scholarly journals Early cisternal fibrinolysis is more effective than rescue spasmolysis for the prevention of delayed infarction after subarachnoid haemorrhage

2021 ◽  
pp. svn-2021-001146
Author(s):  
Roland Roelz ◽  
Christian Scheiwe ◽  
Jürgen Grauvogel ◽  
Istvan Csok ◽  
Volker Arnd Coenen ◽  
...  
Keyword(s):  
Subarachnoid Haemorrhage ◽  
Preventive Intervention ◽  
Rescue Therapy ◽  
Aneurysmal Subarachnoid Haemorrhage ◽  
Blood Clearance ◽  
Mean Flow ◽  
Registration Number ◽  
Risk Patients ◽  
The Mean ◽  
Treatment Onset

BackgroundTo compare the efficacy of two different concepts of cisternal therapy—PREVENTIVE fibrinolysis plus on-demand spasmolysis versus RESCUE spasmolysis—for the prevention of cerebral vasospasm (CVS) and delayed cerebral infarction (DCI) in patients with aneurysmal subarachnoid haemorrhage (aSAH).MethodsRetrospective analysis of 84 aSAH patients selected for cisternal therapy for DCI prevention. 66 high-risk patients received PREVENTIVE cisternal therapy to enhance blood clearance. Either stereotactic catheter ventriculocisternostomy (STX-VCS) or intraoperative placement of a cisterno-ventriculostomy catheter (CVC), followed by fibrinolytic cisternal lavage using urokinase was performed. In case of vasospasm, nimodipine was applied intrathecally. 22 low-risk patients who developed CVS against expectations were selected for STX-VCS as RESCUE intervention for cisternal spasmolysis with nimodipine. Rates of DCI and mean flow velocities of daily transcranial Doppler (TCD) ultrasonographies were evaluated.ResultsDespite a higher prespecified DCI risk, patients selected for PREVENTIVE intervention primarily aiming at blood clearance had a lower DCI rate compared with patients selected for intrathecal spasmolysis as a RESCUE therapy (11.3% vs 18.2%). After intrathecal treatment onset, CVS (TCD>160 cm/s) occurred in 45% of patients with PREVENTIVE and 77% of patients with RESCUE therapy (p=0.013). A stronger response of CVS to intrathecal nimodipine was observed in patients with PREVENTIVE intervention as the mean CVS duration after start of intrathecal nimodipine was 3.2 days compared with 5.8 days in patients with RESCUE therapy (p=0.026).ConclusionsPREVENTIVE cisternal therapy directed at blood clearance is more effective for the prevention of CVS and delayed infarction compared with cisternal RESCUE spasmolysis.Trial registration numberDRKS00016532.

scholarly journals Complications of external cerebrospinal fluid drainage in aneurysmal subarachnoid haemorrhage

2021 ◽  
Author(s):  
Sebastian Arts ◽  
Erik J. van Lindert ◽  
Rene Aquarius ◽  
Ronald H. M. A. Bartels ◽  
Hieronymus D. Boogaarts
Keyword(s):  
Cerebrospinal Fluid ◽  
Subarachnoid Haemorrhage ◽  
Demographic Data ◽  
Poisson Model ◽  
Medical Complications ◽  
Aneurysmal Subarachnoid Haemorrhage ◽  
Academic Hospital ◽  
Complication Risk ◽  
External Drain ◽  
The Mean

Abstract Background The need for external cerebrospinal fluid (CSF) drains in aneurysmal subarachnoid haemorrhage (aSAH) patients is common and might lead to additional complications. Objective A relation between the presence of an external CSF drain and complication risk is investigated. Methods A prospective complication registry was analysed retrospectively. We included all adult aSAH patients admitted to our academic hospital between January 2016 and January 2018, treated with an external CSF drain. Demographic data, type of external drain used, the severity of the aSAH and complications, up to 30 days after drain placement, were registered. Complications were divided into (1) complications with a direct relation to the external CSF drain and (2) complications that could not be directly related to the use of an external CSF drain referred to as medical complications Results One hundred and forty drains were implanted in 100 aSAH patients. In total, 112 complications occurred in 59 patients. Thirty-six complications were drain related and 76 were medical complications. The most common complication was infection (n = 34). Drain dislodgement occurred 16 times, followed by meningitis (n = 11) and occlusion (n = 9). A Poisson model showed that the mean number of complications raised by 2.9% for each additional day of drainage (95% CI: 0.6–5.3% p = 0.01). Conclusion Complications are common in patients with aneurysmal subarachnoid haemorrhage of which 32% are drain-related. A correlation is present between drainage period and the number of complications. Therefore, reducing drainage period could be a target for further improvement of care.

A cluster-controlled clinical trial of two prophylactic silicone sacral dressings to prevent sacral pressure injuries in critically ill patients

2019 ◽  
pp. 21-26 ◽  
Author(s):  
Monica Stankiewicz ◽  
Jodie Gordon ◽  
Joel Dulhunty ◽  
Wendy Brown ◽  
Hamish Pollock ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Intensive Care ◽  
Similar Efficacy ◽  
Care Patient ◽  
Controlled Clinical Trial ◽  
Cost Difference ◽  
Increased Risk ◽  
Pressure Injury ◽  
Risk Patients ◽  
The Mean

Objective Patients in the intensive care unit (ICU) have increased risk of pressure injury (PI) development due to critical illness. This study compared two silicone dressings used in the Australian ICU setting for sacral PI prevention. Design A cluster-controlled clinical trial of two sacral dressings with four alternating periods of three months' duration. Setting A 10-bed general adult ICU in outer-metropolitan Brisbane, Queensland, Australia. Participants Adult participants who did not have a sacral PI present on ICU admission and were able to have a dressing applied for more than 24 hours without repeated dislodgement or soiling in a 24-hour period (>3 times). Interventions Dressing 1 (Allevyn Gentle Border Sacrum™, Smith & Nephew) and Dressing 2 (Mepilex Border Sacrum™, Mölnlycke). Main outcomes measures The primary outcome was the incidence of a new sacral PI (stage 1 or greater) per 100 dressing days in the ICU. Secondary outcomes were the mean number of dressings per patient, the cost difference of dressings to prevent a sacral PI and product integrity. Results There was no difference in the incidence of a new sacral PI (0.44 per 100 dressing days for both products, p = 1.00), the mean number of dressings per patient per day (0.50 for both products, p = 0.51) and product integrity (85% for Dressing 1 and 84% for Dressing 2, p = 0.69). There was a dressing cost difference per patient (A$10.29 for Dressing 1 and A$28.84 for Dressing 2, p < 0.001). Conclusions Similar efficacy, product use and product integrity, but differential cost, were observed for two prophylactic silicone dressings in the prevention of PIs in the intensive care patient. We recommend the use of sacral prophylactic dressings for at-risk patients, with the choice of product based on ease of application, clinician preference and overall cost-effectiveness of the dressing.

Simple explicit model of liquid mean flow in region above axial impeller

1985 ◽  
Vol 50 (11) ◽  
pp. 2396-2410
Author(s):  
Miloslav Hošťálek ◽  
Ivan Fořt
Keyword(s):  
Vortex Flow ◽  
Flow Model ◽  
Quantitative Agreement ◽  
Mean Flow ◽  
Flat Bottom ◽  
Proposed Model ◽  
Minimum Number ◽  
The Mean ◽  
Model Equations ◽  
Radial Circulation

The study describes a method of modelling axial-radial circulation in a tank with an axial impeller and radial baffles. The proposed model is based on the analytical solution of the equation for vortex transport in the mean flow of turbulent liquid. The obtained vortex flow model is tested by the results of experiments carried out in a tank of diameter 1 m and with the bottom in the shape of truncated cone as well as by the data published for the vessel of diameter 0.29 m with flat bottom. Though the model equations are expressed in a simple form, good qualitative and even quantitative agreement of the model with reality is stated. Apart from its simplicity, the model has other advantages: minimum number of experimental data necessary for the completion of boundary conditions and integral nature of these data.

scholarly journals Technical note: Inherent benchmark or not? Comparing Nash–Sutcliffe and Kling–Gupta efficiency scores

2019 ◽  
Vol 23 (10) ◽  
pp. 4323-4331 ◽  
Author(s):  
Wouter J. M. Knoben ◽  
Jim E. Freer ◽  
Ross A. Woods
Keyword(s):  
Time Series ◽  
Coefficient Of Variation ◽  
Ad Hoc ◽  
Model Performance ◽  
Technical Note ◽  
Mean Flow ◽  
Model Adequacy ◽  
Robust Model ◽  
The Mean ◽  
Adequacy Assessment

Abstract. A traditional metric used in hydrology to summarize model performance is the Nash–Sutcliffe efficiency (NSE). Increasingly an alternative metric, the Kling–Gupta efficiency (KGE), is used instead. When NSE is used, NSE = 0 corresponds to using the mean flow as a benchmark predictor. The same reasoning is applied in various studies that use KGE as a metric: negative KGE values are viewed as bad model performance, and only positive values are seen as good model performance. Here we show that using the mean flow as a predictor does not result in KGE = 0, but instead KGE =1-√2≈-0.41. Thus, KGE values greater than −0.41 indicate that a model improves upon the mean flow benchmark – even if the model's KGE value is negative. NSE and KGE values cannot be directly compared, because their relationship is non-unique and depends in part on the coefficient of variation of the observed time series. Therefore, modellers who use the KGE metric should not let their understanding of NSE values guide them in interpreting KGE values and instead develop new understanding based on the constitutive parts of the KGE metric and the explicit use of benchmark values to compare KGE scores against. More generally, a strong case can be made for moving away from ad hoc use of aggregated efficiency metrics and towards a framework based on purpose-dependent evaluation metrics and benchmarks that allows for more robust model adequacy assessment.

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