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• Four models aim to predict pre-treatment rebleeding after aneurysmal subarachnoid hemorrhage. • We assessed each for risk of bias and clinical applicability using validated tools. • No single model demonstrated a low risk of bias and low applicability concerns in all domains. • No existing model can be recommended for clinical use in their current state. • Future studies revising current models or formulating new ones are needed. Pre-treatment rebleeding following aneurysmal subarachnoid hemorrhage (aSAH) increases the risk of death and a poor neurological outcome. Current guidelines recommend aneurysm treatment "as early as feasible after presentation, preferably within 24 h of onset" to mitigate this risk, a practice termed ultra-early treatment. However, ongoing debate regarding whether ultra-early treatment is independently associated with reduced re-bleeding risk, together with the recognition that re-bleeding occurs even in centres practicing ultra-early treatment due to the presence of other risk-factors has resulted in a renewed need for patient-specific re-bleed risk prediction. Here, we systematically review models which seek to provide patient specific predictions of pre-treatment rebleeding risk. Following registration on the International prospective register of systematic reviews (PROSPERO) CRD 42023421235; Ovid Medline (Pubmed), Embase and Googlescholar were searched for English language studies between 1st May 2002 and 1st June 2023 describing pre-treatment rebleed prediction models following aSAH in adults ≥18 years. Of 763 unique records, 17 full texts were scrutinised with 5 publications describing 4 models reviewed. We used the semi-automated template of Fernandez-Felix et al. incorporating the Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies (CHARMS) checklist and the Prediction model Risk Of Bias ASsessment Tool (PROBAST) for data extraction, risk of bias and clinical applicability assessment. To further standardize risk of bias and clinical applicability assessment, we also used the published explanatory notes for the PROBAST tool and compared the aneurysm treatment practices each prediction model's formulation cohort experienced to a prespecified benchmark representative of contemporary aneurysm treatment practices as outlined in recent evidence-based guidelines and published practice pattern reports from four developed countries. Reported model discriminative performance varied between 0.77 and 0.939, however, no single model demonstrated a consistently low risk of bias and low concern for clinical applicability in all domains. Only the score of Darkwah Oppong et al. was formulated using a patient cohort in which the majority of patients were managed in accordance with contemporary, evidence-based aneurysm treatment practices defined by ultra-early and predominantly endovascular treatment. However, this model did not undergo calibration or clinical utility analysis and when applied to an external cohort, its discriminative performance was substantially lower that reported at formulation. No existing prediction model can be recommended for clinical use in centers practicing contemporary, evidence-based aneurysm treatment. There is a pressing need for improved prediction models to estimate and minimize pre-treatment re-bleeding risk. [ABSTRACT FROM AUTHOR]

• A device for testing the ultra-early tensile creep of cement paste was designed. • The tensile creep test of cement paste specimens was carried out by means of tensile test with mold and graded incremental loading. • Tensile creep tests of cement pastes with water cement ratio of 0.25, 0.3 and 0.35 were carried out at ulter-early age. • Characterization of Ultr-Early Tensile Creep of Cement Paste by Variable Viscosity Dashpot Element. • In logarithmic coordinate system, there is a linear relationship between initial viscosity of cement paste and loading age. Tensile creep releases the internal tensile stress caused by the restriction of internal deformation in cement-based structure at ultra-early age (from initial setting to final setting) and thus reduces the risk of cracking under tension. However, the tensile creep measurement at that age is challenging due to insufficient strength of specimens. Therefore, a test device for measuring the tensile creep of ultra-early age cement paste was designed in this study, which applied multilevel incremental tensile load on the ultra-early age cement paste in a tailored molud. The effect of water-cement ratio and loading age on the ultra-early was studied using that device. The results revealed that the specific creep of ultra-early cement paste decreases exponentially with the increase of loading age, while increases with the increase of water-cement ratio. The ultra-early tensile creep of cement paste was characterized by variable viscosity dashpot element. Moreover, the increase rate of viscosity with time under external force was found equal to the creep modulus of cement paste, and in the logarithmic coordinate system, there is a linear relationship between the initial viscosity of cement paste and the loading age. [ABSTRACT FROM AUTHOR]

Objective: To determine if ultra-early (<24 h) venous thromboembolism (VTE) prophylaxis was associated with hematoma growth in spontaneous intracerebral hemorrhage (ICH).Background: Patients with ICH have a high risk of VTE. Pharmacological prophylaxis such as unfractionated heparin (UFH) have been demonstrated to reduce VTE. However, published datasets exclude patients with recent ICH out of concern for hematoma enlargement. American Heart/Stroke Association guidelines recommend UFH 1-4 days after hematoma stabilization while the European Stroke Organization has no recommendations on when to begin UFH. Our institutional practice is to obtain stability CT scans at 6 to 24 h and to begin UFH following documented clinical and radiologic stability. We examined the impact of this practice on hematoma expansion.Methods: We performed a retrospective cohort analysis of consecutive ICH patients treated at a single tertiary academic referral center in the US. Demographic and clinical characteristics were abstracted. ICH volume was measured via 3D volumetrics for a CT head done on admission, follow-up stability, and prior to discharge. The primary outcome was analyzed as ≥3 mL hematoma enlargement. Secondary outcomes include hematoma expansion of ≥6mL and ≥ 33%, length of stay (LOS), discharge disposition and mortality.Results: A total of 163 ICH patients were analyzed. There were 58 (35.6%) patients in the ultra-early UFH group and UFH was initiated on average at 13.8 h from initial scan. There were 105 (64.6%) patients in the standard group who initiated UFH at an average of 46.6 h. The primary outcome of hematoma enlargement ≥3 mL was observed in 2/58(3.4%) patients with ultra-early initiation of UFH and in 7/105(6.7%) in the standard group (p=0.49). Secondary outcomes were not significant including hematoma expansion in the ultra-early group ≥ 6 mL 3/58 (5.2%) and ≥33% 7/58 (12.1%) (p=0.91, 0.61, respectively) as well as mortality or LOS.Conclusion: Venous thromboembolism prophylaxis started ultra-early (≤24 h) after ICH was not associated with hematoma expansion. [ABSTRACT FROM AUTHOR]

Background Ultra-early surgical clot removal relieves mechanical compression on adjacent normal brain tissue and limits the toxic effects of a hematoma, which might improve the outcomes in patients with intracerebral hemorrhage (ICH); however, hematoma expansion frequently occurs within 20 hours after the ictus, and this limits the use of ultra-early surgery. Computed tomography angiography spot sign was recently validated as an important predictor of hematoma expansion in patients with ICH. Methods Fifty-nine patients with ICH and negative spot sign who received ultra-early stereotactic aspiration (<6 hours after ictus; n = 32 [Ultra-early group]) or routine stereotactic aspiration (≥6 hours after ictus; n = 27 [Routine group]) were included in retrospective analysis. Results The percentage of rebleeding was not significantly different between the 2 groups. Perihematoma edema 7 days after surgery in the Ultra-early group was significantly less frequent than that in the Routine group. For long-term outcomes, the proportion of patient fatalities and Glasgow Outcome Scale score were not significantly different between the 2 groups; however, for patients with severe symptoms, the rate of good neurological outcome in the Ultra-early group was higher than that in the Routine group. Conclusions Ultra-early stereotactic aspiration might decrease the volume of perihematoma edema and improve the functional outcomes to some extent, without increasing the recurrence of ICH and patient fatalities. Our findings suggest that using negative spot sign as an indicator for performing ultra-early stereotactic aspiration could be a safe and effective protocol for ICH patients. [ABSTRACT FROM AUTHOR]