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Chest physiotherapy in paediatric patients hospitalised with community-acquired pneumonia: a randomised clinical trial
  1. Janice Luisa Lukrafka1,
  2. Sandra C Fuchs2,
  3. Gilberto Bueno Fischer3,
  4. José A Flores4,
  5. Jandira M Fachel5,
  6. Jose A Castro-Rodriguez6
  1. 1Department of Physiotherapy, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brasil
  2. 2Department of Social Medicine, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brasil
  3. 3Department of Pediatrics, School of Medicine, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
  4. 4Department of Radiology, School of Medicine, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
  5. 5Department of Statistics, Mathematics Institute, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
  6. 6Departments of Pediatrics and Family Medicine, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
  1. Correspondence to Janice Luisa Lukrafka, Department of Physiotherapy, Universidade Federal de Ciências da Saúde de Porto Alegre, St. Sarmento Leite 245, CEP 90050-170, Porto Alegre, Rio Grande do Sul, Brasil; jllukrafka{at}bol.com.br

Abstract

Background Chest physiotherapy has been used to treat children hospitalised with pneumonia with no clear scientific evidence to support a beneficial effect. The objective of the current study was to evaluate the efficacy of chest physiotherapy as an adjuvant treatment in children hospitalised with acute community-acquired pneumonia.

Methods Children (aged 1–12 years) with a clinical and confirmed radiological diagnosis of pneumonia sequentially admitted to a tertiary children hospital were eligible for this study. Participants were randomly selected to receive a standardised respiratory physiotherapy (positioning, thoracic vibration, thoracic compression, positive expiratory pressure, breathing exercises and forced exhalation with the glottis open or ‘huffing’) three times daily in the ‘intervention group’ or a non-mandatory request to breathe deeply, expectorate the sputum and maintain a lateral body position once a day in the ‘control group’. The primary outcomes were reduction in respiratory rate and severity score (respiratory rate, recession, fever, oxygen saturation and chest x-ray) from baseline to discharge. Secondary outcome was duration of hospitalisation.

Results In all, 72 patients were randomly allocated to the intervention (n=35) or control (n=37) groups. There were no differences at admission on severity of pneumonia between groups. Respiratory rate and severity score significant decreased between admission to discharge within each group; however, there were no differences when comparing groups. Also, there was no significant difference in duration of hospitalisation between the control and intervention groups (6 vs 8 days, p=0.11, respectively).

Conclusions This clinical trial suggests that, in children hospitalised with moderate community-acquired pneumonia, chest physiotherapy did not have clinical benefits in comparison to control group.

  • Respiratory
  • General Paediatrics

https://doi.org/10.1136/archdischild-2012-302279

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    Introduction

    Though chest physiotherapy is not specifically recommended for children with pneumonia,1 it still a common practice in many treatment centres around the world. Postural drainage, percussion, deep breathing and vibration techniques together with controlled coughing are intended to improve the clearance of airway secretions from the lung.2 However there is little evidence to support this practice.

    A randomised clinical trial (RCT) of 55 children with presumed viral pneumonia was performed. Comparing chest x-ray improvement and duration of fever, there was no statistical differences between the chest physiotherapy and control groups.3 In a single-blind RCT, 171 patients (15–75 years.) with acute pneumonia admitted to the hospital were allocated either to receive physiotherapy or advised on expectoration, deep breathing and exercise (control group). There was no evidence in favour of daily physiotherapy. However, patients younger than 47 years, smokers, or patients with interstitial pneumonia had a longer fever duration and hospital stay in the chest physiotherapy group; this highlights the importance of performing RCTs in a younger population.4 A recent RCT performed with 98 children hospitalised with acute pneumonia failed to confirm that chest physiotherapy as an adjunct to standard treatment hastens the clinical resolution of pneumonia.5

    The aim of this study was to assess the efficacy of the use of chest physiotherapy on children hospitalised with primary community-acquired pneumonia.

    Methods

    Setting and participants

    Children (aged 1–12 years) hospitalised with a clinical and radiological confirmed diagnosis of acute community-acquired pneumonia were assessed for eligibility for the study. Clinical diagnosis criteria for pneumonia were: cough, tachypnoea (respiratory rate≥40 breaths/min in children aged 12–59 months and ≥30 breaths/min in children aged 5–12 years) and fever.6 Radiological diagnosis of pneumonia was considered if the chest x-ray had lobar, segmental or bronchopneumonia, or pleural effusion within the first 48 h.7 Patients who were severely ill, such as those hospitalised in intensive care units, with pleural effusion treated with chest drainage, atelectasis detected by x-ray, history of pneumonia or pleural effusion in the previous 6 months, or other pulmonary underlying diseases, heart diseases, cerebral palsy or immune deficiency, were excluded.

    Study design and protocol

    This RCT (NCT#01017081) was carried out during a single calendar year at the Hospital da Criança Santo Antônio—Complexo Hospitalar Santa Casa de Porto Alegre, Porto Alegre, Brazil. The Ethics Committee of the Institution approved this protocol and a written consent for participation in the study from each child's parents or relatives was obtained. After signing the consent form, children were randomly assigned to the chest physiotherapy group (intervention) or to the control group, according to age group. All patients received antibiotic treatment and oxygen support if clinically indicated.

    The randomisation was performed by an epidemiologist using a computerised random number generator to select blocks of three and four. A separate randomisation procedure was performed in each of two age group subsets (12–59 months and 5–12 years). Randomisation was concealed using sequentially numbered opaque envelopes by the senior investigator.

    Children younger than 5 years of age in the intervention group received a standardised chest physiotherapy protocol: the children were positioned in a high side lying position or high sitting position, and received manual thoracic vibration, thoracic compression, positive expiratory pressure and artificially stimulated cough with suction, when necessary. A physiotherapist performed the thoracic vibration with cupped hands on the ventral, lateral and dorsal side of the thorax of each patient during exhalation and inspiration. Thoracic compression was delivered by the physiotherapist placing their hands on both sides of the lower part of the thorax and manually compressing the thorax during expiration. Positive expiratory pressure was conducted through a spring-loaded valve, containing 10 cm of water, connected to a ventilation mask. Children aged 5 years or older were requested to perform the same procedures in addition to the breathing exercises, and a forced expiratory technique, consisting of one or two ‘huffing’ breaths (forced exhalation with the glottis open) followed by a period of relaxed, controlled diaphragmatic breathing. All procedures were carried out three times per day, for a period of 10–12 min, during the whole hospitalisation period, as previously reported.8–12 Directed coughing, artificially stimulated cough and removal of airway secretion by suction were applied when necessary.

    Patients in the control group (all ages) received a recommended, non-mandatory request to maintain lateral positioning to improve air exchange, to cough in order to clear secretion, and to perform diaphragmatic and deep breathing, for 5 min, once a day, during the whole hospitalisation.

    Outcomes and follow-up

    Children were clinically evaluated at baseline and at discharge. A standardised protocol was adopted to record respiratory rate (two measurements, assessed during a full minute with an interval of 10 min), temperature (two measurements during the 24 h period), nasal flaring, suprasternal, intercostal and subcostal recession and transcutaneous oxygen saturation (measured using a Ohmeda Medical 3700 pulse oximeter; Ohmeda Medical, Madison, Wisconsin, USA). A chest x-ray was performed at admission and at discharge, and during the hospitalisation if the doctor considered it necessary.

    Chest physiotherapy and clinical evaluation were performed by certified undergraduate students of physiotherapy. Clinical assessment was standardised by a paediatric pulmonologist. An experienced physiotherapist trained and supervised the staff performing the chest physiotherapy and the guidance given to the control group. Staff training sessions were scheduled every 3 months to assure the maintenance of standardisation of the procedures by the research team.

    The primary endpoints were the reduction of respiratory rate and score of severity. The latter was based on the presence or absence (0 or 1) of: tachypnoea (respiratory rate ≥40 breaths/min in children aged 12–59 months or ≥30 breaths/min in children aged 5–12 years);13 ,14 suprasternal, intercostal and subcostal recession; desaturation (transcutaneous oxygen≥95%); fever (temperature≥37.5°C); and pleural effusion on chest x-ray. The score of severity was computed by adding the number of signs (see table 1), and was measured at baseline and at discharge from the hospital. Most of the discharges occurred during the fifth and seventh days.

    View this table:
    Table 1

    Severity score

    The study radiologist, statistician and epidemiologist involved in evaluating the outcomes of this RCT did not take part in the clinical attendance and therapeutic decisions. The same paediatric radiologist examined all chest x-rays. The quality of the information derived from the chest x-ray was assessed by randomly repeating 10% of the x-ray interpretations. The overall agreement for the intraobserver index for all radiographic diagnosis was 85%, and the κ coefficient was good for lobar (κ=0.66) and bronchopneumonia (κ=0.57) and poor for segmental pneumonia (κ=0.38).

    Statistical analysis

    A total sample of 64 subjects was required to detect a mean difference of 1.0±1.2 in the severity score, with 90% power, at a significance level of 0.05 (two tailed).

    The data were expressed as number of cases, mean±SD or median (interquartile interval). Continuous variables were compared using the Student t test for normally distributed variables, and the Mann–Whitney test was used for variables with non-normal distribution. The χ2 test was used to compare categorical variables and Yates’ correction used for dichotomous variables. The comparison of variables as to time, group and group–time interaction was made by means of the variance analysis of repetitive measures. The estimate of survival curves was made through Kaplan–Meyer curves. The log-rank χ2 test was used to compare survival curves. Patients were analysed in the groups to which they were originally randomly assigned, using intention-to-treat analyses. The level of statistical significance used was p<0.05, and tests were two tailed. The data were analysed using SPSS, V.13.0 (SPSS, Chicago, Illinois, USA).

    Results

    Of 362 potentially eligible patients, 262 did not fulfil the inclusion criteria, 19 had pneumonia not detected within 48 h of hospitalisation and 2 refused to participate (figure 1). In all, 79 patients were randomised to either the intervention group (n=38) or control group (n=41). After the randomisation, 4 patients underwent chest drainage (3 in the intervention group) and 3 patients had atelectasis detected by chest x-ray (all in the control group); therefore, 67 patients (n=35 in the intervention and n=37 in the control) remained in the study and follow-up. There were no deaths.

    Figure 1
    Figure 1

    Flow diagram of the trial.

    Patients allocated to the physiotherapy group received on average of 98% of the planned sessions, whereas those allocated in control group received 100%. Antibiotic treatment was administered to all children during hospitalisation, in most cases as monotherapy. The first line of treatment was intravenous penicillin (73.0% in the control group and 71.4% in the intervention group) and cefuroxime (10.8% and 20.0%, respectively).

    At admission, there were no significant differences in demographic and clinical characteristics among children in intervention and control group (table 2). There were slightly more children, although not significantly so, in the intervention group with <−2 weight-for-height z score (11.4 vs 5.4, p=0.4) and pleural effusion than controls (28.6 vs 10.8, p=0.06), table 2.

    View this table:
    Table 2

    Baseline characteristics of patients according to the randomised groups

    Respiratory rate and severity score (primary outcomes) were similar at baseline between groups; they both significantly (p<0.001) improved from baseline to discharge within each group (table 3). However, there were no differences between the intervention and control groups on these primary outcomes at discharge. Also, the duration of hospitalisation (secondary outcome) was similar between groups (median of 6 days (95% CI 5.1 to 6.9) for the control group and 8 days (95% CI 5.1 to 10.9) for the intervention group, p=0.11). Duration of hospitalisation, using Kaplan–Meyer curve by log-rank χ2 test, was similar when comparing groups (figure 2).

    View this table:
    Table 3

    Assessment of clinical outcomes according to the groups of randomisation

    Figure 2
    Figure 2

    Kaplan–Meyer curve of duration of hospitalisation (days) among intervention and control patients.

    Discussion

    This RCT showed no additional beneficial effect of chest physiotherapy, as an adjuvant treatment, for children hospitalised for acute community-acquired pneumonia. The present study supports the guidelines for the management of pneumonias in paediatric patients.1 Recent British Thoracic Society guidelines for pneumonia management stated (grade of recommendation: ‘A–’) that chest physiotherapy is not beneficial and should not be performed in children with pneumonia.15 Other international guidelines,16–18 do not state specific recommendations, suggesting that their use has been prescribed based on the analogy with patients with cystic fibrosis, where physiotherapy is useful.19–21

    Chest physiotherapy has been, and continues to be, widely used on belief of the potential benefits in evacuating inflammatory exudates and tracheobronchial secretions, removing airway obstructions, reducing airway resistance, enhancing gas exchange and reducing the work of breathing.2 However, even in acute bronchiolitis, where airway resistance and obstruction is highly compromised, a recent meta-analysis reported that chest physiotherapy did not reduce the length of hospitalisation, change oxygen requirements or lead to clinical improvement in children hospitalised by acute bronchiolitis.22

    Our results are in according with previous trials on efficacy of chest physiotherapy in community-acquired acute pneumonia performed on children,3 ,5 adolescents/adults,4 or adults.23 A lack of benefit was shown in an RCT of 55 children, but the method of randomisation used was considered poor.3 A recent RCT in 98 children hospitalised with acute pneumonia showed no beneficial effect of physiotherapy.5

    A possible explanation for the absence of benefit is that respiratory physiotherapy could not play a role if there is no secretion in the airway. It would be worthy where coughing is not effective to eliminate secretion, mainly in very young or uncooperative paediatric patients. In addition, patients with pneumonia who had obstruction of the lower airways are more likely to benefit from respiratory physiotherapy.24 ,25 However, a recent large multicentre RCT performed in 496 infants hospitalised with acute bronchiolitis showed no effect of chest physiotherapy (increase exhalation technique and assisted cough) on the time to recovery.26

    The present study has some limitations that should be considered in the analysis and interpretation of the results. First, the absence of an objective and sensitive test that allows for the establishment and quantification of the improvement of pneumonia in a short time interval. Respiratory rate has been used as one of the main diagnostic criteria for pneumonia,6 ,13 and the reduction in respiratory rate could be a potential endpoint. In the present study, there was no difference in respiratory rate at discharge from the hospital between groups. A chest x-ray7 could be the best test to detect pneumonia recovery, but is unable to detect alterations in short intervals such as in our study.27 Spirometry could also be used to evaluate clinical improvement; however, most children with pneumonia were younger than 5 years of age, where performing spirometry may generate unreliable results. Consequently, we adopted a set of signs that may be easy detected on clinical examination in order to create a score of scores.28 The length of hospitalisation stay was used as a secondary endpoint, and it was no different between groups. It is known that the decision about the duration of hospitalisation varies among doctors29 and hospitals.30 However, our study was conducted at a single institution, and the similarity in demographic characteristics and antimicrobial treatment between groups suggests that the doctor/facility profiles were unlikely to have biased length of hospitalisation. Second, no test for aetiology of pneumonia was performed; however, the proportion of antibiotics used between groups was similar. Third, we did not include cases of complicated pneumonia nor with profuse secretion production; therefore, this study cannot be extrapolated to those cases. Future studies need to be performed in these particular scenarios. Even though this RCT had a relative small number of participants, we reached the estimated number of subjects calculated for significance.

    In conclusion, the present results showed that among patients who were moderately ill and hospitalised with community-acquired pneumonia, respiratory physiotherapy did not have a clinical benefit in comparison to a control group. Therefore, there is no advantage in prescribing respiratory physiotherapy to paediatric patients hospitalised with non-complicated community-acquired pneumonia.

    What is already known on this topic

    • Guidelines suggest that chest physiotherapy is unlikely to be effective in children with acute pneumonia.

    • Chest physiotherapy is, however, widely used throughout the world in this scenario.

    What this study adds

    • Chest physiotherapy had no beneficial effect in children hospitalised with community-acquired pneumonia.

    Acknowledgments

    The authors thank the physiotherapy undergraduate students of the Rede Metodista de Educação do Sul for helping with the data acquisition and the Postgraduate Programme in Medical Sciences, where the Masters degree of JLL was obtained.

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    View Abstract

    Footnotes

    • Contributors JLL: planning, conducting investigations, reporting and responsibility for overall content as guarantor. SCF, GBF, JAF, JMF: planning, conducting investigations and reporting. JAC-R: reporting.

    • Funding This study was partially supported by the Brazilian National Council on Scientific and Technology Development (CNPq), as a research grant to SCF. CNPq had no involvement with the study.

    • Competing interests None.

    • Patient consent Obtained.

    • Ethics approval Ethics Committee of Hospital da Crianza Santo Antonio-Complexo Hospitalar Santa Casa de Porto Alegre, PortoAlegre, Brazil.

    • Provenance and peer review Not commissioned; externally peer reviewed.