An operating room averages about 66 decibels, a soundtrack somewhere between ordinary conversation and a nearby vacuum cleaner. Patients under general anesthesia aren’t consciously aware of it, which raises a reasonable question: does the noise still matter?
Researchers decided to test that instead of assuming the answer. They randomly assigned 192 adults undergoing minimally invasive gynecologic surgery to wear headphones during their operations or go without. Then they tracked nausea and vomiting afterward, and the two groups had noticeably different experiences.
Researchers presented the findings at the American Society of Anesthesiologists’ ANESTHESIOLOGY 2026 meeting in San Diego, held October 16 to 20.
A simple pair of headphones making that kind of difference sounds almost too good to be true, and even the researchers don’t know exactly why it seemed to help.
The Numbers Behind the 32% Drop
The 32% comes from a gap between two rates, and both are worth seeing.
Within 48 hours of surgery, 35.4% of patients who wore headphones experienced postoperative nausea and vomiting (PONV), the queasiness and throwing up that can follow an operation. In the group without headphones, the rate was 52.1%. The American Society of Anesthesiologists calls that a 32% lower risk.
It’s a relative reduction, not a 32-percentage-point difference. Put another way, roughly 17 fewer people in every 100 developed PONV in the headphone group. Those who wore headphones also had less severe symptoms during the first 24 hours, with no increase in adverse events reported.
And this isn’t always a minor inconvenience. PONV can lead to dehydration, additional medication, slower recovery, and longer stays in the recovery room.
Related: 8 Common Health Mistakes Doctors Wish Americans Would Stop Making
These Patients Already Had Anti-Nausea Drugs
The headphones were tested on top of the usual medication.
Both groups received the same general anesthesia and preventive drugs: dexamethasone during anesthesia and palonosetron at the end of surgery. Their anesthetic regimen included sevoflurane and opioids, which matters because PONV guidelines identify volatile anesthetics and postoperative opioids as major risk factors. Patients with severe PONV could receive an additional dose of palonosetron.
So the question wasn’t whether headphones could replace medication. The team wanted to know whether reducing noise might add benefit, at a time when direct evidence linking headphones to lower PONV was lacking. That made the trial exploratory.
Lead author Huayue Liu, M.D., an anesthesiologist at the First Affiliated Hospital of Soochow University, says the findings suggest another possible tool for anesthesiologists, without adding a drug.
Patients Wore Industrial-Style Hearing Protectors
A trial protocol published in 2025 names the exact model and shows how the team kept the test fair.
The American Society of Anesthesiologists described commercially available, over-the-head noise-canceling headphones. The team’s protocol, published in BMC Anesthesiology, identifies them as 3M Peltor X5A hearing protectors, rated for 37 decibels of noise reduction. Patients wore them from induction of anesthesia until the end of surgery.
That distinction is very important. The trial provides no evidence that personal headphones would produce the same result, or that patients could bring their own into the operating room.
An independent researcher generated the randomization sequence. Once anesthesia began, a therapeutic towel covered every participant’s head and ears, concealing who the protectors had. Surgeons, nurses, follow-up assessors and statisticians remained unaware of group assignments until the final analysis.
Patients couldn’t tell either, because they were anesthetized before the headphones were fitted.
Why Would Less Noise Help?
Researchers have a hypothesis, but nothing has been proven.
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Liu points to a curious possibility: general anesthesia prevents conscious awareness, but the brain may still process some sound. The team describes the headphones as a form of noise isolation, intended to test whether operating-room sound might influence recovery.
Noise during abdominal surgery often exceeds 55 decibels, the researchers note, and excessive sound can interfere with team communication and distract clinicians. Neither observation explains the nausea difference.
The connection between noise, PONV, and surgical performance remains uncertain. Liu wants future research to measure exposure and bodily responses directly: “Future studies should measure the amount of noise patients are exposed to during surgery and how their brains and bodies respond to better understand whether and how sound may affect PONV.”
The Patients Were At High Risk To Begin With
Nausea is common after this kind of surgery, and the trial left out a long list of people.
All participants were women ages 18 to 65 undergoing laparoscopic gynecologic surgery, for which the researchers cite PONV rates ranging from 20% to 80%.
The study excluded anyone pregnant or breastfeeding, as well as people with significant hearing loss, vestibular disease, impaired gastric motility, serious liver or kidney dysfunction, or recent use of anti-nausea or psychotropic drugs.
So the findings can’t yet be extended to other operations, other patients, nausea at home, or headphones worn in the recovery room.
The effect was smaller than expected, too. Their sample-size calculation assumed a fall from about 45% to 25%, a 20-point drop. The observed gap was narrower, and the trial took place at a single center.
Nausea Was Only The Beginning
The study was set up to track much more than nausea, and those results are still pending.
The team also planned to track rescue anti-nausea medication, pain scores, opioid use, time to extubation, recovery-room and hospital stays, satisfaction, sleep, complications, and recovery-quality scores at 24 hours, 48 hours, and 30 days. So far, the findings cover nausea, symptom severity, and safety. Other results may follow in the full paper.
Earlier studies linked noise isolation with less pain and lower opioid use. A 2026 systematic review and meta-analysis also examined pain, opioid use, and quality of recovery.
Those earlier findings give researchers another reason to investigate the effects of operating-room noise, but the nausea result still needs confirmation elsewhere. If it holds up in other trials, hospitals may have to ask how loud an operating room needs to be in the first place.
Have you ever had a rough time with nausea after a procedure, and did anything help?
