Enteral or parenteral nutrition? Pro-enteral

Correction of patient results for Beckman Coulter LX-20 assays affected by interference due to hemoglobin, bilirubin or lipids: a practical approach

The influence of interference by hemolysis, icterus and lipemia on the results of routine chemistries may lead to wrong interpretations. On Synchron LX-20 instruments (Beckman Coulter) serum or plasma indices can be used as reliable semi-quantitative measures of the magnitude of such interference. In an article recently published in this journal, we presented the results of a multicenter study carried out in Dutch hospitals in which we determined cutoff indices for analytes above which analytically significant interference exists. Clinically significant interference cutoff indices were also derived for these analytes. In this article, we describe the handling of patient samples with clinically significant interference by hemolysis, icterus or lipemia. We investigated several possible approaches for correction of the result: dilution of the interference; mathematical correction in the case of hemolysis; treatment with ferrocyanide to destroy bilirubin; and removal of lipids in lipemic patient samples. We concluded, that mathematical correction of potassium or lactate dehydrogenase results in hemolytic samples can only be carried out if intravascular hemolysis is ruled out. Hemoglobin quantification in serial patient samples, combined with measurement of haptoglobin, represents a useful tool to rule out in vivo hemolysis. We derived an algorithm for this situation. We do not simply recommend mathematical correction, unless it is clinically acceptable. We present formulas for potassium and lactate dehydrogenase: corrected potassium=measured potassium-(hemolytic index increment x 0.14); corrected lactate dehydrogenase=measured lactate dehydrogenase-(hemolytic index increment x 75). The dilution studies indicated that dilution is only applicable for bilirubin, C-reactive protein and iron. The results of treatment with ferrocyanide were poor, and we do not recommend this method. Removal of lipids using high-speed centrifugation or LipoClear (StatSpin Inc.), a non-toxic and non-ionic polymer, is a very effective approach, although C-reactive protein, creatine kinase-MB (CK-MB) and cholesterol cannot be removed using LipoClear. For all interferants (hemoglobin, bilirubin, lipids), relatively simple algorithms are derived that can easily be implemented in the clinical laboratory.

Jejunal feeding, even when instituted late, improves outcomes in patients with severe pancreatitis and peritonitis

This study assessed the feasibility and effectiveness of jejunal feeding (JF) after surgery due to secondary peritonitis or failed conservative therapy of severe pancreatitis. Of 60 patients, 30 were randomly assigned to receive postoperative JF and the remaining 30 constituted the control group. Acute Physiology and Chronic Health Evaluation II, nutritional intake, systemic inflammatory response syndrome, and outcomes were measured. Patients in JF group received the daily mean of 1294.6 (362.6) kcal including 830.6 (372.7.0) kcal enterally, versus 472.8 (155.8) kcal daily in the control group (P < 0.0001). There were fewer complications in the JF patients, with no significant difference; length of stay in the intensive care unit and in the hospital did not differ. The frequency of systemic inflammatory response syndrome was similar in both groups, but outcomes differed. The first surgical intervention resulted in 3.3% of relaparotomies in JF patients, caused by unresolved peritonitis, versus 26.7% in the control subjects (P = 0.03). Recovery of bowel transit took significantly less time in the JF patients (mean: 54.6 h versus 76.8 h in control subjects, P = 0.01). JF resulted in 3.3% mortality as opposed to 23.3% in the control group (P = 0.05). In conclusion, JF is feasible and effective in postoperative treatment of patients due to secondary peritonitis or severe pancreatitis. Improved bowel and peritoneal function could be the main impact of JF.

Enteral versus parenteral nutrition: a pragmatic study

Controversy persists as to the optimal means of providing adjuvant nutritional support. The aim of this study was to compare enteral nutrition (EN) and parenteral nutrition (TPN) in terms of adequacy of nutritional intake, septic and nonseptic morbidity, and mortality. This was a prospective pragmatic study, whereby the route of delivery of nutritional support was determined by the attending clinician's assessment of gastrointestinal function. Patients considered to have inadequate gastrointestinal function were given TPN (group 1), while those deemed to have a functioning gastrointestinal tract received EN (group 2). Patients in whom there was reasonable doubt as to the adequacy of intestinal function were randomized to receive either TPN (group 3) or EN (group 4). The trial setting was a large district general hospital with a dedicated nutrition team. A total of 562 patients were included in the study (331 males; median age 67 y). Gastrointestinal function on entry into the study was considered inadequate in 267 patients who were given TPN (group 1) and adequate in 231 whom received EN (group 2). There was clinical uncertainty about the adequacy of gut function in 64 patients (11.4%) who were randomized to receive either TPN (group 3, 32 patients) or EN (group 4, 32 patients). The incidence of inadequate nutritional intake was significantly higher in group 4 compared with group 3 (78.1% versus 25%, P < 0.001). Complications related to the delivery system and other feed-related morbidity were significantly more frequent in both EN groups compared with the respective TPN groups. EN was associated with a higher overall mortality in both nonrandomized and randomized patients. There were no significant differences observed in the incidences of septic morbidity between patients receiving TPN and those given EN. EN is associated with a higher incidence of inadequate nutritional intake, complications related to the delivery system, and other feed-related morbidity than TPN. There is no evidence from this study to support a difference between the two modalities in terms of septic morbidity. Patients in whom there is reasonable doubt as to the adequacy of gastrointestinal function should be fed by the parenteral route.

The impact of oral feeding on the severity of acute pancreatitis

BACKGROUND

In the management of acute pancreatitis, oral feeding is prohibited and either enteral or parenteral feeding is commenced for the patients in an effort to not increase the secretion of the pancreatic enzymes.

PURPOSE

This study was undertaken in an attempt to determine the impact of oral feeding on the severity of acute pancreatitis and to compare this impact with that of parenteral feeding.

MATERIALS AND METHODS

Twenty-four female Sprague-Dawley rats were divided into two groups. In both groups, acute pancreatitis was induced by ligation of the main biliopancreatic duct. The rats in group I were fed orally and the rats in group II were fed parenterally. The rats were sacrificed at 48 hours, and blood samples were obtained from the heart upon exposure of the abdominal and thoracic cavities. The pancreas and the left lung were removed for histopathological examination. The levels of lactic dehydrogenase (LDH), serum glutamic oxaloacetic transaminase (SGOT), glucose, calcium and blood urea nitrogen, base deficit, partial oxygen pressure, leukocyte count, and hematocrit level among Ranson criteria and the level of amylase were measured. The pancreas and the lung were examined under a light microscope.

RESULTS

The levels of LDH, SGOT, and calcium for the rats in group I were significantly higher when compared with the rats in group II (P <0.05). Similarly, the levels of amylase for the rats in group I were found to be higher when compared with the rats in group II, but the difference was not significant. Inflammatory changes observed in the pancreas were less severe whereas inflammatory changes observed in the lung were more severe for the rats in group I when compared with the rats in group II.

CONCLUSION

The blood levels of the enzymes were adversely affected for the rats fed orally. In contrast, inflammatory changes observed in the pancreas were more severe for the rats fed parenterally. The study suggests that certain hormones released from the duodenum upon stimulation by oral nutrient intake lessens the severity of pancreatitis through protective effects on the pancreas, whereas the elevated levels of the enzymes cause endothelial damage resulting in destruction in distant organs such as the lung.

Nutritional care of pancreatitis and its complications

This article reviews the current literary data on the role of conservative supportive treatment for acute pancreatitis, with special emphasis on parenteral and enteral nutrition. Despite the fact that the indications for both methods have been discussed, defined and widely accepted in recent years, enteral nutrition is currently the focus of recent clinical investigations for use in acute pancreatitis.