Amniotic Membrane Dressing Versus Nitrofurazone-impregnated Dressing in the Treatment of Second-degree Burn Wounds

A Randomized Clinical Trial

Jafar Kazemzadeh, MD; Awat Yousefiazar, MSc; Afshin Zahedi, MD


Wounds. 2021;33(8) 

In This Article

Materials and Methods

Study Design

This research was conducted as a single-center RCT at the Trauma and Burn Center of Imam Khomeini Hospital in Urmia, Iran. The study was conducted with the approval of the Institutional Review Board in accordance with the Declaration of Helsinki as well as the Ethics Committee of the university with ethics code IR UMSU.REC.139.245, which was registered according to the Registry of Clinical Trials in the Iranian Registry of Clinical Trials with the Registration number IRCT20181216041996N1.

Nitrofurazone 0.2% as a water-soluble ointment was selected as the comparator to amniotic membrane because it is the most commonly used product available in the authors' pharmaceutical market. An amniotic membrane (ITP Amniotic Membrane; Iranian Tissue Product Co.) in sterilized packaging was used to prevent transmission of infection.

Inclusion and Exclusion Criteria

Inclusion criteria stipulated study participants must have had a second-degree burn (TBSA < 10%) and could be of any age. Patients were eligible for inclusion if they were referred during hospitalization and did not require debridement in an operating room. Patients were excluded if they had any chronic conditions or comorbidities or if they had a history of smoking, drug, or psychotropic substance misuse or addiction. Burns on the face and/or genitalia and infected burns upon referral were excluded. Importantly, those with previous reaction and hypersensitivity to nitrofurazone ointment and/or to amniotic membrane dressings were not eligible for inclusion.


For randomization, the sequences were assigned by an independent researcher using Random Allocation Software version 1.0 (Informer Technologies, Inc) in permuted blocks of 2 or 4. Of the patients meeting the accepted inclusion criteria, 2 patients declined to participate and 1 patient was discharged. The remaining patients hospitalized in the burn ward due to second-degree burns provided written consent and were enrolled. At the time of randomization, a nurse who was not involved in the study process or care of patients opened a numbered envelope containing patient allocation sheets and the patient was assigned to one of the 2 study groups.

Sample Size

Calculation of the number of samples was based on a previous study[21] and the variable of epithelialization rate of second-degree burn.

Statistical parameters for calculation of sample size were α = 0.05, β = 0.2, Z1 = 1.961150826, Z2 = 0.841623031, μ1 = 14.2, μ2 = 13.3, SD1 = 0.96, SD2 = 0.95, and n = 18.

The authors' calculations yielded an estimate of at least 18 subjects per group. In order to prevent attrition in the sample, at the beginning of the study a sample size of 35 subjects was selected as the total final sample size for each group.

Care Protocol

The second-degree burns were dressed either using the amniotic membrane or nitrofurazone-impregnated gauze, which were matched based on TBSA and wound depth. In the first group, the amniotic membrane products, which were purchased by the authors' hospital, were applied and covered with 2 separate layers of gauze. The first layer was petroleum-impregnated gauze, and the second layer was wet gauze moistened by saline. Participants in the nitrofurazone-impregnated gauze group were provided 20 g of the ointment per TBSA under the gauze, which was covered by a layer of dry gauze. In the nitrofurazone group, dressing changes occurred once daily and in the amniotic membrane group dressing changes occurred once a week. For pain management, morphine sulfate was the only medication used in the study groups.

Data Collection

Demographic (sex, age, clinical pain severity assessed using a visual analog scale [VAS], dressing change frequency, epithelialization rate, length of hospitalization, morphine intake, and scarring) information was assessed using the Vancouver Scar Scale [VSS] and were collected with a pen and paper checklist for all patients, where questions were range based. While in the hospital, assessment was performed on days 1, 7, 14, and 30 and continued after discharge from the hospital. Post-discharge, the variables were assessed during patient visits in the outpatient burn clinic on days 7, 14, and 30.

Study data were collected by the researcher via observation, interview, examination of the patient, and completion of the checklist and were documented into medical charts by the same researcher. Pain severity was documented on a numeric pain distress scale; individual charts on which the patients could mark their level of pain were used. The rate of wound healing (epithelialization) was evaluated by observation. Scarring was evaluated using the VSS; this tool comprises 4 subscales: pigmentation, 0–2; vascularity, 0–3; pliability, 0–5; and height, 0–3. Subscale scores then were summed for a total score of 0 to 13. Visual and direct examination also were employed. During dressing changes, data collection was done by the researcher based on observation and scales using the checklist.

Statistical Analysis

The collected data were analyzed by a statistics expert using SPSS software, version 17 (IBM Corporation). Quantitative and qualitative variables were reported as mean ± standard deviation and percentage (frequency) in the form of statistically standard tables, respectively. To analyze the quantitative variables between the 2 groups, an independent t-test (and if necessary, Mann-Whitney) was used; chi-squared tests were employed to compare the frequency. Wherever chi-square conditions were not met, the authors used its alternative, the Fisher exact test; P <.05 was considered significant.