Pasteurized Donor Human Milk Maintains Microbiological Purity for 4 Days at 4°C.

BACKGROUND: Most protective components in human milk are stable during prolonged storage at 4ºC; however, pasteurization reduces some microbicidal activities responsible for suppressing microbial growth and protecting against infection. Donor milk used by neonatal intensive care units (NICUs) is frozen pasteurized donor human milk (PDHM) defrosted and stored at 4ºC. Current Human Milk Banking Association of North America (HMBANA) Best Practice guidelines recommend that milk be discarded 24 hours after being thawed, but experimental data on the duration of microbiological purity in thawed PDHM are sparse. OBJECTIVE: This study evaluates microbiological purity of thawed PDHM during prolonged storage at 4ºC. METHODS: A total of 42 independent, randomly selected PDHM samples were thawed at 4ºC. As is typical in NICUs, each bottle was opened at 3-hour intervals and 3 mL was withdrawn with a sterile syringe and transferred into a sterile tube. The 3 mL samples removed at 0, 24, 48, 72, 96 hours, and 9 days were tested for the presence of any microorganisms by a clinical laboratory that routinely screens PDHM for microbes. RESULTS: No evidence of microbial growth was observed in cultured samples taken at 0 to 9 days after thawing of the milk samples. CONCLUSION: There was no evidence of microbes in PDHM as dispensed by HMBANA milk banks when defrosted and stored at 4ºC for up to 9 days. Extended storage of PDHM in the NICU could reduce waste of donor milk, thereby increasing availability of human milk to vulnerable neonatal patients.

Comparison of lipid and calorie loss from donor human milk among 3 methods of simulated gavage feeding: one-hour, 2-hour, and intermittent gravity feedings.

PURPOSE: The objective of this study was to compare the differences in lipid loss from 24 samples of banked donor human milk (DHM) among 3 feeding methods: DHM given by syringe pump over 1 hour, 2 hours, and by bolus/gravity gavage. DESIGN: Comparative, descriptive. There were no human subjects. METHODS: Twenty-four samples of 8 oz of DHM were divided into four 60-mL aliquots. Timed feedings were given by Medfusion 2001 syringe pumps with syringes connected to narrow-lumened extension sets designed for enteral feedings and connected to standard silastic enteral feeding tubes. Gravity feedings were given using the identical syringes connected to the same silastic feeding tubes. All aliquots were analyzed with the York Dairy Analyzer. Univariate repeated-measures analyses of variance were used for the omnibus testing for overall differences between the feeding methods. Lipid content expressed as grams per deciliter at the end of each feeding method was compared with the prefed control samples using the Dunnett's test. The Tukey correction was used for other pairwise multiple comparisons. RESULTS: The univariate repeated-measures analysis of variance conducted to test for overall differences between feeding methods showed a significant difference between the methods (F = 58.57, df = 3, 69, P < .0001). Post hoc analysis using the Dunnett's approach revealed that there was a significant difference in fat content between the control sample and the 1-hour and 2-hours feeding methods (P < .0001), but we did not find any significant difference in fat content between the control and the gravity feeding methods (P = .3296). Pairwise comparison using the Tukey correction revealed a significant difference between both gravity and 1-hour feeding methods (P < .0001), and gravity and 2-hour feeding method (P < .0001). There was no significant difference in lipid content between the 1-hour and 2-hour feeding methods (P = .2729). CONCLUSIONS: Unlike gravity feedings, the timed feedings resulted in a statistically significant loss of fat as compared with their controls. These findings should raise questions about how those infants in the neonatal intensive care unit are routinely gavage fed.