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.

Influence of heart failure on resting lung volumes in patients with COPD / Influência da insuficiência cardíaca nos volumes pulmonares de repouso em pacientes com DPOC

ABSTRACT Objective: To evaluate the influence of chronic heart failure (CHF) on resting lung volumes in patients with COPD, i.e., inspiratory fraction-inspiratory capacity (IC)/TLC-and relative inspiratory reserve-[1 − (end-inspiratory lung volume/TLC)]. Methods: This was a prospective study involving 56 patients with COPD-24 (23 males/1 female) with COPD+CHF and 32 (28 males/4 females) with COPD only-who, after careful clinical stabilization, underwent spirometry (with forced and slow maneuvers) and whole-body plethysmography. Results: Although FEV1, as well as the FEV1/FVC and FEV1/slow vital capacity ratios, were higher in the COPD+CHF group than in the COPD group, all major "static" volumes-RV, functional residual capacity (FRC), and TLC-were lower in the former group (p < 0.05). There was a greater reduction in FRC than in RV, resulting in the expiratory reserve volume being lower in the COPD+CHF group than in the COPD group. There were relatively proportional reductions in FRC and TLC in the two groups; therefore, IC was also comparable. Consequently, the inspiratory fraction was higher in the COPD+CHF group than in the COPD group (0.42 ± 0.10 vs. 0.36 ± 0.10; p < 0.05). Although the tidal volume/IC ratio was higher in the COPD+CHF group, the relative inspiratory reserve was remarkably similar between the two groups (0.35 ± 0.09 vs. 0.44 ± 0.14; p < 0.05). Conclusions: Despite the restrictive effects of CHF, patients with COPD+CHF have relatively higher inspiratory limits (a greater inspiratory fraction). However, those patients use only a part of those limits, probably in order to avoid critical reductions in inspiratory reserve and increases in elastic recoil.

RESUMO Objetivo: Avaliar a influência da insuficiência cardíaca crônica (ICC) nos volumes pulmonares de repouso em pacientes com DPOC, ou seja, fração inspiratória -capacidade inspiratória (CI)/CPT - e reserva inspiratória relativa - [1 − (volume pulmonar inspiratório final/CPT)]. Métodos: Após cuidadosa estabilização clínica, 56 pacientes com DPOC (24 alocados no grupo DPOC+ICC; 23 homens/1 mulher) e 32 (28 homens/4 mulheres) com DPOC isolada foram submetidos à espirometria forçada e lenta e pletismografia de corpo inteiro. Resultados: Os pacientes do grupo DPOC+ICC apresentaram maior VEF1, VEF1/CVF e VEF1/capacidade vital lenta; porém, todos os principais volumes "estáticos" - VR, capacidade residual funcional (CRF) e CPT - foram menores que aqueles do grupo DPOC (p < 0,05). A CRF diminuiu mais do que o VR, determinando assim menor volume de reserva expiratória no grupo DPOC+ICC que no grupo DPOC. Houve redução relativamente proporcional da CRF e da CPT nos dois grupos; logo, a CI também foi similar. Consequentemente, a fração inspiratória no grupo DPOC+ICC foi maior que no grupo DPOC (0,42 ± 0,10 vs. 0,36 ± 0,10; p < 0,05). Embora a razão volume corrente/CI fosse maior no grupo DPOC+ICC, a reserva inspiratória relativa foi notadamente similar entre os grupos (0,35 ± 0,09 vs. 0,44 ± 0,14; p < 0,05). Conclusões: Apesar dos efeitos restritivos da ICC, pacientes com DPOC+ICC apresentam elevações relativas dos limites inspiratórios (maior fração inspiratória). Entretanto, esses pacientes utilizam apenas parte desses limites, com o provável intuito de evitar reduções críticas da reserva inspiratória e maior trabalho elástico.