Development and application of a tsunami fragility curve of the 2015 tsunami in Coquimbo, Chile

The last earthquake that affected the city of Coquimbo took place in September 2015 and had a magnitude of Mw = 8.3, resulting in localized damage in low-lying areas of the city. In addition, another seismic gap north of the 2015 earthquake rupture area has been identified; therefore, a significant earthquake (Mw = 8.2 to 8.5) and tsunami could occur in the near future. The present paper develops a tsunami fragility curve for the city of Coquimbo based on field survey data and tsunami numerical simulations. The inundation depth of the 2015 Chile tsunami in Coquimbo was estimated by means of numerical simulation with the Non-hydrostatic Evolution of Ocean WAVEs (NEOWAVE) model and five nested grids with a maximum grid resolution of 10m. The fragility curve exhibited behavior similar to that of other curves in flat areas in Japan, where little damage was observed at relatively high inundation depths. In addition, it was observed that Coquimbo experienced less damage than Dichato (Chile); in fact, at an inundation depth of 2m, Dichato had a  ∼ 75% probability of damage, while Coquimbo proved to have only a 20% probability. The new fragility curve was used to estimate the damage by possible future tsunamis in the area. The damage assessment showed that  ∼ 50% of the structures in the low-lying area of Coquimbo have a high probability of damage in the case of a tsunami generated off the coast of the study area if the city is rebuilt with the same types of structures

Combination of school evacuation drill with tsunami inundation simulation: Consensus-making between disaster experts and citizens on an evacuation strategy

This paper aims to introduce an effective methodology for communicating a science-based tsunami risk scenario to non-expert citizens through consensus-making between disaster experts and non-experts, with the aid of four-way split-screen movie clips depicting evacuation scenarios. Action research on tsunami education in Zihuatanejo, Mexico found that a perception of tsunamis as catastrophic together with the one-directional nature of risk communication resulted in inaction on the part of non-experts in disaster preparedness, contrary to the expectations of experts. In other words, non-experts did not think that they could cope with a tsunami disaster and they perceived that as non-experts they themselves could not affect the tsunami risk scenario communicated to them by the experts. In response, movie clips simultaneously displaying a school evacuation drill and tsunami inundation simulation were developed. These movie clips are intended to serve as a tool in the process of establishing a school tsunami evacuation strategy by promoting consensus-making between experts and non-experts about the risk scenario, thereby helping to change the perception of a tsunami from a catastrophe that cannot be dealt with by non-experts to a realistic perception that non-experts can indeed help by engaging in their own tsunami risk preparedness activities. The developed movie clips were used at a workshop for stakeholders, including academics, local government, and teachers, with the aims of establishing scenario-based evacuation strategies and promoting the proactive implementation of preparedness activities by non-expert teachers. The study will contribute to establishing a mechanism for applying scientific knowledge to solving societal issues

Method to extract difficult-to-evacuate areas by using tsunami evacuation simulation and numerical analysis

Extracting the area where people have difficulty evacuating (hereafter difficult-to-evacuate areas, DEA) when tsunamis hit after an earthquake is important for effective disaster mitigation measures. The DEA was conven-tionally extracted by simply considering the walking speed, distance to the evacuation destination, and time needed for evacuation after considering the estimated tsunami inundation area. However, evaluating the DEA from such a simple scheme is insufficient because the behavior of residents and the road conditions to the evacuation destinations after an earthquake are not properly reflected in the scheme. In this study, agent-based tsunami evacuation simulations that can reflect the behavior of residents and real -time changes in the situation were conducted in Zihuatanejo, Guerrero, Mexico. It is a prime sightseeing destination under the high risk of megathrust events in the Guerrero Gap. First, by checking the simulation images at the tsunami arrival time, bottleneck locations were identified, and five additional models with different measures for the bottleneck locations were constructed and tested to find the best model with 195 casualties. Then, focusing on the best model, three indices for the casualties were proposed to extract the DEA effectively and quantitatively, and numerical analyses using the three indices was conducted. Finally, the subdistrict in the center of the target area (subdistrict 5) was quantitatively found to be the district that should be given the highest priority for measures. Moreover, an example model with a new measure in subdistrict 5 was validated to have 101 casualties. The key points for applying the proposed method for extraction of DEA in other areas are summarized

High-dose-rate brachytherapy in the treatment of skin Kaposi sarcoma

Purpose : The aim of the study is to review our experience in treatment of Kaposi sarcoma (KS) lesions with high-dose-rate (HDR) brachytherapy. Material and methods : We present five new KS lesions (three patients) that were treated in our hospital from May 2016 to February 2017 with HDR brachytherapy using Valencia applicators. The treatment was delivered in 5 Gy fractions over five sessions, on alternate days. Total dose of 25 Gy (EQD2 31.25 Gy) was delivered. All patients were male, Caucasian, without a history of HIV, organ transplantation, or current immunosuppressive therapy. The median age was 76 years. Results : All lesions (100%) were located in lower limbs (60% in the ankle, 20% in the leg, and 20% in the foot), and their development was progressive. No lesion was greater than 2 cm (range, 0.5-1.5 cm). With a median follow-up of 15 months, all patients had a complete response to the treatment, with no evidence of local recurrence or tumor progression. Most of the patients (80%) had no acute toxicity; only one patient developed erythema grade 2. Conclusions : HDR brachytherapy could be a good option of treatment for these types of lesions, especially in elderly patients, or when cosmetic results are not good after surgery. Brachytherapy with the Valencia applicator, using hypofractionated regimen provides excellent results in terms of cosmetic and local control, and furthermore, facilitates treatment compliance, which is very relevant in elderly patients. HDR brachytherapy offers a simple, safe, quick, and attractive non-surgical treatment option

Intravenous thrombolysis or endovascular therapy for acute ischemic stroke associated with cervical internal carotid artery occlusion: the ICARO-3 study

The aim of the ICARO-3 study was to evaluate whether intra-arterial treatment, compared to intravenous thrombolysis, increases the rate of favourable functional outcome at 3 months in acute ischemic stroke and extracranial ICA occlusion. ICARO-3 was a non-randomized therapeutic trial that performed a non-blind assessment of outcomes using retrospective data collected prospectively from 37 centres in 7 countries. Patients treated with endovascular treatment within 6 h from stroke onset (cases) were matched with patients treated with intravenous thrombolysis within 4.5 h from symptom onset (controls). Patients receiving either intravenous or endovascular therapy were included among the cases. The efficacy outcome was disability at 90 days assessed by the modified Rankin Scale (mRS), dichotomized as favourable (score of 0-2) or unfavourable (score of 3-6). Safety outcomes were death and any intracranial bleeding. Included in the analysis were 324 cases and 324 controls: 105 cases (32.4 %) had a favourable outcome as compared with 89 controls (27.4 %) [adjusted odds ratio (OR) 1.25, 95 % confidence interval (CI) 0.88-1.79, p = 0.1]. In the adjusted analysis, treatment with intra-arterial procedures was significantly associated with a reduction of mortality (OR 0.61, 95 % CI 0.40-0.93, p = 0.022). The rates of patients with severe disability or death (mRS 5-6) were similar in cases and controls (30.5 versus 32.4 %, p = 0.67). For the ordinal analysis, adjusted for age, sex, NIHSS, presence of diabetes mellitus and atrial fibrillation, the common odds ratio was 1.15 (95 % IC 0.86-1.54), p = 0.33. There were more cases of intracranial bleeding (37.0 versus 17.3 %, p = 0.0001) in the intra-arterial procedure group than in the intravenous group. After the exclusion of the 135 cases treated with the combination of I.V. thrombolysis and I.A. procedures, 67/189 of those treated with I.A. procedures (35.3 %) had a favourable outcome, compared to 89/324 of those treated with I.V. thrombolysis (27.4 %) (adjusted OR 1.75, 95 % CI 1.00-3.03, p = 0.05). Endovascular treatment of patients with acute ICA occlusion did not result in a better functional outcome than treatment with intravenous thrombolysis, but was associated with a higher rate of intracranial bleeding. Overall mortality was significantly reduced in patients treated with endovascular treatment but the rates of patients with severe disability or death were similar. When excluding all patients treated with the combination of I.V. thrombolysis and I.A. procedures, a potential benefit of I.A. treatment alone compared to I.V. thrombolysis was observed

European Multicenter Study of ET-COVID-19

International audienceBackground and Purpose: Acute ischemic stroke and large vessel occlusion can be concurrent with the coronavirus disease 2019 (COVID-19) infection. Outcomes after mechanical thrombectomy (MT) for large vessel occlusion in patients with COVID-19 are substantially unknown. Our aim was to study early outcomes after MT in patients with COVID-19. Methods: Multicenter, European, cohort study involving 34 stroke centers in France, Italy, Spain, and Belgium. Data were collected between March 1, 2020 and May 5, 2020. Consecutive laboratory-confirmed COVID-19 cases with large vessel occlusion, who were treated with MT, were included. Primary investigated outcome: 30-day mortality. Secondary outcomes: early neurological improvement (National Institutes of Health Stroke Scale improvement ≥8 points or 24 hours National Institutes of Health Stroke Scale 0–1), successful reperfusion (modified Thrombolysis in Cerebral Infarction grade ≥2b), and symptomatic intracranial hemorrhage. Results: We evaluated 93 patients with COVID-19 with large vessel occlusion who underwent MT (median age, 71 years [interquartile range, 59–79]; 63 men [67.7%]). Median pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT Score were 17 (interquartile range, 11–21) and 8 (interquartile range, 7–9), respectively. Anterior circulation acute ischemic stroke represented 93.5% of cases. The rate modified Thrombolysis in Cerebral Infarction 2b to 3 was 79.6% (74 patients [95% CI, 71.3–87.8]). Thirty-day mortality was 29% (27 patients [95% CI, 20–39.4]). Early neurological improvement was 19.5% (17 patients [95% CI, 11.8–29.5]), and symptomatic intracranial hemorrhage was 5.4% (5 patients [95% CI, 1.7–12.1]). Patients who died at 30 days exhibited significantly lower lymphocyte count, higher levels of aspartate, and LDH (lactate dehydrogenase). After adjustment for age, initial National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, and successful reperfusion, these biological markers remained associated with increased odds of 30-day mortality (adjusted odds ratio of 2.70 [95% CI, 1.21–5.98] per SD-log decrease in lymphocyte count, 2.66 [95% CI, 1.22–5.77] per SD-log increase in aspartate, and 4.30 [95% CI, 1.43–12.91] per SD-log increase in LDH). Conclusions: The 29% rate of 30-day mortality after MT among patients with COVID-19 is not negligible. Abnormalities of lymphocyte count, LDH and aspartate may depict a patient’s profiles with poorer outcomes after MT. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT04406090