Cerebral perfusion and its relation with systemic circulation in extremely LBW (ELBW) infants in the early neonatal period are not well understood. The cerebral tissue oxygenation index (TOI) and cerebral fractional tissue oxygen extraction (FTOE) were monitored in stable 16 ELBW infants (GA Ͻ29 wk) using nearinfrared spectroscopy (NIRS) at 3-6, 12, 18, 24, 36, 48, and 72 h after birth. The left ventricular end-systolic wall stress (ESWS), left ventricular ejection fraction (LVEF), left ventricular cardiac output (LVCO), and superior vena cava (SVC) flow were also measured simultaneously using echocardiography. The ESWS increased till 18 h and then decreased; LVEF, LVCO, and SVC flow decreased till 12 h and increased thereafter. The TOI decreased till 12 h and correlated with SVC flow; FTOE increased until 12 h and then decreased. These changes in variables of NIRS and echocardiographic measurements contrasted to changes in mean arterial blood pressure (MABP), which showed trends of continuous and gradual increase after birth. We conclude that even stable ELBW infants undergo evident transitional changes in cerebral oxygenation and perfusion in the early postnatal period, which may reflect changes in cardiac function and cardiac output. T he survival rate of extremely LBW (ELBW) infants has markedly improved owing to advances in medical technology and patient management as well as better understanding of neonatal pathophysiology. However, cerebral complications remain a major problem causing long-term neurodevelopmental sequelae (1). Intraventricular hemorrhage (IVH) is known to occur in ELBW infants and is attributable to multiple pathogenetic factors including vulnerability of the vasculature and fragility of the germinal matrix of the brain (2). Hypotension and hypoperfusion of the brain during the immediate postnatal period have been reported to be related with cerebral damage in sick preterm infants (3-5). Kluckow and Evans (6) proposed Doppler echocardiographic measurement of blood flow in the superior vena cava (SVC) as a consistent marker of upper body perfusion, including cerebral blood flow (CBF). They reported that sick preterm infants who developed IVH experienced a period of low SVC flow within the first 48 h of life (7).Although some recent studies have found changes in cerebral oxygenation in very LBW (VLBW) infants (8,9) using near-infrared spectroscopy (NIRS), there have been no studies on longitudinal and detailed assessment of cerebral perfusion in ELBW infants in the early postnatal period. Furthermore, the relationship between cerebral perfusion, systemic perfusion, and arterial blood pressure during the immediate postnatal period is determined by multiple factors and has not been fully understood. The aim of this study was to characterize in detail the cerebral oxygenation and oxygen extraction, as determined by NIRS, and systemic blood flow and cardiac function, as evaluated by echocardiography, in ELBW infants during the early postnatal period. METHODSSubjects. ELBW infants (bir...

No abstract

No abstract

Background: The relationship between cerebral and peripheral hemodynamics during the early postnatal period has not been clarified. Objectives: To evaluate cerebral and peripheral oxygenation and blood volumes between term and preterm infants during the first 3 days of life. Materials and Methods: We performed near-infrared time-resolved spectroscopy on 32 term infants (term group) and 40 preterm infants (preterm group), with an optode placed on their forehead and upper arm. The cerebral blood volume (CBV), peripheral blood volume (PBV), cerebral Hb oxygen saturation (cSO₂) and peripheral Hb oxygen saturation (pSO₂) were measured at 3-6, 12, 24, 48 and 72 h after birth. Results: The CBV in the term group (2.45 ± 0.47 ml/100 g) was significantly higher than that in the preterm group (1.97 ± 0.33 ml/100 g). In contrast to the CBV, the PBV in the preterm group (3.63 ± 0.76 ml/100 g) was significantly higher than that in the term group (3.26 ± 0.56 ml/100 g). In the preterm group, there was a significant positive relationship between the CBVs and PBVs at each time point except at 72 h after birth. Despite the differences in blood volumes, there were no differences in the cSO₂ and pSO₂ between the two groups. Conclusions: The contrasting results in the CBV and PBV between the term and preterm infants might be explained by differences in the maturation of the physiological mechanism to control CBV and PBV.

Background: The Reiwa First Year East Japan Typhoon of 2019 caused a torrential flood in Japan. In Nagano City, a large area was flooded due to the collapse of the Chikuma River embankment. After largescale disasters, an increase in cardiovascular and cerebrovascular events has been reported on account of the stressful conditions. However, few reports of disaster-related diseases associated with flood damage have been described. Thus, our aim was to elucidate the effect of floods on the incidences of cardiovascular and cerebrovascular diseases in Nagano City. Methods: The Shinshu Assessment of Flood Disaster Cardiovascular Events (SAVE) trial enrolled 2,426 patients admitted for cardiovascular or cerebrovascular diseases at all five hospitals with an emergency department in Nagano City from October 1 to December 31 in the years 2017, 2018, and 2019. The occurrence of these diseases was calculated in every 2 weeks and the findings of 2019 (year of the flood) were compared with those of 2017 and 2018. Results: Cardiovascular and cerebrovascular diseases significantly increased during the 2 weeks immediately after the flood disaster (149 in 2019 vs average of 116.5 in the previous 2 years, p < 0.05). Unstable angina cases significantly increased 1.5-2 months after the flood disaster, and cerebral hemorrhage cases significantly increased in the 2 weeks after the flood disaster. Conclusions: Cardiovascular and cerebrovascular events increased significantly during the 2 weeks immediately after the large-scale flood disaster caused by the Reiwa First Year East Japan typhoon. Because of the increasing frequency of flood disasters, it is necessary to predict the occurrences of cardiovascular and cerebrovascular diseases and to implement guidelines for their appropriate and timely management.