Risk Factors Analysis And Prediction Of Clinically Relevant Postoperative Pancreatic Fistula After Laparoscopic Pancreatoduodenectomy

Objective: Recently,plenty of literatures were published to analyze the risk factors of pancreatic fistula after pancreatoduodenectomy(PD),however,the study of PF prediction for laparoscopic pancreatoduodenectomy(LPD)was rare.The aim of our study was to investigate the independent risk factors and predictors of clinically relevant postoperative pancreatic fistula(CR-POPF)after LPD by analyzed pre-,intra-and postoperative variables,with the measurement of body fat distribution and remnant pancreas parameters estimated by preoperative computed tomography(CT).Methods: The clinical records of 388 consecutive patients who underwent LPD between July 2014 and December 2018 at the Tongji Hospital,Tongji Medical College,Huazhong Scientific and Technological University were reviewed retrospectively.Patients were divided into PF group and NO-PF group,clinical data between two groups concerning patient characteristics(gender,age,comorbidity(diabetes mellitus,high blood pressure,cardiovascular disease),pancreatitis history,abdominal surgery history,preoperative biliary drainage and pathological diagnosis;preoperative laboratory data(admission bilirubin,preoperative bilirubin,hemoglobin,serum albumin,alanine transaminase,?-glutamyltranspeptidase,CA19-9,CA125),preoperative CT parameters(total fat area(TFA),visceral fat area(VFA),subcutaneous fat area(SFA),abdominal wall thickness,intra-abdominal fat thickness,main pancreatic duct width,pancreas gland thickness);intraoperative parameters(operative time,blood loss,transfusion,pancreatic texture assessed by surgeons,type of pancreatoenterostomies)and postoperative laboratory datalaboratory data(white blood cell count of postoperative day 1(WBC POD1),white blood cell count of postoperative day 3(WBC POD3),WBC(POD3-POD1),platelet count of postoperative day1(Plt POD1),platelet count of postoperative day 3(Plt POD3),plt(POD3-POD1),serum albumin of postoperative day 1(Alb POD1),serum albumin of postoperative day 3(Alb POD3),Alb(POD3-POD1))were compared.Univariate analysis and multivariate logistic regression analysis were performed to investigate the independent risk factors,To evaluate the ability of the predictive models of POPF,the area of receiver operating characteristic curve(ROC)was performed.Results: A total of 388 patients with LPD were included in this study.The study population was comprised of 198 men and 190 women,with a median age of 57 years(50-63).Overall morbidity was 19.8%(77/388)in the entire group with a overall mortality of 2.3%(9/388).The CR-POPF occurred in 31patients(8.0%),including grade B PF in 28(7.2%)and grade C PF in 3(0.8%)patients,biochemical fistula occurred in 42 patients(10.8%).Bile leakage,postoperative hemorrhage,intra-abdominal abscess,sepsis,delayed gastric emptying,cardiac complications,pulmonary complications occurred in Bile leakage occurred in 7 cases(1.8%),postoperative hemorrhage in 28 cases(7.2%),intra-abdominal abscess in 36 cases(9.3%),sepsis in 7 cases(1.8%),delayed gastric emptying in 39 cases(10.1%),cardiac complications in 6cases(1.5%),pulmonary complications in 16 cases(4.1%).6(1.5%)patients required reoperation.The median postoperative hospital stay was 15 days(13-19).Patients were divided into PF group(31 cases)and NO-PF group(357 cases)according to the CR-POPF,univariate analysis and multivariate analysis and ROC analysis of risk factors of POPF as following:1.Univariate analysis Univariate analysis showed that non-pancreatic cancer diseases(p=0.028),operative time>320min(p=0.002),soft pancreatic texture (p<0.001),TFA>221cm~2(p<0.001),SFA>121cm~2(p=0.015),VFA>82cm~2(p<0.001),main pancreatic duct width<3mm(p<0.001)and Alb(POD3-POD1)<-3.1g/L(p=0.011)were significantly associated with a higher risk of CR-POPF.2.Multivariate analysis The multivariate analysis showed that VFA>82cm~2(OR=11.088;p=0.029),main pancreatic duct width<3mm(OR=7.701;p=0.001),soft pancreatic texture(OR=12.543;p=0.022),operative time>320min(OR=6.061;p<0.001)were the independent risk factors of the CR-POPF.3.ROC analysis of predictive models The ROC analysis of risk factors revealed the pancreatic texture was the strongest single-predictor(AUC=0.854),the best 2-predictors model(pancreatic texture and pancreatic duct width)resulted in a AUC of 0.904,the combination of pancreatic duct width and pancreatic texture and operative time was best 3-predictors model(AUC=0.932),and the predictive ability of the combination of 4 risk factors reached 0.940.In addition,this study revealed that VFA>82cm~2 and main pancreatic duct width<3mm,TFA>221cm~2 and the non-pancreatic cancer diseases were significantly associated with a soft pancreas,the texture of the pancreas can be evaluated simply by VFA,TFA and pancreatic duct width before operation.Conclusions:This study revealed that VFA>82cm~2,main pancreatic duct width<3mm,soft pancreatic texture,operative time>320min were the independent risk factors of the CR-POPF,with a strong predictive ability for the occurrence of postoperative pancreatic fistula.In addition,obesity was closely related to soft pancreas,abdominal fat area measured by CT before operation can preliminarily evaluate the texture of pancreas.The preoperative CT is of great significance in the prediction of CR-POPF after LPD.