The influence of supine posture on chest wall volume changes is higher in obese than in normal weight children

Abstract

The objective of this study was to analyze thoraco-abdominal kinematics in obese children in seated and supine positions during spontaneous quiet breathing. An observational study of pulmonary function and chest wall volume assessed by optoelectronic plethysmography was conducted on 35 children aged 8-12 years that were divided into 2 groups according to weight/height ratio percentiles: there were 18 obese children with percentiles greater than 95 and 17 normal weight children with percentiles of 5-85. Pulmonary function (forced expiratory volume in 1 s (FEV1); forced vital capacity (FVC); and FEV1/FVC ratio), ventilatory pattern, total and compartment chest wall volume variations, and thoraco-abdominal asynchronies were evaluated. Tidal volume was greater in seated position. Pulmonary and abdominal rib cage tidal volume and their percentage contribution to tidal volume were smaller in supine position in both obese and control children, while abdominal tidal volume and its percentage contribution was greater in the supine position only in obese children and not in controls. No statistically significant differences were found between obese and control children and between supine and seated positions regarding thoraco-abdominal asynchronies. We conclude that in obese children thoraco-abdominal kinematics is influenced by supine posture, with an increase of the abdominal and a decreased rib cage contribution to ventilation, suggesting that in this posture areas of hypoventilation can occur in the lung.

Lung function in obese children and adolescents without respiratory disease: a systematic review

“…Therefore, including children with previous respiratory diseases could evolve into sampling (selection of individuals), confounding (proven impact on outcomes) or information bias (previous knowledge of an existing problem). In this context, 66.7% (22/33) [ 12 – 15 , 17 – 21 , 25 , 26 , 29 , 32 – 37 , 39 – 42 ] of the studies excluded individuals with respiratory diseases, 27.3% (9/33) [ 16 , 22 – 24 , 27 , 28 , 30 , 31 , 38 ] did not mention respiratory diseases as a factor of exclusion or non-inclusion, and 6% (2/33) [ 11 , 43 ] excluded only individuals with a history of smoking. Among the studies that excluded previous respiratory diseases, several exclusion criteria could be observed: some authors excluded only individuals with exacerbation of asthma or cough; others excluded any respiratory conditions that might impair the evaluation; and others used standardized instruments such as the ISAAC questionnaire (The International Study of Asthma and Allergies in Childhood).…”

“…The articles included were produced in 18 countries, with a predominance of European (8) [ 21 – 23 , 31 , 34 , 35 , 40 ], South American (8) [ 17 , 18 , 26 , 32 , 33 , 37 , 39 , 41 ] and Asian (7) [ 11 , 13 , 15 , 27 , 30 , 31 , 42 ] countries. Also, 4 studies from North America were included [ 19 , 24 , 38 , 43 ], as well as one from Central America [ 29 ], one from Oceania [ 20 ] and four from intercontinental countries ( three Euroasians [ 14 , 25 , 36 ] and one from Asia and Oceania [ 12 ]).…”

“…There was no uniform definition of obesity among studies: 27.3% (9/33) [ 11 , 14 , 15 , 20 , 35 – 37 , 40 , 42 ] used references by Cole et al [ 45 – 47 ]; 21.2% (7/33) [ 12 , 17 , 19 , 26 , 29 , 38 , 43 ] used the criteria established by the Center for Disease Control and Prevention (CDC); 15.1% (5/33) [ 13 , 18 , 33 , 39 , 41 ] used the definition of the World Health Organization (WHO); 12.1% (4/33) [ 16 , 24 , 32 , 34 ] did not mention any references for the definition of obesity; and 27.3% (9/33) [ 14 , 21 – 23 , 25 , 27 , 28 , 31 , 36 ] used references according to their countries of origin. Two [ 14 , 36 ] of the studies mentioned above, used references by Cole et al [ 45 – 47 ] in addition to references according to their countries of origin.…”

“…Spirometry was the most commonly used tool to assess lung function, i.e., in 93.9% (31/33) [ 11 – 24 , 26 , 27 , 29 – 43 ] of the studies. Next, body plethysmography and measurement of the respiratory muscle strength (RMS) were the most used tools in 12.1% (4/33) [ 15 , 19 , 40 , 43 ] and 9.1% (3/33) [ 18 , 37 , 41 ] of the studies, respectively. Optoelectronic plethysmography (OEP) [ 23 , 37 ], impulse oscillometry (IOS) [ 28 , 33 ] and peak expiratory flow measured by peak flow meter (PFE) were included in the analyses of 6.1% (2/33) [ 25 , 32 ] of the studies.…”

“…Lung function was altered by abdominal and subcutaneous fat, and skinfolds were more sensitive to measure adiposity when compared to anthropometric data. The best indicator of adiposity in the analysis of lung function in males was the triceps skinfold Rosa et al [ 37 ] (2014) - Brazil To evaluate RMS by maximum respiratory pressure in healthy, schoolchildren with overweight and obesity, and to identify whether the anthropometric and respiratory variables are related to the outcomes Yes (ISAAC) Cross-sectional 90 school children aged 7 to 9 years (30 – with obesity, 30 – with overweight and 30 – HC Spirometry (PIKo-1, Spire Health, USA) and RMS (one-way valve digital manovacuometer (MVD 300, G-MED, Brazil) Spirometry: ATS/ERS - sitting FMR: ATS - sitting FEV 1 , MIP, MEP There was higher MIP in HC when compared to the others. The correlation of age with FEV 1 , MIP and MEP was (+), and of MIP with BMI (−).…”