Glutathione oxidation correlates with one-lung ventilation time and PO₂/FiO₂ ratio during pulmonary lobectomy

Abstract

Objectives: During lung lobectomy, the operated lung completely collapses with simultaneous hypoxic pulmonary vasoconstriction, followed by expansion and reperfusion. Here, we investigated glutathione oxidation and lipoperoxidation in patients undergoing lung lobectomy, during one-lung ventilation (OLV) and after resuming two-lung ventilation (TLV), and examined the relationship with OLV duration.

Methods: We performed a single-centre, observational, prospective study in 32 patients undergoing lung lobectomy. Blood samples were collected at five time-points: T0, pre-operatively; T1, during OLV, 5 minutes before resuming TLV; and T2, T3, and T4, respectively, 5, 60, and 180 minutes after resuming TLV. Samples were tested for reduced glutathione (GSH), oxidized glutathione (GSSG), glutathione redox potential, and malondialdehyde (MDA).

Results: GSSG and MDA blood levels increased at T1, and increased further at T2. OLV duration directly correlated with marker levels at T1 and T2. Blood levels of GSH and glutathione redox potential decreased at T1−T3. GSSG, oxidized glutathione/total glutathione ratio, and MDA levels were inversely correlated with arterial blood PO₂/FiO₂ at T1 and T2.

Discussion: During lung lobectomy and OLV, glutathione oxidation, and lipoperoxidation marker blood levels increase, with further increases after resuming TLV. Oxidative stress degree was directly correlated with OLV duration, and inversely correlated with arterial blood PO₂/FiO₂.

Keywords:

• Lung lobectomy
• One-lung ventilation
• Oxidative lung injury
• Glutathione oxidation
• Glutathione redox potential
• Malondialdehyde

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Erratum

Acknowledgments

The authors thank Prof Dr José Viña and Prof Dr Federico Pallardó (Department of Physiology, University of Valencia) for their generous help with GSH and GSSG determination.

Disclaimer statements

Contributors J.G.D.L.A. takes responsibility for the integrity of the data. Study concept and design: J.G.D.L.A. Acquisition of data: E.G.D.O., G.G., F.M., R.B., J.P.G., A.D., C.D., J.C. Analysis and interpretation of data: J.G.D.L.A., E.G.D.O., F.M., J.P.G. Drafting of the manuscript: J.G.D.L.A., E.G.D.O. Critical revision of the manuscript: J.G.D.L.A., J.B., G.G., R.G., R.B. Statistical analysis: F.M. Administrative, technical, or material support: A.D., C.D., J.C. Study supervision: J.G.D.L.A.

Conflict of interest None declared.

Ethics approval The Ethic Committee at Hospital Clínico Universitario de Valencia (2006/184) approved the protocol and an informed consent was obtained from each patient.

Additional information

Funding

This work was supported in part by a grant (PI07/0836) from Instituto de Salud Carlos III to José García-de-la-Asunción.