Intracranial Pressure and Cerebral Hemodynamics in Infants Before and After Glenn Procedure.

OBJECTIVES: This prospective cohort study aimed to investigate changes in intracranial pressure (ICP) and cerebral hemodynamics in infants with congenital heart disease undergoing the Glenn procedure, focusing on the relationship between superior vena cava pressure and estimated ICP. DESIGN: A single-center prospective cohort study. SETTING: The study was conducted in a cardiac center over 4 years (2019-2022). PATIENTS: Twenty-seven infants with congenital heart disease scheduled for the Glenn procedure were included in the study, and detailed patient demographics and primary diagnoses were recorded. INTERVENTIONS: Transcranial Doppler (TCD) ultrasound examinations were performed at three time points: baseline (preoperatively), postoperative while ventilated (within 24-48 hr), and at discharge. TCD parameters, blood pressure, and pulmonary artery pressure were measured. MEASUREMENTS AND MAIN RESULTS: TCD parameters included systolic flow velocity, diastolic flow velocity (dFV), mean flow velocity (mFV), pulsatility index (PI), and resistance index. Estimated ICP and cerebral perfusion pressure (CPP) were calculated using established formulas. There was a significant postoperative increase in estimated ICP from 11 mm Hg (interquartile range [IQR], 10-16 mm Hg) to 15 mm Hg (IQR, 12-21 mm Hg) postoperatively (p = 0.002) with a trend toward higher CPP from 22 mm Hg (IQR, 14-30 mm Hg) to 28 mm Hg (IQR, 22-38 mm Hg) postoperatively (p = 0.1). TCD indices reflected alterations in cerebral hemodynamics, including decreased dFV and mFV and increased PI. Intracranial hemodynamics while on positive airway pressure and after extubation were similar. CONCLUSIONS: Glenn procedure substantially increases estimated ICP while showing a trend toward higher CPP. These findings underscore the intricate interaction between venous pressure and cerebral hemodynamics in infants undergoing the Glenn procedure. They also highlight the remarkable complexity of cerebrovascular autoregulation in maintaining stable brain perfusion under these circumstances.

Does interatrial communication affect post-operative course of children undergoing tetralogy of Fallot repair? Single centre retrospective cohort study: propensity score matching.

INTRODUCTION: During tetralogy of Fallot repair, leaving or even create an interatrial communication may facilitate post-operative course particularly with right ventricle restrictive physiology. The aim of our study is to assess the influence of atrial communication on post-operative course of tetralogy of Fallot repair. METHODS: Retrospectively, we studied all children who had tetralogy of Fallot repair (2003-2018). We divided them into two groups: tetralogy of Fallot repair with interatrial communication (TOFASD) group and tetralogy of Fallot repair with intact atrial septum (TOFIAS) group. We performed propensity match score for specific pre- or intra-operative variables and compared groups for post-operative outcome variables. Secondarily, we looked for right ventricle restrictive physiology incidence and influence of early repair performed before 3 months of age on post-operative course. RESULTS: One hundred and sixty children underwent tetralogy of Fallot repair including (93) cases of TOFIAS (58%) and (67) cases of TOFASD (42%). With propensity matching score, 52 patients from each group were compared. Post-operative course was indifferent in term of positive pressure ventilation time, vasoactive inotropic score, creatinine and lactic acid levels, duration and amount of chest drainage and length of intensive care unit and hospital stay. Right ventricle restrictive physiology occurred in 38% of patients with no effects on outcome. 12/104 patients (12%) with early repair needed longer pressure ventilation time (p = 0.003) and intensive care unit stay (p = 0.02). CONCLUSION: Leaving interatrial communication in tetralogy of Fallot repair did not affect post-operative course. As well, right ventricle restrictive physiology did not affect post-operative course. Infants undergoing early tetralogy of Fallot repair may require longer duration of positive pressure ventilation time and intensive care unit stay.

X-ray tomography analysis reveals the influence of graphene on porous morphology of collagen cryogels.

X-ray micro-tomography based analysis of porous hydrogel has gained a wide attention recently. It provides an advantage in three-dimensional analysis of pore morphometric and interconnection within the hydrogel network. We have fabricated highly elastic graphene crosslinked collagen hydrogel using cryogelation technique. The influence of graphene as a nano-crosslinker on the overall porosity and inter-connections between the pores in collagen cryogels was determined using X-ray micro-tomography. We have evaluated the effect of different concentration of amino-functionalized graphene nano-crosslinker on collagen cryogels porosity, pore volume, interconnectivity density, fractal dimensions and pore wall thickness. This study, reveals that the use of graphene as a nano-crosslinker have improved micro-architecture as compare to collagen cryogels in the absence of graphene for tissue engineering applications.

Use of Synchrotron Phase-Sensitive Imaging for the Investigation of Magnetopriming and Solar UV-Exclusion Impact on Soybean (Glycine max) Leaves.

The combined response of exclusion of solar ultraviolet radiation (UV-A+B and UV-B) and static magnetic field (SMF) pre-treatment of 200 mT for 1 h were studied on soybean (Glycine max) leaves using synchrotron imaging. The seeds of soybean with and without SMF pre-treatment were sown in nursery bags kept in iron meshes where UV-A+B (280-400 nm) and UV-B (280-315 nm) from solar radiation were filtered through a polyester filters. Two controls were planned, one with polythene filter controls (FC)- which allows all the UV (280-400 nm); the other control had no filter used (open control-OC). Midrib regions of the intact third trifoliate leaves were imaged using the phase-contrast imaging technique at BL-4, Indus-2 synchrotron radiation source. The solar UV exclusion results suggest that ambient UV caused a reduction in leaf growth which ultimately reduced the photosynthesis in soybean seedlings, while SMF treatment caused enhancement of leaf growth along with photosynthesis even under the presence of ambient UV-B stress. The width of midrib and second-order veins, length of the second-order veins, leaf vein density, and the density of third-order veins obtained from the quantitative image analysis showed an enhancement in the leaves of plants that emerged from SMF pre-treated seeds as compared to untreated ones grown in open control and filter control conditions (in the presence of ambient UV stress). SMF pre-treated seeds along with UV-A+B and UV-B exclusion also showed significant enhancements in leaf parameters as compared to the UV excluded untreated leaves. Our results suggested that SMF-pretreatment of seeds diminishes the ambient UV-induced adverse effects on soybean.

Magnetopriming effects on arsenic stress-induced morphological and physiological variations in soybean involving synchrotron imaging.

This study investigates the effect of static magnetic field (SMF) pre-treatment in ameliorating arsenic (As) toxicity in soybean plants in relation to growth, photosynthesis and water transport through leaf venation. Soybean (Glycine max variety JS-9560) seeds pre-treated with SMF (200 mT for 1 h) were grown in four levels of arsenate-polluted soil (As(V); 0, 5, 10 and 50 mg kg-1 ) in order to find out the impact of magnetopriming on plant tolerance against As toxicity. Quantitative image analysis of soybean leaf venation showed a narrowing in the width of midrib with increasing As(V) contamination in non-primed seeds. The morphological variations are also supported by the physiological parameters such as reduction in efficiency of photosystem II, plant performance index, stomatal conductance and photosynthetic rate in the presence of As(V) for non-primed seeds. However, remarkable increase was observed in all the measured parameters by SMF pre-treatment at all the concentrations of As(V) used. Even for the highest concentration of As(V) (50 mg kg-1 soil), SMF pre-treatment caused significant enhancement in plant height (40%), area of third trifoliate leaves (40%), along with increase in width of the midrib (17%) and minor vein (13%), contributing to increase in the water uptake, that resulted in higher primary photochemistry of PSII (12%), performance index (50%), stomatal conductance (57%) and photosynthetic rate (33%) as compared to non-primed ones. Consequently, magnetopriming of dry seeds can be effectively used as pretreatment for reduction of As toxicity in soybean plants.

Urinary tract infection in children after cardiac surgery: Incidence, causes, risk factors and outcomes in a single-center study.

Nosocomial urinary tract infection (UTI) increases hospitalization, cost and morbidity. In this cohort study, we aimed to determine the incidence, risk factors, etiology and outcomes of UTIs in post-operative cardiac children. To this end, we studied all post-operative patients admitted to the Pediatric Cardiac Intensive Care Unit (PCICU) in 2012, and we divided the patients into two groups: the UTI (UTI group) and the non-UTI (control group). We compared both groups for multiple peri-operative risk factors. We included 413 children in this study. Of these, 29 (7%) had UTIs after cardiac surgery (UTI group), and 384 (93%) were free from UTIs (control group). All UTI cases were catheter-associated UTIs (CAUTIs). A total of 1578 urinary catheter days were assessed in this study, with a CAUTI density rate of 18 per 1000 catheter days. Multivariate logistic regression analysis demonstrated the following risk factors for CAUTI development: duration of urinary catheter placement (p<0.001), presence of congenital abnormalities of kidney and urinary tract (CAKUT) (p<0.0041) and the presence of certain syndromes (Down, William, and Noonan) (p<0.02). Gram-negative bacteria accounted for 63% of the CAUTI. The main causes of CAUTI were Klebsiella (27%), Candida (24%) and Escherichia coli (21%). Resistant organisms caused 34% of CAUTI. Two patients (7%) died in the UTI group compared with the one patient (0.3%) who died in the control group (p<0.05). Based on these findings, we concluded that an increased duration of the urinary catheter, the presence of CAKUT, and the presence of syndromes comprised the main risk factors for CAUTI. Gram-negative organisms were the main causes for CAUTI, and one-third of them found to be resistant in this single-center study.