2. Materials and Methods
2.1 Inclusion and exclusion criteria
We screened a total of 378children (6–12 years-of-age) with M. pneumoniae pneumonia who had been hospitalized at Beijing Friendship Hospital affiliated toCapital Medical University between February 2017 and December 2018.Of these, 130 were not eligible, as determined by our inclusion criteria, and 91 declined to take part. Consequently, our final analysis featured 157 children; these children were randomly allocated into a control group (82 patients) and an HFCWO group (75 patients).
The inclusion criteria were as follows:1) clinical manifestations of pneumonia, such as fever and cough;2) radiological changes associated with pneumonia; 3) an antibody titer ≥1:160 in the gelatin particle agglutination assay;4) no treatment prior to admission; and 5) no requirement for immediate oxygen therapy. Patients were excluded if pathogen detection tests suggested that the patient had a combination of infections, if chest radiography showed obvious pulmonary consolidation, if the patient suffered from congenital respiratory problems, or if the patient was unable to complete the lung function test.
The study was approved by the medical ethics committee of Beijing Friendship Hospital affiliated toCapital Medical University (Reference Number: 2017-239) and the parents/guardians of all included subjects provided informed and signed consent.
2.2 Treatment
The control group were administered with azithromycin (Pfizer Ireland Pharmaceuticals, NY, USA) via an intravenous drip (10 mg/kg, once daily),Budesonide Suspension for Inhalation (AstraZeneca Pty Ltd., North Ryde, Australia) by atomization inhalation (2 mg, twice daily), and Compound Ipratropium Bromide Solution for Inhalation (Laboratoire Unither, Espace Industriel Nord, France) by atomization inhalation (1.25–2.5 mL, twice daily). All drugs were administered for 7 days. In addition to the treatment provided for the control group,the HFCWO group also underwent sputum clearance using HFCWO (20 min, twice daily for 7 days, 10 Hz, at a pressure setting of 4) (Talent Medical Electronics Co., Ltd, Zibo, China). In the event of fever, subjects in either group were given ibuprofen (Shanghai Johnson & Johnson Co., Shanghai, China). If children developed expiratory dyspnea and transcutaneous oxygen saturation SO2<90%, they were given persistent low flow oxygen therapy (1–3L/min).
2.3 Clinical data collection
Upon recruitment, we acquired a range of clinical information from all patients, including gender, age, clinical data related to illness, time of symptom onset, time of symptom remission,respiratory rate and oxygen supplementation. We then calculated the duration of symptomsas the time from the onset of symptoms to remission. The length of stay(LOS) was determined for all patients, as well as the costs involved.
2.4 Lung function testing
Prior to treatment, and after 7 days of treatment, we tested the pulmonary function of each child using a lung function measurement system (AS-507; MINATO Medical Science Co.,LTD.,Osaka,Japan).We recorded a range of parameters, including theforced expiratory volume in 1 s (FEV1)/predicted value, forced vital capacity (FVC)/predicted value, and peak expiratory flow (PEF)/predicted value. All patients were of Chinese ancestry. The predicted values were calculated by using the published predicted valuesfor children’s lung function in Beijing,China(11).
2.5 Imaging and laboratory tests
Chest X-rays,routine blood tests, and C-reactive protein (CRP) tests, were performed immediately on the day of admission and 7 days after treatment. Chest X-rays were compared by a radiologist, who was blinded to the experimental grouping, based on the electronic images of two images taken before and after treatment so as to identify changes in chest abnormalities and create a formal report.
2.6 Therapeutic effects
After 7 days of treatment, we evaluated the efficacy of our treatment plan. The treatment was considered as “effective” if fever, convulsive cough, and other symptoms of the upper respiratory tract,had disappeared. The treatment was considered as “ineffective” if obvious clinical symptoms remained after the treatment had finished, and the chest X-ray suggested no improvement or aggravation (12).
2.7 Data analysis
SPSS 21.0(IBMCorp.,Armonk,NY,USA) was used for all statistical analyses.The Shapiro-Wilk test was used to determine whether data were normally distributed.Normally distributedcontinuous data are expressed as mean ± standard deviation, whilecategorical data are expressed as frequency and percentage. Chi-square tests and independent-sample t-testswere used to compare data between the two groups.
3. Results
3.1 Side effects arising from vibration therapy
Ten children described transient dizziness caused by vibration during HFCWO treatment, although this was well tolerated and disappeared when the treatment had been completed. None of the children experienced side effects, such as an abnormally fast heart rate, shortness of breath, chest distress, or other problems caused by hammer dynamic changes.
3.2 Comparison of baseline data between the HFCWO and control groups
There were 75 patients in the HFCWO group; 53 males (79.7%) males and 22 females (20.3%) with a mean age of 8.01±1.37 years. There were 82 patients in the control group; 62 males (75.6%) and 20 females (24.4%) with a mean age of 7.96±1.37 years. There were no significant differences between the two groups with regards to age, gender, white blood cell count(WBC), respiratory rate or CRP level (P>0.05). Prior to treatment, there were no significant differences between the two groups with respect to FEV1 (79.2±2.51%vs 79±2.48%), FVC (83.1±2.74% vs 83.4±2.69%), or PEF (82±0.86% vs 82±0.85%) (Table 1).
3.3 Comparison of the treatment effects,cost, and length of staybetween the HFCWO and control groups
Following treatment, there were no significant differences in WBC and respiratory ratewhen compared between the two groups. However, the CRP levels of patients in the HFCWO group were significantly lower than those in the control group(7.13±4.39vs 9.53±1.51 mg/L; P<0.05).Although there was no difference inrespiratory rate,but high respiration rate matched for age and gender in the HWCO group had significantly less than the contrcol group(10.1%vs 23.2%; P<0.05)Five children required oxygen in theHFCWO group; this was significantly fewer than the 14 patients in the control group that required oxygen (6.67% vs 17.07%; P<0.05). The total effective rate in the HFCWO group (88%) was significantly higher than that in the control group (75.6%; P<0.05). The duration ofcough in the HFCWO group (5.2±1.2 days) was significantly shorter than that in the control group (5.8±1.5 days; P<0.001). Furthermore, the duration of fever in the HFCWO group (3.6±0.93 days) was significantly shorter than that in the control group (5.1±1.08 days; P<0.001). Following treatment, FEV1 (81.5±1.67% vs 80.3±2.19%; P<0.001), FVC (85.3±2.49% vs 84.2±2.67%; P = 0.007), and PEF (85.5±1.34% vs 84.0±1.05%; P<0.001), were all significantly higher in the HFCWO group than in the control group (Table 2). The proportion of chest X-raysindicating no improvement or aggravation in the HFCWO group(27,36%) was lower than that in the control group(35,42.7%),but the difference showed no statistically significant(P=0.392).The LOS in the HFCWO group was significantly shorter than that in the control group(9.03±1.81vs10.78±2.49 days; P<0.001). Finally, the treatment costs in the HFCWO group were significantly lower than the control group(6263.29±1727.7vs7769.82±2118.65 yuan; P<0.001).