Impact of prone positioning on patients with COVID-19 and ARDS on invasive mechanical ventilation: a multicenter cohort study.

OBJECTIVE: To identify factors that lead to a positive oxygenation response and predictive factors of mortality after prone positioning. METHODS: This was a retrospective, multicenter, cohort study involving seven hospitals in Brazil. Inclusion criteria were being > 18 years of age with a suspected or confirmed diagnosis of COVID-19, being on invasive mechanical ventilation, having a PaO2/FIO2 ratio < 150 mmHg, and being submitted to prone positioning. After the first prone positioning session, a 20 mmHg improvement in the PaO2/FIO2 ratio was defined as a positive response. RESULTS: The study involved 574 patients, 412 (72%) of whom responded positively to the first prone positioning session. Multiple logistic regression showed that responders had lower Simplified Acute Physiology Score III (SAPS III)/SOFA scores and lower D-dimer levels (p = 0.01; p = 0.04; and p = 0.04, respectively). It was suggested that initial SAPS III and initial PaO2/FIO2 were predictors of oxygenation response. The mortality rate was 69.3%. Increased risk of mortality was associated with age (OR = 1.04 [95 CI: 1.01-1.06]), time to first prone positioning session (OR = 1.18 [95 CI: 1.06-1.31]), number of sessions (OR = 1.31 [95% CI: 1.00-1.72]), proportion of pulmonary impairment (OR = 1.55 [95% CI: 1.02-2.35]), and immunosuppression (OR = 3.83 [95% CI: 1.35-10.86]). CONCLUSIONS: Our results show that most patients in our sample had a positive oxygenation response after the first prone positioning session. However, the mortality rate was high, probably due to the health status and the number of comorbidities of the patients, as well as the severity of their disease. Our results also suggest that SAPS III and the initial PaO2/FIO2 predict the oxygenation response; in addition, age, time to first prone positioning, number of sessions, pulmonary impairment, and immunosuppression can predict mortality.

Impact of prone positioning on patients with COVID-19 and ARDS on invasive mechanical ventilation: a multicenter cohort study / Impacto da pronação em pacientes com COVID-19 e SDRA em ventilação mecânica invasiva: estudo de coorte multicêntrico

ABSTRACT Objective: To identify factors that lead to a positive oxygenation response and predictive factors of mortality after prone positioning. Methods: This was a retrospective, multicenter, cohort study involving seven hospitals in Brazil. Inclusion criteria were being > 18 years of age with a suspected or confirmed diagnosis of COVID-19, being on invasive mechanical ventilation, having a PaO2/FIO2 ratio < 150 mmHg, and being submitted to prone positioning. After the first prone positioning session, a 20 mmHg improvement in the PaO2/FIO2 ratio was defined as a positive response. Results: The study involved 574 patients, 412 (72%) of whom responded positively to the first prone positioning session. Multiple logistic regression showed that responders had lower Simplified Acute Physiology Score III (SAPS III)/SOFA scores and lower D-dimer levels (p = 0.01; p = 0.04; and p = 0.04, respectively). It was suggested that initial SAPS III and initial PaO2/FIO2 were predictors of oxygenation response. The mortality rate was 69.3%. Increased risk of mortality was associated with age (OR = 1.04 [95 CI: 1.01-1.06]), time to first prone positioning session (OR = 1.18 [95 CI: 1.06-1.31]), number of sessions (OR = 1.31 [95% CI: 1.00-1.72]), proportion of pulmonary impairment (OR = 1.55 [95% CI: 1.02-2.35]), and immunosuppression (OR = 3.83 [95% CI: 1.35-10.86]). Conclusions: Our results show that most patients in our sample had a positive oxygenation response after the first prone positioning session. However, the mortality rate was high, probably due to the health status and the number of comorbidities of the patients, as well as the severity of their disease. Our results also suggest that SAPS III and the initial PaO2/FIO2 predict the oxygenation response; in addition, age, time to first prone positioning, number of sessions, pulmonary impairment, and immunosuppression can predict mortality.

RESUMO Objetivo: Identificar fatores que levam a uma resposta positiva da oxigenação e fatores preditivos de mortalidade após a pronação. Métodos: Estudo de coorte retrospectivo multicêntrico envolvendo sete hospitais brasileiros. Os critérios de inclusão foram idade > 18 anos com diagnóstico suspeito ou confirmado de COVID-19, ventilação mecânica invasiva, relação PaO2/FIO2 < 150 mmHg e pronação. Após a primeira sessão de pronação, uma melhora de 20 mmHg na relação PaO2/FIO2 foi definida como resposta positiva. Resultados: O estudo envolveu 574 pacientes, dos quais 412 (72%) apresentaram resposta positiva à primeira sessão de pronação. A regressão logística múltipla mostrou que os respondedores apresentaram menores pontuações no Simplified Acute Physiology Score III (SAPS III) e no SOFA e menores níveis de dímero D (p = 0,01; p = 0,04; e p = 0,04, respectivamente). Sugeriu-se que a pontuação no SAPS III e a PaO2/FIO2 iniciais seriam preditores da resposta da oxigenação. A taxa de mortalidade foi de 69,3%. Maior risco de mortalidade foi associado à idade (OR = 1,04 [IC95%: 1,01-1,06]), tempo até a primeira sessão de pronação (OR = 1,18 [IC95%: 1,06-1,31]), número de sessões (OR = 1,31 [IC95%: 1,00-1,72]), porcentagem de comprometimento pulmonar (OR = 1,55 [IC95%: 1,02-2,35]) e imunossupressão (OR = 3,83 [IC95%: 1,35-10,86]). Conclusões: Nossos resultados mostram que a maioria dos pacientes de nossa amostra apresentou resposta positiva da oxigenação após a primeira sessão de pronação. No entanto, a taxa de mortalidade foi elevada, provavelmente em virtude do estado de saúde e número de comorbidades dos pacientes e da gravidade de sua doença. Nossos resultados também sugerem que a pontuação no SAPS III e a PaO2/FIO2 inicial predizem a resposta da oxigenação; além disso, idade, tempo até a primeira sessão de pronação, número de sessões, comprometimento pulmonar e imunossupressão podem predizer mortalidade.

Characteristics and outcomes of patients with COVID-19 admitted to the ICU in a university hospital in São Paulo, Brazil - study protocol

OBJECTIVES: We designed a cohort study to describe characteristics and outcomes of patients with coronavirus disease (COVID-19) admitted to the intensive care unit (ICU) in the largest public hospital in Sao Paulo, Brazil, as Latin America becomes the epicenter of the pandemic. METHODS: This is the protocol for a study being conducted at an academic hospital in Brazil with 300 adult ICU beds dedicated to COVID-19 patients. We will include adult patients admitted to the ICU with suspected or confirmed COVID-19 during the study period. The main outcome is ICU survival at 28 days. Data will be collected prospectively and retrospectively by trained investigators from the hospital's electronic medical records, using an electronic data capture tool. We will collect data on demographics, comorbidities, severity of disease, and laboratorial test results at admission. Information on the need for advanced life support and ventilator parameters will be collected during ICU stay. Patients will be followed up for 28 days in the ICU and 60 days in the hospital. We will plot Kaplan-Meier curves to estimate ICU and hospital survival and perform survival analysis using the Cox proportional hazards model to identify the main risk factors for mortality. ClinicalTrials.gov: NCT04378582. RESULTS: We expect to include a large sample of patients with COVID-19 admitted to the ICU and to be able to provide data on admission characteristics, use of advanced life support, ICU survival at 28 days, and hospital survival at 60 days. CONCLUSIONS: This study will provide epidemiological data about critically ill patients with COVID-19 in Brazil, which could inform health policy and resource allocation in low- and middle-income countries.

Optimization of conditions for apnea testing in a hypoxemic brain dead patient. / Otimização de condições para teste de apneia em paciente hipoxêmico com morte encefálica.

We report the case of a patient in whom brain death was suspected and associated with atelectasis and moderate to severe hypoxemia even though the patient was subjected to protective ventilation, a closed tracheal suction system, positive end-expiratory pressure, and recruitment maneuvers. Faced with the failure to obtain an adequate partial pressure of oxygen for the apnea test, we elected to place the patient in a prone position, use higher positive end-expiratory pressure, perform a new recruitment maneuver, and ventilate with a higher tidal volume (8mL/kg) without exceeding the plateau pressure of 30cmH2O. The apnea test was performed with the patient in a prone position, with continuous positive airway pressure coupled with a T-piece. The delay in diagnosis was 10 hours, and organ donation was not possible due to circulatory arrest. This report demonstrates the difficulties in obtaining higher levels of the partial pressure of oxygen for the apnea test. The delays in the diagnosis of brain death and in the organ donation process are discussed, as well as potential strategies to optimize the partial pressure of oxygen to perform the apnea test according to the current recommendations.

Relatamos o caso de um paciente que evoluiu com suspeita de morte encefálica associada à atelectasia e à hipoxemia moderada a grave, apesar de instituídos ventilação protetora, sistema de aspiração traqueal fechado, pressão positiva ao final da expiração moderada e manobra de recrutamento. Diante da não obtenção de pressão parcial de oxigênio adequada para o teste de apneia, optamos por pronar o paciente, utilizar pressão positiva expiratória final mais elevada, realizar nova manobra de recrutamento e ventilar com volume corrente mais elevado (8mL/kg), sem ultrapassar pressão de platô de 30cmH2O. O teste de apneia foi realizado em posição prona, com válvula de pressão positiva contínua nas vias aéreas acoplada em tubo T. O atraso no diagnóstico foi de 10 horas; a doação de órgãos não foi possível devido à parada circulatória. Este relato demonstra as dificuldades para obtenção de níveis de pressão parcial de oxigênio mais altos para a realização do teste de apneia. Os atrasos que isso pode acarretar ao diagnóstico de morte encefálica e ao processo de doação de órgãos são discutidos, além de potenciais estratégias de otimização da pressão parcial de oxigênio para realização do teste, conforme as recomendações atuais.

Otimização de condições para teste de apneia em paciente hipoxêmico com morte encefálica / Optimization of conditions for apnea testing in a hypoxemic brain dead patient

RESUMO Relatamos o caso de um paciente que evoluiu com suspeita de morte encefálica associada à atelectasia e à hipoxemia moderada a grave, apesar de instituídos ventilação protetora, sistema de aspiração traqueal fechado, pressão positiva ao final da expiração moderada e manobra de recrutamento. Diante da não obtenção de pressão parcial de oxigênio adequada para o teste de apneia, optamos por pronar o paciente, utilizar pressão positiva expiratória final mais elevada, realizar nova manobra de recrutamento e ventilar com volume corrente mais elevado (8mL/kg), sem ultrapassar pressão de platô de 30cmH2O. O teste de apneia foi realizado em posição prona, com válvula de pressão positiva contínua nas vias aéreas acoplada em tubo T. O atraso no diagnóstico foi de 10 horas; a doação de órgãos não foi possível devido à parada circulatória. Este relato demonstra as dificuldades para obtenção de níveis de pressão parcial de oxigênio mais altos para a realização do teste de apneia. Os atrasos que isso pode acarretar ao diagnóstico de morte encefálica e ao processo de doação de órgãos são discutidos, além de potenciais estratégias de otimização da pressão parcial de oxigênio para realização do teste, conforme as recomendações atuais.

ABSTRACT We report the case of a patient in whom brain death was suspected and associated with atelectasis and moderate to severe hypoxemia even though the patient was subjected to protective ventilation, a closed tracheal suction system, positive end-expiratory pressure, and recruitment maneuvers. Faced with the failure to obtain an adequate partial pressure of oxygen for the apnea test, we elected to place the patient in a prone position, use higher positive end-expiratory pressure, perform a new recruitment maneuver, and ventilate with a higher tidal volume (8mL/kg) without exceeding the plateau pressure of 30cmH2O. The apnea test was performed with the patient in a prone position, with continuous positive airway pressure coupled with a T-piece. The delay in diagnosis was 10 hours, and organ donation was not possible due to circulatory arrest. This report demonstrates the difficulties in obtaining higher levels of the partial pressure of oxygen for the apnea test. The delays in the diagnosis of brain death and in the organ donation process are discussed, as well as potential strategies to optimize the partial pressure of oxygen to perform the apnea test according to the current recommendations.