Objective: This study aimed to evaluate the association between electrical activity of the diaphragm (Edi) waveform patterns and peripheral oxygen saturation (SpO 2 ) in extremely preterm infants who are ventilated with neurally adjusted ventilatory assist (NAVA). Study Design:We conducted a retrospective cohort study at a level III neonatal intensive care unit. Extremely preterm infants born at our hospital between November 2019 and November 2020 and ventilated with NAVA were included. We collected Edi waveform data and classified them into four Edi waveform patterns, including the phasic pattern, central apnea pattern, irregular low-voltage pattern, and tonic burst pattern. We analyzed the Edi waveform pattern for the first 15 h of collectable data in each patient. To investigate the association between Edi waveform patterns and SpO 2 , we analyzed the dataset every 5 min as one data unit. We compared the proportion of each waveform pattern between the desaturation (Desat [+]) and non-desaturation (Desat [-]) groups.Results: We analyzed collected data for 105 h (1260 data units). The proportion of the phasic pattern in the Desat (+) group was significantly lower than that in the Desat (-) group (p < .001). However, the proportions of the central apnea, irregular low-voltage, and tonic burst patterns in the Desat (+) group were significantly higher than those in the Desat (-) group (all p < .05). Conclusion:Our results indicate that proportions of Edi waveform patterns have an effect on desaturation of SpO 2 in extremely preterm infants who are ventilated with NAVA.

Background Metabolic bone disease (MBD) is a common disorder in extremely low‐birth‐weight (ELBW) infants. However, no studies have investigated whether high‐dose calcium (Ca) and phosphorus (P) supplementation by parenteral nutrition (PN) prevents MBD in ELBW infants. This study aimed to identify the effect of PN on MBD in ELBW infants. Methods We retrospectively analyzed ELBW infants who were admitted between April 2011 and March 2017. ELBW infants were divided into the low‐P group (n = 22) and the high‐P group (n = 26) according to the dose of parenteral P supply. Biochemical and radiological markers of MBD and treatments were analyzed. Results Mean daily parenteral intake of Ca and P in the first week was significantly higher in the high‐P group than in the low‐P group (both P ≤ .001). Serum alkaline phosphatase (ALP) levels were significantly higher in the low‐P group than in the high‐P group in the first month. ELBW infants in the low‐P group received alfacalcidol much more frequently than those in the high‐P group. There was a trend of a higher rate of x‐ray changes in the low‐P group than in the high‐P group. No infants developed bone fractures. Conclusion Appropriate P intake by PN is required to ensure high Ca intake, reduce ALP levels in the first month, and prevent MBD from hyperparathyroidism and does not worsen x‐ray findings in ELBW infants.

Aims/Introduction: It was reported that fetuses secrete endogenous incretin; however, the stimulants of fetal incretin secretion are not fully understood. To investigate the association between the passage of amniotic fluid through the intestinal tract and fetal secretion of incretin, we analyzed umbilical cord incretin levels of infants with duodenum atresia. Materials and Methods: Infants born from July 2017 to July 2019 (infants with duodenum atresia and normal term or preterm infants) were enrolled. We measured and compared the concentrations of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide/glucose-dependent insulinotropic polypeptide (GIP) in the umbilical vein and preprandial blood samples after birth. Results: A total of 98 infants (47 term, 46 preterm and 5 with duodenum atresia) were included. In patients with duodenum atresia, umbilical vein GLP-1 and GIP levels were the same as those in normal infants. In postnatal samples, there were positive correlations between the amount of enteral feeding and preprandial serum concentrations of GLP-1 (r = 0.47) or GIP (r = 0.49). Conclusions: Our results show that enteral feeding is important for secretion of GLP-1 and GIP in postnatal infants, whereas the passage of amniotic fluid is not important for fetal secretion of GLP-1 and GIP. The effect of ingested material passing through the digestive tract on incretin secretion might change before and after birth. Other factors might stimulate secretion of GLP-1 and GIP during the fetal period.

Objective This study aimed to evaluate the change in the waveform pattern of the electrical activity of the diaphragm (Edi) following the administration of doxapram in extremely preterm infants ventilated with neurally adjusted ventilatory assist (NAVA). Study Design We conducted this retrospective cohort study in our neonatal intensive care unit between November 2019 and September 2021. The study participants were extremely preterm infants under the gestational age of 28 weeks who were ventilated with NAVA and administered doxapram. We collected the data of the Edi waveform pattern and calculated the proportion. To analyze the change in the proportion of the Edi waveform pattern, we compared the proportion of the data for 1 h before and after doxapram administration. Results Ten extremely preterm infants were included. Almost all the patients’ respiratory condition improved after doxapram administration. The ventilatory parameters—Edi peak, Edi minimum, peak inspiratory pressure, time in backup ventilation, and number of switches to backup ventilation—did not change significantly. However, the proportion of phasic pattern significantly increased (before: 46% vs. after: 72%; p < 0.05), whereas the central apnea pattern significantly decreased after doxapram administration (before: 31% vs. after: 8.3%; p < 0.05). The proportion of irregular low‐voltage patterns tended to decrease, albeit with no significant changes. Conclusion Our results indicated that the proportion of Edi waveform patterns changed following doxapram administration. Edi waveform pattern analysis could be a sensitive indicator of effect with other intervention for respiratory conditions.