ABSTRACT Objective To describe and compare the clinical characteristics and outcomes of patients admitted to intensive care units during the first and second waves of the COVID-19 pandemic. Methods In this retrospective single-center cohort study, data were retrieved from the Epimed Monitor System; all adult patients admitted to the intensive care unit between March 4, 2020, and October 1, 2021, were included in the study. We compared the clinical characteristics and outcomes of patients admitted to the intensive care unit of a quaternary private hospital in São Paulo, Brazil, during the first (May 1, 2020, to August 31, 2020) and second (March 1, 2021, to June 30, 2021) waves of the COVID-19 pandemic. Results In total, 1,427 patients with COVID-19 were admitted to the intensive care unit during the first (421 patients) and second (1,006 patients) waves. Compared with the first wave group [median (IQR)], the second wave group was younger [57 (46-70) versus 67 (52-80) years; p<0.001], had a lower SAPS 3 Score [45 (42-52) versus 49 (43-57); p<0.001], lower SOFA Score on intensive care unit admission [3 (1-6) versus 4 (2-6); p=0.018], lower Charlson Comorbidity Index [0 (0-1) versus 1 (0-2); p<0.001], and were less frequently frail (10.4% versus 18.1%; p<0.001). The second wave group used more noninvasive ventilation (81.3% versus 53.4%; p<0.001) and high-flow nasal cannula (63.2% versus 23.0%; p<0.001) during their intensive care unit stay. The intensive care unit (11.3% versus 10.5%; p=0.696) and in-hospital mortality (12.3% versus 12.1%; p=0.998) rates did not differ between both waves. Conclusion In the first and second waves, patients with severe COVID-19 exhibited similar mortality rates and need for invasive organ support, despite the second wave group being younger and less severely ill at the time of intensive care unit admission.

ABSTRACT Objective The incidence of thrombotic events and acute kidney injury is high in critically ill patients with COVID-19. We aimed to evaluate and compare the coagulation profiles of patients with COVID-19 developing acute kidney injury versus those who did not, during their intensive care unit stay. Methods Conventional coagulation and platelet function tests, fibrinolysis, endogenous inhibitors of coagulation tests, and rotational thromboelastometry were conducted on days 0, 1, 3, 7, and 14 following intensive care unit admission. Results Out of 30 patients included, 13 (43.4%) met the criteria for acute kidney injury. Comparing both groups, patients with acute kidney injury were older: 73 (60-84) versus 54 (47-64) years, p=0.027, and had a lower baseline glomerular filtration rate: 70 (51-81) versus 93 (83-106) mL/min/1.73m2, p=0.004. On day 1, D-dimer and fibrinogen levels were elevated but similar between groups: 1780 (1319-5517) versus 1794 (726-2324) ng/mL, p=0.145 and 608 (550-700) versus 642 (469-722) g/dL, p=0.95, respectively. Rotational thromboelastometry data were also similar between groups. However, antithrombin activity and protein C levels were lower in patients who developed acute kidney injury: 82 (75-92) versus 98 (90-116), p=0.028 and 70 (52-82) versus 88 (78-101) µ/mL, p=0.038, respectively. Mean protein C levels were lower in the group with acute kidney injury across multiple time points during their stay in the intensive care unit. Conclusion Critically ill patients experiencing acute kidney injury exhibited lower endogenous anticoagulant levels. Further studies are needed to understand the role of natural anticoagulants in the pathophysiology of acute kidney injury within this population.

Resumo Introdução: Distúrbios do metabolismo ósseo (DMO) e alterações da função vascular contribuem para a elevada mortalidade de pacientes em hemodiálise. A disfunção vascular, um novo marcador de aterosclerose, pode contribuir para este risco. Apesar de associada a aumento de mortalidade na população geral, a avaliação de tal disfunção ainda não foi realizada de modo amplo em pacientes em hemodiálise. Métodos: Neste estudo transversal, pacientes em hemodiálise foram submetidos à avaliação da vasodilatação mediada por fluxo, razão de viabilidade subendocárdica (RVSE) e índice de duração de ejeção, como estimativas de avaliação dos marcadores de DMO sobre disfunção vascular. Resultados: Uma coorte pareada com (n = 16) e sem (n = 11) hiperparatireoidismo secundário (HPTS) grave foi estudada. Adicionalmente, o tempo transcorrido do diagnóstico de HPTS grave também foi avaliado. Pacientes com HPTS grave apresentaram menores valores de RVSE e maiores valores de índice de duração de ejeção, apontando maior risco cardiovascular. Baixa RVSE também foi associada à pressão arterial diastólica (r = 0,435, p = 0,049), níveis séricos de 25-Vitamina D (r = 0,479, p = 0,028) e maior tempo transcorrido desde diagnóstico de HPTS grave, definido como tempo em que o paciente permaneceu com valores de paratormônio superiores a 500 pg/ml até realização de cirurgia de paratireoidectomia ou término do estudo (r = -0,642, p = 0,027). Em regressão logística stepwise entre RVSE e variáveis independentes, menor RVSE foi independentemente associado a menores valores de 25-Vitamina D (p = 0,005), sexo feminino (p = 0,012) e maior tempo transcorrido desde diagnóstico de HPTS grave (p = 0,001) em um modelo ajustado para idade, colesterol sérico e pressão arterial (r2 ajustado = 0,545, p = 0,001). Conclusão: A perfusão subendocárdica foi menor em pacientes com DMO, refletindo o maior risco cardiovascular nesta população. Investigações adicionais são necessárias para definir se a paratireoidectomia precoce no curso da doença renal crônica poderia interferir neste risco.

Abstract Introduction: Bone metabolism disorder (BMD) and vascular dysfunction contribute to excess cardiovascular mortality observed in hemodialysis patients. Vascular dysfunction, a new marker of atherosclerosis, can play a role in this risk. Even though associated with higher mortality in the general population, such vascular evaluation in patients on hemodialysis has not been extensively studied. Methods: In this cross-sectional study, hemodialysis patients were submitted to flow-mediated dilation, subendocardial viability ratio (SEVR) and ejection duration index assessment, in order to estimate the impact of BMD markers on vascular dysfunction. Results: A matched cohort of patients with (n = 16) and without (n = 11) severe secondary hyperparathyroidism (SHPT) was studied. Additionally, time spent under severe SHPT was also evaluated. Patients with severe SHPT had lower SEVR and higher ejection duration index, indicating higher cardiovascular risk. Lower SEVR was also associated to diastolic blood pressure (r = 0.435, p = 0.049), serum 25-Vitamin-D levels (r = 0.479, p = 0.028) and to more time spent under severe secondary hyperparathyroidism (SHPT), defined as time from PTH > 500pg/ml until parathyroidectomy surgery or end of the study (r = -0.642, p = 0.027). In stepwise multiple regression analysis between SEVR and independent variables, lower SEVR was independently associated to lower serum 25-Vitamin-D levels (p = 0.005), female sex (p = 0.012) and more time spent under severe SHPT (p = 0.001) in a model adjusted for age, serum cholesterol, and blood pressure (adjusted r² = 0.545, p = 0.001). Conclusion: Subendocardial perfusion was lower in patients with BMD, reflecting higher cardiovascular risk in this population. Whether early parathyroidectomy in the course of kidney disease could modify such results still deserves further investigation.