Nutr in Wounds

Learning Objectives
Upon completion of this Journal Club the participant will be able to:

Describe how malnutrition can impair wound healing.
List at least two changes in nutritional needs during wound healing.
Describe at least one special consideration for nutritional needs during wound healing in diabetic patients.

Background Information

Wounds fall into four categories, including surgical, trauma, burns, and chronic. While surgical wounds are expected to increase over the next four to five years, the severity and size will likely decrease due to improving and minimally invasive surgical techniques. There are an estimated 1.5 million traumatic wounds yearly and around 3.3 million burns that require some level of outpatient medical attention. Each year, bout 6.3 million burns require more advanced treatment. Chronic wounds take longer to heal. About 7.4 million pressure ulcers, 11 million venous ulcers, and 11.3 million diabetic ulcers require treatment each year. These types of wounds are more common in elderly patients and are expected to increase by about 40% along with the aging population.

Health care and other costs associated with chronic wounds are estimated at $20-$25 billion per year. Acute and trauma wounds cost an additional $7-10 billion each year

•Nutritional interactions:

–Wounds cause acute phase reaction:

•Hypermetabolic, catabolic

•Increased energy and protein needs

•Reduced anabolic hormones and hyperglycemia

•

–Wounds increase energy and protein needs:

•According to severity of wound

•Direct influence of existing nutritional status and
dietary intake

When any significant wound occurs, the body reacts with hypermetabolism and catabolism. During this time, the body will break down its own protein tissues to provide the materials and mediators needed to heal. If the body has adequate protein stores, it will prioritize wound healing over other body processes to quickly shore up the problem. The body works to make protein building blocks, or amino acids, available for wound healing at the expense of more general health maintenance.

Both catabolism and anabolism kick into high gear with a significant wound. Catabolism efforts provide the protein, initiates the healing process, and orchestrates the activities required to successfully and quickly heal a wound. Anabolism builds the materials required in wound healing. So, while the body is breaking down tissues to feed the process, it is also building tissues to make it happen.

In addition, anabolic hormones tend to be depressed during the acute phase response. This includes sex hormones, growth hormone, and insulin. Blood sugars tend to rise and the combination of acute phase reactions make it challenging to maintain a controlled blood glucose level in patients with diabetes.

Energy and protein needs are increased according to the severity of the wound. There is also an increase in a number of other specific nutrients that are required to initiate and fully heal wounds. The body uses its existing pool of nutrients that must be replenished to continue this work. If the body starts out in a malnourished state, it is very likely that both rate and quality of healing will be impeded. Thus, the rate and quality of healing depends on the adequate flow of nutrients that are needed for the healing process to occur.

We will be talking about nutrition from two perspectives: what the body has as nutritional stores and what the body needs in nutrient intake.

Baseline Body Composition Matters

•What the body has:

–Water (70%)

–Protein (20%)

•Muscle – 60%

•Visceral tissues – 20%

•Connective tissues – 15%

•Other proteins – 5%

–Minerals (10%)

–Fat tissues (25%)

First it will be valuable to see what a “reference” body has to offer in the way of nutrients. Body tissues can be categorized as lean or fat tissue. The lean compartment contains most of the metabolically active tissue, including protein stores of muscle and organ tissues. Other lean tissues include water, bone, and collagen. The lean compartment holds about 40,000 calories worth of energy and is most closely related to the ability of the body to survive. Fat tissues expand and contract according to the balance of calorie intake and calorie demand. These tissues are much less metabolically active and really considered a storage of energy, in terms of nutrient value, holding around 150,000 calories.

If starvation occurs, the body will preserve lean tissues as long as possible and use up fat to provide needed energy. About two-thirds of what the body loses during starvation, which you may also know as “dieting”, is fat tissue. This is different when a wound or even an infection occurs. The body breaks down protein tissues at a rate that is dependent on the severity of the infection or wound. The body weight lost during this kind of calorie imbalance is about 80-90% lean tissue. While it is purposeful for a healing process, it can be detrimental if a balance of energy and protein is not maintained through dietary intake.

http://mediligence.com/blog/2008/05/08/wound-prevalence/