Surgery for Acute Pancreatitis
What is pancreatic necrosis?
Severe pancreatitis causes death of parts of the pancreas. The injured and dying pancreas releases digestive enzymes in the pancreas, which causes extensive death of fatty tissue in the abdomen. As a consequence patients with severe pancreatitis have dead pancreatic tissue and also widespread death of fatty tissue around the pancreas. This dead pancreas tissue is called pancreatic necrosis and the dead fatty around the pancreas is called peripancreatic necrosis.
What happens to pancreatic necrosis?
In patients with severe pancreatitis, careful observation leads to improvement without an operation in about 60 to 70 percent of people. Thirty percent of patients will develop either progressive deterioration or infection in their necrosis and require surgery. The necrotic tissue is susceptible to infection and infections are very common in patients with severe pancreatitis.
Sterile and infected necrosis
When the dead pancreas is not infected, it is called sterile necrosis. When the dead pancreas is infected then it is called infected necrosis. More than 80% of deaths amongst patients with acute pancreatitis are caused by infection of the dead pancreatic tissue.The treatment of sterile and infected necrosis is complex and the patient may benefit from treatment in a specialty center that treat a high volume of these conditions.
Patients with sterile necrosis have dead pancreatic tissue, however there is no infection of the dead tissue. The recommended treatment for this group of patients is close observation in the hospital. Patients are placed on intravenous feeding and undergo serial examination with CT scans for early detection of infection.
We would consider surgery in patients with sterile necrosis under the following circumstances:
When is surgery done in patients with sterile necrosis
- Patients who fail to improve after about two to three weeks after the onset of their pancreatitis and continue to complain of severe in the abdomen.
- If there is concern that there might be infection in the necrosis
- Patients who continue to be critically ill after two weeks and require continued pulmonary and cardiac support
- Patients whose condition appears not be improving and or continue to deteriorate based on various measurements
The timing of surgery has been controversial. At USC our preference is to wait for about two weeks after onset of pancreatitis for surgery for sterile necrosis, as long as the patient does not have signs and symptoms of severe infection. The longer the wait the better the chance that the patient will have an adequate debridement (see below under Surgery for acute pancreatitis).
Usually after two weeks the dead pancreas tissue is demarcated (separated) from the live tissue and can be easily removed. Early surgery often leads to inadequate debridement of the necrosis since the demarcation has not occurred. Surgery for sterile necrosis is preferentially performed by laparoscopic techniques at our Center.
Infected necrosis occurs in patients who develop infection in areas of pancreatic and peripancreatic necrosis. This is a severe complication and requires aggressive treatment. More than 80% of deaths amongst patients with acute pancreatitis are caused by infection of the dead pancreatic tissue. Without aggressive surgical treatment to clear the infection, many patients do not survive the infection. Multiple surgeries may be required to completely clear the infection.
Patients with infected necrosis require emergent surgery. The treatment of infected necrosis is complex and these critically ill patients may benefit from treatment in a specialty center that treat a high volume of these conditions.
Surgery for acute pancreatitis
The surgery that is performed remove all the dead pancreas is called debridement of pancreatic necrosis. The term debridement means removal of all dead or necrotic tissue. In this surgery all dead or necrotic pancreas and any dead tissue outside of the pancreas is removed. Dead fatty tissue outside of the pancreas occurs in areas around the stomach and around the kidneys and sometimes the dead fat tissue may be found in the lower abdomen. The CT scan is very useful for planning surgery and all areas identified on CT scan of having necrotic or dead tissue are opened up and the dead areas are removed.
Laparoscopic Pancreatic Debridement
We have developed a specialized laparoscopic procedure for pancreatic debridement. In this procedure two to three small incisions are utilized for placements of laparoscopic instruments and a two-inch incision is utilized for placement of a hand-access device into the abdomen. The necrotic tissue in and the pancreas is accessed and completely removed. In addition to that, the necrotic tissue in other areas such as around the kidneys, colon, and pelvis may also be removed through laparoscopic techniques.
In our hands laparoscopic removal of the dead and necrotic pancreas is now the procedure of choice and open surgery is performed only in patients where at the time of the laparoscopic procedure we have concern that complete debridement has not been performed.
Long term outcome after surgical treatment for pancreatic necrosis
Many patients often require multiple surgeries to remove all the necrotic tissue. Patients often remain critically ill for a long period after their surgery until the infection subsides. The long-term complications after surgical treatment of acute pancreatitis are the following:
- Pancreatic Fistula: A pancreatic fistula is leakage of pancreatic juice in the abdomen from an injury to the pancreas. The majority of patients develop a pancreatic fistula after surgery. The fistula is from areas of raw surfaces on the pancreas left behind after removal of the entire dead pancreas. In the vast majority of patients, the fistula heals without any further surgery; however in some patients additional surgery may be required to remove the part of the pancreas that is contributing to the fistula.
- Pancreatic Pseudocyst
- Diabetes: Many patients develop diabetes after a severe attack of acute pancreatitis. Often the diabetes improves over time; however, some patients may have permanent diabetes if a large amount of the pancreas has been destroyed by the pancreatitis
- Chronic Pancreatitis