ABSTRACT
Objective To investigate the predictive value of central venous-to-arterial carbon dioxide difference (Pcv-aCO2) on the prognosis of elderly patients with sepsis.Methods 208 elderly patients who met the diagnostic criteria of the Sepsis-3 and with the age of more than 60 years old, and admitted to intensive care unit (ICU) of Guangdong General Hospital from January to December in 2017 were enrolled. According to the prognosis, the patients were divided into death group (n = 46) and survival group (n = 162). The Pcv-aCO2, central venous oxygen saturation (ScvO2), serum procalcitonin (PCT), C-reactive protein (CRP), sequential organ failure assessment (SOFA) and acute physiology and chronic health evaluationⅡ (APACHEⅡ) were collected for all patients. The differences of each index between the two groups were compared. The correlations between Pcv-aCO2 and ScvO2, PCT, CRP, SOFA, APACHEⅡscores were analyzed respectively with Pearson correlation. The prognostic value of Pcv-aCO2 in elderly patients with sepsis was assessed by receiver operating characteristic curve (ROC).Results Compared with survival group, the Pcv-aCO2, PCT, CRP, SOFA and APACHEⅡscores in death group were significantly increased [Pcv-aCO2 (mmHg, 1 mmHg = 0.133 kPa): 6.13±3.33 vs. 4.40±2.65, PCT (μg/L): 31.41±12.83 vs. 3.01±2.69, CRP (mg/L): 130.51± 42.23 vs. 104.46±50.12, SOFA: 12.01±2.25 vs. 9.05±2.06, APACHEⅡ: 29.52±5.03 vs. 20.01±3.21, allP < 0.05], and ScvO2 in death group was significantly decreased (0.571±0.136 vs. 0.685±0.106,P < 0.01). Correlation analysis showed that the Pcv-aCO2 was negatively correlated with ScvO2 (r = -0.762,P = 0.001) and was positively correlated with PCT, CRP, SOFA and APACHEⅡscores (r value was 0.737, 0.625, 0.738, 0.713, respectively, allP < 0.05). ROC curve analysis showed that the area under the ROC curve (AUC) of Pcv-aCO2 prediction of death in patients with sepsis was 0.826, the cut-off was 6.62 mmHg, the sensitivity was 84.7％, the specificity was 77.5％, the positive likelihood ratio was 3.76, and the negative likelihood ratio was 0.19.Conclusion Pcv-aCO2 has a great value in evaluating the prognosis of elderly patients with sepsis and can accurately determine the prognosis of sepsis.