Non-invasive optical measurement of cerebral critical closing pressure in pediatric hydrocephalus

Hydrocephalus is a common disorder of cerebral spinal fluid (CSF) physiology that results in elevated intracranial pressure (ICP) and progressive expansion of cerebral ventricles.1 It affects 1-2 of every 1000 live births, making it the most common disease treated by pediatric neurosurgeons in the US.1 In roughly half of infants with hydrocephalus, ventricular expansion requires surgical intervention whereby a shunt is placed in the ventricles to divert CSF and relieve elevated ICP. Although timely treatment of elevated ICP is important for brain tissue viability, its implementation is hindered by the lack of tools for non-invasive ICP measurement. This study aims to validate non-invasive intracranial pressure (ICP) assessment with the near-infrared diffuse correlation spectroscopy (DCS) technique in infants with hydrocephalus. DCS employs near-infrared light to measure local, microvascular cerebral blood flow (CBF) continuously at the bedside. In addition to CBF, a novel approach for measurement of cerebral critical closing pressure (CrCP) based on DCS measurements of pulsatile CBF in arterioles was recently demonstrated.2-4 CrCP, which depends on ICP, defines the arterial blood pressure at which CBF approaches zero. Intraoperative non-invasive CrCP measurements with DCS on the prefrontal cortex were performed concurrently with invasive ICP measurements in 9 infants with hydrocephalus at the Children’s Hospital of Philadelphia. Invasive ICP was measured during surgical shunt placement. Please click Additional Files below to see the full abstract

Sonographic evaluation of transjugular intrahepatic porto-systemic shunt

The purpose of this article is to review the role of sonography before, during and after transjugular intrahepatic portosystemic shunt placement. A sonographic assessment of the liver and abdomen is recommended before the procedure. We illustrate several important sonographic findings for the echographist, which may alter the procedure approach or even preclude transjugular intrahepatic portosystemic shunt placement. The most challenging step during the procedure is the puncture of the right portal vein. Sonography can be a helpful tool in reducing the number of needle passes, thereby reducing the risk of hemorrhagic complications. Because of its non-invasive and costbenefit nature, sonography is useful for transjugular intrahepatic portosystemic shunt follow-up. A baseline study at 24 to 48 hours is recommended to discover procedure-related complications. Long-term follow-up is important to detect malfunction of the shunt. Doppler ultrasound is very accurate in detecting shunt thrombosis. However, no consensus exists on the optimal sonographic screening protocol for detecting stenosis. We describe three sonographic parameters to detect transjugular intrahepatic portosystemic shunt stenosis with high sensitivity. Finally, additional sonographic parameters and potential pitfalls are provided in order to improve sensitivity

Exploring the Support Needs of Family Caregivers of Patients with Brain Cancer Using the CSNAT: A Comparative Study with Other Cancer Groups

A substantial burden is placed on family caregivers of patients diagnosed with brain cancers. Despite this, the support needs of the caregivers are often under-recognised and not addressed adequately in current routine and patient centred clinical care. The Care Support Needs Assessment Tool (CSNAT) is a validated instrument designed to systematically identify and address caregiver needs. It has been trialled in an Australian palliative care community setting using a stepped wedge cluster design involving 322 family carers of terminally ill patients. The current article reports on a subset from this trial, 29 caregivers of patients with primary brain cancer, and compares their profile and outcomes to those of other cancer groups. Caregiver strain was assessed using the Family Appraisal of Caregiving Questionnaire, caregiver physical and mental wellbeing using SF12 and caregiver workload using a questionnaire on support with activities of daily living (ADL). In comparison to caregivers of patients with all other cancers, the primary brain cancer group had significantly higher levels of caregiver strain, lower levels of mental wellbeing and a higher level of ADL workload. Their physical wellness also deteriorated significantly over time.An action plan approach led to practical solutions for addressing highlighted concerns. Four themes evolved from the family caregivers’ feedback interviews: The extremely challenging caregiver experience with brain cancer; the systematic and practical approach of the CSNAT during rapid changes; connection with health professionals, feeling acknowledged and empowered; and timely advice and assurance of support during the caregiving journey. This preliminary study has demonstrated that the CSNAT provides a practical and useful tool for assessing the support needs of family caregivers of patients with brain cancer and has provided the basis for a larger scale, longitudinal study that allows a more detailed characterisation of the evolving caregiver needs at different stages of the disease

Trends in biomass, density and diversity of North Sea macrofauna

Total biomass and biomass of large taxonomic groups (polychaetes, molluscs, crustaceans, echinoderms) and species diversity of the macrofauna were determined for almost 200 North Sea stations sampled synoptically by seven vessels during Spring 1986 and for 120 additional stations sampled in earlier years by the Marine Laboratory in Aberdeen. There exists a clear and significant decreasing trend in biomass with latitude, both in total biomass and for the different taxonomic groups. Apart from latitude, sediment composition and chlorophyll a content of the sediment also infuence total biomass and biomass of most groups significantly. Biomass increases consistently in finer sediments and sediments with a higher chlorophyll a content. The same trends are found for the results within laboratories. Some interaction exists, indicating weak laboratory and zonal effects. Diversity, as measured by Hill's diversity index N1 = (exp H′) shows a clear and significant trend with latitude. Towards the north of the North Sea diversity increases considerably. The trend is also found for laboratories separately and is everywhere equally strong. Also longitude and depth show an effect on diversity. Sediment variables have no clear influence on diversity. Other diversity measures show the same trend but are more variable than N1,. Total density tends to increase towards the north, but sediment related variables have a larger influence. Mean individual weight becomes considerably smaller towards the northern part of the North Sea

Parallel chemistry acceleration algorithm with ISAT table-size control in the application of gaseous detonation

In order to improve the computational efficiency of a parallel ISAT (in situ adaptive tabulation)-based chemistry acceleration algorithm in the computations of transient, chemically reacting flows, a control strategy is proposed to maintain the sizes of the data tables in the ISAT computations. The table-size control strategy is then combined with a parallel algorithm to simulate two-dimensional gaseous detonation wave propagation. In the computation of 2H2 + O2 detonation, two sets of tests are conducted to identify the size control strategy. In the first set, the maximum total table size (Mtot) summed over all sub-zones is fixed, while the maximum size of the table on each sub-zone (Msin) is varied. In the second set, a fixed Msin is used for all the tables on the sub-zones while Mtot is varied. A maximum speedup ratio of 4.29 is found in the former tests, while 5.52 is found in the latter. Two parameters, σf and p, are proposed to analyze the load balance and synchronization among table operations in the parallel ISAT computations in the above tests. It is found that both load balance and synchronization have clear influences on the speedup ratio. A parameter pM is defined, and a strategy to choose the optimal maximum table sizes (both Mtot and Msin) based on pM is proposed and is verified to be universal in the computations of both 2H2 + O2 detonation and C2H4 + 3O2 detonation. Finally, the parallel acceleration algorithm enhanced with table-size control is shown to be highly accurate for the detonations in both fuels

Spontaneous life-threatening hemobilia during acute liver failure successfully treated with transarterial embolization

A 28-year-old patient admitted with jaundice, vomiting and deteriorating coagulopathy was diagnosed with acute liver failure. After listing for urgent transplantation, he developed Boerhaave’s syndrome and massive hemobilia, two life-threatening complications. Massive hemobilia secondary to a fistula between the right hepatic artery and the right bile duct occurred several days after transjugular biopsy and was controlled with fluid resuscitation, transfusion and arterial embolization. Two days later he was transplanted successfully, and is currently doing well after more than 72 months. Aggressive treatment of potentially reversible complications during acute liver failure whilst awaiting transplantation is mandatory to allow survival of these patients

Failed surgical ligation of the proximal left subclavian artery during hybrid thoracic endovascular aortic repair successfully managed by percutaneous plug or coil occlusion: a report of 3 cases

Open surgical rerouting and proximal ligation of one or more supra-aortic vessels prior to endovascular stent-graft placement has become an alternative to major open thoracic surgery in the treatment of complex thoracic aortic disease. Complications owing to failed surgical ligation of the left subclavian artery are rare. In this report, 3 cases of failed ligation are presented. Diagnosis was made by CT-scan and treatment was performed by transcatheter coil and plug embolization, avoiding redo neck surgery

Impact of Cardiovascular Risk Factors on Carotid Intima-Media Thickness and Degree of Severity: A Cross-Sectional Study

OBJECTIVE: Age, hypertension, dyslipidemia and diabetes are common cardiovascular risk factors (CVRFs) that contribute to the development of atherosclerosis in cardiovascular system including carotid artery disease. However, the impact of these risk factors on the increased carotid intima-media thickness (cIMT) and degree of carotid severity remains to be further clarified. This study aims to evaluate the relationship between CVRFs and degree of carotid severity and cIMT in high-risk subjects. METHODS: Four thousand and three hundred ninety-four subjects with one or more risk factors were retrospectively reviewed in this study. Patients were divided into different groups based on age, the type and quantity of CVRFs. cIMT and degree of carotid artery stenosis were measured and analyzed based on carotid ultrasound imaging with findings compared to the CVRFs to determine the correlation between these variables. RESULTS: Aging was significantly associated with degree of severity (P < 0.05) and cIMT was significantly increased with age (P < 0.05). Individual CVRF analysis shows that hypertension was more related to the degree of severity than dyslipidemia and diabetes with corresponding abnormal cIMT rates being 79.39%, 72.98% and 32.37%, respectively. The prevalence of carotid atherosclerosis were 20.06%, 22.88% and 28.63%, respectively corresponding to patients with zero, one and more than one chronic diseases. The percentage of abnormal cIMT in hypertensive patient group with dyslipidemia is significantly higher than the other groups (P< 0.05). CONCLUSIONS: This study shows a direct correlation between the degree of carotid severity and cIMT and cardiovascular risk factors, especially with age and hypertension. Carotid atherosclerosis is closely related to the number of cardiovascular risk factors