Accuracy of a User-Friendly Centrifuge for Measuring Creamatocrits on Mothers' Milk in the Clinical Setting

Abstract

The creamatocrit (CRCT), a simple, accurate, and inexpensive technique for the estimation of lipid and caloric content in mothers' milk, has been used extensively in lactation research, but has not been integrated into the routine management of clinical lactation problems such as slow weight gain in mothers' milk-fed preterm and term infants. The Creamatocrit Plus is a lightweight, noiseless centrifuge with an embedded reader that automatically calculates lipid and calories from the CRCT value, making it ideal for use in the clinical setting. This study compared intra-user and inter-user reliability, the equivalence of the CRCT values obtained with the Creamatocrit Plus to the two standard techniques for performing CRCTs: the standard laboratory centrifuge with a hematocrit reader and the standard laboratory centrifuge with digital calipers, and the predictive accuracy of the Creamatocrit Plus for estimating the lipid and caloric content in mothers' milk. CRCTs were performed using the three techniques on 36 milk specimens from 12 women. Laboratory analyses of lipid and calories were performed by investigators blinded to CRCT values. The mean absolute intra-user and inter-user differences were all <1% CRCT, and the mean CRCT measures were nearly identical for the three measurement techniques. Linear correlations between CRCT and laboratory measures for lipid (r = 0.95) and calories (r = 0.94) were very high. The authors conclude that the Creamatocrit Plus can replace cumbersome laboratory equipment for measuring CRCTs in the clinical setting.

The effect of maternal habitus on macronutrient content of human milk colostrum

“…Although a useful bedside, cheap estimate of human milk fat and caloric content, creamatocrit is less accurate and even tends to overestimate human milk fat as compared with biochemical methods or midinfrared technology. 18,19 Finally, the method of milk expression is not described in the study by Fujimori et al, 10 and it is unclear to us how these authors were technically able to obtain 10 ml of colostrum in all participants; indeed as colostrum production consists of only a few milliliters during the first few days of life, 20 we speculate that the 10 ml collection was a cumulative collection over the few days in the study by Fujimori et al 10 In our study, maternal BMI appeared not to significantly correlate with most macronutrient and energy content of human colostrums, with the exception of protein concentration. The positive correlation between protein concentration in colostrum and maternal BMI requires a few comments: first, its mechanism is unclear, and among other possibilities, it would be important to determine whether differences in maternal diet might be influential.…”

Human milk macronutrient analysis using point-of-care near-infrared spectrophotometry

“…Meier et al 20 used a creamatocrit device and showed it is an accurate way to measure fat (r 2 ¼ 0.90). Creamatocrit, however, does not measure carbohydrate or protein.…”

“…Currently available methods for measuring human milk content include the creamatocrit, ultrasonic analyzers, midinfrared spectrophotometers and near-infrared (NIR) spectrophotometry. [19][20][21] NIR spectrophotometry is a promising method for providing point-of-care measurements of human milk macronutrients with several distinct advantages over other technologies. NIR spectrophotometry uses the wavelength spectrum 1200 to 2400 nm to analyze material of solid and liquid states.…”

Simultaneous Breast Expression in Breastfeeding Women Is More Efficacious Than Sequential Breast Expression

“…Moreover, the improved efficacy of SIM expression resulted in milk that had a higher cream content compared with SEQ expression (Table 2). Given the close relationship between the cream content and the energy content of milk, 14 the milk yielded by SIM will have a higher energy content than that yielded by SEQ.…”

“…12 During this period, mothers hand-expressed small milk samples (< 1 mL) into 5-mL polypropylene vials (Disposable Products, Adelaide, Australia), immediately before and after each breastfeed or expression. The breastfeed volumes and cream contents of the milk samples (measured by the creamatocrit method 13 on the Creamatocrit PlusÔ device 14 [Medela Inc., McHenry, IL]) were used to calculate the breastfeeding storage capacity as described previously. 15 Before and after each pumping session the mothers hand-expressed small milk samples (< 1 mL) from the breast being expressed.…”