An in-line digestive cartridge increases enteral fat and vitamin absorption in a porcine model of short bowel syndrome

BACKGROUND & AIMS

Short bowel syndrome (SBS) occurs after intestinal loss resulting in parenteral nutrition dependence and micronutrient deficiencies, which may lead to life-limiting complications. ALC-078 is a cartridge containing immobilized lipase that connects in-line with enteral feeding sets and digests fats in enteral nutrition (EN). In this study, we evaluate the efficacy of ALC-078 to improve fat and nutrient absorption in a porcine SBS model.

METHODS

Fifteen male Yorkshire piglets were assessed. Animals were randomized to no intestinal resection (n = 5), 75% resection (n = 5), or 75% resection + ALC-078 (n = 5). After recovery, animals were treated for 14 days. Piglets received 60% of nutrition from continuous EN and 40% from chow. The degree of fat malabsorption was determined by the coefficient of fat absorption (CFA) following a 72-h stool collection. Body weight, fat-soluble vitamins, and nutritional markers were assessed.

RESULTS

Adverse events were similar across the three groups (P = 1.00). ALC-078-treated animals had similar weight gain compared to resected piglets. Resected animals had a lower CFA compared to unresected controls (79.3% vs. 95.2%, P = 0.01) while there was no significant difference in the ALC-078 animals (87.1% vs. 95.2%, P = 0.19). Between Study Days 1 and 15, ALC-078 animals had increased concentrations of vitamin D (12.2 vs. 8.7 ng/mL, P = 0.0006), and vitamin E (4.3 vs. 2.5 mg/L, P = 0.03). These markers did not significantly change in untreated resected animals.

CONCLUSION

ALC-078 increases the absorption of fat-soluble vitamins and may improve fat malabsorption. Future studies should determine whether ALC-078 can reduce PN dependence and if these findings translate to human patients with SBS.

Mechanisms for the effects of fish oil lipid emulsions in the management of parenteral nutrition-associated liver disease

Parenteral nutrition (PN) can be life saving for infants unable to adequately absorb enteral nutrients due to intestinal failure from inadequate bowel length or function. However, long-term PN carries significant morbidity and mortality, with 30 to 60% of patients developing progressive liver dysfunction. The etiology of PN-associated liver disease (PNALD) is poorly understood, however the involvement of lipid emulsions in its pathogenesis has been clearly established, with new emphasis emerging on the role of omega-6 polyunsaturated fatty acids and omega-3 polyunsaturated fatty acids. Recent studies evaluating the use of parenteral fish oil lipid emulsions instead of soybean oil lipid emulsions have demonstrated marked improvements in cholestasis, morbidity, and mortality in patients with PNALD treated with fish oil. This review provides an overview of the role of lipid emulsions in the pathogenesis of PNALD and the proposed mechanisms by which parenteral fish oil lipid emulsions may be exerting their beneficial effects.

Fish oil prevents essential fatty acid deficiency and enhances growth: clinical and biochemical implications

Fish oil, a rich source of omega-3 fatty acids, has never been used as the sole source of lipid in clinical practice for fear of development of essential fatty acid deficiency, as it lacks the believed requisite levels of linoleic acid, an omega-6 fatty acid. The objectives of this study were to establish biochemical standards for fish oil as the sole fat and to test the hypothesis that fish oil contains adequate amounts of omega-6 fatty acids to prevent essential fatty acid deficiency. Forty mice were divided into 2 groups that were either pair fed or allowed to eat ad libitum. In each group, 4 subgroups of 5 mice were fed 1%, 5%, and 10% fish oil diets by weight or a control soybean diet for 9 weeks. Blood was collected at 4 time points, and fatty acid analysis was performed. Food intake and weight status were monitored. All groups but the pair-fed 1% fish oil group gained weight, and the 5% fish oil group showed the highest caloric efficiency in both pair-fed and ad libitum groups. Fatty acid profiles for the 1% fish oil group displayed clear essential fatty acid deficiency, 5% fish oil appeared marginal, and 10% and soybean oil diets were found to prevent essential fatty acid deficiency. Fish oil enhances growth through higher caloric efficiency. We established a total omega-6 fatty acid requirement of between 0.30% and 0.56% of dietary energy, approximately half of the conventionally believed 1% as linoleic acid. This can presumably be attributed to the fact that fish oil contains not only a small amount of linoleic acid, but also arachidonic acid, which has greater efficiency to meet omega-6 fatty acid requirements.

Aminosyn PF or trophamine: which provides more protection from cholestasis associated with total parenteral nutrition?

Cholestasis often occurs in infants on total parenteral nutrition (TPN) for long periods. Amino acid formulations developed specifically for infants, namely Aminosyn PF and Trophamine, may protect against cholestasis associated with total parenteral nutrition (CATPN). The development of cholestasis may also be caused by other risk factors such as prematurity, surgery, sepsis, and extracorporeal membrane oxygenation (ECMO). To evaluate the relative effectiveness of the pediatric amino acid formulations in reducing CATPN, the courses of 70 infants < 1 year of age who received TPN for at least 14 days were reviewed. Cholestasis was defined as a conjugated serum bilirubin > or = 2 mg/dl subsequent to the initiation of TPN; CATPN was considered present when other factors related to cholestasis were ruled out. Liver function tests were recorded 24 h before starting TPN and at day 7, 15, and 21 during TPN infusion. Thirty infants (42.8%) developed cholestasis. CATPN was judged to have occurred in 15 (21.4%) of 70 infants, while 15 (21.4%) developed cholestasis secondary to other factors. Of the 15 CATPN patients, 7 had received Trophamine, 6 had received Aminosyn PF, and 2 had received both solutions. Aminosyn PF and Trophamine, along with other potential risk factors for CATPN such as antecedent surgery, sepsis, ECMO, prematurity, and nitrogen/calorie intake were analyzed by regression-analysis methods. None was statistically significant except the length of TPN (p = 0.0063). In conclusion, we cannot support the view that Trophamine is more effective than Aminosyn PF in the prevention of CATPN.

Parenteral drug administration guidelines for the pediatric patient: one hospital's recommendations

With the increasing use of intravenous drug therapy in the pediatric population, pharmacists are frequently faced with questions concerning appropriate methods of parenteral drug delivery. In some instances, these patients are also receiving parenteral nutrition solutions, and often have a limited fluid capacity caused by disease states such as congestive heart failure or renal insufficiency. Limited vascular access is also a frequent concern in the treatment of these patients. As a result, pharmacists are frequently asked whether a medication may be administered along with the PN solution. Although this practice is strongly discouraged, in many cases, especially in the pediatric patient, it is the only way to ensure that the patient is receiving adequate nutrition as well as appropriate drug therapy. Also, by administering medication with the PN solution, rather than interrupting the PN to administer medication, the patient is less likely to develop rebound hypoglycemia. The practice of administering medication through a central venous line intended for PN solutions is not without risks, however. Catheter sepsis and occlusion may result.