Cerebral oximetry values in dialyzed surgical patients: a comparison between hemodialysis and peritoneal dialysis

Abstract

Background: Cerebral tissue regional oxygen saturation (rSO₂) through near-infrared spectroscopy (NIRS) is a method for non-invasive monitoring of cerebral tissue oxygenation. However, nowadays there is limited information on the level of cerebral tissue oxygenation in dialyzed end-stage renal disease (ESRD) surgical patients. The aim of this observational study was to evaluate the baseline cerebral rSO₂ values, to compare values between hemodialysis (HD) and peritoneal dialysis (PD) patients and identify risk factors that could predict cerebral tissue oxygenation in these patients. Patients/Methods: Thirty-two ESRD patients (≥18 years old), scheduled to undergo elective minor or major surgery, were enrolled. Patients were allocated in two groups according to dialysis modality. Twenty-three patients were treated with HD and nine were treated with PD. Demographic and clinical characteristics, comorbidities and arterial hemoglobin oxygen saturation (SpO₂) of the study population were recorded. Results: Patients who were treated with HD had significant lower baseline rSO₂ values compared with PD patients [median, 50% (28–63) vs. 63% (45–69), p = 0.002]. Hierarchical linear regression model analysis showed that preoperative Hb and SpO₂ were positive predictive variables (B = 0.353, p = 0.01 and B = 0.375, p = 0.009, respectively) for rSO₂. Moreover, dialysis modality was independent predictor for baseline rSO₂. The modality of dialysis remained an independent predictor for rSO₂ after controlling for the other significant variables (B = 0.291, p = 0.032) and PD was associated with higher baseline values of rSO₂. Conclusion: In conclusion, ESRD surgical patients undergoing PD treatment appear to have significantly higher baseline cerebral tissue saturation values compared with HD.

• Cerebral oximetry values
• end-stage renal disease
• hemodialysis
• peritoneal dialysis