This comparative study enrolled patients with DQ poisoning treated in the Emergency Department of Fu Yang People’s Hospital between January 2018 and February 2022. The inclusion criteria were as follows: (1) patients with DQ poisoning; (2) complete clinical data including patient's clinical characteristics and biochemical indicators. The exclusion criteria were: (1) history of systemic rheumatic diseases; (2) previous history of one or more chronic organ dysfunction; (3) immune disorders.

This study was approved by the Ethics Committee of Fu Yang People’s Hospital. The committee waived the requirement for informed consent due to the nature of the retrospective study.

The following clinical characteristics of the patients were collected, including gender, age, occupation (Table 1), underlying disease, alcohol consumption; time interval from poisoning to hospital admission, type and dose of poisoning, vital signs on admission, gastric lavage, catharsis, enema, blood transfusion, time from poisoning to treatment; the renal, hepatic, myocardial and pulmonary function, coagulation function; Glasgow Coma Scale (GCS), systemic inflammatory response syndrome (SIRS) score, acute physiology and chronic health evaluation-II (APACHE-II) score. Biochemical indicators [white blood cell (WBC), hematocrit (HCT), prothrombin time (PT), thrombin time (TT), D-dimer (D-D), glucose (GLU), lactate dehydrogenase (LDH), creatine kinase (CK), kinase-MB isoform (CK-MB), kalium (K), sodium (NA), CO2/(HCO3), blood urea nitrogen (BUN), creatinine (CREA), and C-reactive protein (CRP)] were collected immediately at the time of admission, the highest value (WBC, PT, TT, D-D, GLU, LDH, CK, CK-MB, K, NA, CO2/(HCO3), BUN, CREA, and CRP) and lowest value (HCT, PT, TT, GLU, K, NA, and CO2/(HCO3)) were collected after admission. Time at admission refers to the value of the first measurement within 2 h after admission; lowest value after admission refers to the lowest measurement during the treatment processes after admission; highest value after admission refers to the highest measurement during the treatment processes.

Acute DQ poisoning refers to cases with one overdose or high dose exposure of DQ that induced diseases or death due to structural and functional damages to tissues or metabolic disorders. Respiratory failure refers to the severe pulmonary ventilation and/or respiratory dysfunctions caused by various causes, leading to the incapability of effective gas exchange, hypoxia accompanied with (or without) CO2 retention, and consequently causing acute respiratory distress clinical syndrome and metabolic disturbance. Organ damage refers to visceral function abnormalities, such as renal, hepatic, pulmonary or cardiac dysfunction. The time interval from poisoning to treatment refers to the time from oral intake of DQ to being treated in the Emergency Department of Fu Yang People’s Hospital.

GCS score can be used to judge and assess the degree of coma in the patients and help make an appropriate diagnosis and treatment [14]. The GCS includes three aspects: eye-opening, verbal, and motor response. The summary of scores of the 3 aspects is the coma index, an indicator for evaluating the degree of coma in patients in clinical practices. SIRS score reflects the pathophysiological status induced by the over-secretion of various inflammatory mediators and the over-activation of inflammatory cells after exposure to infectious or non-infectious agents [15]. The SIRS score is used to assess the disease condition in the post-operative care of critical patients who underwent surgery. The APACHE-II is a severity-of-disease scoring system [16] that consists of 3 parts: acute physiology, age, and chronic health conditions. The total score of APACHE-II is calculated by adding the scores from the 3 parts. MOF is defined as the failure of ≥ 3 organs.

Patients were categorized into survivor and non-survivor groups according to the final outcomes. Patients who died during hospitalization or within 2 months after discharge were classified as the non-survivor group. Death was diagnosed according to cardiac and respiratory arrest markers and brain death.

IBM SPSS Statistics, version 22.0 (IBM Corp., Armonk, N.Y., USA) was used for statistical analyses. Continuous data with normal distribution and equal variances were described by mean and standard deviation (SD). An independent t-test was used for group comparison. Continuous data with skewed distribution were described by median (interquartile range: P25, P75), and group comparison was performed with a non-parametric rank-sum test. Categorical data were described by percentages (%) and compared using the chi-square test. Multivariate logistic regression analysis was performed to explore the independent risk factors of the death. A two-sided P < 0.05 was considered statistically significant.