Carotid endarterectomy in patients with asymptomatic intracranial aneurysm.

The patient with symptomatic extracranial carotid artery disease who, on angiography, is found to have a coexisting intracranial aneurysm presents a therapeutic dilemma. Relief of the carotid stenosis, with a potential increase in cerebral blood pressure, might increase the risk of aneurysm rupture. Conversely, repair of the aneurysm may be hazardous because of the low flow imposed by the carotid stenosis, particularly in the event of perioperative hypotension. We reviewed 19 patients treated with 20 carotid endarterectomies in the face of concurrent asymptomatic intracranial aneurysm. There were no instances of aneurysm rupture during the operation or the 30 days following operation. The literature reported to date consists of a total of 20 patients with only one incidence of aneurysm rupture in the postoperative period. We conclude that carotid endarterectomy is unlikely to precipitate rupture of an intracranial aneurysm during the operation or postoperative period.     

Relief of nonhemispheric symptoms in low flow states by anterior circulation revascularization: a physiologic approach

Operative intervention remains controversial for patients with transient nonhemispheric symptoms with occlusive disease of both the anterior and posterior cerebral circulations. In addition to the standard evaluation of these patients, we have used stable xenon-enhanced computed tomographic mapping of cerebral blood flow (Xe/CT CBF). This relatively new and potentially widely available CBF methodology, by measuring approximately 30,000 CBF values within each of three CT levels, provides a readily interpretable means of evaluating extremes of hemodynamic compromise within any or all vascular territories. In the past 30 months, Xe/CT CBF studies in 300 patients with occlusive vascular disease have identified nine patients with global low flow and nonhemispheric symptoms (vertigo, lightheadedness, and/or blurred vision). Blood pressures determined by ocular pneumoplethysmography of Gee were markedly abnormal with reduced ocular/brachial ratios. Each patient had a combination of both segmental carotid and vertebrobasilar occlusive disease. Each patient had a flow-augmenting procedure performed on the anterior circulation in an attempt to improve global flow: carotid endarterectomy (two patients), subclavian-external carotid bypass (one patient), and superficial temporal artery-middle cerebral artery bypass (six patients). In each case disabling transient symptoms were relieved. There were no operative deaths, but one stroke occurred, probably as a result of a brief period of postoperative hypotension. Postoperative Xe/CT CBF studies show a long-term improved global CBF in all patients.     

Cerebral revascularization for cerebral ischemia and stroke prevention in patients with atherosclerotic occlusive disease: defining the population that benefits

The decision to perform a revascularization procedure on a patient who may or may not benefit from it must be based on an understanding of the impact of spontaneous or therapeutic vascular occlusion on the physiologic, by which the cerebral circulation compensates for vascular occlusions. This impact is patient specific and requires examination of a number of possible physiologic parameters.     

Noninvasive continuous monitoring of cerebral oxygenation periictally using near-infrared spectroscopy: a preliminary report

PURPOSE: To report on the use of near-infrared spectroscopy (NIRS) to examine the changes in cerebral oxygenation in the periictal period in patients with seizures. METHODS: Cerebral hemoglobin oxygen availability was monitored continuously and noninvasively with NIRS in three patients (one in the pediatric intensive care unit (ICU) and two in epilepsy-monitoring units) in conjunction with continuous EEG monitoring. Ictal events were recorded and compared with the pre-, intra-, and postictal periods for cerebral oxygen availability, as defined by oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (Hb), and the redox state of cytochrome oxidase (cytox). RESULTS: Several important preliminary observations were made by using this technology. First, a preictal increase in cerebral oxygenation began between 1 and 2 h and >10 h before the ictal event. Second, despite adequate perfusion, based on an observed increased HbO2, reduction in cytox indicates a perfusion-metabolism mismatch during seizure activity. Third, continued seizure activity and even isolated ictal events were associated with decreased cerebral oxygen availability. Fourth, differences in cerebral oxygen availability were noted between different types of seizures (e.g., electrographic seizures were accompanied by rapid reductions in HbO2 and cerebral blood volume without reduction of cytox, whereas electroclinical seizures were characterized by marked increases in HbO2 with or without reduction of cytox). CONCLUSIONS: In this preliminary report on the use of NIRS for patients with seizures, we believe that NIRS allows continuous and noninvasive monitoring of changes in cerebral oxygenation periictally, thereby permitting investigations into the pathophysiology of seizures and the exploration of the potential of cerebral oximetry as a tool for seizure localization.     

Maternal behavioural determinants and livestock ownership are associated with animal source food consumption among young children during fasting in rural Ethiopia

Religious fasting often involves abstention from animal source foods (ASFs). Although children are exempt, their diets are influenced by the widespread fasting practices. This study investigated the factors influencing ASF consumption among young children during the Lent fasting period in western Amhara, Ethiopia. We used baseline survey data from households with children 6–23 months of age (n = 2,646). We conducted regression analysis to examine the maternal and household factors associated with ASF consumption and path analysis to examine the direct and indirect effects of maternal knowledge, beliefs, social norms, and livestock ownership on ASF consumption. Only 24% of children consumed any ASF in the previous day—18% dairy products, 5% eggs, and 2% flesh foods. Mothers with high knowledge, beliefs, and social norms about feeding children ASFs during fasting had higher odds (odds ratio: 1.3–1.4) of children who consumed them. Compared with households with no ASFs, those with ASFs available were 4.8 times more likely to have children who consumed them. Most of the association between knowledge, beliefs and social norms, and ASF consumption was explained by pathways operating through ASF availability (approximately 9, 12, and 8 pp higher availability, respectively), which in turn were associated with higher consumption. Cow ownership was directly and indirectly associated with ASF consumption, whereas having chickens was indirectly associated with consumption via the availability pathway. Our findings corroborate the importance of maternal behavioural determinants related to feeding ASFs to children during fasting on ASF consumption via household availability and the positive influence of livestock ownership.     

Validation of a Novel Murine Wound Model of Acinetobacter baumannii Infection

Patients recovering from traumatic injuries or surgery often require weeks to months of hospitalization, increasing the risk for wound and surgical site infections caused by ESKAPE pathogens, which include A. baumannii (the ESKAPE pathogens are Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). As new therapies are being developed to counter A. baumannii infections, animal models are also needed to evaluate potential treatments. Here, we present an excisional, murine wound model in which a diminutive inoculum of a clinically relevant, multidrug-resistant A. baumannii isolate can proliferate, form biofilms, and be effectively treated with antibiotics. The model requires a temporary, cyclophosphamide-induced neutropenia to establish an infection that can persist. A 6-mm-diameter, full-thickness wound was created in the skin overlying the thoracic spine, and after the wound bed was inoculated, it was covered with a dressing for 7 days. Uninoculated control wounds healed within 13 days, whereas infected, placebo-treated wounds remained unclosed beyond 21 days. Treated and untreated wounds were assessed with multiple quantitative and qualitative techniques that included gross pathology, weight loss and recovery, wound closure, bacterial burden, 16S rRNA community profiling, histopathology, peptide nucleic acid-fluorescence in situ hybridization, and scanning electron microscopy assessment of biofilms. The range of differences that we are able to identify with these measures in antibiotic- versus placebo-treated animals provides a clear window within which novel antimicrobial therapies can be assessed. The model can be used to evaluate antimicrobials for their ability to reduce specific pathogen loads in wounded tissues and clear biofilms. Ultimately, the mouse model approach allows for highly powered studies and serves as an initial multifaceted in vivo assessment prior to testing in larger animals.     

A retrospective review on the histopathological pattern of childhood malignant solid tumors in Ethiopia

In low- and middle-income countries (LMICs), malignancies remain underreported due to lack of quality data. This study outlines the histopathological pattern of pediatric solid malignancies in children aged 0–15 years at the largest referral hospital in Ethiopia. A total of 432 solid malignancies were evaluated. The most common malignancies were lymphoma (21.8%), retinoblastoma (19.4%), and Wilms tumor (13.9%). Burkitt lymphoma accounted for 2.1%, despite being the most reported pediatric malignancy in sub-Saharan Africa in published literature. Definitive diagnosis could not be made in 7% of cases, related to the lack of confirmatory testing. The study highlights the need for improvement in diagnostic capabilities in LMICs.