Role of calcitonin gene-related peptide in cerebral vasospasm, and as a therapeutic approach to subarachnoid hemorrhage

Calcitonin gene-related peptide (CGRP) is one of the most potent microvascular vasodilators identified to date. Vascular relaxation and vasodilation is mediated via activation of the CGRP receptor. This atypical receptor is made up of a G-protein-coupled receptor called calcitonin receptor-like receptor (CLR), a single transmembrane protein called receptor activity-modifying protein (RAMP), and an additional protein that is required for Gas coupling, known as receptor component protein (RCP). Several mechanisms involved in CGRP mediated relaxation have been identified. These include nitric oxide (NO)-dependent endothelium-dependent mechanisms or cAMP-mediated endothelium-independent pathways; the latter being more common. Subarachnoid haemorrhage (SAH) is associated with cerebral vasoconstriction that occurs several days after the haemorrhage and is often fatal. The vasospasm occurs in 30–40% of patients and is the major cause of death from this condition. The vasoconstriction is associated with a decrease in CGRP levels in nerves and an increase in CGRP levels in draining blood, suggesting that CGRP is released from nerves to oppose the vasoconstriction. This evidence has led to the concept that exogenous CGRP may be beneficial in a condition that has proven hard to treat. The present article reviews: a) the pathophysiology of delayed ischaemic neurologic deficit after SAH b) the basics of the CGRP receptor structure, signal transduction and vasodilatation mechanisms and c) the studies that have been conducted so far using CGRP in both animals and humans with SAH

The need for the implementation of an Ecosystem Services assessment in Greece: drafting the national agenda

This paper presents the establishment and the first outcomes of the Hellenic Ecosystem Services Partnership (HESP), a scientific-technical committee aiming at the guidance and coordination of the Ecosystem Services (ES) assessment in Greece. HESP consists of experts from different disciplines (ecology, marine biology, socio-ecological system science) and aims to: i) coordinate ES assessment efforts under a shared framework; ii) promote the ES approach in Greece; iii) support the European implementation of ES at the national level (Mapping and Assessment of Ecosystem and their Services initiative), and iv) fulfill priority actions regarding the ES implementation and the obligations derived from the National Biodiversity Strategy. In this paper, we present the first drafting of the National Agenda including short- and long-term objectives towards the national implementation of MAES, we outline the HESP Action Plan to 2020, as well as the timeline of the basic steps to be taken, to achieve decision making on the basis of ES maintenance and enhancement. It will also serve as a call for action to encourage more ES assessments at the national level, but also as a primer for the inclusion of protected areas and other areas of special importance for ES assessments at the EU level

A multidisciplinary critical review of ecosystem services studies in Greece: approaches, shortcomings and the pathway to implementation

During the last two decades, ecosystem services (ES) research is used to inform the various steps of decision- and policy- making process, regarding environmental management, spatial planning and natural capital accounting. In the EU, this vast and rapid publication boom was triggered by the enactment of Action 5 of the EU Biodiversity Strategy to 2020, urging Member States to implement Mapping and Assessment of Ecosystem and their Services (MAES); few countries pioneered, while others are still lagging behind. In Greece, the implementation of MAES started in 2014 and since then an impressive progress has been made, with Greece now being among the countries with the most rapid progress. However, there are still major knowledge and data gaps on ecosystem services in Greece; know-how on specific methods, tools and practices is still to be developed. This poses obstacles in integrative efforts to identify and/or interpret the various co-variates affecting ecosystems and their services in space and time and hinders the incorporation of the ES generated information into the decision-making process. Making the first steps towards overcoming these hurdles, the present study aims to (i) synthesize the ecosystem services literature relevant to the ES implementation in Greece, (ii) validate and classify each literature source to the relevant ecosystem services categories, (iii) identify shortcomings in terms of ES assessed and data available, and (iv) critically review the variety of approaches to ES assessments that are followed. The outcomes of this study will facilitate the efficient implementation of ecosystem services assessments in Greece

Tooth Aspiration in a Patient with Traumatic Brain Injury

Tooth aspiration is a rare issue in the course of patients with trauma and may remain undiagnosed for a long period, resulting in delayed complications, such as atelectasis and recurrent infections. Flexible bronchoscopy is considered the preferred primary procedure for the management of airway foreign bodies in adults. However, it may cause intracranial hypertension in trauma patients with concomitant head injuries. We herein report a case of a patient with traumatic brain injury who underwent tooth aspiration using flexible bronchoscopy, with continuous monitoring of intracranial pressure (ICP). The importance of a thorough review of radiographs and chest computed tomography for foreign body aspiration in trauma patients was highlighted, particularly in a maxillofacial trauma, as tooth aspiration may remain undiagnosed for extended periods. Moreover, the difficulty in maintaining the ICP within normal limits during bronchoscopy in patients with traumatic brain injury was reinstated, and the need for continuous monitoring of the cerebral hemodynamics and harmonization was emphasized, with recommendations for bronchoscopy via an endotracheal tube

Weaning failure of cardiovascular origin: how to suspect, detect and treat—a review of the literature

Abstract Among the multiple causes of weaning failure from mechanical ventilation, cardiovascular dysfunction is increasingly recognized as a quite frequent cause that can be treated successfully. In this review, we summarize the contemporary evidence of the most important clinical and diagnostic aspects of weaning failure of cardiovascular origin with special focus on treatment. Pathophysiological mechanisms are complex and mainly include increase in right and left ventricular preload and afterload and potentially induce myocardial ischemia. Patients at risk include those with preexisting cardiopulmonary disease either known or suspected. Clinically, cardiovascular etiology as a predominant cause or a contributor to weaning failure, though critical for early diagnosis and intervention, may be difficult to be recognized and distinguished from noncardiac causes suggesting the need of high suspicion. A cardiovascular diagnostic workup including bedside echocardiography, lung ultrasound, electrocardiogram and biomarkers of cardiovascular dysfunction or other adjunct techniques and, in selected cases, right heart catheterization and/or coronary angiography, should be obtained to confirm the diagnosis. Official clinical practice guidelines that address treatment of a confirmed weaning-induced cardiovascular dysfunction do not exist. As the etiologies of weaning-induced cardiovascular dysfunction are diverse, principles of management depend on the individual pathophysiological mechanisms, including preload optimization by fluid removal, guided by B-type natriuretic peptide measurement, nitrates administration in excessive afterload and/or myocardial ischemia, contractility improvement in severe systolic dysfunction as well as other rational treatment in specific indications in order to lead to successful weaning from mechanical ventilation

Fewer Intubations but Higher Mortality Among Intubated Coronavirus Disease 2019 Patients During the Second Than the First Wave.

Since changes in pharmacological treatments for severely ill patients with coronavirus disease 2019 have been incorporated into clinical practice, both by their use (corticosteroids and remdesivir) and by stopping them (e.g., hydroxychloroquine), we sought to compare the rate of intubation and mortality of intubated patients in our ICUs between the first and second waves of the pandemic. DESIGN: Single-center, observational. SETTING: Four coronavirus disease 2019 designated ICUs at an urban Greek teaching hospital. PATIENTS: All adult patients with coronavirus disease 2019 consecutively admitted to ICU during the first (n = 50) and second (n = 212) waves of the pandemic. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The percentage of intubated ICU patients dropped from 82% during the first wave to 66% during the second wave (p = 0.042). However, the absolute number of intubated ICU patients was lower during the first than the second wave (41 vs 140 patients). ICU or hospital mortality of intubated patients increased from 39% during the first wave to 60% during the second wave (p = 0.028). The binary logistic regression for hospital mortality as the dependent variable in intubated patients and covariates the age, Acute Physiology and Chronic Health Evaluation II score, cardiovascular comorbidity, lactate, positive end-expiratory pressure, Sequential Organ Failure Assessment score, and wave, distinguished only Acute Physiology and Chronic Health Evaluation II (odds ratio, 1.40 with 95% CI, 1.14-1.72; p = 0.001) as the sole independent predictor of hospital mortality. CONCLUSIONS: Pharmacological adaptations and other measures may have led to fewer intubations over time. However, these changes do not seem to be translated into improved outcomes of intubated patients. Perhaps the same change in the use of drugs and protocols that could cause fewer intubations of ICU patients might be a reason of increased mortality in those patients who are eventually intubated. Furthermore, the relative staff inexperience and overall increase in patients’ comorbidities during the second wave could have contributed to increased Acute Physiology and Chronic Health Evaluation II score and mortality of intubated patients

Systemic sclerosis associated with generalized vasculitis and hypopituitarism

Systemic sclerosis (SSc) is a progressively evolving multisystemic disorder of unknown etiology. Beyond skin, several other organs can also be affected with a severity of involvement that is often heterogeneous. We describe a 53-year-old female patient who was admitted urgently to the hospital almost collapsed, because of numerous bleeding deep skin ulcers, located all over the body. Clinical findings and autoantibody screening were typical of SSc. Moreover, both histopathology and immunofluorescence findings were compatible with scleroderma and vasculitis as well. In addition, pituitary hormone investigation revealed severely damaged function of the gland. We assume that severe skin ulceration and serious hypopituitarism were both implications of underlying SSc-associated vasculitis. To the best of our knowledge, these peculiar clinical manifestations have not been described in the international literature to date

The effect of high-flow oxygen via tracheostomy on respiratory pattern and diaphragmatic function in patients with prolonged mechanical ventilation: A randomized, physiological, crossover study

Background: Compared to conventional oxygen devices, high-flow oxygen treatment (HFOT) through the nasal cannulae has demonstrated clinical benefits. Limited data exist on whether such effects are also present in HFOT through tracheostomy. Hence, we aimed to examine the short-term effects of HFOT through tracheostomy on diaphragmatic function and respiratory parameters in tracheostomized patients on prolonged mechanical ventilation. Methods: A randomized, crossover, physiological study was conducted in our ICU between December 2020 and April 2021, in patients with tracheostomy and prolonged mechanical ventilation. The patients underwent a 30-min spontaneous breathing trial (SBT) and received oxygen either via T-piece or by HFOT through tracheostomy, followed by a washout period of 15-min breathing through the T-piece and receipt of 30-min oxygen with the other modality in a randomized crossover manner. At the start and end of each session, blood gasses, breathing frequency (f), and tidal volume (VT) via a Wright's spirometer were measured, along with diaphragm ultrasonography including diaphragm excursion and diaphragmatic thickening fraction, which expressed the inspiratory muscle effort. Results: Eleven patients were enrolled in whom 19 sessions were uneventfully completed; eight patients were studied twice on two different days with alternate sessions; and three patients were studied once. Patients were randomly assigned to start the SBT with a T-piece (n=10 sessions) or with HFOT (n=9 sessions). With HFOT, VT and minute ventilation (VE) significantly increased during SBT (from [465±119] mL to [549±134] mL, P <0.001 and from [12.4±4.3] L/min to [13.1±4.2] L/min, P <0.05, respectively), but they did not change significantly during SBT with T-piece (from [495±132] mL to [461±123] mL and from [12.8±4.4] mL to [12.0±4.4] mL, respectively); f/VT decreased during HFOT (from [64±31] breaths/(min∙L) to [49±24] breaths/(min∙L), P <0.001), but it did not change significantly during SBT with T-piece (from [59±28] breaths/(min∙L) to [64±33] breaths/(min∙L)); partial pressure of arterial oxygen increased during HFOT (from [99±39] mmHg to [132±48] mmHg, P <0.001), but it decreased during SBT with T-piece (from [124±50] mmHg to [83±22] mmHg, P <0.01). In addition, with HFOT, diaphragmatic excursion increased (from [12.9±3.3] mm to [15.7±4.4] mm, P <0.001), but it did not change significantly during SBT with T-piece (from [13.4±3.3] mm to [13.6±3.3] mm). The diaphragmatic thickening fraction did not change during SBT either with T-piece or with HFOT. Conclusion: In patients with prolonged mechanical ventilation, HFOT through tracheostomy compared with T-piece improves ventilation, pattern of breathing, and oxygenation without increasing the inspiratory muscle effort. Trial Registration: Clinicaltrials.gov ldentifer: NCT04758910