Variation in Structure and Process of Care in Traumatic Brain Injury: Provider Profiles of European Neurotrauma Centers Participating in the CENTER-TBI Study.

INTRODUCTION: The strength of evidence underpinning care and treatment recommendations in traumatic brain injury (TBI) is low. Comparative effectiveness research (CER) has been proposed as a framework to provide evidence for optimal care for TBI patients. The first step in CER is to map the existing variation. The aim of current study is to quantify variation in general structural and process characteristics among centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. METHODS: We designed a set of 11 provider profiling questionnaires with 321 questions about various aspects of TBI care, chosen based on literature and expert opinion. After pilot testing, questionnaires were disseminated to 71 centers from 20 countries participating in the CENTER-TBI study. Reliability of questionnaires was estimated by calculating a concordance rate among 5% duplicate questions. RESULTS: All 71 centers completed the questionnaires. Median concordance rate among duplicate questions was 0.85. The majority of centers were academic hospitals (n = 65, 92%), designated as a level I trauma center (n = 48, 68%) and situated in an urban location (n = 70, 99%). The availability of facilities for neuro-trauma care varied across centers; e.g. 40 (57%) had a dedicated neuro-intensive care unit (ICU), 36 (51%) had an in-hospital rehabilitation unit and the organization of the ICU was closed in 64% (n = 45) of the centers. In addition, we found wide variation in processes of care, such as the ICU admission policy and intracranial pressure monitoring policy among centers. CONCLUSION: Even among high-volume, specialized neurotrauma centers there is substantial variation in structures and processes of TBI care. This variation provides an opportunity to study effectiveness of specific aspects of TBI care and to identify best practices with CER approaches

Variation in neurosurgical management of traumatic brain injury

Background: Neurosurgical management of traumatic brain injury (TBI) is challenging, with only low-quality evidence. We aimed to explore differences in neurosurgical strategies for TBI across Europe. Methods: A survey was sent to 68 centers participating in the Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. The questionnaire contained 21 questions, including the decision when to operate (or not) on traumatic acute subdural hematoma (ASDH) and intracerebral hematoma (ICH), and when to perform a decompressive craniectomy (DC) in raised intracranial pressure (ICP). Results: The survey was completed by 68 centers (100%). On average, 10 neurosurgeons work in each trauma center. In all centers, a neurosurgeon was available within 30 min. Forty percent of responders reported a thickness or volume threshold for evacuation of an ASDH. Most responders (78%) decide on a primary DC in evacuating an ASDH during the operation, when swelling is present. For ICH, 3% would perform an evacuation directly to prevent secondary deterioration and 66% only in case of clinical deterioration. Most respondents (91%) reported to consider a DC for refractory high ICP. The reported cut-off ICP for DC in refractory high ICP, however, differed: 60% uses 25 mmHg, 18% 30 mmHg, and 17% 20 mmHg. Treatment strategies varied substantially between regions, specifically for the threshold for ASDH surgery and DC for refractory raised ICP. Also within center variation was present: 31% reported variation within the hospital for inserting an ICP monitor and 43% for evacuating mass lesions. Conclusion: Despite a homogeneous organization, considerable practice variation exists of neurosurgical strategies for TBI in Europe. These results provide an incentive for comparative effectiveness research to determine elements of effective neurosurgical care

Variation in general supportive and preventive intensive care management of traumatic brain injury: a survey in 66 neurotrauma centers participating in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study

Abstract Background General supportive and preventive measures in the intensive care management of traumatic brain injury (TBI) aim to prevent or limit secondary brain injury and optimize recovery. The aim of this survey was to assess and quantify variation in perceptions on intensive care unit (ICU) management of patients with TBI in European neurotrauma centers. Methods We performed a survey as part of the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. We analyzed 23 questions focused on: 1) circulatory and respiratory management; 2) fever control; 3) use of corticosteroids; 4) nutrition and glucose management; and 5) seizure prophylaxis and treatment. Results The survey was completed predominantly by intensivists (n = 33, 50%) and neurosurgeons (n = 23, 35%) from 66 centers (97% response rate). The most common cerebral perfusion pressure (CPP) target was > 60 mmHg (n = 39, 60%) and/or an individualized target (n = 25, 38%). To support CPP, crystalloid fluid loading (n = 60, 91%) was generally preferred over albumin (n = 15, 23%), and vasopressors (n = 63, 96%) over inotropes (n = 29, 44%). The most commonly reported target of partial pressure of carbon dioxide in arterial blood (PaCO2) was 36–40 mmHg (4.8–5.3 kPa) in case of controlled intracranial pressure (ICP) < 20 mmHg (n = 45, 69%) and PaCO2 target of 30–35 mmHg (4–4.7 kPa) in case of raised ICP (n = 40, 62%). Almost all respondents indicated to generally treat fever (n = 65, 98%) with paracetamol (n = 61, 92%) and/or external cooling (n = 49, 74%). Conventional glucose management (n = 43, 66%) was preferred over tight glycemic control (n = 18, 28%). More than half of the respondents indicated to aim for full caloric replacement within 7 days (n = 43, 66%) using enteral nutrition (n = 60, 92%). Indications for and duration of seizure prophylaxis varied, and levetiracetam was mostly reported as the agent of choice for both seizure prophylaxis (n = 32, 49%) and treatment (n = 40, 61%). Conclusions Practice preferences vary substantially regarding general supportive and preventive measures in TBI patients at ICUs of European neurotrauma centers. These results provide an opportunity for future comparative effectiveness research, since a more evidence-based uniformity in good practices in general ICU management could have a major impact on TBI outcome

Importance of seismic site response and soil–structure interaction in dynamic behaviour of a tall building

A tall public building in Naples (Italy) has recently undergone a seismic vulnerability assessment, following the new Italian code requirements. The building is about 100 m high and is founded on a piled raft floating in a thick layer of soft pyroclastic and alluvial soils. On the basis of a conventional subsoil classification, the inertial seismic actions on the building would lead to expensive measures for seismic retrofitting. By contrast, if site effects and soil–structure interaction are adequately addressed the picture is completely different. First, free-field seismic response analyses highlighted the beneficial effects of a peat layer, acting as a natural damper on the propagation of shear waves. Finiteelement analyses of pile–soil kinematic interaction were then carried out to define the foundation input motion, which was found not to be significantly affected. The effects of inertial interaction were evaluated accounting for soil–foundation compliance; they resulted in an increase of the structural period of vibration, while the overall damping did not change compared to that of the fixed-base structure. The increased structural period led to further reduction of spectral acceleration. The results could lead to significant impacts on the seismic assessment of slender buildings founded on piles embedded in deformable soils

Effects of dynamic soil-structure interaction on the seismic performance of a tall building founded on piles

A tall r.c. building in the city of Napoli has recently undergone a seismic vulnerability assessment, in order to satisfy its public function fulfilling the requirements of the new Italian Building Code. The study is focused on the inertial response of the building, accounting for soil deformability and damping. To this aim, the overall structure is idealized as a simple oscillator supported on frequency-dependent springs and dashpots

Pulmonary transit of sonicated albumin microbubbles during controlled mechanical ventilation: a transthoracic echocardiographic study.

Air-filled human serum albumin microspheres are ultrasonic contrast tracers that pass through the right ventricle, traverse the lungs, and effectively opacify the left heart chambers in spontaneously breathing patients. In this clinical study, we assessed whether they also do so in anesthetized patients during and after mechanical ventilation. In 20 anesthetized patients undergoing intermittent positive pressure ventilation (IPPV) for elective peripheral neurosurgical procedures, a sonicated ultrasound contrast drug (0.06 mL/kg) was injected TV before inducing anesthesia in spontaneously breathing patients (baseline), during IPPV, and 5 and 30 min after tracheal extubation. Transthoracic echocardiograms were obtained in the four-chamber apical view and were recorded for off-line analysis. Time to contrast appearance in the right ventricle and pulmonary transit time were measured in cardiac cycles. The peak intensity of right and left ventricular chamber opacification were scored on a scale ranging from 1 (no contrast or traces only) to 5 (attenuation). After each injection, the time for contrast appearance in the right ventricle was similar in all patients. Pulmonary transit time increased significantly during IPPV and was normal 5 min and 30 min after extubation. Right ventricular chamber opacification achieved high-grade intensity and remained constant before, during, and after IPPV. Conversely, although the baseline contrast injection resulted in high-grade left ventricular chamber opacification, the intensity decreased significantly during IPPV, remained low 5 min after extubation, and was normalized 30 min after extubation. Implications: During intermittent positive pressure ventilation, TV sonicated albumin microbubbles pass through the lungs poorly and inefficiently opacify the left ventricle compared with the effects observed during spontaneous ventilation

Effetti della risposta locale e dell'interazione terreno-struttura sulle azioni sismiche di progetto di un edificio alto

Gli effetti prodotti da un terremoto sugli edifici dipendono da una moltitudine di fattori, fra i quali le caratteristiche del moto sismico, la stratigrafia e le proprietà meccaniche dei terreni, la tipologia e la rigidezza delle fondazioni e della stessa struttura in elevazione. Un esempio paradigmatico in questo senso è rappresentato da un edificio alto circa 110 m nel Centro Direzionale di Napoli fondato su una palificata progettata in modo convenzionale su terreni vulcanici ed alluvionali deformabili. L’analisi della risposta sismica locale mostra che il moto sismico di free-field in superficie dipende fortemente dal dettaglio stratigrafico, soprattutto nell’intervallo di valori del periodo strutturale di interesse per la tipologia di edificio presa in esame. Nel medesimo intervallo, invece, la modifica del moto sismico free-field dovuta all’interazione cinematica palificata-terreno non produce significativi effetti di filtraggio delle azioni sismiche trasmesse in elevazione. La valutazione dell’interazione inerziale, pur se in forma semplificata, permette invece di apprezzare ulteriori significative riduzioni dell’azione sismica in elevazione per effetto della deformabilità della fondazione. I risultati possono costituire un elemento di orientamento, di carattere più generale, per la verifica sismica di edifici alti fondati su palificate in terreni deformabili