Body plethysmographic study of specific airway resistance in a sample of healthy adults

Abstract

sRaw is a reliable parameter; therefore, we propose that the lower and upper 95% confidence limits should be considered as reference values for adults of both genders, regardless of age. The availability of reference values may be useful in clinical practice and research.

Lung volumes and airway resistance in patients with a possible restrictive pattern on spirometry

“…Only satisfactory, reproducible loops were accepted. The predicted values used for calculation were those proposed by Piatti et al 11 Values above 8.0 cmH 2 O/s in females and 8.6 cmH 2 O/s in males were considered high (mean ± 1.64 SD). …”

“…It is possible that Gaw alone is abnormal in patients with bronchiolitis. 10 In 2012, reference values for specific Raw were derived from a large sample of healthy adults 11 …”

Pletismografía corporal: recomendaciones y procedimiento

“…20 Para adultos entre 18 y 65 años se proponen los valores de LSN (> p95) por grupo de edad y género para sRaw 0.5 , en mujeres < 30 años de 6.18 cmH 2 O/s, de los 31-45 años 5.95 cmH 2 O/s, entre 46-60 años 6.35 cmH 2 O/s, y para > 60 años 6.68 cmH 2 O/s; y en hombres < 30 años 6.37 cmH 2 O/s, de 31-45 años 6.18 cmH 2 O/s, entre 46-60 años 6.78 cmH 2 O/s, > 60 años 6.81 cmH 2 O/s. 21 Las pruebas de broncodilatación o broncoprovocación consumen tiempo y no están adecuadamente estandarizadas en adultos; en niños se propone una caída > 3 desviaciones estándar, correspondiente a un cambio de 25% del predicho. 20 Para prueba de reto bronquial se considera positivo un aumento en la sReff duplicada y que excede el valor de 2kPa o bien una caída de sGaw en 35-40%.…”

Poor standardisation of plethysmographic specific airways resistance measurement despite widespread use

“…Tidal breathing measurement offers feasibility across a wide age range, and a relatively stable index with which to distinguish effects of disease from those of growth and development [6]. Both adult and paediatric reference data exists [7,8]; however, the wide variation in methodology existing between centres has recently been highlighted [8], and sR aw remains one of the few lung function measurements without formal standardisation guidelines [9]. Despite the wide availability of plethysmographic equipment in lung function laboratories, its use is frequently confined to lung volume measurements.…”

“…Until standardisation has been achieved, these authors would advise centres to adhere to existing recommendations [8] and interpret sR aw results with caution. @ERSpublications sRaw is widely used but results should be interpreted with caution until its recording is better standardised http://ow.ly/QvJRJ Two studies, demonstrated that LCI0.5 can be performed in school age children with CF with the same diagnostic performance as LCIstd [5,6] and a recent study [7] showed LCI0.5 is sensitive to improvements with dornase alpha and hypertonic saline in CF. We aimed to investigate the utility of shortened washouts in school age children with asthma, PCD and CF, and to assess the sensitivity of change in LCI to two interventions (intravenous antibiotics in CF [8] and intramuscular triamcinolone injection in severe asthma [9]).…”