Evaluation On Intravenous Lidocaine For Treatment Of Difficult-to-treat Asthma

Background and ObjectivesThe morbidity of bronchial asthma has been increasing in recent years.5%-10%of branchial asthma cases who have got difficulty in control when treated with regularmethods are described as difficult-to-treat asthma (DTA). Possible mechanisms ofDTA include resistance to corticosteroids, abnormal immunoreactions andmodulation, airway remodeling and infections. Lidocaine, a traditional localanesthetic is supposed to reduce bronchial hyperreactivity through local nerveblocking, and inhibit local airway inflammation by functioning at immunologicalcells, showing potentials in treatment of bronchial asthma, especially DTA. Assuggested by related researches, lidocaine is a safe medication for bronchial asthmawhich can improve asthma control and reduce the dosage of systemic corticosteroids.However, more clinical evidences are needed to support the efficacy and safety oflidocaine in treatment of DTA. Here we evaluate intravenous lidocaine therapy forDTA through a double-blind, randomized and placebo-controlled clinical trial, thusproviding evidence for rational administration.MethodsVolunteers were consecutively recruited from DTA resident patients inDepartment of Respiratory and Critical Care Medicine, the First Affiliated Hospital ofZhengzhou University from October2012to August2013. Diagnosis of DTA wasbased on the latest experts consensus published by Chinese Medical Association. Patients involved were randomly divided into lidocaine-treating group andplacebo-control group. All the patients were treated with standard protocal accordingto GINA2011which included intentional care, necessary psychological interventionand united medication. Besides previously mentioned methods, volunteers inlidocaine-treating group were given2%lidocaine through intravenous injection whilecontrol group were given normal saline as placebo.6-month follow-up was carriedout to further evaluate asthma control. Results were collected in double-blind way.Duration of hospital stays, dosage of systemic corticosteroids, levels of asthmacontrol and ACT scoring in follow-up period and needs of oral corticosteroids wereall recorded and analyzed.Statistical analysis were done with SPSS version19.0. Quantitative data,including duration of hospital stays, dosage of systemic corticosteroids and ACTscoring were compared by t-test or non parameter test. Categorical variables, such asgender, age and levels of asthma control, were compared by chi-square test orcorrected chi-square test. Analysis of correlation between quantitative data andcategorical variables were carried out by Spearman correlation coefficient method.Results65DTA patients were involved in this study, in which61finished the test,including28male cases (45.9%) and33female cases (54.1%), with age rangingfrom34to67(average52.36±7.66). Gender and age composition in lidocaine-treating group (29cases) were of no significant difference with placebo-control group.Compared with control group, cases in lidocaine-treating group showed a decrease induration of hospital stays (9.00±1.909days versus12.34±1.771days) and thedosage of intravenous corticosteroids (772.41±279.20mg versus1210.63±185.40mg). During first2months after discharged, lidocaine group showedsignificant improvements in levels of asthma control and ACT scoring (23.83±1.71versus20.78±3.11in1stmonth and24.14±1.64versus21.44±3.16in2ndmonth).The two groups also had differences in requirements of oral corticosteroids anddependence on medical care. ConclusionIntravenous lidocaine can reduce the duration of hospital stays and dosage ofsystemic corticosteroids in DTA patients. With significant improvement of asthmacontrol and minor adverse effects, intravenous lidocaine can be adopted as aneffective and safe choice for DTA treatment.