[Association studies between postoperative hypoeosinophilia and hospital stay in patients undergoing hip fracture surgery under different anesthesia].

To investigate early postoperative changes in eosinophils (EOS) and the relationship of postoperative hospital stay and hypoeosinophilia in patients undergoing hip fracture surgery under general or spinal anesthesia. The clinical data of patients who underwent hip fracture surgery at Beijing Tiantan Hospital between April 2014 and November 2017 were retrospectively analyzed. Patients were classified according to whether they received general anesthesia or spinal anesthesia. Univariate regression analysis was used to examine a number of covariates potentially contributed to postoperative hospital stay. Multivariate linear regression was used to analyze the relationship between postoperative day 1 EOS counts and postoperative hospital stay. Interaction and stratified analyses were conducted according to anesthesia methods. A total of 149 patients were included in this study. Thirty-four of them underwent general anesthesia and 115 of them underwent spinal anesthesia. The postoperative day 1 EOS of the general anesthesia group was 0 (0,1.8)×10/L, which was lower than that of the spinal anesthesia group 1.0(0,6.0)×10/L (=3.095, <0.01). After adjusting the confounders of age, gender, American Society of Anesthesiologists (ASA) grade, intraoperative blood loss, intraoperative red blood cell (RBC) transfusion, postoperative day 1 hematocrit (HCT) and white blood cell (WBC), postoperative complications, and the interaction terms for ASA, intraoperative blood loss, intraoperative RBC transfusion and postoperative complications, the negative correlation between postoperative hospital stay and postoperative day 1 EOS level was significant (β=-0.39, 95%:-0.74--0.05, <0.05) in the general anesthesia group. EOS were significantly decreased after surgery in general anesthesia group, and the postoperative hospital stay was negatively correlated with postoperative day 1 hypoeosinophilia.