Nutrition Before Surgery Dr Leow

NUTRITION

Nutrition’s impact on surgery By Dr George Leow Chee Seng Despite knowing that even a single vitamin deficiency can affect the immune system compromised by surgery, a recent study has found that many patients are still facing unnecessarily higher risks – because of their poor diets.

F

or more than 40 years, we have known that malnutrition greatly increases surgical mortality – with malnourished patients being ten times more likely to die soon after surgery.

To illustrate the previously unrecognised prevalence of this condition, it would be good to draw on the conclusions of a most enlightening study done some years ago.

Unfortunately, most of us are deluded into thinking our bodies look alright and that a malnourished person would look more like an Ethiopian refugee. But the true fact is that you can be malnourished and obese at the same time.

The study included a careful survey of surgical patients admitted to the hospital and found that 44% of the patients had general malnutrition on admission. This means that the patients were under-nutritioned long before needing surgery and coming to the hospital.

Taking a cue from the word “undernourished”, a new term has been coined to describe this syndrome – “under-nutritioned”. It is an important term that has begun to gain medical attention because it has been shown that people with even a single vitamin deficiency can have a poorly functioning immune system. Looks, indeed, can be deceiving.

Even worse, 75% of the patients admitted to an intensive care unit were found to be undernutritioned. This put the patients in even greater danger because their bodies and immune systems were placed under much greater stress. The sad irony is that such stress is a tremendous drain on nutrition at a time when the patient’s nutritional status needs to be better – to improve the odds for survival and post-surgical recovery. If such a prognosis wasn’t already bad enough, the study also uncovered another even more shocking finding – that 69% of the patients actually experienced a deterioration in their nutritional status while in the hospital; thus pointing to a rather sad indictment of hospital nutrition. Deficiency effects Another study involving a number of hospitals found that 38% of patients had obvious vitamin deficiencies and even a larger percentage was marginally deficient. These statistics were worrying because patients

58

MAR/APR 2009 • OH!

NUTRITION with marginal nutritional deficiencies are at a significantly higher risk of complications, especially in terms of poor wound healing and suffering potentially higher rates of infections. Most bleeding tendencies following surgery are minimal two days after the operation. This means you can safely resume taking your nutritional supplements. The only contraindication would be if you were receiving blood-thinning medications. In that case, I would avoid using vitamin E in doses over 200 international units (IUs), even though bloodthinning effects are rare below 1,000 IUs. Several supplements can thin the blood (and affect coagulation) and they include ginkgo, garlic ex tract, quercetin, curcumin, and high-dose vitamin E (greater than 1,000 IUs). But this concern is more apparent than real as, in general, the blood-thinning effect of these supplements is no more than that of taking one aspirin tablet a day. Magnesium factor Maintaining adequate magnesium levels is especially important in preventing surgical and post-surgical complications. Magnesium is one of those nutrients that seem to have an unlimited list of benefits. In addition to playing a role in more than 300 enzymes, it regulates blood flow, protects brain cells, protects the heart muscle, reduces the risk of cardiac arrhythmia, improves lung function, improves kidney function, and prevents one of the most frightening complications of major surgery – blood clots. I have used magnesium in my neurosurgical patients for more than 15 years and I have never had a patient develop post-operative blood clots in the legs or lungs. In most cases, the blood clot forms in the veins of the legs or pelvis – where it can suddenly enter the bloodstream, producing a fatal clot in the lungs called a pulmonary embolism. Sudden cardiac arrest can be another catastrophic event during surgery, leaving the patient with

a stroke or myocardial infarction (heart attack). Magnesium significantly protects against these complications as well. Several studies have shown that magnesium infusions can reduce the severity of a stroke or heart attack by 50%. What is important is that your tissue magnesium level be normal before surgery. An ounce of prevention is truly worth more than a pound of cure. People who take diuretics or birth control pills, or whose diet is low in fruits and vegetables, are at a very high risk of magnesium depletion. Teenagers often drink large amounts of carbonated soft drinks throughout the day. These drinks significantly lower the tissue magnesium levels. All of these individuals therefore have a higher risk of surgical complications. Magnesium is also essential for normal immune function. The bottom line is that the better your nutrition is before surgery, the less likely it is that you will have a major complication and the faster, and more completely, you will recover from surgery. Detection fallacies Over the years, I have noticed that patients who take these supplements regularly have significantly less pain and fatigue after surgery as well. PostMAR/APR 2009 • OH! 59

NUTRITION

operative fatigue has always been a problem for patients and one for which surgeons usually have little to offer. We are becoming increasingly aware of the fact that even nutrient deficiencies too small to be recognised by clinical examination can impair the body’s functioning. We call these deficiencies subclinical. A large number of people living in industrialised countries suffer from these subclinical deficiencies, and the number is continuing to grow. When doctors want to know if you have adequate amounts of a certain vitamin in your body, they usually draw your blood and have it tested for the vitamin in question. When they want to assess the adequacy of your nutrition in general, they frequently have your blood tested for your folate and vitamin B12 levels. Newer studies, however, have shown this method to be very inaccurate. In one study, doctors compared the usual blood levels of the vitamins folate, B6, and B12 to the actual levels in the tissues as measured biochemically. What they discovered was quite shocking.

60

MAR/APR 2009 • OH!

When they measured the conventional vitamin levels in a group of healthy elderly, they found that approximately 19% of the study subjects had deficiencies. Yet, when they used the more accurate biochemical method, they found that 63% of these same individuals were significantly deficient in one or more of these critical vitamins. A similar comparison of sick elderly subjects found that 60% were deficient using conventional measurement and a whopping 83% were deficient when the biochemical method was used. This study clearly demonstrates that measuring vitamin blood levels by the conventional method can result in a false assurance that all is well – when in fact, severe deficiencies may exist. This is especially true for the chronically ill. Immunity suppression It is well known that surgery and especially anaesthesia are powerful suppressors of the body’s immunity function. This is especially so for surgeries lasting longer than two hours and in cases where more than a unit of blood is lost during the procedure.

NUTRITION

This immunity suppression can last for several weeks and can be made even worse if the patient has to receive blood during or after the surgery. Immunity suppression caused by blood transfusion, especially multiple transfusions, can equal that caused by acquired immune deficiency syndrome (AIDS). A combination of poor nutrition, the trauma of surgery, blood transfusion, and anaesthesia can temporarily wipe out the immune system. It also puts you at a much higher risk of postoperative wound infection and pneumonia. It has been shown that this immune suppression caused by surgery, anaesthesia, and blood transfusion can be reversed or even prevented by proper nutrition. It will, of course, require special immunity stimulants, but it can easily be done. Cancer patients Most cancer patients have as their primary treatment the surgical removal of the tumour(s). Sometimes this can be a relatively minor procedure, as with a skin cancer. But it is often more complicated, entailing the surgical removal of the cancer and any surrounding lymph nodes. The more complicated and prolonged surgeries can be extremely stressful, both physically and psychologically. For cancer patients, not only is wound healing and avoiding all the complications associated with surgery important, but so is making sure the immune system is functioning at peak activity. The status of a person’s nutrition is critical to the immune system. Again, I emphasise that even a single nutrient deficiency can severely impair the immune system. For example, a vitamin B6 deficiency alone can lower immunity, even when the levels of all the other vitamins are perfectly normal. Of special concern are patients who undergo preoperative chemotherapy – that is, who receive a dose of chemotherapy before surgery. It is well recognised that most chemotherapy drugs cause

significant immunity suppression and interfere with wound healing, thereby significantly increasing the risk of infections after surgery. This profound level of immunity suppression can give cancer a chance to invade and spread. Several studies have shown that nutritional immune enhancement can significantly reduce complications, especially infections, following major surgeries. In one study, almost 70% of immunity-deficient cancer patients undergoing surgery developed post-operative complications as compared to 25% with functioning immune systems. This is a dramatic difference. It should be appreciated that the patients in the group with a functioning immune system did not have specific nutritional immune stimulation. My experience, as well as that of others, is that immunity not only can be restored in patients, but can also be maximised with special supplements. OH! MAR/APR 2009 • OH! 61