Cecal
ligation and
puncture (CLP) is the gold standard model for studying
septic shock which is characterized by
hypotension and hyporeactivity to
vasoconstrictors. However, approximately 30% of CLP animals do not exhibit cardiovascular changes, requiring more replicates due to the high variability of the model. Therefore,
biomarkers enabling the early prediction of cardiovascular collapse in
sepsis would greatly benefit
sepsis nonclinical studies, refining experimental models and improving clinical translation. Thus, this study aimed to test whether the early increase in
lactate levels could predict
hypotension and hyporesponsiveness to
vasoconstrictors in a rat model of
sepsis. Male and female Wistar rats were subjected to CLP or
sham procedure. Tail blood
lactate was measured 6, 12 and 24 hours after surgery. Then, inflammatory, biochemical, and hemodynamic parameters were evaluated. Rats subjected to CLP developed
hypotension, hyporesponsiveness to
vasoconstrictors, an intense inflammatory process, and increased plasma markers of organ dysfunction. By employing ROC curve analysis, we have established that a
lactate value of 2.45 mmol/L can accurately discriminate between a rat exhibiting a normal vasoconstrictive response and a vasoplegic rat with 84% accuracy (AUC: 0.84, CI: 0.67-1.00). The sensitivity, which is the ability to identify the true positive rats, was 75% (CI: 41 - 95), and the true negative rate was 81% (CI: 57 - 93). Therefore, early measurement of
lactate levels in
sepsis could serve as a valuable
biomarker for distinguishing vasoplegic rats from those exhibiting normal vasoconstrictive responses.