DATA COLLECTION: A systematic search was performed using the following databases: Medline, EMBASE, CINAHL, and Cochrane from January 1990 till December 2022. Comparative studies of TPE in severe sepsis were selected. Adult and pediatric data were analyzed separately.
DATA SYNTHESIS: Eight randomized control trials and 6 observational studies (n = 50,142 patients) were included. Centrifugal TPE was the most common modality (209/280, 74.6% adults and 952/1026, 92.7% children). Every TPE study utilized different volume exchanges. Most TPE sessions (1173/1306, 89.8%) employed fresh frozen plasma (FFP) as replacement fluid and heparin as anticoagulant. Adults with severe sepsis supported with TPE using FFP had lower mortality (risk ratio, RR: 0.64 [95% confidence interval, CI: 0.49, 0.84]) compared to those who did not. In contrast, TPE was associated with increased mortality in septic children without thrombocytopenia-associated multiorgan failure (RR: 2.23, 95% CI: 1.93, 2.57). There was no difference in outcomes in patients supported with centrifugal and membrane TPE. In both populations, patients supported on TPE as a continuous regime had poorer outcome.
CONCLUSION: Current evidence indicates that TPE is a potential adjunct therapy in adults with severe sepsis but not in children.
METHODS: We measured plasma and post-filter levels of IL-6, TNF-alpha, IL-8, IL-1 beta, RANTES, IL-10, IFN-gamma and IFN-alpha in both study groups. We also measured cytokine levels in the ultrafiltrate and calculated sieving coefficients and clearances.
RESULTS: By 72 hours of treatment, IL-6 had decreased during both treatments (p = 0.009 and 0.005 respectively). In contrast, IL-10 had decreased with CVVH-Std (p = 0.03) but not CVVH-HCO (p = 0.135). None of the other cytokines showed changes over time. There were also no significant between group differences in plasma levels for each cytokine over the 72-hour treatment period. For all cytokines combined, however, the median sieving coefficient was higher for CVVH-HCO (0.31 vs. 0.16; p = 0.042) as was the mass removal rate by ultrafiltration (p = 0.027). While overall combined cytokine levels had fallen to 62.2% of baseline at 72 hours for CVVH-HCO (p<0.0001) and to 75.9% of baseline with CVVH-Std (p = 0.008) there were no between group differences.
CONCLUSIONS: CVVH-HCO achieved greater combined sieving coefficient and mass removal rate by ultrafiltration for a group of key cytokines than CVVH-Std. However, this effect did not differentially lower their plasma level over the first 72 hours. Our study does not support the use of CVVH-HCO to lower cytokines in critically ill patients with AKI.