ContextDeferasirox, an iron chelator, can potentially reduce intraoperative right-to-left shunt and improve oxygenation in patients undergoing thoracic surgery requiring one-lung ventilation (OLV) by potentiating hypoxic pulmonary vasoconstriction (HPV).AimThe aim was to determine the effect of deferasirox on the intraoperative shunt fraction (SF) of patients undergoing thoracic surgery using OLV.Study design and settingsThis was a prospective, single-blind, randomized, controlled study. The study was conducted at a tertiary-care hospital.MethodsBefore surgery, 64 patients were allocated to two groups comprising 32 patients each. Group D patients were administered deferasirox, while those in group C were given a placebo. We included patients with the American Society of Anesthesiologists physical status III or IV, aged 18-60 years, undergoing elective thoracic surgery needing OLV. SF was the primary outcome variable. Secondary outcome variables were arterial oxygen tension (PaO2), peripheral oxygen saturation (SpO2), the ratio of PaO2and inspired oxygen concentration (P/F), and complications such as desaturation episodes, hypotension, and tachycardia.ResultsBaseline and postoperative values of outcome variables were statistically similar in both groups. Intraoperative values of SF were lower and PaO2, SpO2, and P/F were higher in group D. The incidence of intraoperative desaturation was lower in group D.ConclusionWe conclude that pre-treatment with deferasirox reduces intraoperative SF and improves oxygenation during thoracic surgery using OLV.