Severe Bronchopulmonary Dysplasia Adversely Affects Brain Growth in Preterm Infants.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) is associated with neurodevelopmental outcomes of preterm infants, but its effect on brain growth in preterm infants after the neonatal period is unknown. This study aimed to evaluate the effect of severe BPD on brain growth of preterm infants from term to 18 months of corrected age (CA). METHODS: Sixty-three preterm infants (42 with severe BPD and 21 without severe BPD) who underwent magnetic resonance imaging at term equivalent age (TEA) and 18 months of CA were studied by using the Infant Brain Extraction and Analysis Toolbox (iBEAT). We measured segmented brain volumes and compared brain volume and brain growth velocity between the severe BPD group and the non-severe BPD group. RESULTS: There was no significant difference in brain volumes at TEA between the groups. However, the brain volumes of the total brain and cerebral white matter in the severe BPD group were significantly smaller than those in the non-severe BPD group at 18 months of CA. The brain growth velocities from TEA to 18 months of CA in the total brain, cerebral cortex, and cerebral white matter in the severe BPD group were lower than those in the non-severe BPD group. CONCLUSION: Brain growth in preterm infants with severe BPD from TEA age to 18 months of CA is less than that in preterm infants without severe BPD.

Potential treatment option of rivaroxaban for breastfeeding women: A case series.

The use of direct oral anticoagulants (DOACs) in breastfeeding women is currently challenging due to limited safety data for breastfeeding infants, and there have been no previous studies on the drug concentration in breastfeeding infants. We treated 2 patients (one case was twin pregnancy) with venous thromboembolisms in breastfeeding women administered rivaroxaban at our institution. Blood samples from the mothers and breastmilk samples were collected at time 0 and 2 h after the rivaroxaban administration, breastfeeding was conducted 2 h after the rivaroxaban administration, and blood samples from the infants were collected 2 h after breastfeeding (4 h after maternal rivaroxaban administration). The milk-to-plasma (M:P) ratios were 0.27 in Case 1 and 0.32 in Case 2. The estimated relative infant dose (RID) was 0.82 % in Case 1 Children 1 and 2, and 1.27 % in Case 2. The rivaroxaban concentration in the infant plasma was below the lower limit of quantification in all infants. In addition, even in the high-exposure case simulation based on 5 days of breastfeeding in Case 2, the infant plasma concentration level was below the lower limit of quantification. At 3 months of follow-up, breastfeeding was continued, and all infants grew and developed without any health problems including bleeding events. The current case series showed that there were no pharmacokinetic or clinical concerns for breastfeeding women or breastfed infants, and provides support for rivaroxaban as a safe treatment option for these patients.

Comparison of two methods measuring serum alkaline phosphatase in neonates.

BACKGROUND: Serum alkaline phosphatase (ALP) is a useful bone turnover marker to diagnose metabolic bone disease in preterm infants. In Japan, serum ALP levels were generally measured using the Japan Society of Clinical Chemistry (JSCC) method. It is problematic that ALP levels measured using the JSCC method tend to be higher in people with blood types B and O regardless of the disease. For international standardization, since 2020, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) method has been used as a reference method for ALP measurement instead of the JSCC method. However, no report has investigated the correlation between these two methods in neonates. We therefore aimed to compare the JSCC and IFCC methods and demonstrate a conversion formula in neonates. METHODS: In this retrospective study, we used a total of 402 samples in 49 preterm and 38 term infants. Serum ALP levels were measured using the JSCC and IFCC methods. RESULTS: Alkaline phosphatase measured using the JSCC method strongly correlated with that measured using the IFCC method in all blood types in preterm and term infants (P < 0.01 for all). CONCLUSIONS: We found that the serum ALP levels measured using the IFCC method could be calculated as 0.34 times the ALP levels measured using the JSCC method in preterm and term infants with any blood type: ALP levels (IFCC method) = 0.34 × ALP levels (JSCC method).

Effect of doxapram on the electrical activity of the diaphragm waveform pattern of preterm infants.

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.

Effect of electrical activity of the diaphragm waveform patterns on SpO2 for extremely preterm infants ventilated with neurally adjusted ventilatory assist.

OBJECTIVE: This study aimed to evaluate the association between electrical activity of the diaphragm (Edi) waveform patterns and peripheral oxygen saturation (SpO2 ) 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 SpO2 , 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 SpO2 in extremely preterm infants who are ventilated with NAVA.

Antenatal Glucocorticoids Reduce the Incidence of Refractory Hypotension in Low Birthweight Infants during the Early Neonatal Period, but Do Not Affect It beyond This Time.

OBJECTIVE: This study aimed to clarify the effect of antenatal glucocorticoids (AGs) on the incidence of refractory hypotension (RH) in very low birthweight (VLBW) infants after the first week of life. STUDY DESIGN: We included VLBW infants born at a gestational age of <30 weeks and divided them into three groups: the complete group (born within 7 days of completing a single course [two doses] of AGs), the incomplete group (born without complete course), and the late delivery group (born at ≥8 days after a single course). We compared the incidence and period of onset of RH among the three groups. RESULTS: A total of 115 infants were enrolled. The incidence of RH in the first week of life was significantly lower in the complete group than in the other groups. However, there was no significant difference in the incidence of RH after the first week of life among the groups. CONCLUSION: AGs contribute to circulatory stabilization during the first week of life, but this effect does not last after 1 or 2 weeks of administration. In infants who receive AGs, physicians should consider that the risk of RH after the first week of life is not low.

Clinical features of very-low-birthweight infants with congenital heart disease.

BACKGROUND: Few studies have investigated the developmental prognosis of very-low-birthweight (VLBW) infants with congenital heart diseases (CHDs). This study aimed to determine the mortality and morbidity, including the developmental prognosis, of VLBW infants with CHD. METHODS: This single-center, retrospective cohort study included VLBW infants admitted to the neonatal intensive care unit from January 2006 to December 2011. Perinatal records were reviewed for CHD diagnosis, treatment details, comorbidities, mortality, and long-term neurodevelopmental outcomes. The characteristics and neurological developmental quotients at around the age of 3 years were compared among the following three groups of VLBW infants with CHDs: biventricular circulation without intervention (without surgery), biventricular circulation with intervention (catheter intervention or one-stage surgery), and single-ventricular circulation (Fontan-type multiple-stage surgery). RESULTS: Among a total of 449 VLBW infants admitted during this period, 45 (10.0%) infants had CHDs, including 25 infants with congenital abnormalities (chromosomal abnormalities and/or multiple anomalies). All 13 infants who died before discharge had congenital abnormalities. The incidence rates of comorbidities were not higher in VLBW infants with CHDs than in those without CHDs. The developmental quotients of the no-surgery, catheter intervention or one-stage surgery, and Fontan-type multiple-stage surgery groups were 87.2 ± 10.9, 91.3 ± 4.7, and 63.7 ± 8.6, respectively. CONCLUSIONS: The neurological development at around the age of 3 years in VLBW infants with biventricular circulation was in the borderline-to-normal range; however, that in infants with single-ventricular circulation was poor. Further studies are needed to comprehend the neurological development of VLBW infants with CHDs better.

Effects of passage through the digestive tract on incretin secretion: Before and after birth.

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.

Appropriate Phosphorus Intake by Parenteral Nutrition Prevents Metabolic Bone Disease of Prematurity in Extremely Low-Birth-Weight Infants.

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.