Does the Transient Decrease in Mixed Venous Oxygen Saturation and Jugular Venous Hemoglobin Saturation During the Rewarming Phase in a Cardiopulmonary Bypass Merely Reflect a Recovery of the Metabolic Rate? A Case Report

Abstract

Maintaining the balance between oxygen supply and demand during a cardiopulmonary bypass (CPB) is a key issue in the anesthetic management of cardiovascular surgery. Although many reports have described this balance at a constant, low body temperature, little is known about the balance during the cooling and the rewarming phase of CPB. Nakajima et al. [1] reported that jugular venous hemoglobin saturation (SjO₂) decreased during the rewarming phase of CPB, and that rapid rewarming produced a pronounced decrease in SjO₂. We analyzed retrospectively the intraoperative changes in SjO₂, mixed venous oxygen saturation (SV̄O₂), and oxygen consumption (V̇O₂) in three patients who underwent reconstruction of the thoracic aorta, two of whom developed postoperative neurological deficits.