Mathew O P
Department of Pediatrics, University of Texas Medical Branch, Galveston 77550.
Am J Dis Child. 1990 Feb;144(2):222-4. doi: 10.1001/archpedi.1990.02150260102039.
The aim of the present study was to elucidate the role of hole size and thickness in determining milk flow through nipple units during bottle feeding. Commonly used standard nipple units (SMA single-hole, Enfamil single-hole, and Twist-on) for term and preterm infants, as well as Nuk-type nipple units (SMA Nuk, Enfamil Natural, and Nuk) were tested. The size of the nipple hole and wall thickness were determined for each nipple unit. Airflow was measured by forcing pressurized air through the feed hole. Simulated sucks were used to measure the milk flow. A marked variability in airflow and milk flow was observed within and among the various types of nipple units studied. Within each type of nipple unit, both milk flow and airflow measurements correlated well with hole size. The thickness of the nipple units contributed minimally to the observed variability. We conclude that differences in hole size primarily account for the observed variability in milk flow. This finding may be clinically important in that rapid milk flow can lead to apnea and bradycardia in some preterm infants. The above observations imply that design changes are necessary to reduce the variability of milk flow within each nipple type. Moreover, milk-flow measurements made using a simple mechanical system and airflow measurements used by the industry are equally sensitive to evaluate nipple flow.
本研究的目的是阐明孔径和厚度在奶瓶喂养期间决定乳汁通过奶嘴部件流动方面所起的作用。对足月儿和早产儿常用的标准奶嘴部件（SMA单孔、美赞臣单孔和旋拧式）以及努克型奶嘴部件（SMA努克、美赞臣自然款和努克）进行了测试。测定了每个奶嘴部件的奶嘴孔大小和壁厚。通过迫使压缩空气通过进料孔来测量气流。使用模拟吸吮来测量乳汁流量。在所研究的各类奶嘴部件内部和之间均观察到气流和乳汁流量存在显著差异。在每种奶嘴部件类型中，乳汁流量和气流测量值均与孔径密切相关。奶嘴部件的厚度对所观察到的差异影响极小。我们得出结论，孔径差异主要导致了所观察到的乳汁流量差异。这一发现可能具有临床重要性，因为乳汁快速流动可能导致一些早产儿出现呼吸暂停和心动过缓。上述观察结果表明，有必要进行设计改进以减少每种奶嘴类型内乳汁流量的差异。此外，使用简单机械系统进行的乳汁流量测量和行业所采用的气流测量在评估奶嘴流量方面同样灵敏。
