• Length of stay at the primary hospital [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Length of stay at the primary hospital and ICU. Number of days from initial operation to primary hospital discharge.
• Concentration of Lactate (mM), Pyruvate (microM), Glycerol (microM), Glucose (mM) in microdialysate [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Concentration of Lactate, Pyruvate, Glycerol, Glucose in microdialysate in relation to patients with or without anastomosis leakage
• Concentration of inflammatory markers in microdialysate [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Concentration of inflammatory markers in microdialysate in relation to patients with or without anastomosis leakage
• Concentration of inflammatory markers in serum [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Concentration of inflammatory markers in serum in relation to patients with or without anastomosis leakage
• Patient-reported quality of life questionnaire - total score assessed by the Abdominal surgery Impact scale by summing subscores [ Time Frame: From inclusion to 90-days after surgery ]
  Total score - Abdominal surgery Impact scale. The summative scores for the scale range from 18 to 126, with higher scores indicating better quality of life
• Patient-reported quality of life questionnaire - subgroup score Physical limitations assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Physical limitations - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating better physical ability
• Patient-reported quality of life questionnaire - subgroup score Functional impairment assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Functional impairment - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating better functional ability
• Patient-reported quality of life questionnaire - subgroup score Pain assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Pain - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating more pain
• Patient-reported quality of life questionnaire - subgroup score Visceral Function assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Visceral Function - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating more Visceral dysfunction
• Patient-reported quality of life questionnaire - subgroup score Sleep assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Sleep - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating more sleep dysfunction
• Patient-reported quality of life questionnaire - subgroup score Psychological function assessed by the Abdominal surgery Impact scale [ Time Frame: From inclusion to 90-days after surgery ]
  Subgroup score Psychological function - Abdominal surgery Impact scale. The summative scores for the scale range from 3 to 18, with higher scores indicating more psychological dysfunction
• Patient-reported pain questionnaire - total score assessed by the McGill Pain Questionnaire-2 (SF-MPQ-2) [ Time Frame: From inclusion to 90-days after surgery ]
  Total score - McGill Pain Questionnaire-2 (SF-MPQ-2). Subgroup score Psychological function - Abdominal surgery Impact scale. The summative scores ranging from 0 to 45, with higher score indicating more pain
• Expenses (Euros) per patient used during total hospital stay [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Number of Euros used in patient undergoing pancreaticoduodenectomy With or without microdialysis catheter
• Daily assessement of microdialysis catheter malfunction during admission at hospital, at an average of 10 days after surgery [ Time Frame: From surgery end to discharge from primary hospital, at an average of 10 days after surgery ]
  Number of catheter which are not functioning
• Risk factors of postoperative pancreatic fistula at discharge from hospital, at an average 10 days after surgery [ Time Frame: From surgery end to discharge from primary hospital at hospital, at an average of 10 days after surgery ]
  Numbers of risk factors of postoperative pancreatic fistula in relation to patients with or without anastomosis leakage
• Risk factors of postoperative pancreatic fistula at 30 days after surgery [ Time Frame: From surgery end to 30 days after surgery ]
  Numbers of risk factors of postoperative pancreatic fistula in relation to patients with or without anastomosis leakage
• Risk factors of postoperative pancreatic fistula at 90 days after surgery [ Time Frame: From surgery end to 90 days after surgery ]
  Numbers of risk factors of postoperative pancreatic fistula in relation to patients with or without anastomosis leakage

• Time before postoperative fistula is diagnosed (hours) [ Time Frame: End of surgery to 30 days postoperative ]
  Hours from end of surgery to diagnosis of postoperative pancreatic fistula
• Total quantity (μg/mg) of vasoactive medications at discharge at an average of 10 days after surgery [ Time Frame: From surgery end to discharge from primary hospital at an average of 10 days after surgery ]
  Amount of vasoactive medication during surgery and postoperatively until discharge from the hospital where the surgery was performed.
• Number of patients with Pancreatic Fistula [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Number of patients with Pancreatic Fistula
• Number of patients with Biliary Fistula [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Number of patients with Biliary Fistula
• Number of patients with gastroenteric Fistula [ Time Frame: 30 days after surgery - postoperative day 30 ]
  Number of patients with gastroenteric Fistula
• Daily measurements during hospital admission of pancreatic amylase (U/L) and bilirubin (µmol/L ) concentrations in drainage fluid and in serum, at an average og 10 days after surgery [ Time Frame: From surgery end to discharge from primary hospital at an average of 10 days after surgery ]
  Pancreatic amylase and bilirubin concentrations in drainage fluid and in serum
• Postoperative complications [ Time Frame: From inclusion to 90-days after surgery ]
  Number of patients with postoperative complications during total hospital stay
• Fluid Balance (ml) during hospital admission at an average of 10 days after surgery [ Time Frame: From anesthesia start to discharge from primary hospital at an average of 10 days after surgery ]
  Diuresis and amount of fluid given i.v. during surgery and postoperatively until discharge from the primary hospital
• Number of patients discharged to home/self care at an average of 10 days after surgery [ Time Frame: At discharge at an average of 10 days after surgery ]
  Patient's discharge disposition - number of patients Discharged to home/self care
• Number of patients discharged to home but with home health service at an average of 10 days [ Time Frame: At discharge at an average of 10 days after surgery ]
  Patient's discharge disposition - number of patients Discharged to home but with home health service
• Number of patients discharged/transferred to nursing home at an average of 10 days [ Time Frame: At discharge at an average of 10 days after surgery ]
  Patient's discharge disposition - number of patients Discharged/transferred to nursing home
• Number of patients discharged/transferred to an inpatient rehabilitation facility at an average of 10 days [ Time Frame: At discharge at an average of 10 days after surgery ]
  Discharged to an inpatient rehabilitation facility
• Number of patients expired at an average of 10 days [ Time Frame: At discharge at an average of 10 days after surgery ]
  Patient's discharge disposition - expired

Anastomotic leakage after pancreaticoduodenectomy is a feared complication with substantial mortality and morbidity. Treatment of a postoperative pancreatic fistula can be difficult and management may range from a simple observation with or without percutaneous drainage, to the urgent need for reoperation and management of abdominal sepsis with organ failure and prolonged intensive care. To diagnose a pancreatic fistula may have a delay of several days. The risk of death and severe morbidity raises considerable from a biochemical pancreatic fistula compared to the most serious form, a grade C. Also, the cost of managing a patient with a fistula is 1.3-6 times more than a patient with no complications after PD.

Microdialysis is a promising tool in patients who undergoes pancreaticoduodenectomy for early detection of postoperative pancreatic fistula development. The technique may reveal an fistula before severe symptoms occur and before the complication gives the patient serious and life-threatening symptoms. Earlier intervention of the postoperative pancreatic fistula may lead to better prognosis, less reoperations and interventions and shorter stay at the ICU/hospital. By monitoring intraperitoneal metabolites (glycerol, lactate, pyruvate and glucose) close to the pancreaticojejunostomy, signs of a leakage may be discovered in few hours, thereby make it possible for early intervention and prevent developement of serious progression of morbidity. The investigators want to perform a randomized study where half of the patients will receive a microdialysis catheter implanted close to the pancreaticoduodenal anastomosis before closure of the abdomen. At certain timepoints postoperatively microdialysate will be analyzed for glycerol, lactate, pyruvate and glucose and the data will be used in the decisionmaking of diagnosing a pancreatic anastomosis leakage in addition to standard management. The other half of the patients will not receive a microdialysis catheter and the decisionmaking will only be based on standard management (ie. inflammation markers in blood samples, amylase in drainage fluid).

• Pancreatic Cancer
• Pancreatic Neoplasms
• Biliary Tract Cancer
• Duodenal Cancer
• Pancreatic Fistula

• Active Comparator: Patient with microdialysis
  Intervention group - Patients will receive an intraperitoneal microdialysis catheter and will be monitored consecutively by microdialysis. The surgeon is familiar with the current microdialysis results at any time during the study period. The surgeon may intervene based on traditional symptoms and signs plus predetermined values of the microdialysis results.
  Intervention: Procedure: Surgical og radiological intervention, antibiotics
• No Intervention: Patient without microdialysis
  The control group - The patients will not receive a microdialysis catheter. The patients are monitored according to current standards of care and the surgeon may intervene based only on traditional symptoms and signs.

Inclusion Criteria:

• Patients must be scheduled for a pancreaticoduodenectomy
• Subject must be ≥ 18 years
• Able to give written signed informed consent
• Investigator's assessment that the patient is able to understand, comply and follow the instructions needed to successfully participate in this trial

Exclusion Criteria:

• Allergic to Voluven® (Fresenius Kabi AS, Halden, Norway) and contrast given during CT scan
• Another study interfering with current study
• Pregnant