Patients with severe pancreatitis have complex conditions and a long course of illness. Treatment and prevention of malnutrition are issues that clinicians must pay attention to during the treatment of severe pancreatitis. In the implementation of nutritional support, it is necessary to choose the mode of nutritional support according to the advantages and disadvantages of enteral and parenteral nutritional support. The principle of choosing nutritional support method should not stimulate the exocrine secretion of the pancreas, but also achieve the purpose of nutritional support, and even achieve the role of nutritional pharmacology. In the process of treating severe pancreatitis, we feel that we can decide the mode of nutritional support for severe pancreatitis according to the following specific methods.
1. Not to pursue a certain type of nutritional support completely.
That is, we do not mechanically pursue total enteral nutrition (TEN), or total parenteral nutrition (TPN). In the early stage of nutrition support, doctors who advocate parenteral nutrition support emphasize total parenteral nutrition support; doctors who advocate enteral nutrition support also emphasize total enteral nutrition support. In some hospitals, enteral nutrition is administered by dietitians and parenteral nutrition is administered by physicians. This tends to lead to a single mode of nutritional support.
In fact, total enteral and total parenteral nutrition have their own advantages and disadvantages in the process of clinical nutrition support. Clinicians should decide whether to use enteral or parenteral nutrition or a combination of both in different proportions according to the different stages of severe pancreatitis and the changes of the disease. Parenteral nutrition can achieve the purpose of nutritional support without stimulating the exocrine secretion of the pancreas, and is a more ideal form of nutritional support in the early stage of severe pancreatitis. However, long-term use of parenteral nutrition can lead to biliary system cholestasis and liver damage. Sometimes the progressive jaundice makes the surgeon to abandon parenteral nutrition support. If enteral nutrition support is not successfully initiated at this time, a clinical dilemma is often created.
Recurring vena cava catheter infections are also a problem for clinicians. These vena cava infections cannot be resolved by external infection control measures alone. Analysis of the pathogenic organisms of intravenous catheter sepsis in surgically critically ill patients has revealed that the causative organisms are mostly of enteric origin. This is related to intestinal flora ectopic.
In patients with long-term parenteral nutrition, the intestinal mucosa is deprived of mucosal nutrients and the intestinal mucosa atrophies due to the long-term lack of intraluminal nutritional support mode, which leads to impaired intestinal barrier function. The intestinal bacteria continuously enter the bacteria through the damaged intestinal mucosal barrier, causing recurrent systemic infections. If the patient uses antibiotics for a long time, it leads to bacterial resistance. This makes the infection in patients with severe pancreatitis a more complicated problem. At this time, restoring enteral nutrition, especially enteral nutrition with micro-ecological immune nutrition, may be the only way. Since enteral nutrition conforms to normal physiology, it can really supply nutrient substrate from the portal system and meet the nutritional needs of intestinal mucosa, so enteral nutrition is an effective means to solve the infection and liver function damage combined with parenteral nutrition.
When implementing enteral nutrition, the special needs of intestinal mucosal epithelium and intestinal associated lymphoid tissue (GAL T) should be considered, and arginine, glutamine, polyunsaturated fatty acids and dietary fiber, and even intestinal beneficial bacteria should be added appropriately to achieve the purpose of micro-ecological immune nutrition.
Two issues must be noted in the implementation of enteral nutrition in patients with severe pancreatitis. One is to minimize the stimulation of exocrine secretion of the pancreas, i.e., to implement enteral nutrition through the duodenum at a distance. The enteral nutrition tube can be passed nasally through the pylorus with the aid of gastroscopy or under X-ray guidance, and the tip of the tube is placed in the distal part of the duodenal jugular, preferably in the high jejunum. Gastroscopy-assisted nasojejunal placement can be performed by push-in, trocar placement, and foreign body clamp. In addition, a special trans-enteral nutrition tube can be placed through the gastroscopic biopsy hole. However, it requires a special enteral nutrition tube, which is slightly more expensive and complicated to operate.
When the nasojejunal tube is placed by X-ray guide, the guide wire of the enteral nutrition tube can be replaced by the super-slip guide wire used for angiography. This makes it easier to adjust the strength of the super-slip guidewire to enter the pylorus under the instruction of the fluoroscope. After successful placement, the guidewire can be withdrawn more easily.
When severe pancreatitis is operated for various reasons, the problem of late nutritional support should be thought of, so a jejunostomy tube should be placed intraoperatively. The classic tunnel-embedded abdominal wall hanging tube jejunostomy method (Wechsler jejunostomy method) can be used, and the punctured jejunostomy method can also be used. Since severe pancreatitis has different degrees of malnutrition and low tissue healing ability, regardless of the method used, abdominal wall suspension should be performed to avoid artificial jejunostomy fistula. When choosing a tube, we should not choose too thick latex tube or myxomatous tube to avoid jejunostomy fistula or postoperative jejunostomy stenosis. Generally, a rubber tube of 10-14F can be chosen.
When administering enteral nutrition, start with a small amount at a uniform rate to avoid stimulation of the pancreas by nutrient reflux. The gastrointestinal decompression tube can be suctioned regularly to check whether there is any retention or regurgitation of enteral nutrition fluid. Since whole protein and fat have a strong exocrine stimulation on the pancreas, it is advisable to choose short peptide and low-fat formulas when selecting enteral nutrition products. In order to compensate for the energy deficit of low-fat, manufacturers may increase the proportion of carbohydrates in enteral nutrition formulas, which may cause or aggravate hyperglycemia. However, hyperglycemia can be corrected by subcutaneous injection of insulin, which does not pose a big problem to the clinic.
2. Emphasize the timely resumption of enteral nutrition
The so-called timely, that is, not to pursue premature implementation of enteral nutrition. In the field of trauma, especially burns, some studies have confirmed that early enteral nutrition can reduce patients’ hypermetabolism, reduce infection complications and mortality. Therefore, for many years, experts who are enthusiastic about enteral nutrition have advocated the early implementation of enteral nutrition support in trauma patients. This conclusion has been extended to the early enteral nutrition support in various diseases.
Through active implementation of enteral nutrition support in a large number of cases, we found that two prerequisites for successful implementation of enteral nutrition are that the patient’s intestinal function must be fully or partially restored, and there should be an appropriate amount of digestive fluid to complete the digestive function. If enteral nutrition can be successfully started, its effects are obvious, but it also comes with risks.
In the early stage of severe pancreatitis, it is often more costly to simply achieve the word “early”. In patients with severe pancreatitis, there are different degrees of intestinal dysfunction in the early stage. Forced implementation of enteral nutrition is not uncommon, but it is followed by retention and retention of nutrient fluid. As a result, the pancreatic gland is repeatedly stimulated and the pancreatic inflammation is difficult to subside as soon as possible, and the disease may persist. The exocrine function of the pancreas is damaged due to pancreatic inflammation, or the pancreatic fluid and bile are drained by surgery, or the intestinal fluid is lost due to pancreatic fistula and intestinal fistula, all of which can lead to digestive insufficiency. The enteral nutrition solution given is often difficult to be completely digested and absorbed, and this problem is even more serious if the enteral nutrition solution is of whole protein type. It can be said that the motor and digestive insufficiency of severe pancreatitis limits the premature implementation of enteral nutrition.
Due to the limitation of motor and digestive function, the implementation of enteral nutrition may result in symptoms such as vomiting and diarrhea. In addition to the discomfort and the aforementioned hazards, such symptoms may cause loss of nutritional substrates, resulting in inadequate supply of energy and protein. If total enteral nutrition is pursued at this time, it is difficult to achieve the purpose of preventing and correcting malnutrition, and even aggravate malnutrition as a result. In fact, similar phenomenon has been observed in other critically ill patients. Accordingly, it may be misunderstood that enteral nutrition is difficult to be implemented in severe pancreatitis, and it may also lead to the neglect of enteral nutrition for a long time after the failure of one early attempt of enteral nutrition. However, the problems caused by long-term parenteral nutrition make it difficult to carry out parenteral nutrition. This makes the clinical nutrition in a dilemma.
3. Combined use of enteral and parenteral nutrition and appropriate adjustment
The best way to prevent the above dilemma is to solve the supply of nutritional substrate through parenteral nutrition first. In the early stage of severe pancreatitis, enteral nutrition should be implemented carefully, and in the later stage, enteral nutrition should be implemented actively. When the intestinal function is partially restored, only partial enteral nutrition should be used to achieve the purpose of intraluminal nutrition and mucosal nutrition, and to treat and prevent the impairment of intestinal barrier function.
For this purpose, only 20% of the total energy supply should be provided through the intestine. Inadequate energy and protein supply can be supplemented by parenteral route. As the total amount of sugar, fat emulsion and amino acids supplied through the intestine is reduced, the osmotic pressure of the parenteral nutrition solution is also reduced accordingly, and through the all-in-one nutrition preparation technology, the osmotic pressure of the nutrition solution is almost close to that of ordinary liquid, so it is not necessary to infuse through the vena cava, which fundamentally solves the problem of catheter sepsis. The appropriate amount of enteral nutrition also promotes the improvement of intestinal motility, digestion and absorption function, which is conducive to the eventual complete restoration of enteral nutrition. Therefore, for patients with severe pancreatitis without excessive complications, the general mode of nutritional support should be total parenteral nutrition, enteral nutrition + parenteral nutrition and total enteral nutrition, until the complete resumption of oral diet.
It is important to emphasize that this model should not be implemented in a consistent manner in the nutritional support of severe pancreatitis. When the disease changes, the nutritional support should be adjusted accordingly. Patients with severe pancreatitis often develop abdominal abscesses or retroperitoneal infections, intra-abdominal hemorrhage, extra-pancreatic and extra-intestinal fistulas, and even multiple organ dysfunction (MOD) during the course of the disease. These complications can affect intestinal function to varying degrees. In this case, an objective analysis of the patient’s intestinal function should be made to decide whether to stop, partially or completely implement enteral nutrition support.
It is common to see that enteral nutrition is used without paying attention to changes in the condition, thus aggravating the condition. The opposite phenomenon can also be seen, because of the fear of stimulating the pancreas, in patients with severe pancreatitis, the prolonged use of parenteral nutrition with various antibiotics leads to infection, especially multi-drug resistant bacteria to the point of no drug available. In the aforementioned patients, the mere resumption of enteral nutrition may have resulted in complete control and eventual elimination of the infection.
In conclusion, nutritional support for patients with severe pancreatitis is a very important part of their comprehensive treatment process. In the process of nutritional support, neither pure total enteral and total parenteral nutrition nor the evolution of total parenteral, parenteral + enteral and total enteral nutrition is required.