Study Comparing Capillary Refill Time with Lactate and Correlation with Resuscitation Outcome

BACKGROUND: Shock is a critical condition of circulatory failure and results in cellular and tissue hypoxia. Early identification and treatment are crucial for improving patient outcomes. While parameters like lactate levels are commonly used to monitor shock, capillary refill time (CRT) has reemerged as a valuable marker for assessing peripheral perfusion. This study compared CRT with lactate to evaluate its correlation with resuscitation outcomes in septic shock patients. OBJECTIVES: The primary objective: To assess the association of initial CRT or lactate levels with Intensive Care Unit (ICU) mortality in patients admitted with septic shock. Secondary objectives. To evaluate the change in CRT and lactate at 3 hours and 24 hours concerning mortality, organ function and ICU Length of stay (LOS) after 24 hours of resuscitation. MATERIALS AND METHODS: A prospective observational study was conducted from October 2022 to June 2024 in the medical ICU of a tertiary care hospital in Kochi, Kerala. Sixty adult patients with septic shock were enrolled. Key indicators such as CRT, lactate levels, and the Sequential Organ Failure Assessment (SOFA) scores were measured at admission, after 3 hours, and after 24 hours of resuscitation, as per standard ICU protocol. Patients with Chronic Kidney Disease Stage 5, Decompensated Chronic Liver Disease, readmission to ICU, and Do not resuscitate status were excluded. The primary outcomes included ICU mortality, and the secondary outcomes included changes in organ function, as measured by SOFA scores and ICU LOS. Statistical analysis was performed using SPSS version 20. RESULTS: Prolonged CRT at admission was observed in 88.3% of patients, and abnormal lactate levels were present in 95%. The median SOFA score was 7. The mortality rate for patients with prolonged CRT was 15% and 14% for those with abnormal lactate levels. There was no statistically significant relationship between the initial CRT or lactate and death in ICU. Improvement in CRT after 24 hours significantly correlated with lower mortality (p = 0.009), while changes in lactate levels at 24 hours were associated with both increased mortality (p < 0.001) and worsening organ dysfunction (p < 0.001). CONCLUSION: Initial CRT and lactate were abnormal in most subjects but showed no significant association with ICU mortality (15% for prolonged CRT, 14% for abnormal lactate). Both parameters appeared to be comparable predictors of mortality. Patients with both abnormal CRT and lactate at admission had longer ICU LOS. No significant relationship was found between combined CRT and lactate levels with mortality or organ function. However, CRT improvement at 24 hours was associated with reduced mortality, while non-improvement indicated higher mortality but not organ failure. Changes in lactate at 24 hours correlated with ICU mortality and SOFA score changes. Changes in CRT or lactate at 3 hours did not predict mortality, organ function, or ICU LOS.