Hemodynamic response to high-volume hemofiltration in pediatric septic shock

High-volume hemofiltration (HVHF) has recently been recommended as an adjunctive therapy in pediatric septic shock; however, limited data on its therapeutic impact and the absence of defined response criteria remain concerns for its utilization. We aimed to report the hemodynamic response, patient characteristics, and their association with outcomes in children with refractory septic shock responding to HVHF.

We conducted a single-center cohort retrospective, descriptive, observational study of patients with septic shock receiving HVHF therapy. The progression of the vasoactive-inotropic score (VIS) from the start to 24 h of HVHF therapy was evaluated. The optimal timing and reduction of VIS were identified as predictors of survival, informing the most appropriate criteria for HVHF therapy responsiveness. Finally, the characteristics of patients who responded to HVHF were analyzed.

A total of 64 patients were included, with a median age of 26 months (interquartile range [IQR]: 7.5-82.0), all of whom were mechanically ventilated. The median VIS at inclusion was 411.2 (IQR: 168-770), and the median computed Septic Shock Score was 20.1 (IQR: 3.1-21.3). The median time from admission to HVHF initiation was 24 h (IQR: 12-48) and an ultrafiltrate rate of 80 mL/(kg·h) (IQR: 53-100). Overall, the survival rate was 27/64 (42.2%). The best response criterion was a >50% reduction in VIS after 12 h of HVHF therapy, with a survival rate of 65.2% (15/23) in responders vs. 32.4% (11/34) in nonresponders (P=0.010). Factors associated with response to HVHF included weight (odds ratio [OR]=1.04; 95% confidence interval [CI]: 1.00 to 1.08, P=0.040), age (OR=1.01; 95% CI: 1.00 to 1.02; P=0.280), and serum creatinine (OR=1.01; 95% CI: 1.00 to 1.02; P=0.046).

Our study indicated that a reduction of over 50% in the VIS after 12 h of HVHF therapy is the most reliable predictor of survival in children with refractory septic shock. These hypothesis-generating criteria may assist in early assessment of HVHF response.