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Respiratory Muscle Strength in Healthy Children Aged 6 Years and Under: An Observational Study
Kayley Noxell1, Emily Acquaye2, Vicky MacBean2
1Therapeutic Services Ltd Physiotherapy, St John's, St. John's, Newfoundland, Canada.
Insights
This study provides crucial reference data for maximum inspiratory (PImax) and expiratory (PEmax) muscle strength in children under seven. These findings are vital for diagnosing and managing pediatric neuromuscular diseases.
Area of Science:
- Pediatric Pulmonology
- Respiratory Physiology
- Neuromuscular Disorders
Background:
- Respiratory muscle strength assessment is vital for neuromuscular disease management.
- Establishing normative data in young children is critical for accurate clinical interpretation.
- Existing reference data for respiratory pressures in infants and young children are limited.
Purpose of the Study:
- To establish reference data for maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax) in healthy children aged six years and under.
- To provide a contiguous reference range from infancy through school age.
- To assess the repeatability of PImax and PEmax measurements in this age group.
Main Methods:
- Recruited healthy, term-born children aged 0.08-6.85 years.
- Measured PImax and PEmax using a face mask and pressure transducer, with efforts induced by crying or volitional effort.
- Calculated age, height, weight, BMI, and assessed measurement repeatability.
Main Results:
- Technically acceptable PImax and PEmax data were obtained from 45 and 38 children, respectively.
- PImax showed a significant inverse relationship with age (Spearman's rho -0.339, p=0.046).
- Predicted PImax was 120 + (-3.89xage); mean PEmax was 80.3 (21.7) cmH2O, with no significant gender differences.
Conclusions:
- This study presents the first contiguous reference range for PImax and PEmax from infancy to school age.
- The provided reference data and repeatability information are valuable for clinical use in pediatric respiratory and neuromuscular assessments.
- These data facilitate the interpretation of respiratory muscle strength in young children, aiding in diagnosis and management.
Study Question:
Measurement of respiratory muscle strength is important in the assessment and management of neuromuscular diseases. Reference data are essential for interpretation of clinical findings, but are lacking in infants and young children. This study aimed to provide reference data for maximum inspiratory (PImax) and maximum expiratory (PEmax) pressures in children aged 6 years and under.
Materials And Methods:
Healthy, term-born children were eligible for inclusion. Age, height, weight and BMI were recorded, and height/weight/BMI-for-age percentiles calculated. PImax and PEmax were measured using a tight-fitting face mask attached to a pressure transducer during maximal inspiratory and expiratory efforts respectively, induced via crying in younger participants and volitionally in older children. The greatest pressure was reported from three values within 20% of one another. Repeat measurements were obtained within a week where possible.
Results:
Sixty-nine children aged 0.08-6.85 years were recruited, from whom technically-acceptable PImax and PEmax data were obtained in 45 and 38 cases respectively. PImax was significantly and inversely related to age (Spearman's rho -0.339, p = 0.046); PEmax was not related to any anthropometric characteristics. Neither PImax or PEmax differed between male and female participants. Predicted PImax was 120 + (-3.89xage); mean (SD) PEmax was 80.3 (21.7) cmH2O. Repeatability coefficient was 17.2 cmH2O for PImax and 26.3 cmH2O for PEmax (based on eleven and nine children respectively).
Answer To The Study Question:
This study provides the first contiguous reference range from infancy through to school age. Reference data are provided for PImax and PEmax along with information on repeatability.
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