3.4.7 Other outcome measures
Nineteen studies analyzed the clearance effect of serum amylase in the CRRT group and the control group, and the heterogeneity was large(I2>95%). There were respectively 9 and 15 studies compared the impact of CRRT group and control group on IL-6 and TNF-α clearance effect. In the same way, both outcomes have the large heterogeneity (I2>95%). We attempted to conduct a subgroup analysis of each study by age, population and the treatment time, but the results showed that there was great heterogeneity between groups, all of which exceeded 90%. Therefore, we considered that the main source of heterogeneity may was clinical heterogeneity. For this reason, we conducted a systematic evaluation of the above outcome indicators, the results showed that the application of CRRT was superior to the conventional treatment in reducing the level of inflammatory factors in patients. Among them, in terms of IL-6 clearance, all the studies after CRRT were controlled below 140, while 5 studies with conventional treatment were above 200. In terms of TNF-α clearance effect, 6 studies were reduced to less than 50 and 12 to less than 100 after CRRT treatment, while only 2 were reduced to less than 50 and 6 were reduced to less than 100 in the conventional group. The difference between the two groups was statistically significant(P<0.00001).
Similarly for serum amylase, 11 of the patients in the CRRT group had serum amylase levels below 200 after treatment, compared with only 1 in the conventional treatment group. In terms of safety, ALT levels were analyzed 11 studies, patients in the CRRT treatment group had AST over 40 in 6 studies and over 40 in 9 studies in the conventional group. The difference between the two groups was statistically significant(P<0.00001).