Energy and Protein Intake During the Transition from Parenteral to Enteral Nutrition in Infants of Very Low Birth Weight.

OBJECTIVE: To evaluate the association between nutrition delivery practices and energy and protein intake during the transition from parenteral to enteral nutrition in infants of very low birth weight (VLBW). STUDY DESIGN: This was a retrospective analysis of 115 infants who were VLBW from a regional neonatal intensive care unit. Changes in energy and protein intake were estimated during transition phase 1 (0% enteral); phase 2 (>0, ≤33.3% enteral); phase 3 (>33.3, ≤66.7% enteral); phase 4 (>66.7, <100% enteral); and phase 5 (100% enteral). Associations between energy and protein intake were determined for each phase for parenteral nutrition, intravenous lipids, central line, feeding fortification, fluid restriction, and excess non-nutritive fluid intake. RESULTS: In phases 2 and 3, infants receiving feeding fortification received less protein than infants who were unfortified (-1.1 and -0.3 g/kg/d, respectively; P < .001). However, this negative association was not observed after adjusting for relevant nutrition delivery practices. Despite greater enteral protein intake during phases 2 and 3 (0.3 and 0.8 g/kg/d, respectively; P < .001), infants with early fortification received less parenteral protein than infants who were unfortified (-1.4 and -1.1 g/kg/d, respectively; P < .001). Similar patterns were observed for energy intake. Protein intake declined during phases 3 and 4. CONCLUSIONS: Infants paradoxically received less protein and energy on days with early fortification, suggesting that clinicians may lack easily accessible data to detect the association between nutrition delivery practices and overall nutrition in infants who are VLBW.

Association Between the 7-Day Moving Average for Nutrition and Growth in Very Low Birth Weight Infants.

BACKGROUND: Very low birth weight (VLBW) infants remain at risk for postnatal growth restriction. Clinicians may have difficulty identifying growth patterns resulting from nutrition interventions, impeding prompt management changes intended to increase growth velocity. This study aimed to quantify the association between growth and nutrition intake through 7-day moving averages (SDMAs). METHODS: The first 6 weeks of daily nutrition intake and growth measurements were collected from VLBW infants admitted to a level 4 neonatal intensive care unit (2011-2014). The association between SDMA for energy and macronutrients and subsequent 7-day growth velocities for weight, length, and head circumference were determined using mixed effects linear regression. Analyses were adjusted for fluid intake, infant characteristics, and comorbid conditions. RESULTS: Detailed enteral and parenteral caloric provisions were ascertained for 115 infants (n = 4643 patient-days). Each 10-kcal/kg/d increase over 7 days was independently associated with increased weight (1.7 g/kg/d), length (0.4 mm/wk), and head circumference (0.9 mm/wk; P < .001, for weight and head circumference; P = .041 for length). Each 1 g/kg/d macronutrient increase was also associated with increased weight (protein, P = .027; fat and carbohydrates, P < .001), increased length (fat, P = .032), and increased head circumference (fat and carbohydrates, P < .001). CONCLUSIONS: The SDMA identifies clinically meaningful associations among total energy, macronutrient dosing, and growth in VLBW infants. Whether SDMA is a clinically useful tool for providing clinicians with prompt feedback to improve growth warrants further attention.

Progesterone treatment shows greater protection in brain vs. retina in a rat model of middle cerebral artery occlusion: Progesterone receptor levels may play an important role.

BACKGROUND/OBJECTIVE: To determine whether inflammation increases in retina as it does in brain following middle cerebral artery occlusion (MCAO), and whether the neurosteroid progesterone, shown to have protective effects in both retina and brain after MCAO, reduces inflammation in retina as well as brain. METHODS: MCAO rats treated systemically with progesterone or vehicle were compared with shams. Protein levels of cytosolic NF-κB, nuclear NF-κB, phosphorylated NF-κB, IL-6, TNF-α, CD11b, progesterone receptor A and B, and pregnane X receptor were assessed in retinas and brains at 24 and 48 h using western blots. RESULTS: Following MCAO, significant increases were observed in the following inflammatory markers: pNF-κB and CD11b at 24 h in both brain and retina, nuclear NF-κB at 24 h in brain and 48 h in retina, and TNF-α at 24 h in brain.Progesterone treatment in MCAO animals significantly attenuated levels of the following markers in brain: pNF-κB, nuclear NF-κB, IL-6, TNF-α, and CD11b, with significantly increased levels of cytosolic NF-κB. Retinas from progesterone-treated animals showed significantly reduced levels of nuclear NF-κB and IL-6 and increased levels of cytosolic NF-κB, with a trend for reduction in other markers. Post-MCAO, progesterone receptors A and B were upregulated in brain and downregulated in retina. CONCLUSION: Inflammatory markers increased in both brain and retina after MCAO, with greater increases observed in brain. Progesterone treatment reduced inflammation, with more dramatic reductions observed in brain than retina. This differential effect may be due to differences in the response of progesterone receptors in brain and retina after injury.

Progesterone treatment in two rat models of ocular ischemia.

PURPOSE: To determine whether the neurosteroid progesterone, shown to have protective effects in animal models of traumatic brain injury, stroke, and spinal cord injury, is also protective in ocular ischemia animal models. METHODS: Progesterone treatment was tested in two ocular ischemia models in rats: a rodent anterior ischemic optic neuropathy (rAION) model, which induces permanent monocular optic nerve stroke, and the middle cerebral artery occlusion (MCAO) model, which causes transient ischemia in both the retina and brain due to an intraluminal filament that blocks the ophthalmic and middle cerebral arteries. Visual function and retinal histology were assessed to determine whether progesterone attenuated retinal injury in these models. Additionally, behavioral testing and 2% 2,3,5-triphenyltetrazolium chloride (TTC) staining in brains were used to compare progesterone's neuroprotective effects in both retina and brain using the MCAO model. RESULTS: Progesterone treatment showed no effect on visual evoked potential (VEP) reduction and retinal ganglion cell loss in the permanent rAION model. In the transient MCAO model, progesterone treatment reduced (1) electroretinogram (ERG) deficits, (2) MCAO-induced upregulation of glutamine synthetase (GS) and glial fibrillary acidic protein (GFAP), and (3) retinal ganglion cell loss. As expected, progesterone treatment also had significant protective effects in behavioral tests and a reduction in infarct size in the brain. CONCLUSIONS: Progesterone treatment showed protective effects in the retina following MCAO but not rAION injury, which may result from mechanistic differences with injury type and the therapeutic action of progesterone.