Blood pressure variation with gestational age and birth weight in Indian newborn

Neonatal blood pressure by birth weight, gestational age, and postnatal age: a systematic review

BACKGROUND

Blood pressure is a vital hemodynamic marker during the neonatal period. However, normative values are often derived from small observational studies. Understanding the normative range would help to identify ideal thresholds for intervention to treat hypotension or hypertension. Therefore, the aim of this study was to assess observed blood pressure values in neonates who have not received any blood-pressure modifying treatments from birth to three months postnatal age and whether these vary according to birth weight, gestational age and postnatal age.

METHODS

This was a systematic review. A literature search was conducted in MEDLINE, PubMed, Embase, Cochrane Library, and CINAHL from 1946 to 2017 on blood pressure in neonates from birth to 3 months of age (PROSPERO ID CRD42018092886). Unpublished data were included where appropriate.

RESULTS

Of 3,587 non-duplicate publications identified, 30 were included (one unpublished study). Twelve studies contained data grouped by birth weight, while 23 contained data grouped by gestational age. Study and clinical heterogeneity precluded meta-analyses thus results are presented by subgroup. A consistent blood pressure rise was associated with increasing birth weight, gestational age, and postnatal age. In addition, blood pressure seemed to rise more rapidly in the most preterm and low birth weight neonates.

CONCLUSION

Despite blood pressure increasing with birth weight, gestational age, and postnatal age, there was marked blood pressure variability observed throughout. To better define hypotension and hypertension, future studies should develop consistent approaches for factors related to blood pressure variability, including the method and timing of measurement as well as statistical control of relevant patient characteristics.

Trajectory of Systemic Blood Pressure in Early Life: A Cohort Study

Objective. To track the BP (blood pressure) trajectory of healthy infants during the first year of life of healthy infants born in Northeast Brazil. Methods. In this cohort study, BP was assessed by oscillometry at the first 24 hours of life and 12 months of age. Results. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) increased with age (P < .001) and were not influenced by gender (SBP: P = .178 and DBP: P = .623) or type of delivery (SBP: P = .827 and DBP: P = .106), when compared between the first 24 hours of life and 12 months of age. Conclusion. The data from the present study increased knowledge about the trajectory of BP during the first year of life. The increase in BP between the first month and the first year of life was not influenced by gender or type of delivery.

Influence of Dorper lamb development from birth to 120 days of age on clinical and echocardiographic parameters

The expansion of the sheep model in research represents an attractive and economically beneficial academic reason for investigations in sheep echocardiography. The present study aimed to evaluate the clinical and echocardiographic parameters in Dorper lambs during the developmental period. Emphasis was placed on the use of the species in translational research for the echocardiographic diagnosis of congenital heart diseases, which can contribute to improvements in interventionist techniques. Ten Dorper lambs were evaluated at the following time points: 24 h after birth and 7, 14, 21, 30, 60, 90 and 120 days of age. Clinical parameters were compiled, and echocardiogram records were obtained without sedation. Rectal temperature was lower on the first day compared to the others. From 21 days of life, there was a reduction in HR, with differences between time points. Mean and systolic blood pressure differed, with the highest values at 90 and 120 days of age. The thickness of the interventricular septum in diastole (IVSd) increased as age progressed, with the highest value at 120 days of age, and the same occurred for LVIDd (left ventricle internal diameter in diastole), LVFWd (left ventricular free wall thickness in diastole), IVSs (interventricular septum thickness in systole), LVIDs (left ventricle internal diameter in systole) and LVFWs (left ventricular free wall thickness in systole). There were differences in the size of the LA, Ao and LA/Ao ratio, which were greater at 90 days and 120 days of age. Echocardiographic changes accompany the development of lambs, where changes in echocardiographic parameters are evident with advancing age. The echocardiographic measurements in lambs obtained in the present study are similar to those in newborns.

Blood Pressure Profile and Trends in the Neonatal Transitioning Period: A Comparative Study of Term Asphyxiated and Healthy Newborns

Background. Extra-uterine transition difficulties including BP abnormalities have been documented following perinatal asphyxia. Aim. The study aimed to determine the BP changes in the early neonatal transitioning period. Method. This comparative, cross-sectional study was conducted at the Ekiti State University Teaching Hospital, Ado-Ekiti, Nigeria. Result. A total of 246 term babies were analyzed. Their mean (standard deviation) systolic, diastolic and mean arterial blood pressures (SBP, DBP, and MBP) at birth were 68.2 (9.0), 39.9 (7.0), and 49.4 (6.9) mmHg and 67.4 (7.9), 37.1 (6.1), and 47.2 (5.8) mmHg, respectively. Asphyxiated neonates had significantly higher initial DBP (P < .001) and MAP (P = .008), lower SBP (P < .001) and MAP (P = .024) at 6 hours and lower SBP at 12 hours after birth, statistically. Conclusion. This study showed that while the BP of healthy neonates steadily increases in the first 48 hours after birth, it fluctuated markedly within the first 12 hours of birth among asphyxiated babies.

Risk Factors of Mechanical Ventilation in Premature Infants During Hospitalization

Background

The purpose of this study was to identify the risk factors for premature neonates requiring mechanical ventilation.

Methods

Premature neonates admitted to Chengdu Women’s and Children’s Central Hospital between July 2014 and December 2020 were retrospectively included in this study. Clinical and demographic factors were collated. Univariate and multivariate logistic regression analyses were conducted to identify the risk factors for premature infants requiring mechanical ventilation.

Results

A total of 1262 premature neonates participated in the study. Among them, 423 (33.53%) neonates required mechanical ventilation, whereas 839 (66.48%) neonates did not require mechanical ventilation. Multivariate logistic regression analysis determined that a lower Apgar score at 5 min (OR = 0.595, 95% CI: 0.472–0.74; P < 0.001), lower gestational age (very preterm) (OR = 11.745, 95% CI: 4.362, 31.619, P < 0.001), lower systolic blood pressure (OR = 0.864, 95% CI: 0.812–0.917, P = 0.001), lower diastolic blood pressure (OR = 0.894, 95% CI: 0.831–0.96, P = 0.002), higher respiratory rate (OR = 1.292, 95% CI: 1.238–1.355, P < 0.001), increased C-reactive protein levels (OR=1.044, 95% CI: 1.003–1.086, P = 0.036), and presence of patent ductus arteriosus (OR = 2.174, 95% CI: 1.185–3.972, P = 0.012) were independently associated with an increased possibility of adopting mechanical ventilation in premature infants. ROC analysis demonstrated that the predicted power for premature neonates requiring mechanical ventilation was 0.855 (95% CI: 0.808–0.902, P < 0.001).

Conclusion

In conclusion, we determined that a lower Apgar score at 5 min, lower gestational age, lower systolic blood pressure, lower diastolic blood pressure, higher respiratory rate, increased C-reactive protein levels and presence of patent ductus arteriosus were independently associated with an increased possibility of adopting mechanical ventilation in premature infants.

Blood pressure ranges via non-invasive and invasive monitoring techniques in premature neonates using high resolution physiologic data

BACKGROUND

There are limited evidence-based published blood pressure ranges for premature neonates. The aim of the study was to determine blood pressure ranges in a large cohort of premature neonates based on gestational and post-menstrual age.

METHODS

Retrospective observational study of premature neonates admitted to the neonatal intensive care unit at our institution between January 2009 and October 2015. We stratified data by gestational and post-menstrual age groups as well as by method of blood pressure measurement (non-invasive vs. invasive).

RESULTS

Over two billion blood pressure values in 1708 neonates were analyzed to generate heat maps and establish percentile-based reference ranges. The median gestational age of the cohort was 31 weeks (IQR 28-33 weeks). We found moderate correlation (r = 0.57) between simultaneously obtained non-invasive and invasive blood pressure measurements.

CONCLUSIONS

Our results can serve as a reference during the bedside assessment of the critically-ill neonate.

Comparison of Global DNA Methylation Patterns in Human Melanoma Tissues and Their Derivative Cell Lines

Simple Summary

Cancer cell lines are a defined population of cells, originally sourced from tumour tissue, that can be maintained in culture for an extended period of time. They are a critical laboratory-based model, and are frequently used to unravel mechanisms of cancer cell biology. In all cells, gene activity is in part regulated by DNA methylation, the epigenetic process by which methyl groups are added to DNA. In this study, we demonstrate that at a global level, DNA methylation profiles are globally well conserved, but we identify specific sites that are consistently more methylated in tumour-derived cell lines compared to the original tumour tissue. The genes associated with these common differentially methylated regions are involved in important cellular processes and are strongly enriched for epigenetic mechanisms associated with suppression of gene activity. This study provides a valuable resource for identifying false positives due to cell culture and for better interpretation of future cancer epigenetics studies.

Abstract

DNA methylation is a heritable epigenetic mark that is fundamental to mammalian development. Aberrant DNA methylation is an epigenetic hallmark of cancer cells. Cell lines are a critical in vitro model and very widely used to unravel mechanisms of cancer cell biology. However, limited data are available to assess whether DNA methylation patterns in tissues are retained when cell lines are established. Here, we provide the first genome-scale sequencing-based methylation map of metastatic melanoma tumour tissues and their derivative cell lines. We show that DNA methylation profiles are globally conserved in vitro compared to the tumour tissue of origin. However, we identify sites that are consistently hypermethylated in cell lines compared to their tumour tissue of origin. The genes associated with these common differentially methylated regions are involved in cell metabolism, cell cycle and apoptosis and are also strongly enriched for the H3K27me3 histone mark and PRC2 complex-related genes. Our data indicate that although global methylation patterns are similar between tissues and cell lines, there are site-specific epigenomic differences that could potentially impact gene expression. Our work provides a valuable resource for identifying false positives due to cell culture and for better interpretation of cancer epigenetics studies in the future.

Critical review of nutrition, blood pressure and risk of hypertension through the lifecycle: do B vitamins play a role?

Hypertension is the leading cause of preventable mortality worldwide, contributing to over 9 million deaths per annum, predominantly owing to cardiovascular disease. The association of obesity, physical inactivity and alcohol with elevated blood pressure (BP) is firmly established. Weight loss or other dietary strategies, such as the Dietary Approaches to Stop Hypertension (DASH) diet, have been shown to be effective in lowering BP. Additionally, specific nutrients are recognised to contribute to BP, with higher sodium intake linked with an increased risk of hypertension, while potassium is associated with a reduced risk of hypertension. Of note, emerging evidence has identified a novel role for one-carbon metabolism and the related B vitamins, particularly riboflavin, in BP. Specifically in adults genetically at risk of developing hypertension, owing to the common C677T polymorphism in MTHFR, supplemental riboflavin (co-factor for MTHFR) was shown in randomised trials to lower systolic BP by up to 13 mmHg. A BP response to intervention of this magnitude could have important clinical impacts, given that a reduction in systolic BP of 10 mmHg is estimated to decrease stroke risk by 40%. This review aims to explore the factors contributing to hypertension across the lifecycle and to critically evaluate the evidence supporting a role for nutrition, particularly folate-related B vitamins, in BP and risk of hypertension. In addition, gaps in our current knowledge that warrant future research in this area, will be identified.