The aim of this study is to establish the influence of early administration of a bolus of intravascular fluid in patients with a diagnosis of acute pancreatitis on the course and outcome of disease.

This is a prospective, randomized, controlled clinical trial of standard versus enhanced hydration in patients diagnosed with acute pancreatitis within the first hour of diagnosis.

Patients admitted in the Emergency Department with the clinical suspicion of acute pancreatitis will be processed through the history, physical examination and laboratory findings. The diagnosis of acute pancreatitis is established by the presence of 2 of the 3 following criteria: typical abdominal pain, serum amylase and / or lipase greater than three times the upper limit of normal, and characteristic findings from abdominal imaging. Patients will be informed about the study protocol and the possible risks and adverse events, after which they will be asked to accept participation in the study. Acceptance of participation will be confirmed by signed informed consent.

After acceptance patients will be randomized by computer-generated sequences of random numbers in the two groups Group one (1) will receive a bolus of fluid 20 ml / kg of Ringer's solution for infusion within one hour of the diagnosis and the group two (2) will receive a bolus of fluid 40 ml / kg of Ringer's solution for infusion within one hour of the diagnosis. All patients who have the diagnosis of acute pancreatitis, but did not agree to participate in research or have some other exclusion criteria will be treated according to the standards of good clinical practice and the recommendations of the current clinical guidelines for the treatment of acute pancreatitis. Exclusion criteria beside refusal to sign informed consent are: age less than 18 years, pregnancy, patients with physical signs of heart failure, previously known congestive heart failure (NYHA III - IV) and severe kidney disease more than one month before the diagnosis of acute pancreatitis (defined as severe reduction in eGFR less than 30 ml/min/1.73 m2). Patients who develop acute renal failure as a result of acute pancreatitis will be involved in research .

Given the importance of early hydration in patients with acute pancreatitis and the lack of clearly defined dose of administered fluid in the current literature, aim of this study was to determine the influence of the size of the dose bolus of intravascular fluid after the diagnosis of acute pancreatitis in the further course and outcome of disease.

The study will be conducted in the Emergency Department, Clinical Hospital Centre, Rijeka.

Inclusion Criteria:

All patients with diagnosis of acute pancreatitis.

Exclusion Criteria:

1. Refusal to sign informed consent
2. Age less than 18 years
3. Pregnancy
4. Patients with physical signs of heart failure,
5. Previously known congestive heart failure ( NYHA III - IV )
6. Severe kidney disease more than one month before the diagnosis of acute pancreatitis (defined as severe reduction in eGFR less than 30 ml/min/1.73 m2) . Patients who develop acute renal failure as a result of acute pancreatitis will be involved in research .