Selection of acute blood purification therapy according to severity score and blood lactic acid value in patients with septic shock

AIM: As an alternative method for acute blood purification therapy, continuous venovenous hemodiafiltration (CVVHDF) has been reported as an effective clinical treatment for critically ill patients, but the optimal column for performing CVVHDF remains controversial. PATIENTS AND METHODS: We used direct hemoperfusion using a polymyxin B-immobilized fiber column (DHP-PMX) to treat 88 patients with septic shock. To determine the optimal acute blood purification therapy, we subsequently divided the patients into three groups: the first group underwent CVVHDF using a polymethylmethacrylate membrane hemofilter (PMMA) after undergoing DHP-PMX (28 cases), the second group underwent CVVHDF using a polyacrylonitrile membrane hemofilter (PAN) after undergoing DHP-PMX (26 cases), and the third group did not undergo CVVHDF after undergoing DHP-PMX (34 cases). RESULTS: The overall survival rate was 54.5%, and patient outcome was significantly related to the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the sepsis-related organ failure assessment (SOFA) score, and the blood lactic acid value before treatment (all P<0.0001). Only the PMMA-CVVHDF group showed a better outcome (survival rate of 78.6%) compared with the other groups (P = 0.0190). In addition, only the PMMA-CVVHDF group showed a significant improvement in the blood lactic acid level on day 3 (P = 0.0011). CONCLUSION: Our study suggests that the PMX column might be effective during the early phase of septic shock, before a high level of lactic acid is present. Furthermore, a PMMA column might be the most useful column for performing CVVHDF after DHP-PMX treatment, as suggested by the blood lactic acid value.