Kinetics of Group IB and IIA Phospholipase A2 During Low‐Volume Continuous Hemodiafiltration in Severe Acute Pancreatitis

Continuous hemodiafiltration (CHDF) has been performed for the treatment of severe acute pancreatitis. Phospholipase A2 (PLA2) is one of the important mediators which exacerbate acute pancreatitis, but whether PLA2 can be removed by CHDF is unclear. In this study, the kinetics of group IB and group IIA PLA2 was examined at the first session of low-volume CHDF in eight patients with severe acute pancreatitis. CHDF was performed using polysulfone hemofilters (surface area: 0.7 m(2)) at a blood flow rate of 100 mL/min and a filtration and dialysate flow rate of 10 mL/min each. The plasma concentrations of group IB and IIA PLA2 before the start of CHDF were 47.4 +/- 52.0 microg/L and 352 +/- 390 microg/L, respectively, and did not change significantly. The clearances of group IB and IIA PLA2 achieved by the CHDF circuit 1 h after the start of CHDF were 20.7 +/- 11.6 mL/min and 16.7 +/- 4.4 mL/min, respectively, with both clearances decreasing significantly with time. The clearance of group IB PLA2 into the waste fluid tended to increase with time; however, the concentrations of group IIA PLA2 in the waste fluid were less than the measurable sensitivity. These results indicate that group IB PLA2 is adsorbed on the hemofilter membrane in preference to being removed into the waste fluid, while group IIA PLA2 is mainly removed by adsorption. However, low-volume CHDF is not effective at eliminating the group IB and IIA PLA2 plasma concentration.