Time-to-care metrics in patients with interhospital transfer for mechanical thrombectomy in north-east Germany: primary telestroke centers in rural areas vs. primary stroke centers in a metropolitan area.

BACKGROUND: Mechanical thrombectomy (MT) is highly effective in large vessel occlusion (LVO) stroke. In north-east Germany, many rural hospitals do not have continuous neurological expertise onsite and secondary transport to MT capable comprehensive stroke centers (CSC) is necessary. In metropolitan areas, small hospitals often have neurology departments, but cannot perform MT. Thus, interhospital transport to CSCs is also required. Here, we compare time-to-care metrics and outcomes in patients receiving MT after interhospital transfer from primary stroke centers (PCSs) to CSCs in rural vs. metropolitan areas. METHODS: Patients from ten rural telestroke centers (RTCs) and nine CSCs participated in this study under the quality assurance registry for thrombectomies of the Acute Neurological care in North-east Germany with TeleMedicine (ANNOTeM) telestroke network. For the metropolitan area, we included patients admitted to 13 hospitals without thrombectomy capabilities (metropolitan primary stroke centers, MPSCs) and transferred to two CSCs. We compared groups regarding baseline variables, time-to-care metrics, clinical, and technical outcomes. RESULTS: Between October 2018 and June 2022, 50 patients were transferred from RTCs within the ANNOTeM network and 42 from MPSCs within the Berlin metropolitan area. RTC patients were older (77 vs. 72 yrs, p = 0.05) and had more severe strokes (NIHSS 17 vs. 10 pts., p < 0.01). In patients with intravenous thrombolysis (IVT; 34.0 and 40.5%, respectively), time from arrival at the primary stroke center to start of IVT was longer in RTCs (65 vs. 37 min, p < 0.01). However, RTC patients significantly quicker underwent groin puncture at CSCs (door-to-groin time: 42 vs. 60 min, p < 0.01). Despite longer transport distances from RTCs to CSCs (55 vs. 22 km, p < 0.001), there was no significant difference of times between arrival at the PSC and groin puncture (210 vs. 208 min, p = 0.96). In adjusted analyses, there was no significant difference in clinical and technical outcomes. CONCLUSION: Despite considerable differences in the setting of stroke treatment in rural and metropolitan areas, overall time-to-care metrics were similar. Targets of process improvement should be door-to-needle times in RTCs, transfer organization, and door-to-groin times in CSCs wherever such process times are above best-practice models

Stroke admissions, stroke severity, and treatment rates in urban and rural areas during the COVID-19 pandemic

Background: Many regions worldwide reported a decline of stroke admissions during the early phase of the coronavirus disease 2019 (COVID-19) pandemic. It remains unclear whether urban and rural regions experienced similar declines and whether deviations from historical admission numbers were more pronounced among specific age, stroke severity or treatment groups.Methods: We used registry datasets from (a) nine acute stroke hospitals in Berlin, and (b) nine hospitals from a rural TeleNeurology network in Northeastern Germany for primary analysis of 3-week-rolling average of stroke/TIA admissions before and during the COVID-19 pandemic. We compared course of stroke admission numbers with regional cumulative severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) infections. In secondary analyses, we used emergency department logs of the Berlin Charite University hospital to investigate changes in age, stroke severity, and thrombolysis/thrombectomy frequencies during the early regional Sars-CoV-2 spread (March and April 2020) and compared them with preceding years.Results: Compared to past years, stroke admissions decreased by 20% in urban and 20-25% in rural hospitals. Deviations from historical averages were observable starting in early March and peaked when numbers of regional Sars-CoV-2 infections were still low. At the same time, average admission stroke severity and proportions of moderate/severe strokes (NIHSS >5) were 20 and 20-40% higher, respectively. There were no relevant deviations observed in proportions of younger patients (<65 years), proportions of patients with thrombolysis, or number of thrombectomy procedures. Stroke admissions at Charite subsequently rebounded and reached near-normal levels after 4 weeks when the number of new Sars-CoV-2 infections started to decrease.Conclusions: During the early pandemic, deviations of stroke-related admissions from historical averages were observed in both urban and rural regions of Northeastern Germany and appear to have been mainly driven by avoidance of admissions of mildly affected stroke patients.Clinical epidemiolog

Self-productivity and complementarities in human development : evidence from MARS

This paper investigates the role of self-productivity and home resources in capability formation from infancy to adolescence. In addition, we study the complementarities between basic cognitive, motor and noncognitive abilities and social as well as academic achievement. Our data are taken from the Mannheim Study of Children at Risk (MARS), an epidemiological cohort study following the long-term outcome of early risk factors. Results indicate that initial risk conditions cumulate and that differences in basic abilities increase during development. Self-productivity rises in the developmental process and complementarities are evident. Noncognitive abilities promote cognitive abilities and social achievement. There is remarkable stability in the distribution of the economic and socio-emotional home resources during the early life cycle. This is presumably a major reason for the evolution of inequality in human development

Intravenous Thrombolysis and Passes of Thrombectomy as Predictors for Endovascular Revascularization in Ischemic Stroke.

Patient selection for endovascular revascularization treatment (ERT) in acute ischemic stroke depends on the expected benefit-risk ratio. As rapid revascularization is a major determinant of good functional outcome, we aimed to identify its predictors after ERT. Consecutive stroke patients from a single stroke center with distal internal carotid artery-, proximal middle cerebral artery- or T-occlusions treated with ERT were retrospectively selected. We assessed admission noncontrast computed tomography and computed tomography angiography for thrombus location, thrombus load (clot burden score), and collateral status. Clinical data were extracted from medical charts. Univariate and multivariate regression analyses were performed to identify predictors of revascularization (thrombolysis in cerebral infarction ≥2b) after ERT. A total of 63 patients were identified (median age, 73 years; interquartile range: 62-77; 40 females). Sixteen patients (25.4%) underwent intravenous thrombolysis (ivT) before ERT. Twenty-two patients (34.9%) had additional intra-arterial application of recombinant tissue plasminogen activator. The overall recanalization rate was 66.7%, and 9.5% had symptomatic intracranial bleeding. In-hospital mortality was 15%, and 30% reached good functional outcome at discharge. In the univariate analysis, preceding ivT and the number of passes for thrombectomy (dichotomized ≤2 versus &gt;2) were associated with recanalization. There was a trend for number of thrombectomy passes (as continuous variable) and multimodal ERT. In the multivariate regression analysis, ivT prior to ERT and passes of thrombectomy were identified as independent predictors for recanalization. ivT and lower passes of thrombectomy are associated with recanalization after ERT for ischemic stroke with proximal vessel occlusions

Inter-rater Agreement in Three Perfusion-Computed Tomography Evaluation Methods before Endovascular Therapy for Acute Ischemic Stroke.

There is ongoing debate on which method of perfusion computed tomography (PCT) evaluation in ischemic stroke is the most appropriate for improved selection of patients for endovascular treatment. We sought to test different assessment methods for inter-rater reliability. Twenty-six patients were enrolled prospectively before endovascular therapy for acute anterior circulation ischemic stroke. Three raters experienced in stroke imaging and blinded to other imaging and clinical information independently analyzed 22 technically successful PCT scans according to 3 prespecified assessment methods applied to cerebral blood flow (CBF)/cerebral blood volume (CBV) and time-to-peak (TTP) maps: (1) visual mismatch estimate (VME), (2) Alberta Stroke Program Early CT Score perfusion method (ASPECTS-PCT), and (3) quantitative perfusion ratios (qPRs): RCBF, RCBV, RTTP. Inter-rater agreement was assessed with Cohen's kappa, intraclass correlation coefficients (ICC), Bland-Altman plots, and global and descriptive statistics. Significant differences between raters were found with VME and ASPECTS-PCT (P &lt; .001) but with qPRs only for CBV (P = .03). Inter-rater agreement for VME was at best moderate by kappa statistics (.51); moderate by ICC for all parametric maps of ASPECTS-PCT (.56-.62), strong for RTTP (.76), and excellent for RCBF (.92) and RCBV (.86). Pairwise comparisons revealed less scattering of individual values with qPRs and less deviation of mean differences from 0, suggesting minor systematic deviation by any 1 rater as compared with VME or ASPECTS-PCT. PCT evaluation methods used before endovascular therapy for acute anterior circulation stroke are subject to substantial inter-rater disagreement. QPRs in PCT evaluation had better inter-rater reliability than the often used VME and ASPECTS-PCT assessment

CYCLIC SILYLHYDRAZINES AND THEIR BORANE ADDUCTS

Mitzel NW, HOFMANN M, ANGERMAIER K, SCHIER A, SCHLEYER PV, SCHMIDBAUR H. CYCLIC SILYLHYDRAZINES AND THEIR BORANE ADDUCTS. INORGANIC CHEMISTRY. 1995;34(19):4840-4845.A series of five-, six-, and seven-membered cyclic silylhydrazines have been prepared from the reactions of 1,2-bis(bromosilyl)ethane and 1,3-bis(bromosilyl)propane with 1,1-dimethylhydrazine [leading to 1-(dimethylamino)-1-aza-2,5-disilacyclopentane (3) and 1-(dimethylamino)-1-aza-2,6-disilacyclohexane (4)] and 1,2-dimethylhydrazine [leading to 1,2-dimethyl-1,2-diaza-3,6-disilacyclohexane (7) and 1,2-dimethyl-1,2-diaza-2,7-disilacycloheptane (8)] in the presence of triethylamine, respectively. The compounds with endocyclic Si-N-Si units (3, 4) are found to be stable for long periods of time, while those with Si-N-N-Si units (7, 8) decompose within a few days at ambient temperature. Compounds 3 and 4 have been reacted with the Lewis acid BH3 to give the dimethylamine-borane adducts 5 and 6. All compounds have been fully characterized by spectroscopic data [IR, MS, NMR (H-1, C-13, N-15, Si-29)]. Single crystals of 5 [6] grown from the melt and studied by low-temperature X-ray diffraction analyses are orthorhombic, space group Pbca (No. 61), with a = 11.385(1) [13.300 (1)] Angstrom, b = 9.938(1) [9.837(1)] Angstrom, c = 17.156(1) [16.364(1)] Angstrom, d(calc) = 1.096 (1.081) g cm(-3), and Z = 8 [8]. In both compounds, the BH3 unit is bound to the nonsilylated nitrogen atom, indicating the reduction of the basicity of nitrogen by Si substitution. The silylated nitrogen atoms show planar coordination, while the borylated amine unit is tetrahedrally coordinated. From a comparison of the ring geometries of 5 and 6 with known open-chain structures, it appears that the C2Si2N ring system of 5 is clearly more strained than that of 6 (C3Si2N) This argument also offers an explanation for the preferred formation of the compounds 1,6-diaza-2,5,7,10-tetrasila-[4.4.0]bicyclodecane (1) and bi(1-aza-2,6-disilacyclohexyl) (2) as compared to their isomers with different ring sizes. The relative stabilities of these isomers in question have been quantified by ab initio (MP2(fc)/6-31G*) calculations of geometries and energies of the systems [(CH2)(n)(SiH2)]N-N[(SiH2)(CH2)(n)] versus the annelated molecules (CH2)(n)(SiH2)N-2(CH2)(n)(SiH2) with n = 1-3. These results show the annelated isomers (ring enlarged) to be lower in energy for n = 1 and 2, while for n = 3 the N-N bridged nonannelated isomer is preferred