Effectiveness of glutamine and arginine in wound healing of pressure ulcers: A systematic review protocol

INTRODUCTION

Various nutrients play a physiological role in the healing process of pressure ulcers (PUs). Nutritional interventions include the administration of enteral nutritional supplements and formulas containing arginine, glutamine, and micronutrients. The aim of this systematic review is to evaluate the effectiveness of enteral nutritional supplements and formulas containing arginine and glutamine on wound-related outcomes. These include (1) time to healing, (2) changes in wound size, (3) local wound infection, (4) PU recurrence, and (5) PU-related pain.

MATERIALS AND METHODS

This protocol was developed according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). A search will be conducted in the Cochrane Library, EMBASE, PubMed (MEDLINE), CINAHL (EBSCOhost interface) and Web of Science. In addition, a manual search will be conducted to identify relevant records. Except for systematic reviews, no restrictions will be placed on the study design, the population studied or the setting. Studies that do not address PUs, in vitro studies and studies that do not report wound-related outcomes will be excluded. Study selection, risk of bias assessment and data extraction will be performed independently by three researchers. Depending on the extent of heterogeneity of interventions, follow-up time and populations, results will be summarised either by meta-analysis or narrative synthesis.

CONCLUSIONS

This is the first systematic review to identify, evaluate and summarise the current evidence for enteral arginine and glutamine supplementation on wound-related outcomes in PUs. The review will provide a solid basis for deriving valid and clinically relevant conclusions in this area.

Nutritional interventions for preventing and treating pressure ulcers

BACKGROUND

Pressure ulcers are localized injuries to the skin or the underlying tissue, or both, and are common in older and immobile people, people with diabetes, vascular disease, or malnutrition, as well as those who require intensive or palliative care. People with pressure ulcers often suffer from severe pain and exhibit social avoidance behaviours. The prevention and treatment of pressure ulcers involves strategies to optimize hydration, circulation, and nutrition. Adequate nutrient intake can reduce the risk factor of malnutrition and promote wound healing in existing pressure ulcers. However, it is unclear which nutrients help prevent and treat pressure ulcers. This is an update of an earlier Cochrane Review.

OBJECTIVES

To evaluate the benefits and harms of nutritional interventions (special diets, supplements) for preventing and treating pressure ulcers in people with or without existing pressure ulcers compared to standard diet or other nutritional interventions.

SEARCH METHODS

We used extensive Cochrane search methods. The latest search was in May 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in people with or without existing pressure ulcers, that compared nutritional interventions aimed at preventing or treating pressure ulcers with standard diet or other types of nutritional interventions.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcome for prevention studies was the proportion of participants who developed new (incident) pressure ulcers. For treatment studies, our primary outcomes were time to complete pressure ulcer healing, number of people with healed pressure ulcers, size and depth of pressure ulcers, and rate of pressure ulcer healing. Secondary outcomes were side effects, costs, health-related quality of life and acceptability. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We included 33 RCTs with 7920 participants. Data for meta-analysis were available from 6993 participants. Pressure ulcer prevention Eleven studies (with 12 arms) compared six types of nutritional interventions for the prevention of pressure ulcers. Compared to standard diet, energy, protein and micronutrient supplements may result in little to no difference in the proportion of participants developing a pressure ulcer (energy, protein and micronutrient supplements 248 per 1000, standard diet 269 per 1000; RR 0.92, 95% CI 0.71 to 1.19; 3 studies, 1634 participants; low-certainty evidence). Compared to standard diet, protein supplements may result in little to no difference in pressure ulcer incidence (protein 21 per 1000, standard diet 28 per 1000; RR 0.75, 95% CI 0.49 to 1.14; 4 studies, 4264 participants; low-certainty evidence). The evidence is very uncertain about the gastrointestinal side effects of these supplements (protein 109 per 1000, standard diet 155 per 1000; RR 0.70, 95% CI 0.06 to 7.96; 2 studies, 140 participants, very low-certainty evidence). The evidence is very uncertain about the effects of protein, arginine, zinc and antioxidants; L-carnitine, L-leucine, calcium, magnesium and vitamin D; EPA, GLA and antioxidants; disease-specific supplements on pressure ulcer incidence when compared to standard diet (1 study each; very low-certainty evidence for all comparisons). Pressure ulcer treatment Twenty-four studies (with 27 arms) compared 10 types of nutritional interventions or supplements for treatment of pressure ulcers. Compared to standard diet, energy, protein and micronutrient supplements may slightly increase the number of healed pressure ulcers (energy, protein and micronutrients 366 per 1000, standard diet 253 per 1000; RR 1.45, 95% CI 1.14 to 1.85; 3 studies, 577 participants, low-certainty evidence). The evidence is very uncertain about the effect of these supplements on gastrointestinal side effects. Compared to standard diet, the evidence is very uncertain about the effect of protein, arginine, zinc and antioxidant supplements on pressure ulcer healing (pressure ulcer area: mean difference (MD) 2 cm² smaller, 95% CI 4.54 smaller to 0.53 larger; 2 studies, 71 participants, very low-certainty evidence). The evidence on side effects of these supplements is very uncertain. Compared to standard diet, supplements with arginine and micronutrients may not increase the number of healed pressure ulcers, but the evidence suggests a slight reduction in pressure ulcer area (MD 15.8% lower, 95% CI 25.11 lower to 6.48 lower; 2 studies, 231 participants, low-certainty evidence). The evidence is very uncertain about changes in pressure ulcer scores, acceptability, and side effects of these supplements. Compared to placebo, collagen supplements probably improve the mean change in pressure ulcer area (MD 1.81 cm² smaller, 95% CI 3.36 smaller to 0.26 smaller; 1 study, 74 participants, moderate-certainty evidence). The evidence is very uncertain about the effect of these supplements on side effects. The evidence is very uncertain about the effects of vitamin C, different doses of arginine; EPA, GLA (special dietary fatty acids) and antioxidants; protein; a specialized amino acid mixture; ornithine alpha-ketoglutarate and zinc supplements on pressure ulcer healing (1 or 2 studies each; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The benefits of nutritional interventions with various compositions for pressure ulcer prevention and treatment are uncertain. There may be little or no difference compared to standard nutrition or placebo. Nutritional supplements may not increase gastrointestinal side effects, but the evidence is very uncertain. Larger studies with similar nutrient compositions would reduce these uncertainties. No study investigated the effects of special diets (e.g. protein-enriched diet, vegetarian diet) on pressure ulcer incidence and healing.

The Clinical and Cost-Effectiveness of an Individualized Nutritional CAre (INCA) Bundle versus Standard Care for Adults with Pressure Injuries Receiving Home Nursing Services: A Protocol for a Cluster Randomized and Pragmatic Clinical Trial with an Economic Evaluation

BACKGROUND

Pressure injuries (PIs) represent a significant healthcare challenge in Singapore among the aging population. These injuries contribute to increased morbidity, mortality, and healthcare expenditure. Existing research predominantly explores single-component interventions in hospital environments, often yielding limited success. The INCA Trial aims to address this research gap by conducting a comprehensive, cluster randomized controlled trial that integrates education, individualized nutritional support, and community nursing care. This study is designed to evaluate clinical and cost-effectiveness outcomes, focusing on PI wound area reduction and incremental costs associated with the intervention.

METHODS

The INCA Trial employs a two-group, non-blinded, cluster randomized, and pragmatic clinical trial design, recruiting 380 adult individuals (age ≥ 21 years) living in the community with stage II, III, IV, and unstageable PI(s) who are receiving home nursing service in Singapore. Cluster randomization is stratified by postal codes to minimize treatment contamination. The intervention arm will receive an individualized nutrition and nursing care bundle (dietary education with nutritional supplementation), while the control arm will receive standard care. The 90-day intervention will be followed by outcome assessments extending over one year. Primary outcomes include changes in PI wound area and the proportion of participants achieving a ≥40% area reduction. Secondary outcomes include health-related quality of life (HRQOL), nutritional status, and hospitalization rates. Data analysis will be conducted on an intention-to-treat (ITT) basis, supplemented by interim analyses for efficacy and futility and pre-specified sensitivity and subgroup analyses. The primary outcome for the cost-effectiveness analysis will be based on the change to total costs compared to the change to health benefits, as measured by quality-adjusted life years (QALYs).

DISCUSSION

The INCA Trial serves as a pioneering effort in its approach to PI management in community settings. This study uniquely emphasizes both clinical and economic outcomes and melds education, intensive dietetic support, and community nursing care for a holistic approach to enhancing PI management.

Effect of supplements/intensive nutrition on pressure ulcer healing: a multicentre, randomised controlled study

OBJECTIVE

To investigate the effectiveness of an intensive nutrition intervention or use of wound healing supplements compared with standard nutritional care in pressure ulcer (PU) healing in hospitalised patients.

METHOD

Adult patients with a Stage II or greater PU and predicted length of stay (LOS) of at least seven days were eligible for inclusion in this pragmatic, multicentre, randomised controlled trial (RCT). Patients with a PU were randomised to receive either: standard nutritional care (n=46); intensive nutritional care delivered by a dietitian (n=42); or standard care plus provision of a wound healing nutritional formula (n=43). Relevant nutritional and PU parameters were collected at baseline and then weekly or until discharge.

RESULTS

Of the 546 patients screened, 131 were included in the study. Participant mean age was 66.1±16.9 years, 75 (57.2%) were male and 50 (38.5%) were malnourished at recruitment. Median length of stay was 14 (IQR: 7-25) days and 62 (46.7%) had ≥2 PUs at the time of recruitment. Median change from baseline to day 14 in PU area was -0.75cm² (IQR: -2.9_-0.03) and mean overall change in Pressure Ulcer Scale for Healing (PUSH) score was -2.9 (SD 3.2). Being in the nutrition intervention group was not a predictor of change in PUSH score, when adjusted for PU stage or location on recruitment (p=0.28); it was not a predictor of PU area at day 14, when adjusted for PU stage or area on recruitment (p=0.89) or PU stage and PUSH score on recruitment (p=0.91), nor a predictor of time to heal.

CONCLUSION

This study failed to confirm a significant positive impact on PU healing of use of an intensive nutrition intervention or wound healing supplements in hospitalised patients. Further research that focuses on practical mechanisms to meet protein and energy requirements is needed to guide practice.

Side Effects of Amino Acid Supplements

The aim of the article is to examine side effects of increased dietary intake of amino acids, which are commonly used as a dietary supplement. In addition to toxicity, mutagenicity and carcinogenicity, attention is focused on renal and gastrointestinal tract functions, ammonia production, and consequences of a competition with other amino acids for a carrier at the cell membranes and enzymes responsible for their degradation. In alphabetic order are examined arginine, β-alanine, branched-chain amino acids, carnosine, citrulline, creatine, glutamine, histidine, β-hydroxy-β-methylbutyrate, leucine, and tryptophan. In the article is shown that enhanced intake of most amino acid supplements may not be risk-free and can cause a number of detrimental side effects. Further research is necessary to elucidate effects of high doses and long-term consumption of amino acid supplements on immune system, brain function, muscle protein balance, synthesis of toxic metabolites, and tumor growth and examine their suitability under certain circumstances. These include elderly, childhood, pregnancy, nursing a baby, and medical condition, such as diabetes and liver disease. Studies are also needed to examine adaptive response to a long-term intake of any substance and consequences of discontinuation of supplementation.

The use of oral and enteral tube-fed arginine supplementation in pressure injury care: A systematic review and meta-analysis

AIM

Pressure injuries (PIs) are one of the most common complications related to immobility, especially in hospitalized patients, which lead to increased morbidity, infection and overall decreased quality of life. Arginine supplementation may prevent the development of PIs. This study has summarized the findings of studies on the effect of arginine supplementation on PI healing.

DESIGN

Systematic review and meta-analysis.

METHODS

This study was conducted on online electronic databases including PubMed, Scopus, Web of Science, Google Scholar and Embase to identify relevant clinical trial studies up to September 2020. The pooled effect size of arginine supplement effects on PI was evaluated with standard mean difference (SMD) with 95% confidence interval (CI).

RESULTS

Eight studies met the inclusion criteria for this meta-analysis with 196 patients. PIs were significantly improved with Arginine supplementation (SMD: -0.6; CI 95%: -0.9 to -0.3, I² : 72.5%, p = .001). Subgroup analysis showed that administering Arginine supplement more than 15 g/day had more beneficial effects on the healing of PIs (SMD: -2.8; CI 95%: -4.08 to -1.52, I² : 54.7%, p = .138).

CONCLUSIONS

Our findings suggest that the administration of Arginine supplement in patients with PIs can accelerate the healing of this type of ulcer. Arginine is a supplement, and primary treatment is still needed to optimize PI healing. Therefore, arginine supplementation in addition to primary treatment seems to be an appropriate approach for the healing of PIs. Further well-designed studies are necessary to prevent the development of PIs compared to their primary treatment.

COVID-19 related pressure injuries in patients and personnel: A systematic review

BACKGROUND

Coronavirus disease 2019 (COVID-19) is causing a rapid and tragic health emergency worldwide. Because of the particularity of COVID-19, people are at a high risk of pressure injuries during the prevention and treatment process of COVID-19.

OBJECTIVES

This systematic review aimed to summarize the pressure injuries caused by COVID-19 and the corresponding preventive measures and treatments.

METHODS

This systematic review was according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. PubMed, Web of science and CNKI (Chinese) were searched for studies on pressure injuries caused by COVID-19 published up to August 4, 2020. The quality of included studies was assessed by the Newcastle-Ottawa Quality Assessment Scale (NOS) and the CARE guidelines.

RESULTS

The data were extracted from 16 studies involving 7,696 participants in 7 countries. All studies were published in 2020. There are two main types of pressure injuries caused by the COVID-19: 1) Pressure injuries that caused by protective equipment (masks, goggles and face shield, etc.) in the prevention process; 2) pressure injuries caused by prolonged prone position in the therapy process.

CONCLUSIONS

In this systematic review, the included studies showed that wearing protective equipment for a long time and long-term prone positioning with mechanical ventilation will cause pressure injuries in the oppressed area. Foam dressing may need to be prioritized in the prevention of medical device related pressure injuries. The prevention of pressure injuries should be our particular attention in the course of clinical treatment and nursing.

Protein Considerations for Athletes With a Spinal Cord Injury

Athlete participation in the Paralympic games is steadily increasing; prompting research focused on the unique needs of this population. While the Paralympic Games includes a diversity of athletes, athletes with a spinal cord injury (PARA-SCI) represent a subgroup that requires specialized recommendations. Nutritional guidelines designed to optimize performance, in the context of the neurological impairments, are required. This narrative review summarizes the current literature regarding the importance of dietary protein for optimal health and performance. Factors with the potential to affect protein needs in PARA-SCI including loss of active muscle mass, reduced energy expenditure, and secondary complications are examined in detail. Furthermore, we analyze protein intakes in PARA-SCI from the available research to provide context around current practices and trends. In conclusion, we make the case that protein recommendations for able-bodied athletes may not be directly transferable to PARA-SCI. Consequently, PARA-SCI need their own guidelines to maximize performance and ensure long-term health.

An improvement in acute wound healing in rats by the synergistic effect of photobiomodulation and arginine

In this probe, at first we examined the best route and dosage of arginine administration on wound healing in an excisional wound model in rats. Next, we intend to assess the impact of photobiomodulation (PBM) and arginine, individually and together, on the wound healing. In the pilot study, an excisional wound was made in each of 24 rats. There were 4 groups. Group 1 was the control group. In groups 2 and 3, wounds were topically treated with arginine ointments (ARG.) 2% and 5%, respectively. In group 4, arginine was injected (ARG. INJ.,i.p.). In the main phase, in 24 new rats, an excisional wound was made. There were 4 groups: group 5 served as the control. Wounds in group 6 were topically treated with ARG 2%. Wounds in group 7 were subjected to PBM. Wounds in group 8 were treated with PBM+ARG. 2%. On day 15, wound area measurement, wound strength, and stereological examination were performed. In the pilot study, we found that the ARG 2% ointment significantly decreased wound area than ARG. 5%, ARG. INJ. and control groups, and significantly increased wound strength compared to the control and ARG.5% groups. In the main phase, a significant decrease of wound area in all treatment regimens was induced. PBM + ARG. 2% and PBM treatment regimens significantly improved wound strength and almost all stereological parameters, compared to the control and ARG. 2% groups. PBM + ARG. 2% induced anti-inflammatory and angiogenic activities, and hastened the wound healing process in an excisional wound model in rats.

Nutritional therapy in the treatment of pressure injuries: a systematic review

Abstract Objective: to review literature on the use of nutritional therapy in the treatment of pressure injuries. Methods: a systematic review of the PubMed, Lilacs and Scielo databases was performed, with studies in the English and Portuguese languages published in the last five years selected. Result: three articles that investigated the use of different doses of arginine, a mixture of amino acids and nutritional supplements enriched with arginine, zinc and antioxidants were analyzed. The studies found that there was a reduction in the area of wounds in the intervention groups, although the difference in size was not significant in all the articles. Conclusion: nutritional intervention should be considered an integral part of the treatment of pressure injuries. The use of certain nutrients may positively affect the healing process of such injuries. Due to the heterogeneity of the methodologies used, the small sample size and the range of intervention times and nutrients used, more scientifically rigorous studies are recommended to create an evidence based nutritional intervention model for the treatment of pressure injuries.