Imaging is indicated during the initial presentation if:

the diagnosis of acute pancreatitis is uncertain
there is abdominal distension and tenderness, fever >102 F (38,9 C), or leukocytosis
there is a Ranson score > 3 or APACHE score > 8
there is no improvement after 72 hours of conservative medical therapy
there has been an acute change in status: fever, pain, or shockCT is recommended as a delayed assessment tool in the following situations:

acute change in status
to determine therapeutic response after surgery or interventional radiologic procedure
before discharge in patients with severe acute pancreatitisAbdominal CT should not be performed before the first 12 hours of onset of symptoms as early CT (<12 hours) may result in equivocal or normal findings. CT findings can be classified into the following categories for easy recall:

Intrapancreatic – diffuse or segmental enlargement, edema, gas bubbles, pancreatic pseudocysts and phlegmons/abscesses (which present 4 to 6 wks after initial onset)
Peripancreatic / extrapancreatic – irregular pancreatic outline, obliterated peripancreatic fat, retroperitoneal edema, fluid in the lessar sac, fluid in the left anterior pararenal space
Locoregional – Gerotas fascia sign (thickening of inflamed Gerotas fascia, which becomes visible), pancreatic ascites, pleural effusion (seen on basal cuts of the pleural cavity), adynamic ileus, etc.The principal value of CT imaging to the treating clinician is the capacity to identify devitalised areas of the pancreas which have become necrotic due to ischaemia. Pancreatic necrosis can be reliably identified by intravenous contrast-enhanced CT imaging, and is of value if infection occurs and surgical or percutaneous debridement is indicated.
In addition, meperidine has a short half-life and repeated doses can lead to accumulation of the metabolite normeperidine, which causes neuromuscular side effects and, rarely, seizures. Bowel rest
In the management of acute pancreatitis, the treatment is to stop feeding the patient, giving them nothing by mouth, giving intravenous fluids to prevent dehydration, and sufficient pain control. As the pancreas is stimulated to secrete enzymes by the presence of food in the stomach, having no food pass through the system allows the pancreas to rest. Approximately 20% of patients have a relapse of pain during acute pancreatitis. Approximately 75% of relapses occur within 48 hours of oral refeeding.The incidence of relapse after oral refeeding may be reduced by post-pyloric enteral rather than parenteral feeding prior to oral refeeding. IMRIE scoring is also useful. Nutritional support
Recently, there has been a shift in the management paradigm from total parenteral nutrition (TPN) to early, post-pyloric enteral feeding (in which a feeding tube is endoscopically or radiographically introduced to the third portion of the duodenum). The advantage of enteral feeding is that it is more physiological, prevents gut mucosal atrophy, and is free from the side effects of TPN (such as fungemia). The additional advantages of post-pyloric feeding are the inverse relationship of pancreatic exocrine secretions and distance of nutrient delivery from the pylorus, as well as reduced risk of aspiration.