• Posted December 4, 2023

'High Altitude' Simulations Might Shield Patients Ahead of Surgery

Surgery coming up? Mimicking the high-altitude breathing of mountaineers might make your procedure safer, a tiny study suggests.

It's a form of what surgeons call "prehabilitation:" Making a patient's body a bit fitter beforehand to withstand the risks and rigors of surgery.

Investigators found that exposing patients to reduced oxygen levels ("hypoxia") for a week spurred a rise in blood hemoglobin. The British researchers believe that could help prevent complications around surgery.

"We know that athletes can use hypoxic canopies over their bed to simulate altitude exposure and that altitude can induce performance benefits after two to three weeks even in people who are extremely fit," noted study lead author Dr. Thomas Smith, an anesthetist at King's College London.

"We were interested in whether this approach could also benefit older patients ahead of major surgery, who due to sedentary lifestyles and low levels of fitness, are more at risk of negative postoperative outcomes," he said in a college news release.

To test this theory, Smith's group first selected eight volunteers, averaging 64 years of age, who had sedentary "couch potato" lifestyles.

All were sent to live for two weeks at a special "hypoxic house" in Ireland, where room oxygen levels are tightly controlled.

During one week of the study, the eight volunteers breathed normal air, but in a second week they breathed air that had oxygen levels equivalent to flying at an altitude of 8,000 feet.

Special cardiopulmonary tests showed no overall improvement in aerobic fitness after breathing the low-oxygen air, but there was a spike in blood hemoglobin, the team reported.

Hemoglobin carries oxygen throughout the body, enabling it to perform better under stress.

Although more study is needed, "simulated altitude exposure may have potential advantages for older and sedentary patients" ahead of a surgery, Smith reasoned.

For example, patients might sleep at night for a few weeks in small "hypoxic canopy" tents that could be provided to patients, he explained.

The study was published recently in the journal Anaesthesia.

More information

There are more pre-surgical tips for patients at Washington University School of Medicine.

SOURCE: Kings College London, news release, Nov. 30, 2023