Data Collection

Patients’ details such as age, gender, body mass index, degree of education and comorbidity were obtained by preoperative visit. Severity of comorbidities was calculated using the age adjusted Charlson Comorbidity Index (ACCI).¹⁴ Laboratory data, including hematocrit, white cell count, neutrophil count, lymphocyte count, platelet, and C-reactive protein (CRP) level, most recently measured preceding surgery and measured within 24h after surgery were collected. Surgery information, including operative site, operation time, anesthesia method, intraoperative medication, and hemorrhage volume, were recorded. Application of anti-inflammatory agents within 24h before surgery, during surgery and within 24h after surgery was also collected. We also collected the application of benzodiazepines and anticholinergic drugs within 48h before and after surgery. NLR was calculated as the neutrophil count divided by the lymphocyte count. PLR was calculated as the platelet count divided by the lymphocyte count, and PWR was calculated as the platelet count divided by the total white cell count.