Injuries to the pancreas

External injury (Fig. 55.23)

Presentation and management

The most frequent presentation of blunt pancreatic trauma is epigastric pain which may be minor at first, with the progres­sive development of more severe pain due to the sequelae of leakage of pancreatic fluid into the surrounding tissues. A rise in pancreatic amylase occurs in 90 per cent of cases. A CT scan of the pancreas or ultrasound scan will delineate the damage that has occurred to the pancreas. Persisting abdomi­nal pain with signs of peritonitis require careful assessment of the patient, and support by intravenous fluids and a nil oral regime should be instituted. Immediate operation is contra-indicated because the bruising associated with the retroperi­toneal damage will prevent clear visualisation of the pancreas. It is preferable to manage conservatively, investigate with ultrasound and, once the damage is ascertained, undertake appropriate action. Operation is only indicated if there is disruption of the main pancreatic duct; almost all other patients will resolve with conservative management unless duct stricturing develops leading to recurrent episodes of pancreatitis, in which case the appropriate treatment is resection of the tail of the pancreas up to the site of duct disruption. If the damage is purely confined to the head of the pancreas simple drainage is normally effective; should this fail, however, then a pancreatoduodenectomy may be necessary.

A pancreatic pseudocyst may develop (Fig. 55.24). If the main duct is intact, the cyst should be drained percutaneously. It is now rarely necessary to undertake a cystgastrostomy (Fig. 55.25). If the cyst develops in the presence of complete disruption of the pancreas, there is no alternative but to undertake a distal resection.

Prognosis

The most common cause of death in the immediate period is bleeding, but once the acute phase has passed the mortality and morbidity should be minimal with a complete return to normal activity. The mortality rate of penetrating injury to the pancreas with associated injuries to the surrounding viscera approaches 50 per cent.

latrogenic injury

This can occur in four ways.

  Injury to the tail of the pancreas during splenectomy resulting in a pancreatic fistula.

  Injury to the accessory pancreatic duct (Santorini) which is the main duct in 7 per cent of patients during Billroth II gastrectomy. A pancreatogram performed by cannulating the duct at the time of discovery of such an injury will demonstrate whether it is safe to ligate and divide the duct. If no alternative drainage duct can be demonstrated then the duct should be reanastomosed to the duodenum.

  Attempts at enucleation of islet cell tumours of the pan­creas can result in fistulae.

  Duodenal or ampullary bleeding following sphinctero­tomy. This injury may require duodenotomy to control the bleeding.

Pancreatic fistula

This usually follows operative trauma to the gland, or may occur as a complication of acute or chronic pancreatitis. Management is to define the site of the fistula, the epithelial structure to which it communicates (e.g. external to skin or internal to bowel), and to correct metabolic and electrolyte disturbances. The danger of a pancreatic fistula is that there is digestion of surrounding structures by activated pancreatic enzymes causing local damage, perforation, bleeding and digestion of the skin. Immediate control of the fistula can be obtained by a nil by mouth regime, the use of octreotide and adequate drainage of the fistula with protection of the skin. Investigation of the cause of the fistula is required and, usually, once the cause is determined appropriate remedies can be introduced. Frequently the cause is related to obstruc­tion within the pancreatic duct which can be overcome by the insertion of a stent or catheter endoscopically into the pancreatic duct, and waiting for closure of the fistula while supporting the patient by a conservative regime with parenteral nutritional support and good nursing. As a principle, in the management of any fistula, the underlying cause for the fistula must be treated before closure will be effective.