Indications for total parenteral nutrition in the hospitalized patient: a prospective review of evolving practice.

The indications for initiating total parenteral nutrition (TPN) were prospectively evaluated in 100 consecutive patients at a tertiary referral hospital with a long-standing Nutritional Support Service to illustrate the reasons why the parenteral route was chosen at this unique institution in terms of patient population. Sixty male and 40 female patients, average age 59 +/- 17 years (range 22-86 years), were classified a priori as to the underlying reasons for initiation of TPN. The study was conducted by a Nutrition Support Service at this hospital without pediatric, trauma, or burn services specializing in the care of patients with diabetes mellitus. Of the 100 patients, 63% were from the surgical service; 24% had diabetes mellitus. Their mean weight (118 +/- 29% of ideal), body mass index (25 +/- 6 kg/m(2)), and serum albumin (2.8 +/- 0.7 g/dL) indicated a reasonable body composition with a moderate systemic inflammatory response. Six patients received preoperative TPN for an average of 5 +/- 3 days with a variety of diagnoses including malignancy, Crohn's disease, bowel obstruction, and gastrointestinal bleeding. The underlying reasons for initiating nutritional support were related to three factors that largely determine the need for involuntary feeding: preexisting protein calorie malnutrition, actual or anticipated semistarvation for a prolonged period, and the presence of a systemic inflammatory response. The choice of TPN was based on anticipated or proven intolerance to full enteral feeding. The duration of time before initiation of TPN postoperatively was 6 +/- 5 days, which reflects our policy that initially well-nourished patients who are experiencing a systemic inflammatory response should not undergo more than 5 to 7 days of inadequate feeding. The duration of TPN overall was 11 +/- 10 days, which primarily illustrates the dramatic reduction in length of hospital stay that has occurred throughout the health care system and the willingness to provide TPN in alternative settings including transitional care units, rehabilitation hospitals, and for short-term care, the patient's home. The most common specific reasons identified for initiating TPN rather than enteral nutrition were ileus (25%), an underlying acid-base or electrolyte/mineral disorder (13%) requiring correction, and the convenience of TPN because a central venous catheter was in place (12%). The usual indication for nutritional support at this tertiary referral and specialty hospital was actual or impending protein calorie malnutrition. TPN was chosen for a variety of reasons related to actual or anticipated tolerance to enteral feeding. This audit demonstrates that our TPN practice has evolved in relation to time of initiation and duration of feeding, which reflect a clearer appreciation of the risks and benefits of TPN.

Experience with enteral nutrition in a hospital population of acutely ill patients.

Enteral feeding has unique metabolic and immune advantages. This article describes the successful use of enteral nutrition, alone or in combination with parenteral feeding, in a tertiary-care hospital. Study participants were 89 patients who received enteral feeding during a 6-month period. These critically ill patients (ranging in age from 55 to 71 years) had severity of illness levels of 7 to 25 according to the Acute Physiologic and Chronic Health Evaluation (APACHE II) system and lengths of hospital stay from 27 to 73 days. Mortality was as high as 50% in patients with liver disease (nonmalignant), 35% in patients with cardiothoracic and vascular diseases, and 17% in patients with cancer and other diseases. Despite the severity of illness, patients met their energy and protein intake goals through enteral or combined feeding with total parenteral nutrition. Serial weights (ie, obtained weekly) and serum albumin concentrations did not improve during hospitalization. Complications related to enteral feeding were minimal (< 17% incidence). Differences were noted between survivors and nonsurvivors: nonsurvivors had lower serum albumin concentrations at the time of admission, had longer hospitalizations, and required total parenteral nutrition for more days than the survivors. Nonetheless, even with extremely sick patients, provision of enteral nutrition can be successful using the administration techniques we describe. Enteral nutrition could best be provided by beginning at a slow rate (10 c3/hour), inserting the feeding tube past the pylorus, and feeding according to sensible energy goals (25 kcal/kg of body weight), and using elemental then polymeric formulas.

A proposed revision of current ICD-9-CM malnutrition code definitions.

Protein-energy malnutrition (PEM) is as common today in adult medical and surgical patients as it was when it was first identified more than 25 years ago. Under the current diagnosis-related group (DRG) payment system, malnutrition is considered a comorbidity or complicating condition. Thus, the identification and coding of malnutrition through the use of the International Classification of Diseases, ninth edition, Clinical Modification (ICD-9-CM) malnutrition codes can potentially change a patient's DRG and subsequently increase the amount of reimbursement a hospital receives. Unfortunately, the definitions for the current ICD-9-CM malnutrition diagnosis codes were developed principally in relation to clinical syndromes of primary PEM seen in pediatric age groups in less developed countries, rather than in relation to syndromes seen in hospitalized adult patients in industrialized societies. This discrepancy often leads to confusion and inconsistency when institutions attempt to code adult patients for malnutrition. Furthermore, inaccurate coding can result in inadequate reimbursement or rejection of a claim. Clearly, a separate description of the different forms of PEM seen in adults is needed not only for optimal application of nutrition support therapies but also for accurate medical records, quality assurance procedures, and reimbursement purposes. On the basis of 20 years of experience providing nutrition support to hospitalized adult patients, this article presents a schema developed at the Deaconess Hospital (Boston,Mass) that attempts to better define adult PEM using the ICD-9-CM malnutrition codes. The purpose of this article is to foster discussion and ultimately promote general agreement about a definition of adult PEM.

Fish-oil-containing diet and platelet aggregation.

Current research suggests that a diet high in fish oil may be useful for immunomodulation in hospitalized patients. However, one of the side effects of fish oil is a prolongation of the bleeding time, specifically by reducing platelet aggregability. Although this effect might be beneficial for patients with cardiovascular disease, it would be a potential concern in certain critically ill patients. To address this concern, we conducted a prospective study of platelet aggregation in 16 surgical patients who were randomly assigned to receive either a diet containing 16.5 g of fish oil in 1500 ml (Impact) or usual care (standard enteral formulas devoid of fish oil). Feeding was successfully accomplished in the patient group receiving a diet that provided approximately 14.2 g of fish oil/day for 1 wk without significantly affecting platelet aggregability. Thus, it appears that, over the short term, this dose of fish oil does not alter platelet function in hospitalized surgical patients.

Effect of a fish oil structured lipid-based diet on prostaglandin release from mononuclear cells in cancer patients after surgery.

BACKGROUND: The authors compared the effect on eicosanoid production (prostaglandin E2 [PGE2], 6-keto PGF 1 alpha, and thromboxane B2) from peripheral blood mononuclear cells (PBMC) of feeding an enteral diet containing a fish oil/medium-chain triglyceride structured lipid (FOSL-HN) vs an isonitrogenous, isocaloric formula (O-HN) in patients undergoing major abdominal surgery for upper gastrointestinal malignancies. A previous study, which used the same formulas and experimental design, suggested improved renal and liver function as well as a reduced number of gastrointestinal and infectious complications with the use of fish oil structured lipids. This study sought to investigate the potential mechanism for these effects by assessing eicosanoid production from PBMC with the two diets. METHODS: This prospective, blinded, randomized trial was conducted in 20 patients who were jejunally fed either FOSL-HN or O-HN for 7 days. Serum chemistries, hematology, urinalysis, gastrointestinal complications, liver and renal function, and eicosanoid production from isolated PBMC, either unstimulated or stimulated with endotoxin, were measured at endotoxin baseline and on day 7. Comparisons were made in 10 and 8 evaluable patients based a priori on the ability to reach a tube feeding rate of > 40 mL/h. RESULTS: Patients receiving FOSL-HN experienced no untoward side effects compared with patients given O-HN and demonstrated the same general trend toward improved hepatic, renal and immune function found in the previous study. There was a significant reduction in PGE2 (p < .03) and 6-keto PGF 1 alpha (p < .01) production from PBMC with endotoxin stimulation in patients receiving FOSL-HN. CONCLUSIONS: The results of early enteral feeding with FOSL-HN after surgery in this follow-up study provide further support to claims of safety, tolerance, and improved physiologic function. There was an associated reduction in eicosanoid production from PBMCs, which is presumed to be the principal mechanism for these effects.

Glutamine content of whole proteins: implications for enteral formulas.

In two recent clinical trials in surgical patients, supplementation of total parenteral nutrition with daily doses of 12 or 20 g of glutamine resulted in a diminished loss of free glutamine in skeletal muscle tissue. Studies in animals exploring the use of both enteral and parenteral glutamine supplementation suggest that glutamine may be an essential nutrient in the maintenance of gut structure and function during critical illness. These findings have led to heightened interest in the glutamine content of enteral formulas. This article describes a method for estimating the glutamine content of whole-protein enteral formulas. The average amount of glutamine in selected, whole-protein formulas ranges from a minimum of 3.55 g/4200 kJ to a maximum of 5.15 g/4200 kJ. Although it is still too early to define the safest and most effective dose of glutamine, there are two points regarding glutamine supplementation that clearly merit further investigation: no clinical trials have been conducted to assess the potential benefits of glutamine supplementation of an enteral diet or to assess the effects of using diets containing protein-bound glutamine rather than free glutamine.

Randomized phase I/II trial of a macrophage-specific immunomodulator (PGG-glucan) in high-risk surgical patients.

OBJECTIVE: The safety and efficacy of PGG-glucan in surgical patients at high risk for postoperative infection who underwent major thoracic or abdominal surgery were determined. SUMMARY BACKGROUND DATA: Recent studies have reported a 25% to 27% infectious complication rate in patients undergoing major surgery with an average cost per infected patient of $12,000. The efficacy of PGG-glucan pretreatment in prevention of sepsis has been demonstrated in rodent models for gram-negative and gram-positive bacterial and yeast infections. In vitro studies have demonstrated enhanced microbial killing by monocytes and neutrophils in healthy volunteers after PGG-glucan administration. Thus, PGG-glucan may play a role in decreasing the infectious complication rate in patients undergoing major surgery. METHODS: A double-blind, placebo-controlled randomized study was performed in 34 high-risk patients undergoing major abdominal or thoracic surgery. RESULTS: There were no adverse drug experiences associated with PGG-glucan infusion. Patients who received PGG-glucan had significantly fewer infectious complications (3.4 infections per infected patient vs. 1.4 infections per infected patient, p = 0.05), decreased intravenous antibiotic requirement (10.3 days vs. 0.4 days, p = 0.04) and shorter intensive care unit length of stay (3.3 days vs. 0.1 days, p = 0.03). CONCLUSIONS: PGG-glucan is safe and appears to be effective in the further reduction of the morbidity and cost of major surgery.

Tolerance to enteral tube feeding diets in hypoalbuminemic critically ill, geriatric patients.

Tolerance of elemental (for example, Peptamen [PEP]) or free amino acid (for example, Vivonex TEN [VIV]) tube feeding diets is controversial, especially in the critically ill patient who is hypoalbuminemic. A prospective, randomized trial was conducted to compare differences between feeding PEP (n = 8) or VIV (n = 8) in critically ill, elderly (average age of 66 years) patients. Diets were administered through nasogastric or postpyloric feeding tubes. Eleven patients had diseases of the gastrointestinal tract; all underwent surgical treatment. Patients were fed each diet at full strength, beginning with 20 to 30 milliliters per hour and advancing by 10 to 20 milliliters every day until goal rate was reached, usually on day 4. Assessment was made for ability to comply with rate of tube feeding ordered, compliance with caloric goal and tolerance (as evidenced by abdominal discomfort and diarrhea). Diarrhea was qualitatively defined as more than three stools per day and then quantitatively as the mean number of stools daily. There were no significant differences between the two groups in terms of compliance with prescribed tube feeding order or caloric goal or the presence of diarrhea and abdominal discomfort. There was a significant difference between the two groups in terms of the actual number of stools per day (PEP equals 1.38 versus VIV equals 2.25, p less than 0.02). Serum albumin concentrations upon initiation of the diets were 2.3 grams per deciliter in both groups. We conclude that tolerance to the two diets were similar because it was possible to feed enterally either PEP or VIV in critically ill, hypoalbuminemic patients (serum albumin concentrations of less than 2.5 grams per deciliter) successfully, irrespective of diet. Although there were more stools in the VIV group, this did not reduce compliance with the goals.

Early enteral feeding in postsurgical cancer patients. Fish oil structured lipid-based polymeric formula versus a standard polymeric formula.

OBJECTIVES: The authors compared the safety, gastrointestinal tolerance, and clinical efficacy of feeding an enteral diet containing a fish oil/medium-chain triglyceride structured lipid (FOSL-HN) versus an isonitrogenous, isocaloric formula (O-HN) in patients undergoing major abdominal surgery for upper gastrointestinal malignancies. SUMMARY BACKGROUND DATA: Previous studies suggest that feeding with n-3 fatty acids from fish oil can alter eicosanoid and cytokine production, yielding an improved immunocompetence and a reduced inflammatory response to injury. The use of n-3 fatty acids as a structured lipid can improve long-chain fatty acid absorption. METHODS: This prospective, blinded, randomized trial was conducted in 50 adult patients who were jejunally fed either FOSL-HN or O-HN for 7 days. Serum chemistries, hematology, urinalysis, gastrointestinal complications, liver and renal function, plasma and erythrocyte fatty acid analysis, urinary prostaglandins, and outcome parameters were measured at baseline and on day 7. Comparisons were made in 18 and 17 evaluable patients based a priori on the ability to reach a tube feeding rate of 40 mL/hour. RESULTS: Patients receiving FOSL-HN experienced no untoward side effects, significant incorporation of eicosapentaenoic acid into plasma and erythrocyte phospholipids, and a 50% decline in the total number of gastrointestinal complications and infections compared with patients given O-HN. The data strongly suggest improved liver and renal function during the postoperative period in the FOSL-HN group. CONCLUSION: Early enteral feeding with FOSL-HN was safe and well tolerated. Results suggest that the use of such a formula during the postoperative period may reduce the number of infections and gastrointestinal complications per patient, as well as improve renal and liver function through modulation of urinary prostaglandin levels. Additional clinical trials to fully quantify clinical benefits and optimize nutritional support with FOSL-HN should be undertaken.