Cardiovascular effects of acute bronchiolitis

Twenty-one children with normal hearts were studied during acute bronchiolitis. Doppler echocardiography showed tricuspid valve regurgitation in 11 patients, many of whom had evidence of raised pulmonary artery systolic pressure. Serial studies in those with severe infection showed that tricuspid regurgitation disappears with clinical improvement.     

婴儿急性毛细支气管炎随访分析

目的：观察毛细支气管炎的转归及其与婴幼儿哮喘的关系。方法：对56例急性毛细支气管炎患儿进行鼻咽部分泌物病毒检测,观察结核菌素试验PPD反应,用ELISA法测定血清IgE、单个核细胞培养上清IL-4、IFN-γ水平。结果：毛细支气管炎发作2年后25%发展为婴幼儿哮喘;哮喘组皮肤PPD阳性率明显低于单纯毛细支气管炎组(χ2=4.123, P<0.05);哮喘组IgE,IL-4高于单纯毛细支气管炎组(t=2.791,2.284,均P<0.01),而IFN-γ比单纯毛细支气管炎组低,差异具有显著性(t=2.27,P<0.05)。结论：婴幼儿哮喘存在TH1/TH2亚群失衡现象;建议PPD试验阴性者复种卡介苗诱导TH1细胞活化以改善预后。     

Nebulized albuterol in acute bronchiolitis

In a double-blind, placebo-controlled trial, 40 infants between 6 weeks and 24 months of age who had a first episode of wheezing and other signs and symptoms of bronchiolitis were randomly assigned to receive either nebulized albuterol (0.15 mg/kg/dose) or placebo (saline solution) for two administrations 1 hour apart. The albuterol therapy resulted in a significantly greater improvement in the accessory muscle score (decreases 0.70 vs decreases 0.30; p = 0.03), oxygen saturation (increases 0.71% vs decreases 0.47%; p = 0.01) after one dose, and in the accessory muscle score (decreases 0.86 vs decreases 0.37; p = 0.02), respiratory rate (decreases 19.6% vs decreases 8.0%; p = 0.016), and oxygen saturation (increases 0.76% vs decreases 0.79%; p = 0.015) after two doses of the drug. The response to therapy was similar in infants younger and those older than 6 months of age. The heart rate rose slightly more in the albuterol group (increases 7.76 from baseline) versus the placebo group (decreases 6.79). There were no other side effects of the treatment. Of the 34 children from whom nasal specimens were obtained by swab for viral identification, 24 had positive test results (21 for respiratory syncytial virus, 1 for parainfluenza, 1 for paramyxovirus, and 1 for influenza A). We conclude that nebulized albuterol constitutes a safe and effective treatment of infants with bronchiolitis.     

急性毛细支气管炎的诊断与治疗

急性毛细支气管炎是由于毛细支气管的炎性肿胀和分泌物阻塞，引起通气功能异常，出现肺气肿或不张，临床上表现为呼气性呼吸困难、肺部有哮鸣音和细湿哕音，是导致婴幼儿住院的主要呼吸道疾病之一。急性毛细支气管炎多见于2岁以下的患儿，尤其在小于6个月的婴儿。     

Implementation of evidence-based management of acute bronchiolitis

OBJECTIVE: Implementation of clinical guidelines is frequently delayed well beyond their dissemination and the publication of clinical evidence. The recently published Australian guidelines for the management of acute viral bronchiolitis (AVB) have been evaluated by assessing the current practice of Australian paediatricians. METHODS: Questionnaire survey of all Australian paediatricians and a review of the literature. RESULTS: Of a total of 891 questionnaires, 555 (62%) were returned. Of the respondents, 373 (67%) treated children with AVB and, of these, 232 (67%) treated 10-50 children per year. A wide variation in management practice for both outpatient and inpatient treatment of AVB was identified. Up to 70% of paediatricians who treated AVB indicated using pharmaceutical agents in their outpatient management (88% in inpatient management), most using these agents 'sometimes' or in high-risk children. Paediatric respiratory physicians tended to use bronchodilators less frequently than general paediatricians. Compared with many countries in Europe, few Australian paediatricians routinely use supplementary drugs in the inpatient managenment of AVB; in particular, bronchodilators (61 vs 7%) and corticosteroids (11 vs 1%) are used far less often. A review of the literature demonstrated that pharmaceutical agents do not influence the course of AVB. CONCLUSIONS: Despite a lack of evidence for their efficacy and the recommendation of the Australian guidelines, pharmaceutical agents are frequently used in the management of AVB by paediatricians in Australia, although far less than reported in a recently published European survey. Guidelines alone are not sufficient to implement change and there is a need for more specific strategies to ensure that children receive appropriate management for this common condition.     

The chest radiograph in acute bronchiolitis

The relationship between clinical severity, as judged by a clinical scoring method, and the degree of radiological change on a chest X-ray, was assessed in 153 children with acute bronchiolitis. There was no statistical correlation between clinical severity and the degree of radiological change. The majority of radiographs were requested on the assumption that it was a useful routine investigation. We suggest that the request for a chest X-ray in acute bronchiolitis should be made only when the need for intensive care is being considered, where there has been an unexpected deterioration in the child's condition or the child has an underlying cardiac or pulmonary disorder.     

Lung function after acute bronchiolitis.

We performed 211 lung function measurements on 93 children in the first year after they had been admitted with acute bronchiolitis. During the convalescent phase of the illness, 77% of the infants were hyperinflated with a thoracic gas volume greater than 40 ml/kg and 3 months later 43% were hyperinflated. Twelve months after the initial illness, 17% still had lung function abnormalities and most of these children have had lower respiratory tract symptoms. For the group as a whole about 60% have had at least one episode of wheezing. Specific conductances were significantly lower in children from atopic families, indicating worse lung function, but the significance of this finding is unclear.     

Sleep apnoea in acute bronchiolitis.

Three- to 4-hour polygraphic sleep studies were carried out in 16 infants aged between 1 and 6 months during and after recovery from acute bronchiolitis. During bronchiolitis 35% of total sleep time was active sleep compared with 31% after recovery. Respiration rate was increased during bronchiolitis and was higher in active sleep and quiet sleep irrespective of the stage of the illness. Apnoeic pauses were invariably shorter than 15 seconds, the mean duration for active sleep and quiet sleep being similar during infection and after recovery. Apnoeic episodes were central in type and generally initiated by a sign or body movements. Preapnoea heart rate was significantly higher than during or after apnoea. Apnoea index (the percentage of time the baby spends apnoeic), apnoea attack rate (the number of episodes of apnoea per unit time), and apnoea percentage (the distribution of episodes of apnoea while in a given sleep state) were increased significantly in quiet sleep during the index illness. Transcutaneous oxygen tension was significantly reduced during the course of infection, but comparable values were obtained in active sleep and quiet sleep during initial and recovery periods. These results show that the main changes in respiration pattern during the course of acute bronchiolitis occur in quiet sleep.     

Salbutamol or mist in acute bronchiolitis

Abstract Background : The role of bronchodilators in the treatment of bronchiolitis remains controversial.
Methods : A double-blind, placebo controlled trial was performed to evaluate the clinical response to nebulized salbutamol. One hundred and fifty-six infants aged between 7 weeks and 24 months who had had an episode of wheezing and other signs and symptoms of bronchiolitis were randomized to three groups as follows: (i) nebulized salbutamol was administered to 52 patients in group I at a dose of 0.15 mg/kg in 2 mL saline; (ii) saline was nebulized to 52 patients in group II and (iii) in group III 52 patients received mist in a tent. All three groups were administered oxygen during the procedures. Treatment was repeated with the same agent after 30 min if the respiratory score was 5 or more. Respiratory rate, heart rate, oxygen saturation and presence of cyanosis, wheezing, retractions were recorded before and after each treatment.
Results : The decrease in the respiratory score was 5.2 ± 1.8, 0.82 ± 2.4 and 1.7 ± 1.3 in group I, II and III, respectively. The decrease in group I was significantly higher than in the other groups. Heart rate was similar between groups. Oxygen saturation decreased in group I without reaching statistical significance.
Conclusions: Salbutamol was shown to be effective and safe in the treatment of acute bronchiolitis.     

Chest physiotherapy in acute bronchiolitis.

Forty four children with acute bronchiolitis were given twice daily chest physiotherapy in addition to standard supportive measures and were compared with 46 controls who were not given physiotherapy. There was no clinically discernable benefit on the course of their illness.     

Ribavirin aerosol for acute bronchiolitis.

A randomised double blind placebo controlled trial of treatment with an aerosolised antiviral agent, ribavirin, was conducted in 26 infants with clinically diagnosed bronchiolitis. Nebulised ribavirin (14 infants) or normal saline aerosol (12 infants) was given for 18 hours a day for at least three days. Respiratory syncytial virus was identified in nasal secretions from 20 cases (10 from both groups). Trends in seven out of eight clinical variables favoured active treatment. Ribavirin aerosol was associated with significantly faster improvement in cough and crepitations and more rapid rate of fall in respiratory and heart rates. In the 20 infants from whose nasal secretions respiratory syncytial virus was identified most variables favoured treatment with ribavirin, with significant reduction in chest recession. No difference was found in the rate of clearance of respiratory syncytial virus. The treatment was well tolerated as judged clinically and from the results of haematological and biochemical studies. The study suggests nebulised ribavirin may have a place in the treatment of some cases of bronchiolitis.     

The management of acute bronchiolitis in infants

Bronchiolitis is a seasonal viral lower respiratory tract illness common in infancy and a major cause of hospitalization in this age group. The course is often self-limiting but drawn out over 2–4 weeks. Investigations are of limited value and the diagnosis is essentially clinical. Mainstay of management is supportive care to maintain oxygenation and hydration. Historically, clinical trials have shown little or no significant benefit of pharmacological therapy in bronchiolitis. Commonly used pharmacological agents include nebulized hypertonic saline, bronchodilators, epinephrine and corticosteroids, oral or inhaled; though their role remains controversial. Recent studies point towards a beneficial effect of nebulized hypertonic saline on clinical severity and length of hospitalization. There also seems to be a promising role of nebulized epinephrine in reducing the need for hospitalization. Home oxygen is increasingly being used in patients with uncomplicated bronchiolitis and on-going hypoxia as an effective way to decrease both hospital admissions and the length of hospital stay.     

Randomized trial of salbutamol in acute bronchiolitis

To test whether nebulized salbutamol (albuterol) is safe and efficacious for the treatment of young children with acute bronchiolitis, we enrolled 83 children (median age 6 months, range 1 to 21 months) in a randomized, double-blind clinical trial. Participants received two treatments at 30-minute intervals of either nebulized salbutamol (0.10 mg/kg in 2 ml 0.9% saline solution) or a similar volume of 0.9% saline solution placebo. Outcome measures were the respiratory rate, pulse oximetry, and a clinical score based on the degree of wheezing and retractions. Patients in the salbutamol arm had significantly greater improvement in clinical scores after the initial treatment (p = 0.04). There was no difference between the groups in oxygen saturation (p = 0.74); patients treated with salbutamol had a small increase in heart rate after two treatments (159 +/- 16 vs 151 +/- 16; p = 0.03). We conclude that salbutamol is safe and effective for the initial treatment of young children with acute bronchiolitis.