Clinicians continue to question if oral or tube feedings formulated with arginine hasten wound healing time versus standard high calorie, high protein supplements. There is an increase in the number of studies that examine the role of arginine in combination with other nutrients to facilitate pressure injury healing. Many of the studies were conducted in Europe or Australia using products that are not always marketed in the United States. However, very similar products are available.

Arginine as a Conditionally Indispensable Amino Acid

There are nine indispensable (essential) amino acids that our bodies require to meet our daily nutritional needs. Three amino acids—arginine, glutamine and cysteine—are considered conditionally indispensible amino acids because they become essential due to trauma, stress, chronic disease or poor dietary intake. L-Arginine is 32% nitrogen and has several functions including accelerating insulin secretion, stimulating protein regeneration and promoting the transport of amino acids into the cells. Arginine is a donor to nitric oxide, which increases blood flow and oxygen to the wound, thus increasing collagen formation and reducing inflammation.

What the Studies Say About Arginine and Wound Healing

The Cereda et al. small study in 2009 included daily offering of an additional 400mL high calorie nutritional supplement containing 500cal, 34g of protein, 18mg of zinc, 6g of arginine, and 500mL of ascorbic acid.¹ After eight weeks, the researchers concluded healing of stage 2 or higher pressure injuries in older adults was accelerated with the addition of the specialized supplement. Using the same formula in an randomized controlled trial (RCT), van Anholt et al. studied the result on non-malnourished patients with stage 3 and 4 pressure injuries.² This 8-week study also saw a reduction in pressure injury size for those drinking the special supplement versus those consuming the placebo. Due to the shorter healing rate, there was a decrease in nursing time spent changing dressings, which is a cost effective benefit. A multi-center RCT study in long- term care and home care included 200 malnourished patients with stage 2 - 4 pressure injuries.³

All of the patients received 2 bottles per day (400mL) of an energy-dense, protein-rich oral formula providing 500kcal and 40g of protein for 8 weeks. However, the formula for those in the experimental group also contained 6g of arginine, 500mg. of ascorbic acid, 18g of zinc and added copper. 69.9% of those in the experimental group had a 40% or greater reduction in pressure injury size in 8 weeks compared to 54.1% in the control formula group. The conclusion was for malnourished patients with pressure injuries receiving nutritional support and guideline-based wound care management, the use of a nutritional formula enriched with arginine, zinc, and antioxidants offered an additional benefit to wound healing. Based on the studies of arginine, there is moderate quality evidence supporting the positive effect of offering a high calorie, high protein nutritional supplement containing arginine and micronutrients to promote pressure injury healing.

The positive effect of the arginine supplements is probably due to the synergistic effect of the combination of nutrients since research offering just arginine alone has not been effective.

References:

1. Cereda, E., A. Gini, C. Pedrolli, et al. (2009). "Disease-specific, versus standard, nutritional support for the treatment of pressure ulcers in institutionalized older adults: a randomized controlled trial." Journal of the American Geriatrics Society 57(8): 1395-1402.

2. van Anholt RD, Sobotka L, Meijer EP, Heyman H, Groen HW, Topinková E, van Leen M, Schols JMGA. Specific nutritional support accelerates pressure ulcer healing and reduces wound care intensity in non-malnourished patients. Nutrition. 2010 Sep; 26(9): 867-872.

3. Cereda E, er al.; for the Oligo Element Sore Trial Study Group. A Nutritional Formula Enriched with Arginine, Zinc, and Antioxidants for the Healing of Pressure Ulcers: a Randomized, Controlled Trial. Ann Intern Med 2015; 162(3): 167-717

About The Author

Mary Ellen Posthauer RDN, CD, LD, FAND is an award winning dietitian, consultant for MEP Healthcare Dietary Services, published author, and member of the Purdue University Hall of Fame, Department of Foods and Nutrition, having held positions on numerous boards and panels including the National Pressure Ulcer Advisory Panel and the American Dietetic Association's Unintentional Weight Loss work group.