337 - Physiological Modulation of Suck–Respiration Coordination during Feeding in Healthy Term Neonates

Publication Number: 3324.337

Saya Yamada, Department of Pediatrics, The Jikei University Schoole of Medicine, Tokyo, Tokyo, Japan; Kensuke Kumazawa, Department of Pediatrics, The Jikei Univercity shool of Medicine, MInato-ku, Tokyo, Japan; Kimihiko Oishi, The Jikei University School of Medicine, MInato-ku, Tokyo, Japan; Chikako Mori, Research & Development Division, Pigeon Corporation, Tsukubamirai, Ibaraki, Japan; Kanae Yoshibe, Research＆Development Division,Pigeon Corporation, Tsukubamirai, Ibaraki, Japan

Background: Feeding in neonates requires precise coordination between sucking and respiration which develops naturally after birth. Previous studies have shown that sucking pressure differs between term and preterm infants, reflecting developmental maturity. However, feeding appears more complex: sucking strength and its coordination with respiration may vary over time even within a single session. Characterizing these dynamic interactions in healthy term neonates could provide fundamental insights into the acquisition of feeding skills in infants with feeding difficulties.

Objective: To examine temporal changes in sucking pressure and respiratory coordination during single feeding in term neonates using a novel system that simultaneously measures both parameters.

Design/Methods: Term infants born at our hospital between July and October 2025 were enrolled. Sucking pressure was measured using a custom-made device with a silicone-tipped artificial nipple connected to a semiconductor pressure transducer, while respiratory airflow was simultaneously recorded through a silicone tube attached to one side of a nasal prong. Measurements were performed once during bottle feeding within the first few days after birth. For each recording, maximum sucking pressure and the suck-respiration ratio (number of respirations per suck) were analyzed for the first and last 30 seconds of the session.

Results: Thirty-three term infants were included (median gestational age, 38.7 weeks [range: 37.1–40.3]; median birth weight, 2944 g [range: 2295–3406 g]; median age at measurement, 3 days [range: 1–4]). The overall median maximum sucking pressure was −143 mmHg (range: −191 to −80 mmHg). During the first 30 seconds of feeding, maximum sucking pressure was significantly higher than during the last 30 seconds (−180 mmHg [−244 to −126] vs. −140 mmHg [−180 to −59], p < 0.0001). Conversely, the suck-respiration ratio was significantly lower in the early phase compared with the later phase (0.78 [0.30–1.11] vs. 0.86 [0.20–1.21], p = 0.04).

Conclusion(s): Even in healthy term neonates, respiration tends to be suppressed while sucking pressure is stronger at the beginning of feeding, whereas respiration becomes more synchronized and sucking pressure decreases as feeding progresses. These findings indicate that dynamic modulation of sucking–respiration coordination occur even under normal physiological conditions and may help optimize feeding efficiency and maintain respiratory stability. Reduced respiratory involvement early in feeding may predispose infants with limited respiratory endurance, such as preterm neonates, to hypoxic episodes.