Navigation Links
Method to Detect When Patients Wake During Surgery Fails to Impress
Date:8/18/2011

By Amanda Gardner
HealthDay Reporter

WEDNESDAY, Aug. 17 (HealthDay News) -- A newer technology intended to alert doctors when patients are regaining consciousness while under anesthesia is no better than conventional monitoring systems in lowering the incidence of "anesthesia awareness," new research shows.

In fact, the newer system -- which measures electrical activity in the brain and is known as bispectral index (BIS) monitoring -- actually picked up on fewer incidents than the standard system, which measures the amount of anesthesia when a patient exhales.

Anesthesia awareness takes place when a patient under general anesthesia can remember what happened during surgery. It occurs in up to 1 percent of high-risk patients, or 20,000 to 40,000 U.S. patients a year.

Researchers have pointed out that the standard system is also simpler and less expensive to use.

But that doesn't mean there isn't a place for the newer technology, said several scientists.

One expert said that BIS could be useful when used together with ETAC, which stands for "end-tidal anesthetic-agent concentration."

"This is not the be-all, end-all device, but I believe it's a useful piece of information used in conjunction with ETAC and everything else," said Dr. Mark D. Schlesinger, chairman of anesthesiology at Hackensack University Medical Center in New Jersey. "You need multiple pieces of information."

Generally, systems to monitor awareness have focused on the cardio-respiratory system while those monitoring the nervous system have lagged behind.

"I think most practitioners believe that [BIS] can be useful in certain situations," added Dr. Russell K. McAllister, an associate professor of anesthesiology at the Texas A&M Health Science Center College of Medicine and an anesthesiologist with Scott & White in Temple.

Those situations might include patients who are getting intravenous anesthesia -- which ETAC can't monitor -- or low-risk patients, who were not included in this study, said Dr. Devi E. Nampiaparampil, an assistant professor of anesthesiology and rehabilitation at NYU School of Medicine in New York City.

Neither Schlesinger, McAllister nor Nampiaparampil were involved with the study, which appears in the Aug. 17 issue of the New England Journal of Medicine.

Patients at high risk for anesthesia awareness can include those who have undergone trauma in an accident and have unstable vital signs, or someone who can't tolerate high levels of anesthesia, Schlesinger explained. This group of patients also includes those who regularly consume large quantities of alcohol and those taking sedatives or certain kinds of painkillers.

"[Anesthesia awareness] continues to affect substantial a number of patients and to be a cause of real distress and long-term consequences for those who experience it," said study author Dr. Michael Avidan.

Avidan marveled at the paucity of nervous system monitoring for anesthesia patients, compared to those that monitor the cardio-respiratory system.

"That's surprising because the nervous system is really the target of anesthesia," said Avidan, who is division chief of cardiothoracic anesthesia and cardiothoracic intensive care at Washington University School of Medicine in St. Louis.

This is the third trial of BIS in recent years, starting with a 2004 study that found that using BIS monitors could reduce awareness incidence by 82 percent. A 2008 trial by the same group of researchers found that BIS didn't perform as well as ETAC, leading the team to try a still larger trial.

For this study, the researchers randomized 6,000 patients at high risk for anesthesia awareness to either BIS-guided anesthesia or ETAC-guided anesthesia.

Seven patients (0.24 percent) in the BIS group recalled being aware during the procedure, compared to 2 (0.07 percent) in the ETAC group.

Why didn't a system that directly measures brain activity work better than standard procedures?

"You would think that brain monitoring would give you more information, [but] I think there are reasons why it didn't," said Nampiaparampil.

Anesthesia is given for three different purposes, she explained. One is to relax the patient's muscles, one is to foster amnesia and one is for pain relief.

"Those three functions may not be controlled by the same area of the brain and even with BIS . . . you may not be looking at all areas you need to in order to [ascertain awareness]," said Nampiaparampil.

Still, Avidan said he is a "strong proponent of working on ways that we can monitor the brain and try directly to monitor anesthesia rather than relying on more removed surrogate measures."

More information

A patient who experienced this phenomenon founded the Anesthesia Awareness Campaign.

SOURCES: Michael S. Avidan M.B., B.Ch., professor, anesthesiology and surgery, and division chief, cardiothoracic anesthesia and cardiothoracic intensive care, Washington University School of Medicine, St. Louis; Mark D. Schlesinger, M.D., chairman, anesthesiology, Hackensack University Medical Center, New Jersey; Russell K. McAllister, M.D., associate professor, anesthesiology, Texas A&M Health Science Center College of Medicine, and anesthesiologist, Scott & White, Temple; Devi E. Nampiaparampil, M.D., assistant professor, anesthesiology and rehabilitation, NYU School of Medicine, and chief, Interventional Pain Management, VA New York Harbor Healthcare System; Aug. 17, 2011, New England Journal of Medicine


'/>"/>
Copyright©2010 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Live with Regis and Kelly Reveal A REVOLUTIONARY Pain Relief Method
2. Two Surgical Methods Equally Successful for Prostate Cancer
3. Psychiatrys main method to prevent mistaken diagnoses of depression doesnt work: NYU study
4. New testing method hints at garlics cancer-fighting potential
5. MSU scientists develop more effective method of predicting lead-poisoning risk
6. Blood Draw Dilemma: New Summit Health Article Helps Employers Choose the Best Screening Method
7. Worlds most useful tree provides low-cost water purification method for developing world
8. FDA, FSIS, CDC Collaborate on Methods to Measure Success of Food Safety Programs
9. Los Angeles Hair Transplant Cosmetic Surgeon Corrects Bad Hair Transplants With New Hair Restoration Method
10. An improved method for calculating tumor growth
11. New method to grow arteries could lead to biological bypass for heart disease
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Method to Detect When Patients Wake During Surgery Fails to Impress
(Date:3/28/2017)... ... March 28, 2017 , ... A recent Bellwether Education Partners’ ... the field must first improve teacher preparation program design. It then asserts that ... that decades of input- and outcome-based research has failed to improve teacher education. ...
(Date:3/28/2017)... ... March 28, 2017 , ... India’s ... technology to directly address the resolution to globally reduce the harmful use of ... compound of FDA and TTB approved ingredients that when infused into alcohol, renders ...
(Date:3/28/2017)... WASHINGTON, DC (PRWEB) , ... March 28, 2017 ... ... call on elected representatives in state legislatures and Congress to protect parental rights ... the public health and safety in America. , The demonstration coincides with a ...
(Date:3/28/2017)... ... March 28, 2017 , ... ... of all holidays (IBT World Travel Trends Report). As travelers visit both urban ... range in temperatures, and prolonged sun exposure. In response, the outdoor industry has ...
(Date:3/28/2017)... ... 2017 , ... Via Oncology, the leading provider of oncology ... public-facing tool for analyzing the costs of various drug regimens in cancer care. ... patients, providers, insurers and pharmaceutical companies about the estimated costs of treatment options. ...
Breaking Medicine News(10 mins):
(Date:3/29/2017)... DUBLIN , Mar 29, 2017 Research ... Global Market - Forecast to 2023" report to their offering. ... The ablation ... CAGR to reach $20,995.5 million by 2023. Ablation ... wide range of purposes, from cancerous or diseased tissue removal, to ...
(Date:3/29/2017)...  Spiral Therapeutics, Inc. today announced the signature ... for the worldwide exclusive rights to Bionure,s lead ... of otolaryngology for aggregate payments of up to ... provides Spiral with the option to license two ... Under the terms of the agreement, Spiral will ...
(Date:3/29/2017)... 2017   Royal Philips (NYSE: PHG, ... and PathAI, a company that develops artificial intelligence ... to develop solutions that improve the precision and ... diseases. The partnership aims to build deep learning ... artificial intelligence to be applied to massive pathology ...
Breaking Medicine Technology: