Administering Parenteral Nutrition in the Neonatal Intensive Care Unit: Logistics, Existing Challenges, and a Few Conundrums

Use of parenteral nutrition (PN) in the neonatal intensive care unit (NICU) requires evaluating the need for central venous catheters, potential drug incompatibilities, unintentional exposures, and suboptimal energy and nutrient intake during the transition to full enteral nutrition. Risks of photooxidation reactions in PN components, refeeding syndrome, and excess early amino acid intake should prompt the reevaluation of routine practices. The goal of this paper is to review the practicalities, challenges, and conundrums of administering PN in the NICU.

Small Proportion of Low-Birth-Weight Infants With Ostomy and Intestinal Failure Due to Short-Bowel Syndrome Achieve Enteral Autonomy Prior to Reanastomosis

BACKGROUND

It is challenging to provide optimum nutrition in low-birth-weight (LBW) infants with short-bowel syndrome (SBS) and ostomy. This study aims to evaluate the clinical course of LBW infants with SBS and ostomy in response to enteral feeds, recognize characteristics associated with achievement of enteral autonomy prior to reanastomosis, and evaluate associated short-term outcomes.

METHODS

A retrospective analysis of 52 LBW neonates with intestinal failure (IF) caused by SBS and ostomy treated in a neonatal intensive care unit from 2012 to 2018 was performed. Clinical characteristics and short-term outcomes were studied in relation to the location of the ostomy and the success with enteral feeding achieved prior to reanastomosis.

RESULTS

Of the 52 infants with SBS, jejunostomy, ileostomy, and colostomy were present in 9, 40, and 3 infants, respectively. Fourteen (26.92%) infants achieved enteral autonomy transiently, and 7 (13.46%) sustained until reanastomosis. All 9 infants with jejunostomy were parenteral nutrition dependent, compared with 22 with ileostomy and none with colostomy (P = 0.002). Infants who achieved enteral autonomy showed lower incidence of cholestasis (P = 0.038) and better growth velocity (P = 0.02) prior to reanastomosis.

CONCLUSIONS

A minority of LBW infants with SBS and ostomy achieved enteral autonomy prior to reanastomosis. Distal ostomy (ileostomy and colostomy), reduced cholestasis, and better growth were associated with achievement of enteral autonomy. Our report highlights the challenges in establishing enteral autonomy in LBW infants with IF and ostomy, and the feasibility of that approach in a minority of patients, with tangible benefits.

Peripherally inserted central catheters optimize nutrient intake in moderately preterm infants

BACKGROUND

While very preterm (<32 wk gestation) infants are routinely provided intensive nutritional support via central line, clinical practice varies for nutrient delivery in infants born moderately preterm (32-34 wk gestation). We sought to define the impact of nutritional support via peripherally inserted central catheter (PICC) on nutrient delivery in the first 2 wk of life and growth by discharge.

METHODS

Data were extracted from the records of 187 infants born between 32 and 34 6/7 wk gestation and admitted to the University of Iowa Children's Hospital between April 2012 and December 2013. Records of all feedings, weights, and PICC placements were collected. The growth outcomes at discharge for infants who received nutrition via PICC were compared to those who did not.

RESULTS

In the first week of life, newborns who received nutrition via PICC line received 17.6 more kilocalories (confidence interval (CI): 12.5-22.7, P < 0.001) and 1.2 more grams protein per kilogram body weight per day (CI: 0.9-1.4, P < 0.001) compared to control infants. By discharge, the PICC group had gained 302 g more body weight (P < 0.001).

CONCLUSION

This study demonstrates superior nutrient intake and growth in the first 2 wk of life for infants who received nutrition via PICC line.

Dietary resistant starch prevents urinary excretion of 25-hydroxycholecalciferol and vitamin D-binding protein in type 1 diabetic rats

Diabetes is a rapidly growing epidemic affecting millions of Americans and has been implicated in a number of devastating secondary complications. We previously demonstrated that type 2 diabetic rats exhibit vitamin D deficiency due to aberrant megalin-mediated endocytosis and excessive urinary excretion of 25-hydroxycholecalciferol (25D3) and vitamin D-binding protein (DBP). Here, we examined whether a model of type 1 diabetes [T1D; streptozotocin (STZ)-treated Sprague-Dawley rats] would similarly excrete abnormally high concentrations of 25D3 and DBP due to renal damage and compromised expression of megalin and its endocytic partner, disabled-2 (Dab2). Moreover, we tested whether feeding diabetic rats starch that is resistant to digestion could alleviate these abnormalities. Control (n = 12) rats were fed a standard, semipurified diet (AIN-93G) containing 55% total dietary starch and STZ-treated rats were fed the AIN-93G diet (n = 12) or a diet containing 55% high-amylose maize that is partially resistant to digestion [20% total dietary resistant starch (RS); n = 12] for 2 and 5 wk. The RS diet attenuated weight loss and polyuria in STZ-treated rats. Histology and immunohistochemistry revealed that dietary RS also attenuated the loss of Dab2 expression in renal proximal tubules. Moreover, urinary concentrations of both 25D3 and DBP were elevated ∼10-fold in STZ-treated rats (5 wk post STZ injection), which was virtually prevented by the RS. We also observed a ∼1.5-fold increase in megalin mRNA expression in STZ-treated rats, which was attenuated by feeding rats the RS diet for 2 wk. Taken together, these studies indicate that consumption of low-glycemic carbohydrates can attenuate disruption of vitamin D homeostasis in T1D through the rescue of megalin-mediated endocytosis in the kidney.

Homocysteine imbalance: a pathological metabolic marker

Perturbations in methyl group metabolism and homocysteine balance have emerged over the past few decades as having defining roles in a number of pathological conditions. Numerous nutritional, hormonal, and genetic factors that are characterized by elevations in circulating homocysteine concentrations are also associated with specific pathological conditions, including cancer development, autoimmune diseases, vascular dysfunction, and neurodegenerative disease. Although much remains to be explored, our understanding of the relationship between disease, methyl balance, and epigenetic control of gene expression has steadily progressed. However, homocysteine balance and its role in health and disease are not as clearly understood. This review presents our current understanding of homocysteine metabolism and its link to specific pathologies.