Prognostic value of hemoglobin-to-red cell distribution width ratio in patients with cardiopulmonary resuscitation after out-of-hospital cardiac arrest

Abstract

To investigate the prognostic value of hemoglobin-to-red cell distribution width ratio (HRR) in patients with cardiopulmonary resuscitation (CPR) after out-of-hospital cardiac arrest (OHCA). A retrospective study was conducted. Patients aged ≥ 18 years with OHCA who were transferred to intensive care unit (ICU) after successful CPR from the emergency room of the First Affiliated Hospital of Zhengzhou University from August 2016 to February 2022 were enrolled. General clinical data, initial vital signs, acute physiology and chronic health evaluation II (APACHE II), Glasgow coma scale (GCS), first laboratory indicators after admission to ICU [including white blood cell count (WBC), red blood cell count (RBC), hemoglobin (Hb), pH value, lactic acid (Lac), 6-hour lactic acid clearance (LCR), red cell distribution width (RDW), HRR], length of ICU stay were collected. According to whether the patients died in hospital, the patients were divided into survival group and death group. Binary Logistic regression was used to analyze the independent factors influencing the prognosis of patients after CPR. Receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of independent influencing factors for the prognosis of patients after CPR. A total of 122 patients were enrolled after OHCA CPR, of which 88 died in hospital, the in-hospital mortality was 72.13%. There were no significant differences in age, past medical history, initial vital signs and WBC in ICU between the two groups. Compared with the death group, the survival group had higher GCS score, RBC, Hb, pH value, 6-hour LCR, HRR, lower APACHE II score, Lac, RDW level, and longer length of ICU stay. Multivariate Logistic regression analysis showed that APACHE II score, GCS score, 6-hour LCR, HRR, length of ICU stay were independent factors influencing the prognosis of patients after CPR [APACHE II score: odds ratio (OR) = 0.784, 95% confidence interval (95%CI) was 0.683-0.901, P = 0.001; GCS score: OR = 1.390, 95%CI was 1.059-1.823, P = 0.018; 6-hour LCR: OR = 1.039, 95%CI was 1.015-1.064, P = 0.001; HRR: OR = 2.047, 95%CI was 1.383-3.029, P < 0.001; length of ICU stay: OR = 1.128, 95%CI was 1.046-1.216, P = 0.002]. ROC curve analysis showed that HRR, 6-hour LCR and APACHE II score could predict the prognosis of patients after CPR. The sensitivity was 85.3% and the specificity was 54.5% when the area under the ROC curve (AUC) of HRR was 0.731, and the cut-off value was 8.555. The sensitivity was 88.2% and the specificity was 46.6%, when the AUC of 6-hour LCR was 0.701, and the cut-off value was 28.947%. The sensitivity was 73.9% and the specificity was 79.4% when the AUC of APACHE II score was 0.848, the cut-off value was 22.000. The predictive value of the combination of HRR and 6-hour LCR was higher than that of a single index. The sensitivity was 79.3% and the specificity was 76.1%, when the AUC was 0.796, the cut-off value was 0.296. HRR, 6-hour LCR and APACHE II score have high prognostic value in patients with OHCA after CPR. HRR < 8.555, 6-hour LCR < 28.947% and APACHE II score > 22.000 indicated poor prognosis.