Factors associated with increased mortality in critically ill COVID-19 patients in a Mexican public hospital: the other faces of health system oversaturation.

BACKGROUNDThe lethality rate of COVID-19 in Mexico is one of the highest worldwide, but in-hospital factors associated with this increased rate have yet to be explored. This study aims to evaluate those factors that could be associated with mortality at 28-days in critically ill COVID-19 patients in Mexico. METHODSThis is a retrospective analysis of the patients included in the clinical trial (NCT04381858) which recruited patients with severe COVID-19 with high oxygen requirement or mechanical ventilation from May to October 2020. The primary outcome, death at 28, was analyzed. RESULTSBetween May and October 2020, 196 predominantly male patients (n=122, 62.2%) with an average of 58.1 years ({+/-} 15.5), were included in the cohort. Mortality at 28 days was 44.3 % (n= 84). Patients included in the second trimester had a greater mortality rate when compared with those recruited in the first trimester (54.1 vs 32.1, p< 0.01). On multivariate analysis, the detected protective factors were the use of fentanyl HR 0.51 (95%CI 0.31 - 0.85, p=0.01), the use of antibiotics HR 0.22 (95% CI 0.13 - 0.36, p<0.01), and a previously healthy state (no comorbidities other than obesity) HR 0.58 (95%CI 0.35 - 0.94, p =0.03); risk factors were severe kidney injury (AKIN3) HR 1.74 (95%CI 1.04 - 2.9, p=0.035), elevated D-Dimer levels HR 1.02 (95%CI 1.007 - 1.04, p=0.005), shock OR 5.8 (2.4 - 13.8, p<0.01), and recruitment in the second trimester OR 2.3 ((1.1 - 4.8, p=0.02). CONCLUSIONSIn-hospital mortality in critically ill COVID-19 patients has increased in our center. The appropriate use of antibiotics, the type of sedation, and AKIN3 are modifiable factors directly related to this increased mortality. The increase in mortality observed in the second trimester is explained by hospital overcrowding that began in August 2020.