@article {Kurz358, author = {Johanna Manuela Kurz and Ben Spycher and Romy Rodriguez and Reta Fischer Biner and Philipp Latzin and Florian Singer}, title = {Blood gas analysis to predict survival in patients with cystic fibrosis}, volume = {56}, number = {suppl 64}, elocation-id = {358}, year = {2020}, doi = {10.1183/13993003.congress-2020.358}, publisher = {European Respiratory Society}, abstract = {Background: Partial pressures of carbon dioxide and oxygen (PaCO2, PaO2), and oxygen saturation (SaO2) from blood gas analysis (BGA) characterize pulmonary gas exchange. Studies on the prognostic value of PaCO2, PaO2 and SaO2 to predict survival in individuals with Cystic Fibrosis (CF) are scarce.Methods: Retrospective cohort in 215 CF patients aged >=3 years in 1980-2006. Inclusion criteria were: clinical stability, availability of BGA performed on arterialized capillary blood from the earlobe, and lung function. Study endpoint was the association (hazard ratio, HR) of PaCO2 (mmHg), PaO2 (mmHg) and SaO2 (\%) with the compound outcome death or lung transplantation (LTX) determined in 12/2018. We fitted cox proportional hazard regression models including lung clearance index (LCI) and FEV1, anthropometric characteristics and clinical variables. We kept variables if p\<0.2.Results: Mean (SD) patient{\textquoteleft}s age was 14.2 (8.2) years, 48\% females. Mean (SD) follow-up was on average 27.0 (8.9) years, resulting in 3813.3 person-years. Until 12/2018, 42\% (90/215) died or received LTX. Crude HR [95\%CI] for PaCO2, PaO2 and SaO2 were 1.35 [1.04, 1.77], 1.99 [1.55, 2.55], 1.59 [1.33, 1.89]. The associations were weakened after full adjustment: 1.19 [0.82, 1.73], 1.54 [1.02, 2.32], 1.41 [1.08, 1.82]. The final model for PaCO2 included: LCI, FEV1, sex, age and number of hospitalizations, 1.17 [0.83, 1.66]; for PaO2: LCI, sex, age and BMI, 1.73 [1.24, 2.40], and for SaO2: LCI, FEV1, sex and age 1.38 [1.07, 1.79].Conclusion: Pulmonary gas exchange indices are associated with survival in individuals with CF. Consistently, ventilatory efficiency (LCI), sex and age were revealed to partially explain these associations.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 358.This abstract was presented at the 2020 ERS International Congress, in session {\textquotedblleft}Respiratory viruses in the "pre COVID-19" era{\textquotedblright}.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).}, issn = {0903-1936}, URL = {https://erj.ersjournals.com/content/56/suppl_64/358}, eprint = {https://erj.ersjournals.com/content}, journal = {European Respiratory Journal} }