Clinical Characteristics Associated With COVID-19 In Severe And Critical Patients

Objective: Due to the small proportion of severe and critical COVID-19 patients,little is known about their clinical characteristics.Therefore,this study intends to analyze the clinical characteristics of severe and critical COVID-19 patients as well as survivor and non-survivor in critical cases.Methods: Retrospective study was used to assess factors associated with severity and death of COVID-19 patients.Data collected from electronic medical records of COVID-19 patients admitted to The General Hospital of Central Theater Command and Maternal and Maternal and Child Health Hospital of Hubei Province from December 2019 to March 2020.Clinical characteristics of severe and critical patients were described in this study,and statistical analysis was used to compare the clinical characteristics of the two types of patients to explore the risk factors related to disease progression and death of COVID-19 patients.Results: First of all,a total of 144 severe and critical COVID-19 patients were included in this study.Median age was 71 years(IQR,57-81 years),and96/144(66.7%)patients were males.The clinical symptoms included fever(103/144,71.5%),cough(82/144,56.9%),dyspnea(63/144,43.8%),fatigue(48/144,33.3%),chest tightness(34/144,23.6%),gastrointestinal symptoms(18/144,12.5%),myalgia(11/144,7.6%),headache(4/144,2.8%)and dizziness(2/144,1.4%).The overall mortality rate was 20.8%.Comparison of clinical features between severe and critical COVID-19 patients: 95/144(66.0%)patients were severe COVID-19 patients.Median age was 68 years(IQR,57-79years),and 64/95(67.4%)patients were males.The mortality rate was 1.1%.49/144(34.0%)patients were critical COVID-19 patients.Median age was 74years(IQR,65-85 years),and 32/49(65.3%)patients were males.The mortality rate was 59.2%.Univariate analysis show that critically ill COVID-19 patients more likely to have multiple complications,higher White blood cell count,higher neutrophil count,higher C-reactive protein(CRP)levels,higher procalcitonin(PCT)levels,higher interleukin-6(IL-6)levels,higher total bilirubin levels,higher alanine aminotransferase(ALT)levels,higher aspartate aminotransferase(AST)levels,higher creatinine levels,lower lymphocyte count,lower platelet count,lower hemoglobin levels and lower albumin levels than patients with severe COVID-19.Multivariate logistic regression analyses showed that critically ill COVID-19 patients more likely to have lower lymphocyte count(OR 4.420,95%CI 1.326-14.733;P=0.016),higher PCT levels(OR 2.008,95%CI 1.225-3.294;P=0.006),higher IL-6 levels(OR 1.813,95%CI 1.106-2.971;P=0.018)and higher creatinine levels(OR=207.285,95%CI 8.438-5091.975;P=0.001)than severe COVID-19 patients.Second,comparison of clinical features between survivor and non-survivor in critical COVID-19 patients: Univariate analysis show that non-survivor in critically ill COVID-19 patients was more likely to be older age(OR 1.053,95%CI 1.004-1.104;P=0.033),multiple complications,higher CRP levels,higher PCT levels and lower PH levels than survivor.Multivariate logistic regression analyses showed that multiple complications(OR 4.008,95%CI1.432-11.222;P=0.008)was independent predictor of mortality in critically ill COVID-19 patients compared to survivor.The last,analysis on the variation trend of laboratory indicators of survivor and non-survivor in critical COVID-19 patients: Lymphocyte count was decreased in both survivor and non-survivor critically ill patients,but the rate and degree of decrease in death patients was more significant than that in survivor,and there were two drops.The D-dimer of survivor was less than 1000.0 ng/ml during the disease period,while the D-dimer of death patients increased significantly 10 days after the disease onset,suggesting that D-dimer may be related to the death of critical patients.The time of its significant increase coincided with the time when the lymphocyte count was at its lowest.The increase of troponin T in the 3rd week of the disease onset among non-survivor critical patients,earlier than that of NT-Pro BNP(the increase after the 5th week of the disease onset).Abnormality of these two indicators may be related to the change of condition and death in the 3rd to 5th week of disease onset in critical COVID-19 patients.IL-6 and PCT increased rapidly after 6 weeks in non-survivor critically ill patients,suggesting that it was related to bacterial infection.Conclusion: Critically ill COVID-19 patients more likely to have excessive inflammatory response,immunosuppression,organ dysfunction,combined bacterial infection or secondary bacterial infection than patients with severe COVID-19.Critical COVID-19 patients with multiple complications more likely to be worse outcome,the elevated of D-dimer,troponin T,NT-pro BNP,IL-6 and PCT are associated with complications.