Role of arterial blood glucose and interstitial fluid glucose difference in evaluating microcirculation and clinical prognosis of patients with septic shock: a prospective observational study.

Background: Microcirculation abnormality in septic shock is closely associated with organ dysfunction and mortality rate. It was hypothesized that the arterial blood glucose and interstitial fluid (ISF) glucose difference (G_A-I) as a marker for assessing the microcirculation status can effectively evaluate the severity of microcirculation disturbance in patients with septic shock.

Methods: The present observational study enrolled patients with septic shock admitted to and treated in the intensive care unit (ICU) of a tertiary teaching hospital. The parameters reflecting organ and tissue perfusion, including lactic acid (Lac), skin mottling score, capillary refill time (CRT), venous-to-arterial carbon dioxide difference (Pv-aCO₂), urine volume, central venous oxygen saturation (ScvO₂) and G_A-I of each enrolled patient were recorded at the time of enrollment (H0), H2, H4, H6, and H8. With ICU mortality as the primary outcome measure, the ICU mortality rate at any G_A-I interval was analyzed.

Results: A total of 43 septic shock patients were included, with median sequential organ failure assessment (SOFA) scores of 10.5 (6-16), and median Acute Physiology and Chronic Health Evaluation (APACHAE) II scores of 25.7 (9-40), of whom 18 died during ICU stay. The G_A-I levels were negative correlation with CRT (r = 0.369, P < 0.001), Lac (r = -0.269, P < 0.001), skin mottling score (r=-0.223, P < 0.001), and were positively associated with urine volume (r = 0.135, P < 0.05). The ICU mortality rate of patients with septic shock presenting G_A-I ≤ 0.30 mmol/L and ≥ 2.14 mmol/L was significantly higher than that of patients with G_A-I at 0.30-2.14 mmol/L [65.2% vs. 15.0%, odds ratio (OR) = 10.625, 95% confidence interval (CI): 2.355-47.503].

Conclusion: G_A-I was correlated with microcirculation parameters, and with differences in survival. Future studies are needed to further explore the potential impact of G_A-I on microcirculation and clinical prognosis of septic shock, and the bedside monitoring of G_A-I may be beneficial for clinicians to identify high-risk patients.