Utility of core to skin temperature gradient and capillary refill time in determining prognosis for patients with septic shock: A prospective observational study

Introduction: Septic shock is characterized by heterogeneous microcirculatory alterations that may contribute to organ hypoperfusion and eventual death. The microcirculatory alteration can manifest in various clinical indicators, such as the core-to-skin temperature gradient (CSTG) and capillary refill time (CRT), reflecting the microcirculatory state. This prospective observational study explored the prognostic significance of the CSTG and CRT in septic shock. Methods: The study involved 54 patients over 18 months. The primary objective was to investigate the association between the CSTG measured using infrared thermography with an esophageal temperature probe and 8-day mortality in septic shock cases. Secondary objectives included comparing this gradient with CRT and assessing other parameters such as mean arterial pressure, arterial lactate values, urine output, vasopressor doses, and intensive care unit (ICU) length of stay. Results: The results indicated a meaningful correlation between the CSTG and 8-day mortality. The mean difference between CSTG was 1.21°C (0.65°C–1.77°C) higher in patients who died within 8 days of ICU admission than in those alive after 8 days of ICU admission. Notably, this temperature gradient demonstrated superior predictive capabilities compared to CRT, as at 6 h after admission, CRT of >4 s could predict 8-day mortality with a sensitivity of 25.6%. At the same time, CSTG of >7°C could predict 8-day mortality with a sensitivity of 87.2%. Conclusion: The CSTG is a robust predictor of 8-day mortality in septic shock with superior predictive capabilities compared to CRT.