Effect of high-dose intravenous vitamin C on point-of-care blood glucose level in septic patients: a retrospective, single-center, observational case series.

INTRODUCTION

High-dose vitamin C is an essential adjunctive drug for sepsis treatment. This study aimed to determine if high-dose vitamin C could lead to erroneous point-of-care glucose testing results.

METHODS AND MATERIALS

This retrospective, single-center, observational case series involved septic patients treated with high-dose vitamin C. We monitored their paired point-of-care glucose and laboratory glucose levels for statistical analysis. The glucose oxidase-peroxidase colorimetric method and hexokinase spectrophotometric method were applied for point-of-care glucose and laboratory glucose monitoring, respectively. Parkes Consensus Error Grid Analysis was used to assess the clinical influence of paired blood glucose values. Subgroup analyses were conducted to explore the effect of different vitamin C dosages and various renal function levels on point-of-care glucose readings.

RESULTS

During a 3-year period, 82 eligible septic patients who accepted at least three days of high-dose vitamin C treatment were included in this study. Compliance with ISO15197:2013 criteria was met in 30 (36.59%) paired values, a proportion considerably lower than the minimum criteria for accuracy. Subgroup analysis showed that worse renal function or higher vitamin C dosage could lead to greater bias in point-of-care glucose readings; however, these inaccuracies rarely represented a clinical risk.

CONCLUSIONS

High-dose intravenous ascorbate acid infusion may interfere with point-of-care glucose testing results. Thus, laboratory glucose measurements are recommended for more accurate results. Nonetheless, the inaccuracies magnitude of point-of-care glucose readings does not represent a significant clinical risk when physicians alter clinical action based on these results.