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Updated: Mar 17, 2026

Measurement of Tissue Oxygenation Using Near-Infrared Spectroscopy in Patients Undergoing Hemodialysis
Published on: October 2, 2020
Moderator's view: Higher serum bicarbonate in dialysis patients is protective
1Harold Simmons Center for Chronic Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California Irvine School of Medicine, 101 City Drive South, City Tower, Orange, CA 92868-3217, USA Los Angeles Biomedical Research Institute at Harbor-UCLA, Torrance, CA, USA Veterans Affairs Long Beach Healthcare System, Long Beach, CA, USA.
Higher serum bicarbonate levels in dialysis patients may not increase mortality risk. This association could be due to undernutrition, not a direct biological link, suggesting careful management of bicarbonate levels is prudent.
Area of Science:
- Nephrology
- Clinical Chemistry
Background:
- Observational studies suggest a link between high serum bicarbonate and mortality in dialysis patients.
- This association may be confounded by factors like dietary protein intake and nutritional status.
Purpose of the Study:
- To critically evaluate the association between serum bicarbonate levels and mortality risk in dialysis patients.
- To explore potential confounding factors and the biological plausibility of the observed association.
Main Methods:
- Review of existing observational studies and physiological principles of acid-base balance in hemodialysis.
- Analysis of the contribution of dialysate components to serum bicarbonate levels.
Main Results:
- The observed association may be an epiphenomenon, potentially driven by undernutrition, a known predictor of mortality.
- The metabolic contribution of acetate from acid concentrate to the patient's bicarbonate pool is likely negligible.
Conclusions:
- The link between high serum bicarbonate and mortality in dialysis patients requires cautious interpretation due to potential confounding.
- It is advisable to maintain serum bicarbonate levels within a moderate range, avoiding extremes in dialysis patients.
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