These authors sought to determine the influence of preoperative anemia severity on 30-day postoperative complications following primary TSA using the National Surgical Quality Improvement Program (NSQIP) database from 2012 to 2018.
Patients undergoing TSA stratified into 3 cohorts: non-anemia (hematocrit >36% for women, > 39% for men), mild anemia (hematocrit 33% to 36% for women, 33% to 39% for men), and moderate to severe anemia (hematocrit < 33% for both women and men).
Of 13,921 total patients undergoing TSA, 11,330 patients (81.4%) did not have anemia, 1,934 (13.9%) had mild anemia, and 657 (4.7%) had moderate to severe anemia.
Patients with mild anemia were more likely to have a postoperative blood transfusion (OR 4.7; p < 0.001), extended length of stay (OR 1.7; p = 0.002), and reoperation (OR 1.5; p =0.028).
Patients with moderate to severe anemia were at increased risk of cardiac complications (OR 3.0; p = 0.012), pulmonary complications (OR 2.2; p = 0.015), postoperative blood transfusion (OR 23.8; p < 0.001), extended length of stay (OR 6.6; p < 0.001), reoperation (OR 2.2; p = 0.003), and death (OR 3.8; p = 0.034).
These findings are similar to those from another recent study.
The Impact of Preoperative Anemia on Complications After Total Shoulder Arthroplasty
These authors investigated the relationship between varying levels of preoperative anemia and postoperative complications within 30 days of total shoulder arthroplasty (TSA) in 10,547 patients.
The degree of anemia was categorized based on preoperative hematocrit levels: normal (>39% for men and >36% for women), mild anemia (29% to 39% for men and 29% to 36% for women), and severe anemia (<29% for both men and women).
1,923 patients were (18.2%) in the mild anemia cohort and 146 (1.4%) were in the severe anemia cohort.
Mild anemia was a significant predictor of any complication (odds ratio [OR] 2.74, P < 0.001), stroke/cerebrovascular accident (OR 6.79, P = 0.007), postoperative anemia requiring transfusion (OR 6.58, P < 0.001), nonhome discharge (OR 1.79, P < 0.001), readmission (OR 1.63, P < 0.001), and return to the surgical room (OR 1.60, P = 0.017).
Severe anemia was identified as a significant predictor of any complication (OR 4.31, P < 0.001), renal complication (OR 13.78, P < 0.001), postoperative anemia requiring transfusion (OR 5.62, P < 0.001), and nonhome discharge (OR 2.34, P < 0.001).
Comment: These authors found that 20% of patients having TSA were anemic! Preoperative anemia status was a notable risk factor for postoperative complications within 30 days of TSA. Even mildly decreased preoperative hematocrit levels (between 29% and 36% for women and between 29% and 39% for men) notably increased the risk of stroke/CVA, postoperative anemia requiring transfusion, nonhome discharge, hospital readmission, and return to the surgical room. In addition, severe anemia (hematocrit <29% in both men and women) was identified as a predictor of postoperative anemia requiring transfusion, nonhome discharge, and renal complications after TSA.
A greater proportion of patients with mild anemia were functionally dependent, used steroids, had an ASA ≥3, and had a BMI <25.
Anemia may result from nutrient deficiency, chronic proinflammatory states, chronic kidney disease, and bone marrow dysfunction. Deficiencies of vitamin B12, iron, and folate may account for one third of the etiologies of anemia.
These studies did not evaluate the effectiveness of correcting patients' hematocrit preoperatively on postoperative complications after TSA.
