{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T23:09:10Z","timestamp":1784070550837,"version":"3.55.0"},"reference-count":28,"publisher":"Georg Thieme Verlag KG","issue":"06","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"content-version":"vor","delay-in-days":43,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Arq Neuropsiquiatr"],"published-print":{"date-parts":[[2026,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Transcranial Doppler (TCD) is a diagnostic tool to detect real-time spontaneous microembolic signals (MESs) in intracranial circulation. Critically-ill coronavirus disease 2019 (COVID-19) patients may present an increased likelihood of MESs due to systemic inflammation and hypercoagulability.<\/jats:p>\n                  <jats:p>To assess the presence of MESs and other TCD parameters, including cerebral blood flow velocity (CBFV), pulsatility, and resistance indices, and to calculate the estimated cerebral perfusion pressure (eCPP) in patients with and without COVID-19.<\/jats:p>\n                  <jats:p>The TCD monitoring was performed for 1\u2009hour in both middle cerebral arteries (MCAs) of adult patients in the Intensive Care Unit (ICU) with confirmed COVID-19 infection. The eCPP was calculated by multiplying the mean arterial pressure (MAP) by the ratio of end-diastolic velocity to mean CBFV, then adding 14\u2009mmHg.<\/jats:p>\n                  <jats:p>We evaluated 31 subjects: 11 intubated COVID-19 patients, 10 non-intubated COVID-19 patients, and 10 intubated non-COVID-19 patients. Patient ages ranged from 29 to 84 (median: 62; interquartile range [IQR]: 50\u201370) years, with 64.5% being male individuals. A total of 17 (54.8%) subjects died during hospitalization, and 2 patients (6.45%) lacked an ultrasonographic signal via the transtemporal window. No MESs were detected. A positive correlation was found between the resistance index of MCAs (p\u2009=\u20090.390) and D-dimer (p\u2009=\u20090.049). In contrast, direct bilirubin (p\u2009=\u2009-0.494), C-reactive protein (CRP; p\u2009=\u2009-0.540), activated partial thromboplastin time (aPTT; p\u2009=\u2009-0.495), and D-dimer (p\u2009=\u2009-0.439) were negatively correlated with eCPP.<\/jats:p>\n                  <jats:p>No spontaneous cerebral microemboli were observed in this cohort, but patients with higher direct bilirubin, CRP, aPTT, and D-dimer presented lower eCPP.<\/jats:p>","DOI":"10.1055\/s-0046-1825526","type":"journal-article","created":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T22:58:40Z","timestamp":1784069920000},"page":"001-009","source":"Crossref","is-referenced-by-count":0,"title":["Transcranial Doppler findings in patients with COVID-19: a prospective observational study"],"prefix":"10.1055","volume":"84","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1072-1536","authenticated-orcid":false,"given":"Marcella Barreto","family":"Santos","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3539-9579","authenticated-orcid":false,"given":"Ana Fl\u00e1via","family":"Silveira","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Carlos, Centro de Ci\u00eancias Biol\u00f3gicas e da Sa\u00fade, Departamento de Fisioterapia, S\u00e3o Carlos SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8768-7164","authenticated-orcid":false,"given":"Jo\u00e3o Brainer Clares de","family":"Andrade","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."},{"name":"Centro Universit\u00e1rio S\u00e3o Camilo, S\u00e3o Paulo SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0981-3919","authenticated-orcid":false,"given":"Eva Carolina","family":"Rocha","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4838-2840","authenticated-orcid":false,"given":"Fabiano Moulin de","family":"Moraes","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7586-1524","authenticated-orcid":false,"given":"Hanna Nery Ferraz","family":"Martins","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2976-6782","authenticated-orcid":false,"given":"Daniela Laranja Gomes","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."},{"name":"Hospital Alem\u00e3o Oswaldo Cruz, Responsabilidade Social, S\u00e3o Paulo, Brazil."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3247-3123","authenticated-orcid":false,"given":"Gisele Sampaio","family":"Silva","sequence":"additional","affiliation":[{"name":"Universidade Federal de S\u00e3o Paulo, Escola Paulista de Medicina, Departamento de Neurologia e Neurocirurgia, S\u00e3o Paulo SP, Brazil."},{"name":"Hospital Israelita Albert Einstein, 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