Different expressions of cardiac biomarkers between different types of acquired right ventricular outflow tract abnormality in monochorionic twins.

OBJECTIVE: To investigate the differences in amniotic fluid cardiac biomarkers and clinical features among types of right ventricular outflow tract (RVOT) abnormality in monochorionic (MC) twins. METHOD: This prospective study included MC twins that underwent laser surgery. Recipient or larger twins (group A) and donor or smaller twins (group B) were assessed and divided into those with a normal right ventricular outflow tract (normal RVOT), functional pulmonary atresia (fPA), or pulmonary stenosis (PS). Amniotic fluid levels of NT-proBNP (afNT-proBNP) and cardiac troponin T (afTnT) were examined during surgery. RESULTS: Of 190 fetuses in group A, there were 14 RVOT abnormality cases (including 7 fPA and 7 PS). No group B fetuses showed RVOT abnormality findings. In group A, later and earlier gestational age at surgery were observed in fPA (25.1 ± 2.8 weeks) and PS groups (17.8 ± 0.9 weeks). All survived PS cases demonstrated progressive pulmonary valve obstruction, not observed in fPA groups. AfNT-proBNP were significantly higher in fPA and PS than in the normal RVOT group (p < 0.05). AfTnT was significantly higher in group A with PS than fPA and normal RVOT groups (p < 0.05). CONCLUSION: Among RVOT abnormality types in group A, amniotic fluid cardiac biomarkers were differently expressed, and clinical features were also differentiated. These findings provide insight into the pathophysiological influence on RVOT in MC twins. CLINICAL TRIAL REGISTRATION: This study was registered with the Japanese Clinical Trial Registry "UMIN-CTR" (http://www.umin.ac.jp/ctr/index-j.htm; trial ID numbers UMIN000024486 and 000037702).

Intravitreal bevacizumab treatment reduces ocular blood flow in retinopathy of prematurity: a four-case report.

PURPOSE: To evaluate the relationship between ocular blood flow, expressed as mean blur rate (MBR) by laser speckle flowgraphy, and intravitreal bevacizumab (IVB) therapy in neonates with retinopathy of prematurity (ROP). METHODS: This was a case series study of 4 neonates with ROP under sedation before and after IVB and evaluated 8 eyes, in which the circulation could be measured three times consecutively. We performed optic nerve head blood flow measurement and fluorescein angiography (FA) before and 1 week after treatment. Blood flow was analyzed separately for MBR-A (mean of all values), MBR-V (vessel mean), and MBR-T (tissue mean). Comparisons between the MBR (-A, -V, -T), body weight, and other systemic and ocular parameters before and after treatment were performed using a paired t test. RESULTS: The MBR values after IVB were lower than the pre-treatment values in all cases. All eyes showed leakage at neovascularization on FA before treatment. Although leakage improved 1 week after treatment, the neovascularization did not completely regress. CONCLUSIONS: IVB improves vein dilation and artery tortuosity, while reducing ocular blood flow in neonates with ROP. We suggest that neovascularization might not be involved in reducing ocular blood flow in the early stage of IVB treatment.

Decreased ocular blood flow after photocoagulation therapy in neonatal retinopathy of prematurity.

PURPOSE: To evaluate the relationships between optic nerve head blood flow, expressed as mean blur rate (MBR) measured by laser speckle flowgraphy (LSFG), and photocoagulation therapy in neonates with retinopathy of prematurity (ROP). STUDY DESIGN: Case series study. METHODS: We studied 5 ROP neonates either during sleep or under sedation both before and after photocoagulation, and evaluated 8 eyes in which the circulation could be measured three times consecutively. Correlations between the MBR-A (mean of all values), MBR-V (vessel mean) and MBR-T (tissue mean) and postmenstrual age were evaluated using Spearman's rank correlation coefficient. In addition, correlations between the relative MBR (-A, -V, -T) value and number of photocoagulation burns and the NV score were evaluated. Differences between post-treatment MBR in ROP subjects and normal neonates' MBR were estimated using analysis of covariance (ANCoVA), with adjustment for postmenstrual age. RESULTS: The relative MBR (-A, -V, -T) values after photocoagulation were 69.6 ± 16.0%, 66.7 ± 17.0% and 74.3 ± 14.6%, respectively. Postmenstrual age was significantly correlated with post-treatment MBR-A (r = 0.83, p = 0.0101), MBR-V (r = 0.85, p = 0.007) and MBR-T (r = 0.76, p = 0.0282). The relative MBR-T value was significantly correlated with the number of photocoagulation burns (r = -0.75, p = 0.033) and NV score (r = -0.72, p = 0.0437). The ANCoVA results showed no significant difference between post-treatment MBR and normal neonates' MBR. CONCLUSIONS: Photocoagulation improved the dilation of veins and tortuosity of arteries and reduced ocular blood flow in ROP subjects. Since the post-treatment MBR was not different from a normal neonate's MBR, it is suggested that the pre-treatment MBR was higher in severe ROP cases.

Target value of oxygen saturation during the first 10 min after birth.

BACKGROUND: During neonatal resuscitation, careful oxygenation is needed. Pulse oximetry is recommended to evaluate the need for oxygenation, but it is not clear whether peripheral perfusion is adequate for the evaluation of arterial oxygen saturation (SpO2 ). Additionally, there has been no study on the changes in SpO2 immediately after birth in Japan, despite the indispensable need for definitive oxygenation criteria. METHODS: A prospective observational study was performed in neonates at gestational age 35-41 weeks. An SpO2 measurement probe was attached to the neonates immediately after birth at the right palm or wrist, and the perfusion index (PI), pulse rate, and SpO2 were measured until 10 min after birth. RESULTS: Sixty neonates were examined. Stable PI was obtained soon after birth, preceding SpO2 measurement. The median PI (%) was constant at approximately 1.3, and the median SpO2 at 2-10 min was 70%, 81%, 82%, 87%, 89%, 92%, 92%, 94%, and 95%, respectively. The current target value for SpO2 in the Neonatal Cardiopulmonary Resuscitation (NCPR) guideline in Japan is approximately the 25th percentile. CONCLUSION: PI is stable and sufficient in the early postnatal period, meaning that peripheral perfusion is adequate for the measurement of SpO2 . The current target SpO2 used in the NCPR guidelines is at approximately the 25th percentile and is thought to be sufficient for meeting oxygenation criteria.

A Change in Ocular Circulation after Photocoagulation for Retinopathy of Prematurity in a Neonate.

BACKGROUND: The dilation of veins and tortuosity of arteries that occur in retinopathy of prematurity (ROP) are improved by therapy, and thus posttherapy changes in ocular circulation are also conceivable. We report a case of ROP in which we were able to measure the ocular circulation before and after photocoagulation therapy, using a laser speckle flowgraphy (LSFG) system that is modified for neonates. CASE REPORT: A female infant was born at 25 weeks' gestation with a birth weight of 808 g. We performed photocoagulation in both eyes at age 15 weeks, and we measured the ocular circulation with the "LSFG-baby" system before and at 12 weeks after the photocoagulation treatment. We also measured the mean blur rate (MBR) in the optic nerve head (ONH) and the relative flow volume (RFV) in the retinal vessels, and we examined the change rates from before to after treatment. The changing rate of the MBR-A (the mean of all values) in the ONH in the right and left eyes was 76.5 and 98.5%, respectively. The vascular RFV in the severe dilation and tortuosity quadrant also tended to decrease. CONCLUSIONS: Photocoagulation improved the dilation of veins and tortuosity of arteries and reduced the ocular blood flow in this neonate with ROP. The LSFG-baby system effectively and directly revealed the optic nerve and retinal blood vessels.

Nasopharynx is well-suited for core temperature measurement during hypothermia therapy.

BACKGROUND: Rectal temperature is commonly used as the core temperature during therapeutic hypothermia therapy in neonates with hypoxic-ischemic encephalopathy (HIE). The purpose of this study was to examine whether nasopharyngeal temperature could serve as a substitute for rectal temperature. METHODS: We prospectively investigated 40 neonates with HIE who underwent therapeutic hypothermia by selective head cooling, which involved cooling the body to 34°C for 72 h. During this period, nasopharyngeal temperature was measured and compared with rectal temperature every hour. RESULTS: For 40 neonates included in this study, the mean rectal and nasopharyngeal temperatures were 34.3 ± 0.4°C (n = 2920) and 34.3 ± 0.4°C (n = 2920), respectively. Nasopharyngeal temperature strongly correlated with rectal temperature (R2 = 0.623, P < 0.0001) and magnitude of the mean difference between nasopharyngeal and rectal temperature varied little during the 72 h of therapeutic hypothermia. CONCLUSIONS: Nasopharyngeal temperature in neonates with perinatal HIE undergoing therapeutic hypothermia may be a suitable substitute for rectal temperature.

Ocular blood flow values measured by laser speckle flowgraphy correlate with the postmenstrual age of normal neonates.

PURPOSE: To evaluate the relationships between optic nerve head (ONH) blood flow by laser speckle flowgraphy (LSFG), and postmenstrual age and body weight in normal neonates. METHODS: During their normal sleep, we studied 24 infants (postmenstrual age, 248-295 days) whose ocular blood flow could be measured three consecutive times. While the subjects slept in the supine position, three mean blur rate (MBR) values of the ONH were obtained: the MBR-A (mean of all values), MBR-V (vessel mean) and MBR-T (tissue mean) in the ONH. With regard to eye diseases, no retinopathy of prematurity (ROP) was observed, and no severe systemic diseases requiring treatment were noted in the subjects. Pearson's correlation coefficients were used to determine the relationship between the MBR-A, -V, -T and postmenstrual age (days) and body weight (g). RESULTS: Postmenstrual age was significantly correlated with MBR-A (r = 0.64, p = 0.0007), MBR-V (r = 0.62, p = 0.0012) and MBR-T (r = 0.62, p = 0.0012). However, the body weight was not correlated with the MBR (MBR-A: r = 0.37, p = 0.07, MBR-V: r = 0.31, p = 0.14, MBR-T: r = 0.38, p = 0.06). CONCLUSIONS: Our results clarified that the values of ocular blood flow measured by LSFG correlate with the postmenstrual age of normal neonates.

Residual blood volume in the umbilical cord of extremely premature infants.

BACKGROUND: The aim of this study was to investigate residual blood volume in the umbilical cord of extremely premature infants. METHODS: Twenty extremely premature infants were held at or below the placenta while the umbilical cord was clamped and cut at approximately 2-3 cm from the umbilicus within 30 s after birth. The umbilical cord was then clamped near the placenta to obtain a length of approximately 30 cm and cut. The residual blood volume in the segment of cord was drained and measured in milliliters. RESULTS: Mean birthweight was 846 ± 172 g (range, 587-1180 g). The average length of the clamped segment of umbilical cord was 29.8 ± 1.5 cm (range, 27-32 cm). Total residual blood volume and residual blood volume per cm were 15.5 ± 6.7 mL (range, 6-25 mL) and 0.5 ± 0.2 mL/cm (range, 0.2-0.8 mL/cm), respectively. The residual cord blood volume per kilogram of infant weight per 30 cm was 17.7 ± 5.5 mL/kg/30 cm (range, 8.9-29.0 mL/kg/30 cm). CONCLUSION: Infants could receive approximately 18 mL/kg of whole blood by one-time milking of 30 cm umbilical cord. With an average hematocrit of 40%, this volume is equivalent to approximately 13 mL of packed red blood cells (hematocrit 55%).