OBJECTIVES: The ratio of non-fatal burns compared with fatal ones is increasing especially in high-income countries. In the management of lower leg burns, rest and elevation of affected limbs are thought to be important, but there are few guidelines for mild to moderate lower leg burns. The purpose of this study was to re-evaluate the importance of rest and elevation in the management of lower leg burns.
MATERIALS AND METHODS: We retrospectively studied 167 lower legs with second-degree or third-degree lower leg burns between October 2014 and March 2020. Age, sex, mechanism of injury, percentage of the total body surface area, treatment situation, method of treatment, wound healing period, and complications were investigated.
RESULTS: Of 167 included burns, 111 lower extremities were treated in the outpatient clinic, and 56 were treated in the hospital. Mean percentage of the total body surface area were 1.00% and 1.94%, respectively (P < .05). Seventeen cases were converted from outpatient clinic to admission treatment because of refractory wounds. Mean percentage of the total body surface area for these was larger than that for cases that received outpatient care throughout (1.62% vs 0.89%; P < .05). Patients with more than 1.0% to 1.5% total body surface area of lower leg burn were prone to have infections or have need for surgery.
CONCLUSIONS: Lower leg burns are difficult to treat because of complications. Under outpatient treatment, patients sometimes cannot rest and elevate their affected limbs because of their daily lives. Lower legs burns of >1.5% total body surface area should be treated in the hospital or with a rest level similar to admission even in the outpatient clinic.
KEY WORDS: Lower leg burn, Mild to moderate burn, Nonfatal burn
Burns, a serious and major global trauma, can include various mechanisms, types, severities, and prognoses. Both severe and lesser burns can cause morbidity, prolonged hospitalization, disfigurement, and disability.1,2
In many high-income countries, both burn sizes and burn deaths have been decreasing; most severe burns have been reported to occur in low- and middle-income countries.3-5 A decrease in burn sizes and burn deaths may be due to improvements in heating appliances, environmental arrangements, educational programs, and smoke alarms/detectors; however, the demand for treatment of nonfatal or small burns has shown a sharp increase, especially in high-income countries.
A lower leg burn is a principal influencing factor for quality of life.6 For lower leg burns, topical therapies and sometimes early surgical procedures are recommended.7 The demand for treatment of nonfatal lower leg burns within a short period and without complications is increasing.
The International Society for Burn Injuries Practice Guidelines for burn care have been written to provide clinical guidelines to improve care of burn patients, with Artz's criteria or Moylan's criteria shown to be useful for the evaluation of burn severity.8,9 However, there are no treatment guidelines for mild to moderate burns with consideration of the affected area or percentage of the total body surface area (%TBSA).
Some patients with intractable lower leg burns may improve after they are admitted to the hospital where they can receive rest and elevation of their affected limbs while in bed. That is, admission treatment or just rest of affected limbs could be an effective treatment for lower leg burns regardless of the severity. The purpose of this study was to evaluate the importance of rest and elevation in the management of lower leg burns.
MATERIALS AND METHODS
This study was a retrospective study performed at the Tokyo Medical University Hospital (TMUH), a center that accepts patients with all types of burns. All patients with lower leg burns presenting to TMUH between October 2014 and March 2020 were included. All included patients had agreed at admission to use their medical data for research by written consent. Patients with first-degree burns and moderate temperature burns were excluded because of the particular process of healing for these wounds, which made them not suitable for this study.9 Patients who dropped out during their follow-up examinations were also excluded. This study was reviewed and approved by the Institutional Review Board of Tokyo Medical University (T2019-0188).
For patients included in the study, data on age, sex, mechanism of the injury, %TBSA, depth of burn, treatment situation (admission or outpatient clinic treatment), method of treatment (conservative or surgical treatment), length of hospital stay, and wound healing duration were collected. %TBSA was calculated using the Lund and Browder chart.8,10,11 Burn depth was classified as superficial partial-thickness burn, deep partial-thickness burn, and full-thickness burn.12 These factors were assessed by the attending doctor on hospital arrival of the patient, reassessed by several physicians during patient care, and confirmed at clinical conferences, which also included board-certified burn surgeons. At TMUH, admitted patients with lower leg burns are treated with elevation of the affected limb and active rehabilitation to prevent edema or blood stasis.
The primary outcome was the duration of wound healing. Wound healing duration was defined as the number of days needed for reepithelialization. Secondary outcomes included infection rate and the need for surgical procedures like debridement or skin graft.
The study patients were divided into 2 groups: an outpatient clinic treatment group and an admission treatment group. In Japan, all people have access to hospital admission and inexpensive coverage because of Japan's universal health insurance system. However, patients who attend outpatient clinic treatment cannot quit their daily work and let their affected limbs rest and elevate inadequately. Therefore, admission treatment meant that patients were treated under a management strategy that could allow prevention of worsening of burn wounds by edema or infection, and outpatient treatment meant that patients did not have access to such management. In these 2 groups, we analyzed the primary and secondary outcomes. In addition, some subgroup analyses were performed.
Patients with lower leg burns sometimes present with exacerbation of their burn wounds in the outpatient clinic. Therefore, during outpatient clinic treatment, follow-up surveys were conducted. For patients in the outpatient clinic treatment group, patients were further divided into 2 groups: the "O-to-A group," which included patients who were treated in an outpatient clinic first but then admitted to a hospital for treatment, and the "O-to-continuation group," which included patients who started treatment in an outpatient clinic and then continued there throughout treatment. The primary and secondary outcomes in these 2 groups were analyzed. In addition, the number of patients who showed worsening of their burn wounds was also determined.
Our study also included %TBSA analyses, in which patients were stratified by %TBSA, calculated for patients in the admission group and the outpatient clinic group.
Results were assessed using F test, t test, Mann-Whitney U test, and chi-square test, as appropriate. Two-sided P ≤ .05 was considered to be statistically significant. All statistical analyses were conducted with Microsoft Excel (version 16.36) and R software (version 3.2.2.; The R Foundation for Statistical Computing).
Between October 2014 and March 2020, 303 patients presented to TMUH. Of these, 69 were excluded because of lack of follow-up results and 67 were excluded because depth or mechanism of burn was outside our study's scope. Figure 1 outlines the patients included and excluded from our study.
Among 167 patients included in this study, 74 were men (44.3%) and mean age was 39.8 ± 3.8 years (Table 1). Mean %TBSA of the admission group (1.94%) was higher than mean %TBSA of the outpatient clinic group (1.00%). Dorsum of the foot and lower thighs were the most affected area, with 69 cases and 66 cases, respectively, and the most frequent mechanism of burn injury was scald burn. With regard to the depth of burn at initial visit, 107 patients had superficial partial-thickness burns and 40 patients showed mixtures of superficial and deep partial-thickness burns; 5 patients had full thickness burns.
Among the 167 patients, 111 were treated in the outpatient clinic and 56 were admitted to the hospital at the first visit. When we compared these 2 groups, there were no significant differences in age, wound healing duration, and the infection rate. With regard to %TBSA and surgery rate, the admission group had higher numbers for both versus the outpatient clinic group.
In the follow-up surveys of the 2 outpatient clinic groups (N = 111), the O-to-A group included 17 patients. The mean %TBSA for the O-to-A group was higher than the %TBSA for the O-to-continuation group (1.62% vs 0.89%; P < .05), and the rate of surgery for the O-to-A group was higher than the rate of surgery for the O-to-continuation group (52.9% vs 1.1%; P < .05). Table 2 shows the characteristics of the patients in the outpatient clinic groups, and Figure 2 shows the results of the analysis for these patients. No significant differences were shown between these 2 groups with regard to age, wound healing duration, and infection rate. Seven patients in the O-to-A group had worsened depth of burn, and surgery was needed for 4 patients. 13 patients in the O-to-continuation group showed aggravation of injuries; however, all patients could be treated conservatively.
Analysis according to %TBSA revealed that admission rate was over 40% in the those with 1.0% or more TBSA (Table 3). For patients with more than 1.0% TBSA, wound healing duration was longer and the number of infections or surgeries was increased. For those with more than 1.5% TBSA, admission treatments were required for about 50%.
Burns follow various clinical courses, depending on the affected area, the mechanism of damage, the depth, the patient's background or past medical history, and the amount of social and medical resources. Thus, burn treatments should be flexible considering these various factors.
Few reports have discussed the epidemiology of lower leg burns. Some reports have stated that the proportion of lower extremity burn was about 30% to 40%, and the frequent mechanism of burn is scald burns,13-16 whereas other have indicated that contact burns are more common.17,18
The fundamental concept of burn treatment is to promote wound healing without the development of other complications. In general, healing that takes more than 2 or 3 weeks can result in hypertrophic scars or keloids.19 Five important factors in treatment are as follows: remove necrotic/fibrinous tissue, control edema, achieve a well-vascularized wound bed, decrease bacterial burden, and minimize/eliminate wound exudate.20 Because lower leg burns can easily lead to edema and deep vein thrombosis,7,21 the wound healing process for lower legs tends to be delayed comparing with upper extremities or other body parts. Wibbenmeyer and colleagues22 revealed that the risk of emboli in burn patients is the same as the risk shown in patients who undergo high-risk or moderate-risk surgeries, with patients with burn injuries requiring thrombo-emboli prophylaxis. Although our results showed that rest and elevation of affected limbs for edema control in those who were admitted to the hospital after injury was effective for treatment of lower leg burns, this type of treatment may increase the risk of deep vein thrombosis. Rest or elevation of affected limbs is sometimes inconsistent with prevention of deep vein thrombosis or immobilization. Therefore, appropriate management of lower leg burns with avoidance of delayed wound healing effects like edema or infection by rest or elevation of affected limbs and the prevention of concomitant complications like deep vein thrombosis or immobilization are required.
To exclude or detect the possibility of deep vein thrombosis, standardized physical examinations, like examination for edema or pain in the leg and palpable difference in temperature between the affected and unaffected limbs, are needed.22 Because it was reported that only a clinical examination may not be sufficient for diagnosis,23 a plasma D-dimer test or imaging examination (like compression ultrasonography, impedance plethysmography, and venoscan) should also be performed.22,24-27 We found that letting patients rest and elevate their affected limbs can reduce edema and could prevent deep vein thrombosis. In our hospital, wearing elastic stockings on the unaffected limb, early active rehabilitation, and, if necessary, anticoagulant medications are used to prevent deep vein thrombosis. During our study period, we had no cases of deep vein thrombosis.
Lower leg burns are prone to repetitive trauma, and the risk of Marjolin ulcer is high.21,28 Delayed wound closure due to infections or graft loss can lead to joint stiffness and contractures. Batac and colleagues29 showed that delayed admission was an independent risk factors for cellulitis. Because patients with burn wound cellulitis need prolonged hospital stays and can have more surgeries,29 it is very important to prevent infections during the treatment of burn wounds. Patients with such subsequent complications can have long-term disabilities, which can have many individual, economic, and social effects.30
Patients who are treated as outpatients sometimes cannot adequately rest and elevate their affected limbs in their daily lives. This may be a reason for edema followed by delayed wound healing or infection. Our study revealed that the number of patients with delayed wound healing, infections, and surgeries was increased in those with more than 1.0% to 1.5% TBSA. Thus, we suggest that rest and elevation may be enough to prevent edema or infection and are highly recommended for patients with more than 1.0% to 1.5% TBSA lower leg burn.
In Japan, all people can receive inexpensive medical care under the universal public insurance system; thus, we were able to provide admission treatments for our patients with relative ease. However, this is not true for all countries. In resource-limited settings, it may be difficult for patients with lower leg burns to receive admission treatment. For these cases, it may be appropriate to instruct patients on how to adequately administer edema control by themselves at home. Specifically, for example, they should be guided that to rest and elevate the affected limbs for 5 to 10 minutes every hour to improve edema of lower limbs. Of importance, the details of guidance should be concrete, clear, and easy for patients to understand. This could be a cost-effective option in resource-limited settings.
There are several limitations in our study. First, the decision of whether the patient should be treated in an outpatient clinic or in an admission situation depended on the individual clinician. The social background of patients also contributed to decisions of treatment situation. That is, some patients with severe lower leg burns might be treated in an outpatient clinic because of their personal circumstances. Second, other factors for delayed wound closure (like past medical history, medications, and nutrition) were not taken into consideration. These factors may have affected the results. Third, the definition of "rest" is quite vague. In the hospital, we can control the patient's rest level comparatively easily. However, in those who receive outpatient care, each patients could interpret the meaning of "rest" differently. It is difficult for us to describe the level of "rest" with scientific definition and define it quantitatively in this paper. Fourth, the duration of this study was about 5 years, which may be too short to evaluate long-term complications like Marjolin ulcer. Further investigations are needed to evaluate these complications.
This retrospective study evaluated patients with lower leg burns who were seen at our center between October 2014 and March 2020. Lower leg burns tend to have delayed healing; thus, we suggest that patients with 1.0% to 1.5% TBSA lower leg burns should be hospitalized or instructed in the outpatient clinic on adequate rest of their affected limbs and proper elevation to avoid ewdema or blood stasis.
Volume : 1
Issue : 3
Pages : 87 - 92
From the Department of Plastic and Reconstructive Surgery, Tokyo Medical University, Tokyo, Japan
Acknowledgements: The authors have not received any funding or grants in support of the presented research or for the preparation of this work and have no declarations of potential conflicts interest. The original research of this paper was presented at the 12th Asia Pacific Burn Congress, Singapore, August 2019, and won Best Abstract Award (Abstract 3289).
YO and MS designed this study, extracted the data, and analyzed the data. HM confirmed the data and provided critical review. All authors were involved in writing and approving the final manuscript.
Corresponding author: Yosuke Ojima, Department of Plastic and Reconstructive Surgery, Tokyo Medical University, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan
Figure 1. Flow Diagram of the Patients in the Study
Table 1. Characteristics of Patients With Lower Leg Burn Injury
Table 2. Characteristics of Outpatient Clinic Patients
Figure 2. Analysis of Patients Treated in the Outpatient Clinic
Table 3. Analysis by Total Body Surface Area