Abstract:
Objective To systematically evaluate the effectiveness of epidermal growth factor (EGF) in treating patients with inhalation injury by meta analysis.
Methods Databases including PubMed, Cochrance Library, and Embase were searched using key words " inhalation injury, smoke inhalation injury, epidermal growth factor, and EGF" , and Chinese Journals Full-text Database, China Biology Medicine disc, VIP Database, and Wanfang Database were searched using key words in Chinese version "吸入性损伤,表皮生长因子" to obtain the randomized controlled trails about EGF published publicly in the treatment of patients with inhalation injury from the establishment of each database to December 2017. The measurement indexes included content of total protein and albumin, colloid osmotic pressure (COP), the number of total cells, percentages of neutrophils, lymphocytes, and fibroblasts in bronchoalveolar lavage fluid (BALF), the time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, the time of removal of tracheal tube, the amount of respiratory secretions, and the incidence of lung infection. Meta-analysis was conducted by RevMan 5.3 statistical software.
Results A total of 6 trials involving 375 patients were included, with 182 patients in group EGF who received EGF treatment and 173 patients in conventional treatment group who received conventional treatment. All of the 6 trails had unclear risk of bias. The content of total protein and albumin and COP in BALF of patients in group EGF were lower than those in conventional treatment group, with standardized mean differences (SMDs) respectively -9.37, -26.77 , and -8.13 [with 95% confidence intervals (CIs) respectively -14.11--4.63, -41.85--11.69, -9.54--6.73,
P<0.001]. The number of total cells and percentages of neutrophils and lymphocytes in BALF of patients in group EGF were lower than those in conventional treatment group, while the percentage of fibroblasts in BALF of patients in group EGF was higher than that in conventional treatment group, with SMDs respectively -20.22, -13.08, -12.28, 2.99 (with 95% CIs respectively -22.27--17.66 , -14.76--11.40, -13.86--10.70, 2.48-3.50,
P<0.001). The time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, and the time of removal of tracheal tube of patients in group EGF were shorter than those in conventional treatment group, with SMDs respectively -1.05, -1.22 , -1.11 (with 95% CIs respectively -1.36--0.74, -1.54--0.91, -1.39--0.82,
P<0.001). The amount of respiratory secretions of patients in group EGF was lower than that in conventional treatment group, with SMD -1.44 (with 95% CI -1.90--0.98,
P<0.001). The incidence rate of pulmonary infection of patients in group EGF was lower than that in conventional treatment group, with relative risk 0.46 (with 95% CI 0.24-0.89,
P<0.05). There may be publication bias in the content of total protein, albumin, and COP in BALF (
P<0.05), while the time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, and the time of removal of tracheal tube showed no significant publication bias (
P>0.05).
Conclusions Conventional treatment combined with EGF therapy can reduce respiratory inflammation of inhalation injury, promote restoration of respiratory epithelium, shorten the time of removal of tracheal tube, reduce the incidence of pulmonary infection of patients, and therefore has good effect on inhalation injury.