How is the Clinical Efficacy of Extracorporeal Extraction Treatment Especially, Focused on the Hemodiafiltration, for Removal of Paraquat?

Yoon, Sung Chul; Tak, Woo Taek; Park, Young A; Lee, Jong An; Kim, Jong Wan

Abstract

PURPOSE: We tried to estimate the clinical efficacy of hemodiafiltration in the paraquat poisoning, as compared with that of other various extracorporeal extraction treatment.
METHODS
We prepared the fresh frozen plasma mixed with paraquat concentrated up to 30 mg/L. The experiment was designed to remove paraquat by use of various extracorporeal treatment, such as hemodialysis (HD), hemoperfusion (HP), hemofiltration (HF), hemodia-filtration (HDF), hemodiafiltration & hemoperfusion (HDFP), respectively. The efficacy was analyzed on the basis of counting extraction ratio, observing the decreasing concentration of paraquat with the lapse of time. Four pigs (Yorkshire) were prepared and poisoned by paraquat (40 mg/kg) intramuscularly. Two poisoned animals were assigned for hemoperfusion and hemodiafiltration respectively and other two were assigned for the control. We observed extraction ratio, decreasing concentration of paraquat in blood, remained amount of paraquat in major organs, in addition to pathologic change of major organs after sacrifying the animals.
RESULTS
The mean of extraction ratio is 0.84+/-0.27 in case of HP, 0.81+/-0.21 in HD, 0.74+/-0.40 in HDFP, 0.53+/-0.24 in HDF, 0.5+/-0.14 in HF. The extraction ratio of HP & HD & HDFP was significantly higher than that of HDF & HF (p<0.01). The extraction ratio was counted as the difference between the paraquat concentration of inlet and outlet was divided by the concentration of inlet. The slope of paraquat concentration undergoing extracorporeal treatment was the most acutely decreased in the case of HDFP, the less decreased in HP, and sequentially in HD, HDF and HF (the least) in the order of the decrease. The more decreased paraquat concentration in plasma was observed, the higher flow rate of dialysate of HDF was conducted. The mean of extraction ratio in animal study was 0.61 in HP and 0.36 in HDF. The blood concentration of paraquat was observed to be much lower in case of HP & HDF, as compared with the control animals. The remained concentration of paraquat in major organs, 7 hours later after being poisoned, was observed to be higher in the vascular structure like kidney and heart. However, it was observed to be lower in kidney, lung & muscle, when either of HDF and HP was conducted, than control. Especially, it was much lower in HP and much less pathologic change in HP. HDF is the less effective measure than HP, but is effective as a continuous treatment to make paraquat concentration to be lower as much as it possible.
CONCLUSION
The HDF is the effective measure to keep the blood paraquat level low, even though it is behind the HP in effectiveness.