Establishment of a predictive model for outcomes in patients with severe acute pancreatitis by nucleated red blood cells combined with Ranson score and APACHE II score

Objective To explore a predictive model for outcomes of severe acute pancreatitis (SAP) patients. Methods A retrospective study was conducted of 102 SAP patients from January 1,2016 to April 30,2018 from Taizhou Hospital in this study. The participants were divided into survival group and death group according to the outcome of 90 days after admission,88 cases were in survival group including 57 males and 31 females, aged 55.5 (40.3-69.8) years; 14 cases were in death group including 5 males and 9 females, aged 63.0 (50.8-80.8) years. Clinical data and laboratory indicators were compared between the two groups. Statistical analyses were performed to compare categorical variables. Chi-square automatic interaction detector (CHAID) was used to construct the prediction model of SAP patients′ outcomes. The study cohort consisted of SAP patients from August 1st 2018 to July 1st 2019 were collected to validate the prediction model. Results (1)Statistical analyses were performed by chi square test and Mann-Whitney U test. There were statistically significant differences in the proportion of cardiovascular and cerebrovascular diseases, mechanical ventilation and septic shock, and also the Charlson complication index (CCI), the Ranson score and APACHEⅡscore(χ2=5.554, P=0.018; χ2=5.585,P=0.018;P=0.008;Z=-3.007,P=0.003;Z=-2.982, P=0.003; Z=-3.257, P=0.001), death group were higher than survival group. (2) The MPV, CRP, MCHC, pH, pCO2 and positive rates of NRBC were statistically different between survival group and death group(Z=-2.466,P=0.014;Z=-2.689,P=0.007;Z=-2.238,P=0.025;Z=-1.977,P=0.048;Z=-2.239, P=0.025;P=0.000).The NRBC-positive rate in the death group was higher than that in the survival group, while the other indexes were lower in the survival group.(3)The decision tree CHAID method obtains the prediction scheme: when it meets the Ranson score≤3, the SAP patients were judged to be alive; when it meets the Ranson score>3 and the NRBC in peripheral blood was negative, the SAP patients were judged to be alive; when it meets the Ranson score>3, the NRBC was positive and the APACHEⅡscore≤21, the SAP patients were judged to be alive; when it meets the Ranson score>3, NRBC was positive and APACHE Ⅱ>21, the SAP patients were adverse prognosis. (4) 50 SAP patients were collected in the validation group, with 43 actual survivors and 7 deaths. The accuracy rate of predicting the outcomes of SAP patients in validation group with the scheme was 94.0% (47/50). Conclusion The NRBC combined with Ranson score system and APACHE II score system can predict the outcomes of SAP patients. Key words: Acute disease; Pancreatitis; Erythroblasts; APACHE