RT Journal Article
SR Electronic
T1 Assessment of VQ abnormalities in patients with scoliosis
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P3301
VO 44
IS Suppl 58
A1 Amelia Robinson
A1 Matt Rutter
A1 Robert Ross Russell
YR 2014
UL http://erj.ersjournals.com/content/44/Suppl_58/P3301.abstract
AB Background - We have recently demonstrated that lung ventilation perfusion abnormalities and shunt can be calculated non-invasively. By varying the inspired oxygen levels (PiO2) and measuring arterial saturation (SaO2), we can construct a surrogate oxygen dissociation curve that allows measurement of VQ and of intrapulmonary shunt. Historical reports (Kafer E, J Clin Invest 1976, p825) suggested that VQ abnormalities were common in scoliosis, and were a cause of arterial hypoxaemia. We wanted to test this in a population of children undergoing scoliosis surgeryMethods - Patients being assessed prior to planned scoliosis surgery were approached.If consented, PiO2 was varied between 14 and 21%, and PaO2 measured using an oximeter. VQ and shunt were calculated using previously described methodology.Results - At the present time 9 patients have been studied. All had idiopathic scoliosis, and had mean forced vital capacity between 78 and 103% predicted. The measured shunt in this group was very low (median 0%), and VQ measurements were all within the normal range (range 0.8 - 1.45). No evidence of abnormal VQ could be found in this group, who all tolerated low PiO2 well.Discussion - Our data do not currently support there being a significant VQ problem in children with idiopathic scoliosis. In comparison the the patients studied by Kafer, ours had a lesser degree of curvature, and this may have influenced the results. Although poor lung function and hypoxaemia may be found in patients with scoliosis, this early evidence suggests that the cause may be other than in VQ mismatch. However studies are needed in patients with more severe disease.