Ask an answerable question (PICO)：
A pressure injury is a common issue among bedridden patients. It will cause prolong the length of stays, increase the mortality rate, and also increase the medical cost. Wound caring and pain control are both the basic treatments for these patients. However, many clinical practice guidelines mention that the intervention of nutrition support is also quite important. If patients suffer malnutrition or are at high risk of malnutrition, the caring policies for them should include taking high calories and high protein diet treatments. Besides this, according to the research, the formula contained arginine, one kind of essential amino acid in human beings, can promote the synthesis of collagen, which can boost the healing of wounds. Based on this, the purpose of this study is to review if the arginine supplement could improve the healing of wounds sufficiently or not?
The Method and Analysis of Literature Review：
This study used the empirical method to set the PICO keyword, combines and intersects the keywords in the way of Buhlin logic AND and OR. Keywords are pressure ulcer, pressure injury, Arginine, wound healing. The database included PubMed, CINAHL, and Cochrane library, limited 2010 to 2021 and English language. There were 19 System Review (SR), and Randomized Controlled Trials (RCT) found. During the process, there were 15 articles deleted because of the incompatible topics and abstracts. After all, four articles remained included two systematic reviews and two randomized controlled trials were selected.
Critical Appraisal：
The author independently critically appraised selected studies by the following methods. First, as the two System Review articles, we used Oxford’s Systematic Review Appraisal Sheet to appraise. And the other two RCT articles, we used RCT Critical Appraisal Sheet to appraise, using the Oxford center for EBM(2010) to evaluate. Both System Review articles are level one, and the other two RCT articles are level two.
Cereda, Neyens, et al. (2017) meta-analyzed that using arginine (3 to 8.5 gram each formula), zinc, and anti-oxidant formula by oral or feeding form on those who had stage 2-4 pressure injury for two to three times a day till the eight weeks, the area of pressure injury wound decreases apparently (MD = -15.7％，95％CI-29.9~ -1.5，P = 0.03, I2 = 58.6％) and having a 40% or greater reduction in PU size (OR = 1.72, 95% CI 1.04 ~ 2.84, P = 0.033, I2 = 0%) compared to the result of the group with regular diet. Schneider & Yahia (2019) stated that supplement 4.5-9.0 grams arginine for 3-12 weeks had better healing of pressure injury wound than non-arginine formula. Wong et al. (2014) stated after 1 week of supplementation, the rate of the viable tissues in the experimental group were 71.11%, a statistically significant increase of 28.3% (95% CI, 7.5 to 49.2, p=0.007), and after 2 weeks the viable tissues increase to 43.1% from baseline (95% CI, 20.7 to 65.4, p<0.001), higher than the control group 25.93% (p=0.02).
Results, Conclusions and Recommendations：
In summary, the importance of sufficient supplements to wound healing is certain, and arginine supplements has efficacy of the pressure ulcer wound healing especially. Practically, in addition to best wound care, providing high calories and high protein diet, plus arginine formula, can better help the healing of the wound.
