who had joint, cardiovascular, and other surgeries and later developed surgical site infections they attribute to the device.

Solventum reported being the named defendant, through 3M, in approximately 8,400 U.S. lawsuits, which closely matches the JPML's count of 8,433 pending MDL cases.

What the Gareis appeal decided

The plaintiffs in the first bellwether, Gareis, lost at trial and appealed. On August 17, 2021, the Eighth Circuit affirmed, finding the trial judge did not abuse her discretion by excluding evidence of 3M's knowledge of the risks and utility of the Bair Hugger and evidence of alternative designs other than the TableGard, and that plaintiffs did not show they were prejudiced. It also upheld allowing 3M's expert to testify about operating-room airflow. The same week, a separate Eighth Circuit ruling revived thousands of other cases, which is why the litigation continued despite the Gareis loss.

Questions an attorney will likely ask

• What surgery did you have, where, and when?
• Does the anesthesia record show a forced-air warming device?
• When did infection symptoms start, and what organism grew in cultures?
• How many additional surgeries followed, and is the implant still in place?
• What other health conditions did you have at the time?

1. Request your surgical records, including the anesthesia record, which may list the warming device.
2. Gather infection records: cultures, imaging, and infectious disease consults.
3. Keep operative reports for every follow-up surgery.
4. Write a timeline of the original surgery, first symptoms, and each treatment.
5. Do not rely on payout promises. No settlement has been announced.

A case review usually takes a few minutes. If your situation fits what independent attorneys are handling, one may follow up and, with your permission, request the surgical and infection records. The anesthesia record is often the only document showing which warming device was used, so ask for it specifically when you request records. There is no charge for the review and no obligation.

Independent attorneys who handle Bair Hugger cases can review your records and state deadline. A free case review takes about two minutes. Related: the Olympus endoscope infection lawsuit, the port catheter lawsuit, and 3M earplug litigation.