Fluid-structure interaction simulation of tissue degradation and its effects on intra-aneurysm hemodynamics

Tissue degradation plays a crucial role in vascular diseases such as atherosclerosis and aneurysms. Computational modeling of vascular hemodynamics incorporating both arterial wall mechanics and tissue degradation has been a challenging task. In this study, we propose a novel finite element method-based approach to model the microscopic degradation of arterial walls and its interaction with blood flow. The model is applied to study the combined effects of pulsatile flow and tissue degradation on the deformation and intra-aneurysm hemodynamics. Our computational analysis reveals that tissue degradation leads to a weakening of the aneurysmal wall, which manifests itself in a larger deformation and a smaller von Mises stress. Moreover, simulation results for different heart rates, blood pressures and aneurysm geometries indicate consistently that, upon tissue degradation, wall shear stress increases near the flow-impingement region and decreases away from it. These findings are discussed in the context of recent reports regarding the role of both high and low wall shear stress for the progression and rupture of aneurysms.

Cerebral Blood Flow Monitoring in High-Risk Fetal and Neonatal Populations

Cerebrovascular pressure autoregulation promotes stable cerebral blood flow (CBF) across a range of arterial blood pressures. Cerebral autoregulation (CA) is a developmental process that reaches maturity around term gestation and can be monitored prenatally with both Doppler ultrasound and magnetic resonance imaging (MRI) techniques. Postnatally, there are key advantages and limitations to assessing CA with Doppler ultrasound, MRI, and near-infrared spectroscopy. Here we review these CBF monitoring techniques as well as their application to both fetal and neonatal populations at risk of perturbations in CBF. Specifically, we discuss CBF monitoring in fetuses with intrauterine growth restriction, anemia, congenital heart disease, neonates born preterm and those with hypoxic-ischemic encephalopathy. We conclude the review with insights into the future directions in this field with an emphasis on collaborative science and precision medicine approaches.

Elevated Blood Pressure in Hospitalized Children Predicts True Elevated Blood Pressure Outpatient

OBJECTIVES: To determine if elevated blood pressure (EBP) in hospitalized children accurately predicts EBP outpatient. METHODS: A multicenter retrospective chart review was conducted at a large hospital system in Northeastern United States. Mean blood pressures during hospitalizations were classified as elevated or not elevated, by using the American Academy of Pediatrics (AAP) 2017 parameters. Mean blood pressure was then compared with each patient’s mean blood pressure measured 3 times postdischarge. The data were analyzed to determine if inpatient EBP is an accurate predictor of outpatient EBP. RESULTS: Of 5367 hospitalized children, 656 (12.2%) had EBP inpatient. Inpatient EBP was highly predictive of outpatient EBP, with a positive predictive value of 96% and negative predictive value of 98%. CONCLUSIONS: Diagnosing hospitalized children with EBP, as defined by the AAP 2017 guidelines, accurately predicts true EBP outpatient.

Immediate Hemodynamic Responses to Transcutaneous Electrical Diaphragmatic Stimulation in Critically Ill Elderly Patients

Background. Critically ill patients admitted to intensive care units (ICUs) may develop diaphragmatic dysfunction, especially when artificial airways are used. Positive effects have been observed when using the transcutaneous electrical diaphragmatic stimulation (TEDS) technique in different clinical conditions. However, no study has evaluated the safety of TEDS in patients admitted to ICUs. This study is aimed at evaluating the influence of TEDS on the hemodynamic and vital parameters of critically ill elderly patients under invasive mechanical ventilation (IMV). Methods. Forty-seven patients aged >60 years under IMV were evaluated for hemodynamic variables before and after TEDS. The procedure lasted 30 minutes and was performed once. Results. The sample consisted of 33 men and 14 women with a mean age of 69.9 ± 7.64 years. The mean systolic blood pressures pre-TEDS and post-TEDS were 126.6 ± 23.7 and 122.9 ± 25.9 , respectively ( p = 0.467 ). The mean diastolic blood pressures pre-TEDS and post-TEDS were 71.1 ± 12.2 and 67.7 ± 14.2 , respectively ( p = 0.223 ). No significant differences in the mean arterial pressure or heart rate were found between the pre-TEDS and post-TEDS time points ( p = 0.335 and p = 0.846 , respectively). Conclusion. Our findings suggest that TEDS does not have clinically relevant impacts on hemodynamic or vital parameters in critically ill elderly patients. These findings point to the possible safety of TEDS application in this population.

Study of the effect of high blood pressure on the kidney in Children with COVID-19 (Preprint)

UNSTRUCTURED Hypertension is considered as a comorbid condition for the novel coronavirus 2019 (COVID-19). However, there are no reports of “Hypertension crisis” as a presentation or comorbidity of the COVID-19 infection in pediatric patients. In this retrospective observational study, we collected data from total six pediatric patients, diagnosed with confirmed COVID-19 positive who had presented with acute severe hypertension. The mean age of patients was 4.2 years. Four cases were with newly diagnosed nephrotic syndrome and two with chronic kidney disease who were on regular dialysis with no edema or sign of fluid overload, were enrolled. The lowest and highest systolic blood pressures at the time of admission were 160 mmHg and 200 mmHg, respectively. The diastolic blood pressures were between 100-155 mmHg. All patients treated with Labetalol infusion titrated to maximum dosage and continued for at least one week. Our reported children had resistant hypertension and their blood pressure had been controlled with four or five antihypertensive medications. It is crucial to consider the diagnosis of COVID-19 in a patient presenting with a hypertension crisis, even in the absence of classic signs of the virus. Thus from our study we strongly recommend the medical practitioners to consider the probability of COVID-19 infection in cases presenting to the hospital with acute severe hypertension.

Arterial hypertension in women: Menopause as a risk window

Objectives Cardiovascular diseases (CVD) exert a heavy toll on health of women, mainly due to hypertension said to cluster around the period of transition to menopause. This makes this period a good window to target for prevention and control. We therefore sought to determine if this period really heralds arterial hypertension and CVD in women in our environment. Study design We secondarily analysed our population data on CVD risk factors in free living rural residents. Main outcome variables The data considered were blood pressure, anthropometric and biochemical variables in women stratified based on menstruation status. Results There were 488 females, with 218 still menstruating. They were younger ( p = .000), had lower systolic and diastolic blood pressures ( p = .000), lower anthropometric indices attaining significance only with waist circumference ( p = .001) and lower total cholesterol ( p = .001). Controlling for age, statistically significant differences remained for systolic and diastolic blood pressures, body mass index, waist and hip circumferences, and total cholesterol. Conclusion The menopause transition comes with a worse CVD profile. Blood pressure rises and so are the anthropometric variables and some biochemical parameters that fuel CVD. This could be ascribed to age which is higher with those post-menopausal. Controlling for age in this cohort still showed that transiting from pre- to post-menopause still came with CVD burden. Clinicians should take the opportunity presented by menopause transition to screen for CVD risk factors and initiate either preventive or control measures to mitigate morbi-mortality consequences.

Post-dynamic Resistance Exercise Hypotension: Exploring Individual Responses and Predictors

Background: Post-dynamic resistance exercise hypotension (PREH) has been largely demonstrated. However, little is known regarding the interindividual variation of PREH magnitude and its predictors (i.e. factors of influence).Aims: To assess the interindividual variation of PREH and its predictors related to the characteristics of the individuals and the exercise protocol.Methods: This study retrospectively analysed data from 131 subjects included in seven controlled trials about PREH (including at least one dynamic resistance exercise and one control session) conducted by two research laboratories. The interindividual variation was assessed by the standard deviation of the individual responses (SDIR), and linear regression analyses were conducted to explore the predictors.Results: PREH showed moderate interindividual variation for systolic (SBP, SDIR=4.4mmHg; 0.35 standardised units) and diastolic blood pressures (DBP, SDIR=3.6mmHg; 0.32 standardised units). For systolic PREH, multivariate regression analysis (R2=0.069) revealed higher baseline SBP (B=−0.157, p=0.008) and higher number of sets (B=−3.910, p=0.041) as significant predictors. For diastolic PREH, multivariate regression analysis (R2=0.174) revealed higher baseline DBP (B=−0.191, p=0.001) and higher exercise volume (i.e. number of exercises *sets per exercise *repetitions per sets >150; B=−4.212, p=0.001) as significant predictors.Conclusion: PREH has a considerable interindividual variation. Greater PREH magnitude is observed in individuals with higher baseline blood pressure and after exercise protocols that comprehend higher number of sets and exercise volume.

Association between pulse pressure and progression of chronic kidney disease

The aim of this study was to investigate the association between pulse pressure (PP) and chronic kidney disease (CKD) progression among the general population in Japan. We conducted a population-based cohort study of the residents of Iki Island, Nagasaki, Japan, from 2008 to 2018. We identified 1042 participants who had CKD (estimated glomerular filtration rate(eGFR) < 60 mL/min/1.73 m2 or the presence of proteinuria) at baseline. Cox’s proportional hazard model was used to evaluate the association between PP and progression of CKD. During a 4.66-year mean follow-up, there were 241 cases of CKD progression (incident rate: 49.8 per 1000 person-years). A significant increase existed in CKD progression per 10 mmHg of PP elevation, even when adjusted for confounding factors [adjusted hazard ratio 1.17 (1.06–1.29) p < 0.001]. Similar results were obtained even after dividing PP into quartiles [Q2: 1.14 (0.74–1.76), Q3: 1.35 (0.88–2.06), Q4: 1.87 (1.23–2.83) p = 0.003 for trend]. This trend did not change significantly irrespective of baseline systolic or diastolic blood pressures. PP remained a potential predictive marker, especially for eGFR decline. In conclusion, we found a significant association between PP and CKD progression. PP might be a potential predictive marker for CKD progression.

Haemodynamic effects of a prehospital emergency anaesthesia protocol consisting of fentanyl, ketamine and rocuronium in patients with trauma: a retrospective analysis of data from a Helicopter Emergency Medical Service

ObjectivesPrehospital rapid sequence induction (RSI) of anaesthesia is an intervention with significant associated risk. In this study, we aimed to investigate the haemodynamic response over time of a prehospital RSI protocol of fentanyl, ketamine and rocuronium in a heterogeneous population of trauma patients.Design, setting and participantWe performed a retrospective study of all trauma patients who received a prehospital RSI for trauma by a physician staffed Helicopter Emergency Medical Service in the UK between 1 June 2018 and 1 February 2020.Primary outcome measurePrimary outcome was defined as the incidence of clinically relevant hypotensive (systolic blood pressure (SBP) or mean arterial pressure (MAP) >20% below baseline, with an absolute SBP <90 mm Hg or MAP <65 mm Hg) or hypertensive (SBP or MAP >20% above baseline) episodes in the first 10 minutes post-RSI.ResultsIn total, 322 patients were included. 204 patients (63%) received a full-dose induction of 3 μg/kg fentanyl, 2 mg/kg ketamine and 1 mg/kg rocuronium, whereas 128 patients (37%) received a reduced-dose induction. Blood pressures decreased on average 12 mm Hg (95% CI 7 to 16) in the full-dose group and 6 mm Hg (95% CI 1 to 11) in the reduced-dose group, p=0.10). A hypotensive episode (mean SBP drop 53 mm Hg) was noted in 29 patients: 17 (8.3%) receiving a full dose and 12 (10.2%) receiving a reduced-dose induction, p=0.69. The blood pressure nadir was recorded on average 6–8 min after RSI. A hypertensive episode was present in 22 patients (6.8%). The highest blood pressures were recorded in the first 3 min after RSI.ConclusionPrehospital induction of anaesthesia for trauma with fentanyl, ketamine and rocuronium is not related to a significant change in haemodynamics in most patients. However, a (delayed) hypotensive response with a significant drop in SBP should be anticipated in a minority of patients irrespective of the dose regimen chosen.

Outcome and Incidence of Acute Kidney Injury among Hospitalized Children

Background and purpose: Data on the epidemiology of acute kidney injury (ARI) in Asia come primarily from studies conducted in large tertiary hospitals with nephrology departments. Little is known about what happens in primary care settings without nephrology, especially in the paediatric population. The aim of this study is to describe the epidemiology, outcome and risk factors of ARF in children admitted in pediatric department. Place and Duration: In the Pediatric Medicine and Nephrology department of Abbasi Shaheed Hospital for one-year duration from August 2020 to August 2021. Methods: We prospectively examined children aged 2 to 14 whose guardians gave the consent for the study and were admitted in the Pediatric ward. We identified children with risk factors for AKI on admission and then tested them for AKI using the 2012 Creatinine-based Modified General Kidney Disease Improvement (KDIGO) criteria to improve overall outcomes. Participants with AKI were followed up to discharge. The subject of interest was the need and access to dialysis and renal recovery on discharge from the hospital. Results: A total of 74.3% (n = 116) out of the 156 patients admitted during the study period were at risk of ARF. Of the 156 registered participants, 51.9% (n = 81) were males with a mean age of 5 years. Although comorbid conditions were rare, sickle cell anaemia and malnutrition were the most common. Most of the children were hypotensive (n = 89; 57.1%), with mean systolic and diastolic blood pressures of 81 mmHg and 42 mmHg, respectively. The mean urine output was 0.79 ml / kg / hr. Thirteen patients (8.33%) had urine dipstick anomalies. Anaemia was common (n = 72, 46.2%) and 32 (20.5%) had severe anaemia. Leucocytosis was detected in 26.3% of patients, and a platelet count below 100,000 / mm3 in 24 (15.4%) patients. In total, 21 of 156 participants had AKI for an incidence of 13.5%. The only patient with an indication for dialysis (uremic encephalopathy and anuria> 24 hours) died without dialysis due to a delay in transfer to a dialysis centre (due to lack of resources). Of the 20 survivors in the AKI group, 15 (71.4%) had complete improvement in kidney function The median hospitalization time was significantly longer in participants with stage 3 AKI. Conclusions: ARF risk factors are very common in children admitted in the hospitals. At least one in 10 children presenting with AKI risk factors will have AKI. AKI is largely caused by community-acquired diseases that can be prevented, such as diarrheal diseases and malaria. Efforts should be made to educate about risk assessment, prevention, early diagnosis and treatment of AKI in children. Keywords: AKI; epidemiology; risk factors and outcome.