Abstract
Background: Regional saturation of oxygen (rSO2), also known as “tissue oxygen saturation” or “local mixed blood oxygen saturation”, indicates the overall oxygen saturation including the arteries, veins and capillaries. The change in the balance of oxygen supply and demand can be determined by measuring this value. Although protection of the patient’s brain is emphasized in cardiopulmonary arrest, no studies have investigated tissue oxygenation of the brain during resuscitation.
Objective: To clarify serial changes in cerebral rSO2 during resuscitation of patients with out-of-hospital cardiac arrest.
Methods: We retrospectively analyzed date from patients with out-of-hospital cardiac arrest in whom cerebral rSO2 were measured serially between March 2008 and March 2010. Patients were divided into the ROSC (return of spontaneous circulation) (+) group, ROSC (-) group, and PCPS (percutaneous cardiopulmonary support) group. Normal range of rSO2 was determined from 15 healthy patients to be 71.2±3.9%.
Results: The ROSC (-) group consisted of 25patients (mean age, 71.0±15.9 [mean±SD] years), the ROSC (+) group 13 patients (72.1±9.6 years), and the PCPS group 5 patients (54.4±15.8 years). Chest compression only could not increase cerebral rSO2, but rSO2 markedly increased with ROSC. Mean rSO2 at ROSC was 43.2±14.1%, and it increased significantly after 10 minutes (55.7±12.3%; p<0.05) and 15 minutes (59.7±8.5%; p<0.01). In the PCPS group, rSO2 values were 63.0±8.8% after 5 minutes, 66.2±5.7% after 10 minutes, and 68.1±4.6% after 15 minutes, significant increases compared with 48.4±8.9% at the time of PCPS application (all, p<0.0001).
Conclusions: Chest compression only could not increase cerebral rSO2, but it increased gradually with ROSC. Cerebral rSO2 increased promptly with application of PCPS.
