Monthly Archives: November 2014

New clue to how anesthesia works

Anesthesiology_Thoracic Surgery_Neurosurgery

Anesthesia, long considered a blessing to patients and surgeons, has been a mystery for much of its 160-plus-year history in the operating room.

No one could figure out how these drugs interact with the brain to block pain and induce a coma-like, memory-free state. The debate has divided the anesthesia research community into two camps: one that believes anesthetics primarily act on the cell membrane (the lipid bilayer) of nerve cells, perhaps altering it to the point that embedded proteins cannot function normally. The other says the membrane proteins themselves are altered directly by anesthetics.

Now there is new evidence supporting the latter position. A team of researchers from Weill Cornell Medical College has found that it is the proteins that are affected by commonly used anesthesia. Specifically, activity of ion channel proteins that are important for cell-to-cell communication is markedly reduced when anesthetics are applied, the researchers report in The Journal of General Physiology.

“This is, to our knowledge, the first demonstration that anesthetics alter the function of relevant ion channels without altering properties of the cell membranes,” says the study’s lead investigator, Dr. Hugh C. Hemmings, Jr., professor and chair of anesthesiology at Weill Cornell, who worked in close collaboration with Dr. Olaf S. Andersen, a lipid bilayer expert and professor of physiology and biophysics at Weill Cornell, who has developed methods to quantify the membrane-perturbing effects of drugs and other molecules.

Importantly, Drs. Hemmings and Andersen note, the studies tested clinically relevant concentrations of isoflurane, a widely used anesthetic. Previous studies that found the membrane was altered used much higher doses of isoflurane–concentrations that would never be used in patients.

The distinction matters, says first author Dr. Karl Herold, a research associate in the Department of Anesthesiology who performed and analyzed the experiments.

“Drugs are not perfect–they always have side effects,” Dr. Herold says. “You can only improve drugs if you know how they work, which means that you need to know when drugs have non-specific or undesired membrane effects,” Dr. Andersen adds.

“Now that we have a basic understanding of how anesthetics affect cells in the central nervous system, we have knowledge to improve them,” he says. “In the future, we may be able to design anesthetics that do just what we want them to do, and not what we don’t.”

http://www.medicalnewstoday.com/releases/285514.php

 

 

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Pain and anxiety relief for cancer inpatients

Anesthesiology_Pain Management

Pain is a common symptom of cancer and side effect of cancer treatment, and treating cancer-related pain is often a challenge for health care providers.

The Penny George Institute for Health and Healing researchers found that integrative medicine therapies can substantially decrease pain and anxiety for hospitalized cancer patients. Their findings are published in the current issue of the Journal of the National Cancer Institute Monographs.

“Following Integrative medicine interventions, such as medical massage, acupuncture, guided imagery or relaxation response intervention, cancer patients experienced a reduction in pain by an average of 47 percent and anxiety by 56 percent,” said Jill Johnson, Ph.D., M.P.H., lead author and Senior Scientific Advisor at the Penny George Institute.

“The size of these reductions is clinically important, because theoretically, these therapies can be as effective as medications, which is the next step of our research,” said Jeffery Dusek, Ph.D., senior author and Research Director for the Penny George Institute.

The Penny George Institute receives funding from the National Center of Alternative and Complementary Medicine of the National Institutes of Health to study the impact of integrative therapies on pain over many hours as well as over the course of a patient’s entire hospital stay.

“The overall goal of this research is to determine how integrative services can be used with or instead of narcotic medications to control pain,” Johnson said.

Researchers looked at electronic medical records from admissions at Abbott Northwestern Hospital between July 1, 2009 and December 31, 2012. From more than ten thousand admissions, researchers identified 1,833 in which cancer patients received integrative medicine services.

Patients were asked to report their pain and anxiety before and just after the integrative medicine intervention, which averaged 30 minutes in duration.

Patients being treated for lung, bronchus, and trachea cancers showed the largest percentage decrease in pain (51 percent). Patients with prostate cancer reported the largest percentage decrease in anxiety (64 percent).

Adapted by MNT from original media release

http://www.medicalnewstoday.com/releases/285107.php

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