Natural outcome of hemoglobin and hematocrit in elderly patients without allogeneic blood transfusion after total knee and hip arthroplasty

Abstract

Objective To explore the natural outcome of perioperative hemoglobin and hematocrit of undergoing TKA or THA without blood transfusion and evaluate the influence of gender and type of arthroplasty on it. Methods This is a cohort study on 107 patients with osteoarthritis and more than 60 years of age receiving TKA or THA without allogeneic blood transfusion from September 2012 to February 2013. There were 54 males and 53 females with a mean age of 69.4 years (range: 60-82). Levels of hemoglobin and hematocrit were examined preoperatively immediately after surgery and on postoperative day 1-7 during hospitalization. After being discharged from the hospital, patients were followed up by clinic visit at the 3rd week, the 6th week, the 3rd month and the 6th month after surgery. Blood test was performed to examine the levels of hemoglobin and hematocrit. Based on gender and type of arthroplasty, the levels of hemoglobin and hematocrit at every time point were compared with each ether. The influence of gender and type of arthroplasty on levels of hemoglobin and hematocrit was further evaluated. Results Levels of hemoglobin and hematocrit of all patients significantly decreased postoperatively and reached the minimum values on postoperative day 4. From postoperative week 1 to 3, levels of hemoglobin and hematocrit rebounded the fastest. Levels of hemoglobin and hematocrit rebounded to their preoperative levels within postoperative 6-12 weeks. No significant difference in levels of hemoglobin and hematocrit was found between groups with different genders. Patients undergoing THA had significantly greater drop in the level of hemoglobin than those undergoing TKA in the first 4 days postoperatively (P<0.05). Patients undergoing THA had significantly greater drop in the level of hematocrit than those undergoing TKA in the operation day (P<0.05). No significant difference was found at other time points between patients receiving THA and TKA. Conclusion Levels of hemoglobin and hematocrit decreased during the first 4 days after arthroplasty and gradually returned to normal values within postoperative 6-12 weeks. Gender had no influence on the natural outcome of perioperative hemoglobin and hematocrit. Patients undergoing THA had more postoperative blood loss than those undergoing TKA. Key words: Aged; Erythrocyte indices; Arthroplasty, replacement, hip; Arthroplasty, replacement, knee