New methods of differentiation between primary and secondary hypertension in a pediatric population: A single-center experience

BACKGROUND

Kidney diseases are the main causative factors of secondary hypertension (HTN) in children. Although primary HTN is less common in the pediatric population, its increasing prevalence, especially among teenagers, makes early diagnosis an emerging issue.

OBJECTIVES

To analyze the potential differences between primary HTN and HTN secondary to renal diseases, in order to tailor diagnostic procedures to pediatric patients with suspicion of HTN.

MATERIAL AND METHODS

A retrospective evaluation was performed of medical records of 168 children (aged from 1 month to 18 years) diagnosed with arterial HTN in the Pediatric Nephrology Department of Wroclaw Medical University (Poland). The comparative analysis concerned demographics, causes of HTN, clinical picture, laboratory tests, and parameters of ambulatory blood pressure monitoring (ABPM).

RESULTS

Out of 168 children, 47% were diagnosed with primary HTN and 53% with secondary renal HTN. The patients with primary HTN were significantly older than those with HTN secondary to renal disease. Among the children with primary HTN, 26% were overweight and 42% were obese; among those with renal HTN, the proportions were 16% and 19%, respectively. The patients with primary HTN had significantly higher body mass index (BMI) percentiles and z-scores, and tended toward higher pulse pressure (PP) values. In the group with secondary HTN, ABPM parameters of diastolic blood pressure (DBP) and total cholesterol were significantly elevated. The BMI z-scores correlated positively with PP in the whole group.

CONCLUSIONS

As expected, HTN secondary to renal disease prevails in younger children, but primary HTN has become an emerging issue in teenagers. The diagnostics of HTN secondary to kidney disease have revealed risk factors worsening the prognosis, including higher values of cholesterol or of parameters connected with DBP. Primary HTN risk factors include obesity and a tendency towards higher PP values.

Caffeic and chlorogenic acids modulate altered activity of key enzymes linked to hypertension in cyclosporine-induced hypertensive rats

OBJECTIVES

This study aimed to explore the protective mechanism of caffeic acid (CAA) and chlorogenic acid (CHA) on cyclosporine (CSA) induced hypertensive rats.

METHODS

Effect of CAA and CHA on diastolic blood pressure (DBP), mean arterial pressure (MAP), angiotensin-converting enzyme (ACE), e-nucleotide triphosphate dephosphorylase (e-NTPDase), 5' nucleotidase and adenosine deaminase (ADA) activity in CSA-induced hypertensive rats were determined.

RESULTS

CAA and CHA administration stabilized hypertensive effect caused by CSA administration. Also, altered activity of ACE (lung), e-NTPDase, 5' nucleotidase, ADA as well as elevated malondiadehyde (MDA) level was restored in all the treated hypertensive rats in comparison with the untreated hypertensive rats.

CONCLUSION

Hence, these observed results could underlie some of the mechanisms through which CAA and CHA could offer antihypertensive effect.

Study for Improving Maternal Pregnancy And Child ouTcomes (IMPACT): a study protocol for a Swedish prospective multicentre cohort study

INTRODUCTION

First-trimester pregnancy risk evaluation facilitates individualised antenatal care, as well as application of preventive strategies for pre-eclampsia or birth of a small for gestational age infant. A range of early intervention strategies in pregnancies identified as high risk at the end of the first trimester has been shown to decrease the risk of preterm pre-eclampsia (<37 gestational weeks). The aim of this project is to create the Improving Maternal Pregnancy And Child ouTcomes (IMPACT) database; a nationwide database with individual patient data, including predictors recorded at the end of the first trimester and later pregnancy outcomes, to identify women at high risk of pre-eclampsia. A second aim is to link the IMPACT database to a biobank with first-trimester blood samples.

METHODS AND ANALYSIS

This is a Swedish prospective multicentre cohort study. Women are included between the 11th and 14th weeks of pregnancy. At inclusion, pre-identified predictors are retrieved by interviews and medical examinations. Blood samples are collected and stored in a biobank. Additional predictors and pregnancy outcomes are retrieved from the Swedish Pregnancy Register. Inclusion in the study began in November 2018 with a targeted sample size of 45 000 pregnancies by end of 2021. Creation of a new risk prediction model will then be developed, validated and implemented. The database and biobank will enable future research on prediction of various pregnancy-related complications.

ETHICS AND DISSEMINATION

Confidentiality aspects such as data encryption and storage comply with the General Data Protection Regulation and with ethical committee requirements. This study has been granted national ethical approval by the Swedish Ethical Review Authority (Uppsala 2018-231) and national biobank approval at Uppsala Biobank (18237 2 2018 231). Results from the current as well as future studies using information from the IMPACT database will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03831490.

Screening for pre-eclampsia at 11-13 weeks' gestation: use of pregnancy-associated plasma protein-A, placental growth factor or both

OBJECTIVE

First-trimester screening for pre-eclampsia (PE) is useful because treatment of the high-risk group with aspirin reduces the rate of early PE with delivery at < 34 weeks' gestation by about 80% and that of preterm PE with delivery at < 37 weeks by 60%. In previous studies, we reported that the best way of identifying the high-risk group is by a combination of maternal factors, mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and serum placental growth factor (PlGF). An alternative biochemical marker is pregnancy-associated plasma protein-A (PAPP-A), which is used widely as part of early screening for trisomy. The objective of this study was to examine the additive value of PlGF and PAPP-A in first-trimester screening for preterm PE by maternal factors, MAP and UtA-PI and define the risk cut-off and screen-positive rate to achieve a desired detection rate of PE if PAPP-A rather than PlGF was to be used for first-trimester screening.

METHODS

This was a non-intervention screening study. The data were derived from prospective screening for adverse obstetric outcomes in women with singleton pregnancy attending for a routine first-trimester hospital visit. Patient-specific risks of delivery with PE at < 37 weeks' gestation were calculated using the competing-risks model to combine the prior distribution of gestational age at delivery with PE, obtained from maternal characteristics and medical history, with multiples of the median (MoM) values of MAP, UtA-PI, PlGF and PAPP-A. The performance of screening in the total population and in subgroups of women of white and black racial origin was estimated. McNemar's test was used to compare the detection rate, for a fixed screen-positive rate, of screening with and without PlGF and PAPP-A. Risk cut-offs and screen-positive rates to achieve desired detection rates of preterm PE were determined in screening with and without PlGF and PAPP-A.

RESULTS

The study population was composed of 60 875 singleton pregnancies, including 1736 (2.9%) that developed PE. There are three main findings of this study. First, the performance of first-trimester screening for PE by a combination of maternal factors, MAP, UtA-PI and PlGF is superior to that of screening by maternal factors, MAP, UtA-PI and PAPP-A; for example, in screening by maternal factors, MAP, UtA-PI and PlGF, at a screen-positive rate of 10%, the detection rate of PE with delivery at < 37 weeks' gestation was 74.1%, which was 7.1% (95% CI, 3.8-10.6%) higher than in screening by maternal factors, MAP, UtA-PI and PAPP-A. Second, addition of serum PAPP-A does not improve the prediction of PE provided by maternal factors, MAP, UtA-PI and PlGF. Third, the risk cut-off and screen-positive rate to achieve a given fixed detection rate of preterm PE vary according to the racial composition of the study population and whether the biomarkers used for screening are MAP, UtA-PI and PlGF or MAP, UtA-PI and PAPP-A. For example, in screening by a combination of maternal factors, MAP, UtA-PI and PlGF in white women, if the desired detection rate of preterm PE was 75%, the risk cut-off should be 1 in 136 and the screen-positive rate would be 14.1%; in black women, to achieve a detection rate of 75%, the risk cut-off should be 1 in 29 and the screen-positive rate would be 12.5%. In screening by a combination of maternal factors, MAP, UtA-PI and PAPP-A in white women, if the desired detection rate of preterm PE was 75%, the risk cut-off should be 1 in 140 and the screen-positive rate would be 16.9%; in black women, to achieve a detection rate of 75%, the risk cut-off should be 1 in 44 and the screen-positive rate would be 19.3%.

CONCLUSION

In first-trimester screening for PE, the preferred biochemical marker is PlGF rather than PAPP-A. However, if PAPP-A was to be used rather than PlGF, the same detection rate can be achieved but at a higher screen-positive rate. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Exaggerated blood pressure response to exercise is associated with subclinical vascular impairment in healthy normotensive individuals

BACKGROUND

This study was designed to evaluate the possible association between an exaggerated blood pressure (BP) response to exercise and subclinical vascular impairment in normotensive individuals.

METHODS

The study participants consisted of 92 untreated normotensive men (aged 42 ± 9 years) without a history of cardiovascular disease or stroke. A graded exercise test was conducted using a bicycle ergometer, and the mean arterial pressure (MAP) during submaximal exercise was evaluated. The brachial-ankle pulse wave velocity (baPWV) was measured as an index of arterial stiffness. The second peak of radial systolic BP (SBP2) was used as an estimate of central BP. The albumin-to-creatinine ratio (ACR) values were determined as the mean of two nonconsecutive spot urine specimens.

RESULTS

Compared with individuals with a normal response (MAP z-score < +1.0, n = 60), those with an exaggerated BP response to exercise (MAP z-score ≥ +1.0, n = 32) exhibited significantly higher baPWV (1412 ± 158 vs. 1250 ± 140 cm/s), radial SBP2 (122 ± 11 vs. 106 ± 13 mmHg), and greater log-ACR (0.93 ± 0.30 vs. 0.59 ± 0.23 mg/gCre). Multiple regression analysis revealed that an exaggerated BP response to exercise was significantly associated with baPWV (β = 0.198, P= .043), radial SBP2 (β = 0.156, P = .049), and log-ACR (β = 0.276, P = .006) independent of potential confounding factors.

CONCLUSIONS

These results suggest that subclinical vascular impairment is associated with an exaggerated increase in BP during exercise even in the absence of clinical hypertension.

First-trimester pre-eclampsia biomarker profiles in Asian population: multicenter cohort study

OBJECTIVES

To (i) evaluate the applicability of the European-derived biomarker multiples of the median (MoM) formulae for risk assessment of preterm pre-eclampsia (PE) in seven Asian populations, spanning the east, southeast and south regions of the continent, (ii) perform quality-assurance (QA) assessment of the biomarker measurements and (iii) establish criteria for prospective ongoing QA assessment of biomarker measurements.

METHODS

This was a prospective, non-intervention, multicenter study in 4023 singleton pregnancies, at 11 to 13 + 6 weeks' gestation, in 11 recruiting centers in China, Hong Kong, India, Japan, Singapore, Taiwan and Thailand. Women were screened for preterm PE between December 2016 and June 2018 and gave written informed consent to participate in the study. Maternal and pregnancy characteristics were recorded and mean arterial pressure (MAP), mean uterine artery pulsatility index (UtA-PI) and maternal serum placental growth factor (PlGF) were measured in accordance with The Fetal Medicine Foundation (FMF) standardized measurement protocols. MAP, UtA-PI and PlGF were transformed into MoMs using the published FMF formulae, derived from a largely Caucasian population in Europe, which adjust for gestational age and covariates that affect directly the biomarker levels. Variations in biomarker MoM values and their dispersion (SD) and cumulative sum tests over time were evaluated in order to identify systematic deviations in biomarker measurements from the expected distributions.

RESULTS

In the total screened population, the median (95% CI) MoM values of MAP, UtA-PI and PlGF were 0.961 (0.956-0.965), 1.018 (0.996-1.030) and 0.891 (0.861-0.909), respectively. Women in this largely Asian cohort had approximately 4% and 11% lower MAP and PlGF MoM levels, respectively, compared with those expected from normal median formulae, based on a largely Caucasian population, whilst UtA-PI MoM values were similar. UtA-PI and PlGF MoMs were beyond the 0.4 to 2.5 MoM range (truncation limits) in 16 (0.4%) and 256 (6.4%) pregnancies, respectively. QA assessment tools indicated that women in all centers had consistently lower MAP MoM values than expected, but were within 10% of the expected value. UtA-PI MoM values were within 10% of the expected value at all sites except one. Most PlGF MoM values were systematically 10% lower than the expected value, except for those derived from a South Asian population, which were 37% higher.

CONCLUSIONS

Owing to the anthropometric differences in Asian compared with Caucasian women, significant differences in biomarker MoM values for PE screening, particularly MAP and PlGF MoMs, were noted in Asian populations compared with the expected values based on European-derived formulae. If reliable and consistent patient-specific risks for preterm PE are to be reported, adjustment for additional factors or development of Asian-specific formulae for the calculation of biomarker MoMs is required. We have also demonstrated the importance and need for regular quality assessment of biomarker values. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Mean arterial pressure is associated with the neurological function in patients who survived after cardiopulmonary resuscitation: A retrospective cohort study

Background

About 18% to 40% of the survivors have moderate to severe neurological dysfunction. At present, studies on mean arterial pressure (MAP) and neurological function of patients survived after cardiopulmonary resuscitation (CPR) are limited and conflicted.

Hypothesis

The higher the MAP of the patient who survived after CPR, the better the neurological function.

Method

A retrospective cohort study was conducted to detect the relationship between MAP and the neurological function of patients who survived after CPR by univariate analysis, multivariate regression analysis, and subgroup analysis.

Results

From January 2007 to December 2015, a total of 290 cases met the inclusion criteria and were enrolled in this study. The univariate analysis showed that MAP was associated with the neurological function of patients who survived after CPR; its OR value was 1.03 (1.01, 1.04). The multi‐factor regression analysis also showed that MAP was associated with the neurological function of patients survived after CPR in the four models, the adjusted OR value of the four models were 1.021 (1.008, 1.035); 1.028 (1.013, 1.043); 1.027 (1.012, 1.043); and 1.029 (1.014, 1.044), respectively. The subgroups analyses showed that when 65 mm Hg ≤ MAP<100 mm Hg and when patients with targeted temperature management or without extracorporeal membrane oxygenation, with the increase of MAP, the better neurological function of patients survived after CPR.

Conclusion

This study found that the higher MAP, the better the neurological function of patients who survived after CPR. At the same time, the maintenance of MAP at 65 to 100 mm Hg would improve the neurological function of patients who survived after CPR.

Evaluating the clinical and cost-effectiveness of permissive hypotension in critically ill patients aged 65 years or over with vasodilatory hypotension: Statistical and health economic analysis plan for the 65 trial in article

The 65 trial is a pragmatic, multicentre, parallel-group, open-label, randomised clinical trial of permissive hypotension (targeting a mean arterial pressure target of 60-65 mmHg during vasopressor therapy) versus usual care in critically ill patients aged 65 years or over with vasodilatory hypotension. The trial will recruit 2600 patients from 65 United Kingdom adult general critical care units. The primary outcome is all-cause mortality at 90 days. An economic evaluation is embedded. This paper describes the proposed statistical and health economic analysis for the 65 trial.

The competing risk approach for prediction of preeclampsia

The established method of the assessment of the risk for development of preeclampsia is to identify risk factors from maternal demographic characteristics and medical history; in the presence of such factors, the patient is classified as high risk and in their absence as low risk. Although this approach is simple to perform, it has poor performance of the prediction of preeclampsia and does not provide patient-specific risks. This review describes a new approach that allows the estimation of patient-specific risks of delivery with preeclampsia before any specified gestational age by maternal demographic characteristics and medical history with biomarkers obtained either individually or in combination at any stage in pregnancy. In the competing risks approach, every woman has a personalized distribution of gestational age at delivery with preeclampsia; whether she experiences preeclampsia or not before a specified gestational age depends on competition between delivery before or after the development of preeclampsia. The personalized distribution comes from the application of Bayes theorem to combine a previous distribution, which is determined from maternal factors, with likelihoods from biomarkers. As new data become available, what were posterior probabilities take the role as the previous probability, and data collected at different stages are combined by repeating the application of Bayes theorem to form a new posterior at each stage, which allows for dynamic prediction of preeclampsia. The competing risk model can be used for precision medicine and risk stratification at different stages of pregnancy. In the first trimester, the model has been applied to identify a high-risk group that would benefit from preventative therapeutic interventions. In the second trimester, the model has been used to stratify the population into high-, intermediate-, and low-risk groups in need of different intensities of subsequent monitoring, thereby minimizing unexpected adverse perinatal events. The competing risks model can also be used in surveillance of women presenting to specialist clinics with signs or symptoms of hypertensive disorders; combination of maternal factors and biomarkers provide patient-specific risks for preeclampsia that lead to personalized stratification of the intensity of monitoring, with risks updated on each visit on the basis of biomarker measurements.

[Cerebral Autoregulation in Patients with Unilateral Carotid Artery Stenosis]

Objective To investigate cerebral autoregulation(CA)in patients with severe unilateral carotid artery stenosis by near infrared spectroscopy. Methods Thirty patients who underwent general anesthesia in our hospital from January 2015 to February 2017 were enrolled in this study.The stenosis group included 15 patients with severe unilateral internal carotid artery stenosis,and the control group included 15 patients without carotid artery stenosis.Both groups were matched in sex and age.Cerebral tissue oxygenation index(TOI)and mean arterial pressure were recorded continuously under stable general anesthesia.The Pearson correlation coefficient(r)was calculated to judge the CA status. Results TOI was not significantly different between the stenosis side and the non-stenosis side in the stenosis group(66.52±6.50 vs. 65.23±4.50;t=0.93, P=0.368)or between the stenosis side in the stenosis group and the stenosis side in the control group(66.52±6.50 vs. 64.22±3.87;t=1.18, P=0.248).The r values of stenosis side and non-stenosis side in the stenosis group were 0.36±0.12 and 0.17±0.11,respectively,and the r values of the stenosis side in the stenosis group and the stenosis side of the control group were 0.36±0.12 and 0.13±0.08,respectively.In the stenosis group,5 patients had transient ischemic attack and 2 patients had a history of stroke within 3 months before operation.When an r value of 0.342 was used as the judgment point of CA abnormality,the sensitivity and specificity were 0.625 and 0.909,respectively. Conclusion Within the range of normal blood pressure fluctuation,cerebral blood flow is linked to blood pressure at the stenosis side in patients with severe unilateral carotid artery stenosis.

Non-invasive Assessment of Central Retinal Artery Pressure: Age and Posture-dependent Changes

Purpose: Assessment of Ocular Perfusion Pressure (OPP) requires estimation of the Mean Central Retinal Artery Pressure (MCRAP) [OPP = MCRAP-IOP]. In a seated position, MCRAP is currently estimated as 2/3 of the Mean Arterial Pressure (MAP) to account for the hydrostatic reduction of MAP at eye level. We tested a surrogate method for direct MCRAP assessment by measuring MAP with Arm-Up and cuff at eye level (AUMAP) at different postures and ages. Methods: MAP and AUMAP were assessed in a mixed population of 136 subjects (mean age 44 ± 17.39 years) including healthy participants (N = 30) and patients with optic neuropathies (Glaucoma suspects, N = 14; Open-Angle Glaucoma, N = 26, LHON, N = 19; MS, N = 47) not expected to alter systemic blood pressure. None of the subjects had history of carotid stenosis or pharmacological treatment to regulate blood pressure. AUMAP was also tested in two subgroups in supine (N = 42) and -10° Head Down body Tilt position (HDT, N = 46). Results: In the seated position, both 2/3MAP and AUMAP increased with increasing age, however with steeper (2x) slope for AUMAP (P < .0001). With decreasing angle of body tilt, AUMAP increased while MAP decreased. The mean AUMAP/MAP ratio (posture coefficient) was, seated, 0.73 (SE 0.003); supine, 0.90 (SE 0.005); HDT, 0.97 (SE 0.005). In the seated position only, the AUMAP/MAP ratio significantly increased with age (P < .0001). Mean posture coefficients obtained with AUMAP were in the range of those based on either direct ophthalmodynamometric measurements or hydrostatic estimations. Conclusions: Surrogate measurement of MCRAP in individual subjects is feasible using the simple AUMAP approach that provides a straightforward estimation of OPP (OPP = AUMAP - IOP) at different body postures. The standard method OPP = 2/3*MAP-IOP in the seated posture underestimates OPP at older ages. Clinical estimation of OPP would benefit from the use of AUMAP, in particular for head-down postures.

Placental function and fetal weight are associated with maternal hemodynamic indices in uncomplicated pregnancies at 35-37 weeks of gestation

BACKGROUND

Over the years, there has been an increasing interest in the assessment of maternal hemodynamic responses during pregnancy. With the use of both noninvasive devices and/or maternal echocardiography, it has been shown that mothers who have pregnancy complications have altered hemodynamics compared with those who have uncomplicated pregnancies. It also has been suggested that preexisting maternal cardiac changes might drive the development of complications in pregnancy that are associated with impaired placentation. To understand, however, this potential link in complicated pregnancies, it is important to clarify whether placental function is associated with maternal cardiac functional indices in normal pregnancies.

OBJECTIVE

To determine whether placental function, perfusion, and fetal weight are associated with maternal cardiac hemodynamic responses at 35-36 weeks of gestation in normal pregnancies.

STUDY DESIGN

Prospective screening of women attending Kings' College Hospital for routine hospital visit at 35-37 weeks' gestation. We recorded maternal characteristics and measured mean arterial pressure, uterine artery pulsatility index, sonographic estimated fetal weight, and serum placental growth factor and soluble fms-like tyrosine kinase 1. We also performed maternal echocardiogram to assess cardiac output and peripheral vascular resistance as well as indices of diastolic and systolic function, including global longitudinal systolic function and left ventricular mass indexed to body surface area.

RESULTS

We studied 1386 women. Maternal characteristics were associated with both maternal hemodynamics and functional and structural indices. Uterine artery pulsatility index was associated with left ventricular mass (P=.03) and global longitudinal systolic function (P=.017). There were significant nonlinear associations between placental growth factor and cardiac output and peripheral vascular resistance (P<.001 for both) and between soluble fms-like tyrosine kinase 1 and peripheral vascular resistance (P=.018). Estimated fetal weight was associated with maternal cardiac output (mean increase=0.186, 95% confidence interval, 0.133-0.238, P<.001) and peripheral vascular resistance (mean decrease=-0.164, 95% confidence interval, -0.217 to -0.111, P<.001). No association was noted between placental and fetal parameters and maternal cardiac functional and structural indices. In multivariable analysis, placental growth factor remained strongly associated with maternal cardiac output and peripheral vascular resistance (P=.002 for both) over and above maternal characteristics and estimated fetal weight. Estimated fetal weight was associated with left ventricular mass (0.102, 95% confidence interval, 0.044-0.162, P=.001).

CONCLUSION

The results of this study suggest a strong link between maternal hemodynamic responses and fetoplacental needs across the whole spectrum in normal pregnancies. These findings would also indicate that to diagnose maternal cardiac dysfunction in pregnancies complicated by impaired placentation a more extensive echocardiographic assessment might be needed rather than relying on hemodynamics which are strongly associated with fetoplacental indices.

A new model for screening for early-onset preeclampsia

BACKGROUND

Early identification of women with an increased risk for preeclampsia is of utmost importance to minimize adverse perinatal events. Models developed until now (mainly multiparametric algorithms) are thought to be overfitted to the derivation population, which may affect their reliability when applied to other populations. Options allowing adaptation to a variety of populations are needed.

OBJECTIVE

The objective of the study was to assess the performance of a first-trimester multivariate Gaussian distribution model including maternal characteristics and biophysical/biochemical parameters for screening of early-onset preeclampsia (delivery <34 weeks of gestation) in a routine care low-risk setting.

STUDY DESIGN

Early-onset preeclampsia screening was undertaken in a prospective cohort of singleton pregnancies undergoing routine first-trimester screening (8 weeks 0/7 days to 13 weeks 6/7 days of gestation), mainly using a 2-step scheme, at 2 hospitals from March 2014 to September 2017. A multivariate Gaussian distribution model including maternal characteristics (a priori risk), serum pregnancy-associated plasma protein-A and placental growth factor assessed at 8 weeks 0/7 days to 13 weeks 6/7 days and mean arterial pressure and uterine artery pulsatility index measured at 11.0-13.6 weeks was used.

RESULTS

A total of 7908 pregnancies underwent examination, of which 6893 were included in the analysis. Incidence of global preeclampsia was 2.3% (n = 161), while of early-onset preeclampsia was 0.2% (n = 17). The combination of maternal characteristics, biophysical parameters, and placental growth factor showed the best detection rate, which was 59% for a 5% false-positive rate and 94% for a 10% false-positive rate (area under the curve, 0.96, 95% confidence interval, 0.94-0.98). The addition of placental growth factor to biophysical markers significantly improved the detection rate from 59% to 94%.

CONCLUSION

The multivariate Gaussian distribution model including maternal factors, early placental growth factor determination (at 8 weeks 0/7 days to 13 weeks 6/7 days), and biophysical variables (mean arterial pressure and uterine artery pulsatility index) at 11 weeks 0/7 days to 13 weeks 6/7 days is a feasible tool for early-onset preeclampsia screening in the routine care setting. Performance of this model should be compared with predicting models based on regression analysis.

Cerebral oxygen desaturation in patients with totally thoracoscopic ablation for atrial fibrillation: A prospective observational study

BACKGROUND

Epicardial radiofrequency ablation for stand-alone atrial fibrillation under total video-assisted thoracoscopy has gained popularity in recent years. However, severe cardiopulmonary disturbances during the surgery may affect cerebral perfusion and oxygenation. We therefore hypothesized that regional cerebral oxygen saturation (rSO2) would decrease significantly during the surgery. In addition, the influencing factors of rSO2 would be investigated.

METHODS

A total of 60 patients scheduled for selective totally thoracoscopic ablation for stand-alone atrial fibrillation were enrolled in this prospective observational study. The rSO2 was monitored at baseline (T0), 15 min after anesthesia induction (T1), 15 minute after 1-lung ventilation (T2), after right pulmonary vein ablation (T3), after left pulmonary vein ablation (T4) and 15 minute after 2-lung ventilation (T5) using a near-infrared reflectance spectroscopy -based cerebral oximeter. Arterial blood gas was analyzed using an ABL 825 hemoximeter. Associations between rSO2 and hemodynamic or blood gas parameters were determined with univariate and multivariate linear regression analyses.

RESULTS

The rSO2 decreased greatly from baseline 65.4% to 56.5% at T3 (P < .001). Univariate analyses showed that rSO2 correlated significantly with heart rate (r = -0.173, P = .186), mean arterial pressure (MAP, r = 0.306, P = .018), central venous pressure (r = 0.261, P = .044), arterial carbon dioxide tension (r = -0.336, P = .009), arterial oxygen pressure (PaO2, r = 0.522, P < .001), and base excess (BE, r = 0.316, P = .014). Multivariate linear regression analyses further showed that it correlated positively with PaO2 (β = 0.456, P < .001), MAP (β = 0.251, P = .020), and BE (β = 0.332, P = .003).

CONCLUSION

Totally thoracoscopic ablation for atrial fibrillation caused a significant decrease in rSO2. There were positive correlations between rSO2 and PaO2, MAP, and BE.

Mechanisms involved in the cardiovascular effects caused by acute osmotic stimulation in conscious rats

Both the autonomic nervous system and the neuroendocrine system are activated by osmotic stimulation (OS) evoking cardiovascular effects. The current study investigated the mechanisms involved in the cardiovascular responses evoked by an acute osmotic stimulus with intraperitoneal (i.p.) injection of either isotonic (0.15 M NaCl) or hypertonic saline (0.6 M NaCl) in conscious rats. Hypertonic saline increased mean arterial pressure (MAP) and heart rate (HR) for 30 min, as well as plasma osmolality and sodium content. Urinary sodium and urinary volume were also increased. Pretreatment with the ganglion blocker pentolinium (i.v.) did not affect the pressor response, but significantly decreased the tachycardic response caused by OS. Pretreatment with the V₁-vasopressin receptor antagonist dTyr(CH₂)₅(Me)AVP (i.v.) reduced the pressor response, without affecting the tachycardic response evoked by the hypertonic OS. Neither the pressor nor the tachycardic response to OS was affected by pretreatment with either the oxytocin receptor antagonist atosiban or the α1-antagonist prazosin. Pretreatment with the β1-antagonist atenolol had no effect on the pressor response, but markedly decreased the tachycardic response evoked by OS. Results indicate that i.p. hypertonic OS-evoked pressor response is mediated by the release of vasopressin, with a minor influence of the vascular sympathetic input.LAY SUMMARYIncreased plasma osmolality, such as that observed during dehydration or salt intake, is a potent stimulus yielding to marked cardiovascular and neuroendocrine responses. The intraperitoneal (i.p.) injection of hypertonic saline solution is a commonly used animal model to cause a sustained increase in plasma osmolality, leading to a cardiovascular response characterized by sustained blood pressure and heart increases, whose systemic mechanisms were presently studied. Our findings indicate that the pressor response to the i.p. osmotic stimulus (OS) is mediated mainly by the release of vasopressin into the blood circulation with a minor or even the noninvolvement of the vascular sympathetic nervous system, whereas activation of the sympathetic-cardiac system mediates the tachycardic response to OS.

Effects of combined histamine H1 and H2 receptor blockade on hemodynamic responses to dynamic exercise in males with high-normal blood pressure

While postexercise hypotension is associated with histamine H₁ and H₂ receptor-mediated postexercise vasodilation, effects of histaminergic vasodilation on blood pressure (BP) in response to dynamic exercise are not known. Thus, in 20 recreationally active male participants (10 normotensive and 10 with high-normal BP) we examined the effects of histamine H₁ and H₂ receptor blockade on cardiac output (CO), mean atrial pressure (MAP), aortic stiffness (AoStiff), and total vascular conductance (TVC) at rest and during progressive cycling exercise. Compared with the normotensive group, MAP, CO, and AoStiff were higher in the high-normal group before and after the blockade at rest, while TVC was similar. At the 40% workload, the blockade significantly increased MAP in both groups, while no difference was found in the TVC. CO was higher in the high-normal group than the normotensive group in both conditions. At the 60% workload, the blockade substantially increased MAP and decreased TVC in the normotensive group, while there were no changes in the high-normal group. A similar CO response pattern was observed at the 60% workload. These findings suggest that the mechanism eliciting an exaggerated BP response to exercise in the high-normal group may be partially due to the inability of histamine receptors. Novelty Males with high-normal BP had an exaggerated BP response to exercise. The overactive BP response is known due to an increase in peripheral vasoconstriction. Increase in peripheral vasoconstriction is partially due to inability of histamine receptors.

Optimal Mean Arterial Pressure Within 24 Hours of Admission for Patients With Intermediate-Risk and High-Risk Pulmonary Embolism

We aimed to determine whether the average mean arterial pressure (aMAP) in the first 24 hours of hospital admission is useful in predicting short-term outcomes of patients with intermediate- and high-risk pulmonary embolism (PE). We conducted a single-center retrospective study. From May 2012 to April 2019, 122 patients with intermediate- and high-risk PE were included. The primary outcome was in-hospital mortality. The secondary outcome was adverse events. Receiver operating characteristic (ROC) curves and cutoff values for aMAP predicting in-hospital death were computed. According to cutoff values, we categorized 5 groups defined as follows: group 1: aMAP < 70 mm Hg; group 2: 70 mm Hg ≤ aMAP < 80 mm Hg; group 3: 80 mm Hg ≤ aMAP < 90 mm Hg; group 4: 90 mm Hg ≤ aMAP <100 mm Hg; and group 5: aMAP ≥ 100 mm Hg. Cox regression models were calculated to investigate associations between aMAP and in-hospital death. In the study group of 122 patients, 15 (12.30%) patients died in the hospital due to PE. The ROC analysis for MAP predicting in-hospital death revealed an area under the curve of 0.729 with a cutoff value of 79.4 mm Hg. Cox regression models showed a significant association between in-hospital death and aMAP group 1 (ref), aMAP group 2 (odds ratio [OR] = 1.680, 95% CI: 0.020-140.335), aMAP group 3 (OR = 0.003, 95% CI: 0.0001-0.343), aMAP group 4 (OR = 0.006, 95% CI: 0.0001-1.671), and aMAP group 5 (OR = 0.003, 95% CI: 0.0001-9.744). In particular, those with an aMAP of 80 to 90 mm Hg had minimum adverse events. The optimal range of MAP for patients with intermediate- and high-risk PE may be 80 to 90 mm Hg.

Augmented pressor and sympathoexcitatory responses to the onset of isometric handgrip in patients with type 2 diabetes

Patients with type 2 diabetes (T2D) exhibit greater daytime blood pressure (BP) variability, increasing their cardiovascular risk. Given the number of daily activities that incorporate short-duration isometric muscle contractions (e.g., carrying groceries), herein we investigated BP and muscle sympathetic nerve activity (MSNA) responses at the onset of isometric handgrip (HG). We tested the hypothesis that, relative to control subjects, patients with T2D would exhibit exaggerated pressor and MSNA responses to the immediate onset of HG. Mean arterial pressure (MAP) and MSNA were quantified during the first 30 s of isometric HG at 30% and 40% of maximal voluntary contraction (MVC) and during a cold pressor test (CPT), a nonexercise sympathoexcitatory stimulus. The onset of 30% MVC HG evoked similar increases in MAP between groups (P = 0.17); however, the increase in MSNA was significantly greater in patients with T2D versus control subjects with the largest group difference at 20 s (P < 0.001). At the onset of 40% MVC HG, patients with T2D demonstrated greater increases in MAP (e.g., 10 s, T2D: 9 ± 1 mmHg, controls: 5 ± 2 mmHg; P = 0.04). MSNA was also greater in patients with T2D at 40% MVC onset but differences were only significant at the 20-30 s timepoint (T2D: 15 ± 3 bursts/min, controls: -2 ± 4 bursts/min; P < 0.001). Similarly, MAP and MSNA responses were augmented during the onset of CPT in T2D patients. These findings demonstrate exaggerated pressor and MSNA reactivity in patients with T2D, with rapid and robust responses to both isometric contractions and cold stress. This hyper-responsiveness may contribute to daily surges in BP in patients with T2D, increasing their short-term and long-term cardiovascular risk.

The Effect of Candesartan Alone and Its Combination With Estrogen on Post-traumatic Brain Injury Outcomes in Female Rats

Aim: The aim of this study was to evaluate the effect of candesartan (angiotensin II type I receptor blocker) alone and its combination with estrogen on the changes in brain edema, intracranial pressure (ICP), and cerebral perfusion pressure (CPP) following diffuse traumatic brain injury (TBI) in female rats.

Methods: TBI was induced in ovariectomized female rats using Marmarou's method. The treatment groups received low-dose (LC) and high-dose (HC) candesartan, estrogen (E2), a combination of estrogen vehicle and candesartan vehicle (oil + vehicle), or a combination of estrogen with low-dose (E2 + LC), or with high-dose (E2 + HC) candesartan. ICP and CPP were measured before and several times after TBI, and the brain water content (brain edema) was measured 24 h after TBI.

Results: After the TBI, brain edema and ICP in the estrogen group were lower than in the vehicle and TBI groups. Brain edema and ICP in the HC group were lower than in the vehicle group after TBI. Although there was no significant difference in brain edema and ICP between the LC and vehicle groups, significant differences in these variables were observed when the E2 + LC and E2 + HC groups were compared with the oil + vehicle group after TBI. A significant increase in CPP was observed in the estrogen group 4 and 24 h post-TBI, while this increase was found in the HC and E2 + LC groups 24 h post-TBI.

Conclusions: A low dose of candesartan did not exert a protective effect on TBI outcomes, but such an effect did appear after combination with estrogen. This finding suggests that interaction between low-dose candesartan and estrogen improves TBI-induced consequences.

Contribution of serum lipids as effect modifiers to a relationship between mean arterial pressure and coronary heart disease in Chinese rural population: the Henan Rural Cohort Study

OBJECTIVES

The aim of this study was to evaluate the relationship between mean arterial pressure (MAP) and coronary heart disease (CHD) in Chinese rural population. In addition, we hypothesised that this relationship might be mediated by some degree of serum lipids.

DESIGN

This is a cross-sectional study.

SETTING

The participants were from the Henan Rural Cohort Study, initiated in five rural areas (Tongxu county of Kaifeng city, Yima county of Sanmenxia city, Suiping county of Zhumadian city, Xinxiang county of Xinxiang city and Yuzhou county of Xuchang city) in Henan Province, China, during July 2015 and September 2017.

PARTICIPANTS

The study included 39 020 subjects aged 18-79 years as current research population.

OUTCOME MEASURES

Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using an electronic sphygmomanometer. MAP was calculated by one-third SBP plus two-thirds DBP. The study used restricted cubic splines and logistic regression models to evaluate the ORs and 95% CIs. Mediation analysis using bootstrap was performed to examine the contribution of serum lipids to MAP-related CHD.

RESULTS

The adjusted OR (95% CI) for the highest MAP quartile with the risk of CHD was 1.45 (1.24 to 1.69) compared with the lowest quartile. Simultaneously, each 1-SD increment in MAP was significantly associated with a 12% increased risk of CHD. A linear dose-response relationship between MAP and CHD was found (p value for non-linear=0.1169) in the fully adjusted model. We further reported that 36.07% of proportion explained risk of CHD was mediated through serum lipids.

CONCLUSIONS

Increased MAP was a significant marker of CHD in Chinese rural population. Meanwhile, the relationship was mediated by some degree of serum lipids, and triglyceride was the strongest mediator.

TRIAL REGISTRATION NUMBER

Henan Rural Cohort study has been registered at Chinese Clinical Trial Register (ChiCTR-OOC-15006699) and the stage it relates to is Post-results.

Can Hypothyroidism Cause Acute Central Serous Chorioretinopathy?

Purpose: To evaluate selected systemic findings, especially thyroid functions, in acute central serous chorioretinopathy (CSC) patients.Materials and Methods: In all, 71 consecutive acute CSC patients who fulfilled the inclusion criteria and 70 age-matched healthy control subjects were included in the study. Systemic findings, including serum levels of thyroid hormones, thyroid stimulating hormone (TSH), mean arterial pressure (MAP), pulse rate, serum lipid levels and optical coherence tomography findings, were compared between the groups. Independent samples t-test was used for statistical analysis.Results: The mean ages of the CSC and control groups were 41.06 ± 6.49 and 40.06 ± 7.08 years old, respectively. Retinal thickness, choroidal thickness, TSH levels, pulse rate and MAP were significantly different between CSC patients and healthy control subjects (range of p values: <0.001-0.042). In the logistic regression analysis, MAP, serum triglyceride concentration and central choroidal thickness were positively associated with CSC (range of p values: <0.001-0.035).Conclusion: Acute CSC patients had significantly higher pulse rates and MAP and significantly thicker choroidal thickness than were found in healthy subjects. TSH levels were also significantly higher in CSC patients than in controls. Hence, hypothyroidism might be associated with CSC.

The influence of gradually increasing the concentration of desflurane on cerebral perfusion pressure in rabbit

BACKGROUND

In nearly all cases of general anaesthesia with a volatile agent, the anaesthetic concentration has to be increased. Since the anaesthetic affects both the factors determining intracranial homeostasis and the systemic circulation, it is crucial that cerebral perfusion pressure (CPP) is protected. The aim of the present study was to assess the influence of gradually increased concentrations of desflurane on the cerebral and systemic circulations based on CPP, mean arterial pressure (MAP), intracranial pressure (ICP) and their correlations.

METHODS

The study was carried out on 25 rabbits of the same gender (male) randomly assigned to two groups: control (n = 10) and group I (n = 15). Over three 15-minute periods, the animals were exposed to increase concentrations of desflurane so as to achieve 1/3, 2/3 and 1 MAC Minimal Alveolar Concentration (3, 6, 9 vol%) of the effective end-tidal concentration of desflurane (Et) at the end of each period, respectively.

RESULTS

Intragroup analysis of CPP changes demonstrated decreases in its successive values from minute 18, compared with baseline values. The mean values of ICP did not differ throughout the experiment. From minute 19 on, all successive values of MAP decreased compared with baseline values. A weak correlation (r = -0.2179) was found between ICP and CPP and a strong correlation between MAP and CPP (r = 0.98829). Moreover, there was a strong correlation between Etdesflurane vs. CPP (r = -0.8769) and MAP (r = -0.8224) and a weak correlation versus ICP (r = 0.15755).

CONCLUSIONS

A decrease in CPP induced by desflurane was associated with a decrease in MAP but not an increase in ICP. The depressive effect of desflurane on the cerebral and systemic circulations is a consequence of its effector site concentration.

Incidence of intraoperative hypotension in acute traumatic spinal cord injury and associated factors

OBJECTIVE

The importance of maintaining mean arterial pressure (MAP) > 85 mm Hg for patients with acute spinal cord injury (SCI) is well documented, because systemic hypotension greatly increases the risk of secondary SCI. Current literature focuses on the ICU setting; however, there is a paucity of data describing the changes in MAP in the operating room (OR). In the present study, the authors investigated the incidence of intraoperative hypotension for patients with acute traumatic SCI as well as any associated factors that may have impacted these findings.

METHODS

This retrospective study was performed at a level 1 trauma center from 2015 to 2016. All patients with American Spinal Injury Association (ASIA) score A-D acute traumatic SCIs from C1 to L1 were identified. Those included underwent spinal instrumentation and/or laminectomy decompression. Associated factors investigated include the following: age, body mass index, trauma mechanism of injury, Injury Severity Score, level of SCI, ASIA score, hospital day of surgery, total OR time, need for laminectomy decompression, use of spinal fixation, surgical positioning, blood loss, use of blood products, length of hospital stay, length of ICU stay, and discharge disposition. Intraoperative minute-by-minute MAP recordings were used to determine time spent in various MAP ranges.

RESULTS

Thirty-two patients underwent a total of 33 operations. Relative to the total OR time, patients spent an average of 51.9% of their cumulative time with an MAP < 85 mm Hg. Furthermore, 100% of the study population recorded at least one MAP measurement < 85 mm Hg. These hypotensive episodes lasted a mean of 103 cumulative minutes per operative case. Analysis of associated factors demonstrated that fall mechanisms of injury led to a statistically significant increase in intraoperative hypotension compared to motor vehicle collisions/motorcycle collisions (p = 0.033). There were no significant differences in MAP recordings when analyzed according to all other associated factors studied.

CONCLUSIONS

This is the first study reporting the incidence of intraoperative hypotension for patients with acute traumatic SCIs, and the results demonstrated higher proportions of relative hypotension than previously reported in the ICU setting. Furthermore, the authors identified that every patient experienced at least one MAP below the target value, which was much greater than the initial hypothesis of 50%. Given the findings of this study, adherence to the MAP protocol intraoperatively needs to be improved to minimize the risk of secondary SCI and associated deleterious neurological outcomes.

Therapeutic hypothermia promotes cerebral blood flow recovery and brain homeostasis after resuscitation from cardiac arrest in a rat model

Laboratory and clinical studies have demonstrated that therapeutic hypothermia (TH), when applied as soon as possible after resuscitation from cardiac arrest (CA), results in better neurological outcome. This study tested the hypothesis that TH would promote cerebral blood flow (CBF) restoration and its maintenance after return of spontaneous circulation (ROSC) from CA. Twelve Wistar rats resuscitated from 7-min asphyxial CA were randomized into two groups: hypothermia group (7 H, n = 6), treated with mild TH (33-34℃) immediately after ROSC and normothermia group (7 N, n = 6,37.0 ± 0.5℃). Multiple parameters including mean arterial pressure, CBF, electroencephalogram (EEG) were recorded. The neurological outcomes were evaluated using electrophysiological (information quantity, IQ, of EEG) methods and a comprehensive behavior examination (neurological deficit score, NDS). TH consistently promoted better CBF restoration approaching the baseline levels in the 7 H group as compared with the 7 N group. CBF during the first 5-30 min post ROSC of the two groups was 7 H:90.5% ± 3.4% versus 7 N:76.7% ± 3.5% (P < 0.01). Subjects in the 7 H group showed significantly better IQ scores after ROSC and better NDS scores at 4 and 24 h. Early application of TH facilitates restoration of CBF back to baseline levels after CA, which in turn results in the restoration of brain electrical activity and improved neurological outcome.

Nocturnal Mean Arterial Pressure Rising Is Associated With Mortality in the Intensive Care Unit: A Retrospective Cohort Study

Background

Disrupted circadian rhythm of blood pressure is commonly observed in patients in the intensive care unit (ICU). This study assessed the association of nocturnal mean arterial pressure rising (NMAPR) with short‐ and long‐term mortality in critically ill adult patients.

Methods and Results

Adult patients with a complete record of mean arterial pressure monitoring during the first 24 hours of ICU stay in the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC‐II) database were included in this retrospective cohort study. All patients were divided into the non‐NMAPR group (≤1) or the NMAPR group (>1), according to the value of mean nighttime divided by daytime mean arterial pressure. The associations of NMAPR with ICU, hospital, 28‐day, and 1‐year mortality were assessed using multivariable logistic regression or a Cox proportional hazards model. Interaction and subgroup analyses were performed for those patients who had a first Sequential Organ Failure Assessment (SOFA) score of ≥8 or <8. The overall cohort comprised 5185 patients. The patients with NMAPR (n=1865) had higher ICU, hospital, 28‐day, and 1‐year mortality than the non‐NMAPR group (n=3320). After adjusting for covariates, the analysis showed that NMAPR was significantly associated with mortality in the ICU (odds ratio: 1.34; 95% CI, 1.10–1.65), in the hospital (odds ratio: 1.35; 95% CI, 1.12–1.63), at 28 days (hazard ratio: 1.27; 95% CI, 1.10–1.48), and at 1 year (hazard ratio: 1.24; 95% CI, 1.10–1.40). All results of the interaction analysis had no statistical significance, and similar results persisted in the patients with different SOFA scores.

Conclusions

NMAPR may aid in the early identification of critically ill patients at high risk of ICU, hospital, 28‐day, or 1‐year mortality.