Anesthesia and surgery can cause temporary or permanent brain damage. Surgical complications can be caused by free radicals that occur during anesthesia or during the surgical process itself.
Some of the mechanisms of neurologic injury caused by anesthesia and surgical procedures have been identified in the scientific literature. There are nutrients and drugs that can be taken ahead of time that may help prevent these problems.
For example, during open-heart surgery, free radicals have been identified as a primary culprit in preventing the reestablishment of a regular heart rhythm, and in causing the common complication of pancreatitis.
A study was conducted on 30 patients undergoing vascular surgery for abdominal aortic aneurysm or obstructive aortoiliac disease. Patients in group one were treated with coenzyme Q10 (150 mg a day) for seven days before the operation. Those in group two received a placebo. The results showed that markers of free radical activity and tissue damage (i.e. malondialdehyde, conjugated dienes, creatine kinase and lactate dehydrogenase) were significantly lower in patients who received coenzyme Q10 than in the placebo group. A decrease of plasma malondialdehyde correlated positively with a decrease in both creatine kinase and lactate dehydrogenase. The doctors concluded that pre-treatment with coenzyme Q10 may play a protective role during routine vascular procedures by attenuating the degree of peroxidative free radical damage.
Some forms of anesthesia administered during surgical procedures that can cause temporary reduced blood flow may lead to significant free radical damage to cells. A study was performed to assess the administration of Vitamin-E during severe anesthesia. The administration of Vitamin-E produced a statistically significant decrease in the content of peroxidation products in the blood.
A growing body of evidence supports the role of free radicals in delayed functional and metabolic myocardial recovery following cardiopulmonary bypass in humans. A clinical study was designed to evaluate the extent that ginkgo extract could inhibit reperfusion-induced lipid peroxidation, ascorbate depletion, tissue necrosis and cardiac dysfunction. Patients received either ginkgo extract (320 mg a day) or a matching placebo before surgical intervention. Plasma samples were obtained up to eight days post-operatively, from the peripheral circulation and the coronary sinus, at crucial stages of the operation (i.e., before incision, during ischemia, and within the first 30 minutes after unclamping). Upon aortic unclamping, ginkgo extract inhibited the formation of free radicals, significantly reduced the delayed leakage of myoglobin, preserved the ascorbic acid pool, and had an almost significant effect on ventricular myosin leakage. The surgeons concluded that these results demonstrate the usefulness of adjuvant (assisting) ginkgo extract therapy in limiting oxidative stress in cardiovascular surgery. They discussed the possible role of highly bioavailable terpene constituents of the drug.
Other nutritional substances that may be of use include the aminio acid acetyl-L-carnitine.
You may consider taking melatonin every night for one week before your surgery. Melathion is a "sleep" hormone and antioxidant. An additional dose of 10 mg might also be taken just before anesthesia is administered to provide further protection against anesthesia and surgery-induced complications. Research has shown that melatonin given prior to anesthesia protects cells throughout an animal's body (but especially in the brain) against ischemic injury caused by lack of blood flow.
Some surgeons ask their pre-surgical patients to avoid aspirin and nutrients that may promote excessive bleeding during surgery. Ginkgo biloba and some other nutrients including Vitamin-E, can inhibit abnormal blood clotting and may cause excessive bleeding during and after surgery. For some surgical procedures, excessive bleeding can be a problem, but experienced surgeons should be able to deal with this.
On the other hand, a significant risk factor during and after surgical procedures and long hospital stays is the development of abnormal blood clots inside blood vessels that can cause a stroke, heart attack or a lethal pulmonary embolism.
Published studies have shown that when open-heart surgery patients take antioxidants before surgery, fewer complications develop. There are contradictions in the scientific literature as to whether or not Vitamin-E and other antioxidants cause enough excessive bleeding to create a problem. But when you consider the neurologic benefits, the protection against free radicals and abnormal blood-clot formation, and the overall health benefits these nutrients provide, you (and your physician) may choose to include these nutrients as part of your pre-surgery preparations.
July 18, 2005 — Since the beginning of modern medicine, doctors who administer anesthesia have largely confined their worries to the period beginning when patients are sedated and ending when they're fully awakened.
Now, two startling studies suggest that the effects of anesthesia linger for a year or longer, increasing the risk of death long after the surgery is over and the obvious wounds have healed.
"We don't know whether the things we do really have an effect that lasts a very long period of time, but there is enough evidence to suggest it might," says Dr. David Gaba, a professor of anesthesiology at Stanford University School of Medicine. "Even if it's a subtle and fairly uncommon phenomenon, it could affect an awful lot of people."
About 20 million Americans undergo surgery with general anesthesia each year.
Worries about the long-term effect of anesthesia -- and the demands for additional studies -- began to emerge recently when two research groups published papers linking deep sedation and an increased risk of death in the year or two after surgery.
One study, presented last fall at the American Society of Anesthesiologists annual meeting by Swedish researchers, showed that the duration spent under deep anesthesia was a significant risk factor for predicting death up to two years after surgery. Although the patients in the study were undergoing noncardiac surgery, most deaths resulted from heart attacks or cancer.
The other study, published in the journal Anesthesia & Analgesia in January by Duke University researchers, found that longer amounts of time spent under deep sedation increased the risk of death in the year following surgery. The patients in the Duke study underwent major, noncardiac surgery with general anesthesia, and again, deaths in the first year after surgery were primarily from heart attacks or cancer.
Some experts suggest that anesthesia and surgery may ignite a cascade of inflammation in the body that can aggravate heart, respiratory, cancer conditions or dementia.
According to the leading theory, surgery and anesthesia trigger the release of stress hormones, such as norepinephrine, that in turn activate inflammatory responses in the body and undermine the workings of the immune system. Inflammation is known to worsen many diseases, including heart disease, cancer, even dementia.
Since the first studies were published, newer research has suggested that noncardiac surgery with anesthesia also can cause a cognitive decline in some elderly people up to two years after the surgery, says Dr. Terri Monk, a professor of anesthesiology at Duke who led the study.
"Neither surgery nor anesthesia is a natural thing," Gaba says. "What some people suspect -- but there is still not much evidence for -- is there could be people whose inflammation processes don't come back to normal after surgery but stay revved up for a very long time."
Many patients who undergo heart bypass surgery suffer a significant and, it turns out, long-lasting loss of brain power, a study suggests.
Doctors have known that people often lose some of their mental sharpness immediately after a heart operation, but many seemed to recover fairly quickly. The new study, however, found that this recovery is short-lived.
The study looked at 261 patients who were on a heart-lung machine during bypass surgery. It found that five years after the operation, 40 percent showed a 20 percent drop in mental ability. That loss is similar to what a person normally goes through between the ages of 40 and 60.
Doctors do not know for sure why this mental loss happens, or even whether the operation causes it. For example, it might be that people whose arteries need to be replaced already have damaged blood vessels in their brains as well. The loss might also have something to do with being put on a heart-lung machine, which circulates blood through the patient's body during surgery.
An estimated 400,000 people a year are put on heart-lung machines for a bypass operation in the United States. The findings suggest that 160,000 of them risk losing some of their mental ability.
Dr. Mark F. Newman, who led the study published in Thursday's New England Journal of Medicine, noted that many patients in the Duke University study might not have lived five years without the operation.
"Now it's a matter of fine-tuning" the operation "to improve the quality of life as well as the length of life," he said.
Moreover, the people who lost mental ground in this study might have lost brain power faster anyway, said Dr. Irving L. Kron, chief of cardiac and thoracic surgery at the University of Virginia School of Medicine.
"It may be that the stress of the operation brings things out or pushes things along that were there to start with," Kron said.
Newman said other research appears to indicate that there are fewer problems with the brain after bypass operations done without the heart-lung machine.
Participants in the latest study took tests in memory, attention, concentration and manual dexterity five times: before the operation, when they left the hospital, and six weeks, six months and five years later.
Fifty-six percent did significantly worse when they were released from the hospital than when they were admitted.
Nearly half of those people were back up to pre-operation levels when tested six months after the operation. But at the five-year mark, most were back down to the levels measured when they were leaving the hospital.
Older people and those with the least education were the most likely to have lower scores five years later.
People who did not show any losses just after the operation were in equally good shape five years later.
The bypass operations took place from 1989 through 1993, and the last five-year tests were given in 1998.
Doctors are more aware of problems which can cause brain damage than they were when those bypasses were done, and improved techniques "will reduce or have reduced neurocognitive dysfunction," Newman said.
"I think our technology is continuing to improve," he said.
Copyright 2001 The Associated Press.