Interpreting Spirometry Spirometer

1 interpreting spirometry

1.1 standard guidelines
1.2 motivations
1.3 implications
1.4 altering interpretations

interpreting spirometry

even numerical precision spirometer can provide, determining pulmonary function relies on differentiating abnormal normal. measurements of lung function can vary both within , among groups of people, individuals, , spirometer devices. lung capacity, instance, may vary temporally, increasing , decreasing in 1 person’s lifetime. result, ideas constitutes “normal” based on one’s understanding sources of variabilities , can left interpretation.

traditionally, sources of variation have been understood in discrete categories, such age, height, weight, gender, geographical region (altitude), , race or ethnicity. global efforts have been made in 20th century standardize these sources enable proper diagnosis , accurate evaluation of pulmonary function. however, rather further aiming understand causes of such variations, primary approach dealing observed differences in lung capacity has been “correct for” them. utilizing results comparative population studies, attributes empirically factored “correction factor.” number utilized form personalized ‘reference value’ defines considered normal 1 individual. practitioners may thereby find percent deviation predicted value, known ‘percent of predicted,’ , determine whether someone’s lung function abnormally poor or excellent.

in particular, ‘race correction’ or ‘ethnic adjustment’ has been computer programmed modern-day spirometer. preconceived notions ‘white’ people have greater pulmonary function embedded in spirometer measurement interpretation , have been reinforced through medical stereotyping. in united states, spirometers use correction factors of 10-15% identified ‘black’ , 4-6% identified ‘asian.’

standard guidelines

in 1960, european community coal , steel (eccs) first recommended guidelines spirometry. organization published predicted values parameters such spirometric indices, residual volume, total lung capacity , functional residual capacity in 1971. american thoracic society/european respiratory society recommends race-specific reference values when available. today, national institute occupational safety , health’s spirometry training guide linked centers disease control , prevention’s website notes use of race correction , race-specific reference value in step 4 of “normal” spirometry.

motivations

the use of reference values , discrete categorizations of sources of variability has been motivated ideas of anthropometry , vital capacity. studies have looked @ relationship between anthropometric variables , lung function parameters.

implications

the use of reference values has far not accounted social labelling of race , ethnicity. determinations subjective or silently done practitioner. concern of utilizing reference values misdiagnosis.

evaluation of vital capacity has influenced other sectors of life other medicine well, including evaluation of life insurance applicants , diagnosis of tuberculosis.

regarding gender, population studies have indicated no difference based on gender. notably, spirometers have been used evaluate vital capacity in india since 1929, recording statistically significant difference between males (21.8 ml/cm) , females (18 ml/cm). additionally, 1990, around half of pulmonary training programs in both united states , canada adjusted race , ethnicity.

the spirometer popularized notions of race corrections , ethnic adjustments, suggested black individuals have weaker lungs white individuals. example, thomas jefferson noted physical distinctions between different races such difference in structure of pulmonary apparatus, made black individuals more tolerant of heat , less of cold, whites. jefferson s theories encouraged speculation on natural conditioning of blacks agricultural labor on southern plantations in u.s. samuel cartwright, slavery apologist , plantation owner, used spirometer make claim black people consumed less oxygen white people in addition racial ‘peculiarities’ laid out in new orleans medical , surgical journal described racial differences in respiratory system , implication of them on labor.

south african studies utilized spirometer address racial , class differences. eustace h. cluver conducted vital capacity measurement research @ university of witwatersrand , found poor white people had physical unfitness attributable environmental issues rather genetics. using these studies, cluver argued south african association advancement of science during world war 2 improving both nutrition , physical training programs produce wealth , win war increasing working capacity of individuals across races labor necessary achieve these ends. racism , spirometer intersected again in these studies when further research done on effects of physical training on poor white recruits; vital capacity studies showed ‘the poor-white biologically sound , can turned valuable citizen’ no comment made on outcome of black south africans.

beyond united states , south africa, spirometer used in racial studies in india in 1920s. researchers found vital capacity of indians smaller of westerners.

altering interpretations

many have questioned whether current standards sufficient , accurate. multiethnic society develops, racial , ethnic origin factor becomes more , more problematic utilize. ideas connecting ethnicity lack of nutrition , birthplace in poor country become invalid people immigrate , may born in richer nations.