Featured Research

from universities, journals, and other organizations

High oxygen levels after surgery linked to increased long-term risk of death

Date:
September 25, 2012
Source:
International Anesthesia Research Society (IARS)
Summary:
Patients given high concentrations of inhaled oxygen during and after cancer surgery may be at higher long-term risk of death, according to a new report.

Patients given high concentrations of inhaled oxygen during and after cancer surgery may be at higher long-term risk of death, according to a report in the October issue of Anesthesia & Analgesia, official journal of the International Anesthesia Research Society (IARS).

Related Articles


Although preliminary, the study by Dr Christian S. Meyhoff of Copenhagen University Hospital and colleagues provides new evidence on possible risks -- in addition to previous data questioning the benefits -- of administering 80 percent oxygen to patients undergoing major surgery.

80 Percent Oxygen Linked to Higher Mortality Two Years after Cancer Surgery

The researchers evaluated long-term follow-up data from the PROXI study -- a randomized clinical trial performed to evaluate the effects of high concentrations of inhaled oxygen on infection rates after surgery. About 1,400 patients undergoing abdominal surgery were randomly assigned to receive either 80 percent or 30 percent oxygen in the perioperative period: during surgery and for two hours afterward.

In contrast to previous results, the original PROXI study found no difference in the risk of surgical wound infections. There was also a trend toward an increased short-term risk of death with 80 percent oxygen: 4.4 percent, compared to 2.9 percent in patients receiving standard treatment with 30 percent oxygen.

The increase in mortality was not statistically significant. However, it was enough to prompt a follow-up study to determine whether there was any real increase in the risk of death among patients receiving high concentrations of inhaled oxygen -- not only in the short term, but also in the subsequent months and years.

At one to three years after surgery, there were more deaths in the high-oxygen group. The long-term mortality rate was 23.2 percent for patients assigned to 80 percent oxygen, compared to 18.3 percent in the 30 percent oxygen group.

After adjustment for other factors, the difference was significant only for patients undergoing cancer surgery. In this group, the use of 80 percent oxygen was associated with a 45 percent increase in the risk of death. For patients undergoing other types of abdominal surgery, there was no difference in mortality between groups.

The long-term difference in mortality was surprising, because it appeared unrelated to any immediate harmful effects of 80 percent oxygen. (Breathing high concentrations of oxygen can cause harmful effects on the lungs in some cases.) The authors speculate on some possible mechanisms by which high oxygen concentrations could specifically affect the behavior of cancers, potentially increasing the risk of recurrence.

Dr Meyhoff and coauthors emphasize the preliminary nature of their findings -- the study was not designed to detect a difference in long-term mortality risk between 80 percent and 30 percent oxygen. They write, "Further studies are required before an association between perioperative hyperoxia and long-term mortality is established beyond reasonable doubt."

In the meantime, the findings add concerns over long-term mortality to the original PROXI results showing no reduction in infections among patients assigned to high concentrations of inhaled oxygen. The researchers conclude, "Until a clinical benefit of 80 percent perioperative oxygen is well-documented, we recommend abstaining from administering [oxygen concentrations] above what is needed to maintain sufficient arterial oxygen saturation."


Story Source:

The above story is based on materials provided by International Anesthesia Research Society (IARS). Note: Materials may be edited for content and length.


Journal Reference:

  1. Christian S. Meyhoff, Lars N. Jorgensen, Jψrn Wetterslev, Karl B. Christensen, Lars S. Rasmussen. Increased Long-Term Mortality After a High Perioperative Inspiratory Oxygen Fraction During Abdominal Surgery. Anesthesia & Analgesia, 2012; 115 (4): 849 DOI: 10.1213/ANE.0b013e3182652a51

Cite This Page:

International Anesthesia Research Society (IARS). "High oxygen levels after surgery linked to increased long-term risk of death." ScienceDaily. ScienceDaily, 25 September 2012. <www.sciencedaily.com/releases/2012/09/120925114345.htm>.
International Anesthesia Research Society (IARS). (2012, September 25). High oxygen levels after surgery linked to increased long-term risk of death. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2012/09/120925114345.htm
International Anesthesia Research Society (IARS). "High oxygen levels after surgery linked to increased long-term risk of death." ScienceDaily. www.sciencedaily.com/releases/2012/09/120925114345.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Experimental Ebola Vaccine Shows Promise In Human Trial

Experimental Ebola Vaccine Shows Promise In Human Trial

Newsy (Nov. 27, 2014) — A recent test of a prototype Ebola vaccine generated an immune response to the disease in subjects. Video provided by Newsy
Powered by NewsLook.com
Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) — Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
Today's Prostheses Are More Capable Than Ever

Today's Prostheses Are More Capable Than Ever

Newsy (Nov. 26, 2014) — Advances in prosthetics are making replacement body parts stronger and more lifelike than they’ve ever been. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins