Assessment of Sublingual Microcirculation to Evaluate the Efficacy of Resuscitation Therapy in Septic Shock Patients: A cohort study.

Objectives: Determining the endpoint of resuscitation in septic shock is essential to enhance effectiveness, prevent over-resuscitation, and improve outcomes. We designed this study to investigate whether sublingual microcirculation monitoring can serve as an effective marker for assessing the efficacy of resuscitation therapy in septic shock.

Methods: A total of 72 septic shock patients were included in our final analysis, excluding those with heart function impairments, including sepsis-induced cardiomyopathy. Sublingual microcirculation parameters were measured at two time points: prior to resuscitation and 6 hours post-resuscitation. Additionally, the values of macrocirculatory parameters, blood gas analysis variables, and organ prognosis indicators were collected at multiple time points before and after resuscitation. Spearman correlation analysis was performed to assess the correlations among these variables. Furthermore, the ROC curve analysis method was employed to evaluate the predictive performance of sublingual microcirculation parameters and other relevant factors for patient prognosis. Finally we determined the optimal threshold of PPV6h by anchoring it to three key aspects: tissue oxygenation (Lac24h), organ dysfunction progression (△APACHE II3d and △SOFA3d), and long-term outcomes (Adverse Prognosis and 28-day mortality).

Results: Sublingual microcirculation variables post-resuscitation showed no significant correlation with conventional circulation variables. PPV6h had the highest predictive efficacy for 28-day prognosis, better than PcvO26h, the best predictor among conventional variables. The optimal PPV6h threshold (68.6%) was determined using three key criteria mentioned above. Patients meeting this threshold after resuscitation showed improved microcirculation (lower lactate levels and faster clearance), reduced organ dysfunction (lower APACHE II and SOFA scores, less need for CRRT), and better long-term outcomes (fewer vasoactive drugs, 28-day lower mortality).

Conclusions: Our study highlights the potential utility of sublingual microcirculation as an adjunctive tool for reflecting the effectiveness of resuscitation therapy and proposes that the PPV6h > 68.6% may serve as a target for early goal-directed therapy in future studies.