Ask an answerable question (PICO)：
Some patients use heating pads to relieve discomfort while staying at home. Unfortunately, heating pads can cause second-degree burns if used inappropriately. Silver sulfadiazine cream is a commonly used antibacterial agent, and has been shown to be effective against infected burn wounds. However, some patients said that the wound is prone to tingling when the cream is applied. Some patients said that they had heard of Centella Asiatica cream as causing less irritation to injuries and helping the healing process. The patients asked whether it was appropriate to use, which triggered the author's motivation to ask the same question, and explore Centella Asiatica's effects on second-degree burn wound healing.
The Method and Analysis of Literature Review：
Our study used the PICO framework for questions using different combinations of PICO elements. The keywords included Problem - Burn wounds, Burns, Burn Injury; Interventions - Centella Asiatica, Hydrocotyle, Gotu kola; Outcome - Wound healing, wound regeneration, Wound repair. The research team performed a systematic search in four different databases (Cochrane Library, PubMed, Cinahl、Embase, and Airiti Library) in December 2020. The search strategies were implemented using the Boolean logic "AND, OR, and NOT". Results of searches for years from 2011 to the present were limited. There was a total of 63 pieces of literature that matched the search criteria, after exclusion of literature review (13), unrelated topic (23), animal experiment (15), protocol (5), and duplicated papers. Two randomized controlled trials were entered for critical appraisal.
Critical Appraisal：
Assessing these two articles' effectiveness, importance, and applicability with the Critical Appraisal Skill Program tool (CASP, 2020). According to the "Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence," the reviewed articles are rated as Level 2. These two research populations were second degree burn wound patients; the intervention was to use Centella Asiatica on the wound. Muangman et al. (2016)
research shows the time of healing reduced by 1.53±0.85 days（p< .05） and length of hospital stays shortened by 1.66±1.02 days（p< .05）in the study group versus the control group. Saeidinia et al. (2017) research shows that the average time of wound complete healing was 6.8 days sooner in the study group than in the control group.
Results, Conclusions and Recommendations：
In conclusion, based on these two articles Centella Asiatica extract was effective in stimulating cellular function to increase collagen synthesis and granulation tissue in the healing process, shorten the time of re-epithelialization, wound healing, and length of hospital stays with a statistically significant difference. It is recommended that in clinical wound care, for wounds with no signs of infection, in addition to the usual use of antibacterial ointments, Centella Asiatica can be included as a reference option for wound dressing. Based on the pharmacological principles of the research, it is also possible to extend the study to the second-degree pressure wound group without signs of infection and expand the scope of the study for further verification of its effectiveness.
