Safety concerns have been raised about the routine use of oxygen for patients in hospital settings, according to the authors of new guidelines.
Routine oxygen therapy was not recommended for hospital patients because the benefit was uncertain and there were clear harms, said the panel of experts in the British Medical Journal.
“Use the minimum amount of oxygen necessary”
Their advice is based on new evidence that too much oxygen increases risk of death and is part of the BMJ’s Rapid Recommendations initiative – to quickly produce guidance based on new evidence.
The authors noted that oxygen therapy was widely used in hospitals and it was usual care to give extra oxygen to sick patients, often with relatively little attention paid to when to start and stop it.
Guidelines also varied in their advice on when to give oxygen and how much to give, they said.
The authors highlighted that normal oxygen saturation in the blood was usually between 96% and 98%, but sick patients were often kept close to 100%.
However, they cited a recent evidence review published in The Lancet, which found that giving extra oxygen to hospital patients with normal oxygen levels increased mortality.
The researchers behind the review concluded that oxygen should be given conservatively, but they did not make specific recommendations on how to do it.
As a result, an international panel – made up of specialist doctors, a nurse, a surgeon, and patients – met to discuss this latest evidence and formulate a recommendation. The nurse who took part in the review was Jillian Siemieniuk, from Alberta Health Services in Calgary, Canada.
Having assessed the quality of evidence available, the authors made a “strong recommendation” to stop oxygen therapy in patients with a saturation of 96% or higher.
For patients who have had a heart attack or stroke, they suggest not starting oxygen therapy when levels are between 90% and 92% saturation. In addition, they strongly recommended not starting oxygen therapy when levels are at or above 93% saturation.
There was not enough evidence to say exactly when oxygen should be started for many other medical conditions such as infections, they noted.
For most patients, they said a target of 90 to 94% saturation seemed “reasonable” and was low enough to avoid harm. In all cases, they advised using the minimum amount of oxygen necessary.
The authors highlighted that, while their recommendations apply to most patients, they did not apply to surgical patients, babies, or patients with a few other uncommon conditions.
They also acknowledged that their recommendations may be altered as new evidence emerges.