Development of a risk prediction model for transfusion in carotid endarterectomy and demonstration of cost-saving potential by avoidance of “type and screen”

Abstract

Objectives Preoperative testing for carotid endarterectomy (CEA) often includes blood typing and antibody screen (T&S). In our institutional experience, however, transfusion for CEA is rare. We assessed transfusion rate and risk factors in a national clinical database to identify a cohort of patients in whom T&S can safely be avoided with the potential for substantial cost savings. Methods Using the NSQIP database, transfusion events and timing were established for all elective CEAs in 2012–13. Comorbidities and other characteristics were compared for patients receiving intra- or postoperative transfusion and those that did not. After random assignment of the total data to either a training or validation set, a prediction model for transfusion risk was created and subsequently validated. Results Of 16,043 patients undergoing CEA in 2012–13, 276 received at least one transfusion prior to discharge (1.7%). 42% of transfusions occurred on the day of surgery. Preoperative hematocrit < 30% (Odds ration OR: 57.4; 95% confidence interval CI: 29.6–111.1), history of congestive heart failure (OR: 2.8; 95%CI: 1.1 – 7.1), dependent functional status (OR: 2.7; 95%CI: 1.5–5.1), coagulopathy (OR: 2.5; 95%CI: 1.7–3.6), creatinine ≥ 1.2 mg/dl (OR: 2.3; 95%CI: 1.6–3.3) preoperative dyspnea (OR: 2.0; 95%CI: 1.4–3.1) and female gender (OR: 1.6; 95%CI: 1.1–2.3) predicted transfusion. A risk prediction model based on these data produced a C-statistic of 0.85; application of this model to the validation set demonstrated a C-statistic of 0.81. 93% of patients in the validation set received a score of 6 or less corresponding to an individual predicted transfusion risk of 5% or less. Omitting a T&S in these patients would generate a substantial annual cost saving for NSQIP hospitals. Conclusions While T&S is commonly performed for patients undergoing CEA, transfusion following CEA is rare and well predicted by a transfusion risk score. Avoidance of T&S in this low-risk population provides a substantial cost-saving opportunity without compromise of patient care.

Cost-Effectiveness of Routine Type and Screens in Select Endonasal Skull Base Surgeries

“…population, amounting to potential savings of more than $5.2M. 23 This 5% transfusion threshold is widely supported in the literature. 1,25,26,37 We too identified a similar threshold using one-way sensitivity analysis, which demonstrated that the risk of transfusion should exceed 4.12% to justify preoperative T/S.…”

“…[33][34][35][36] The additional risk factors identified in this analysis, such as liver disease and widespread cancer, can be used to develop a transfusion prediction model, similar to the case for carotid endarterectomy. 23 Using a 5% predicted transfusion risk threshold, the referenced authors concluded that a preoperative T/S can safely be avoided in 93% of their studied Fig. 2 One-way sensitivity analysis of variability in rate of transfusion.…”

A preoperative risk score for transfusion in infrarenal endovascular aneurysm repair to avoid type and cross

“…We chose a threshold of 5% based on prior work related to avoiding type and screen in patients undergoing carotid endarterectomy. 30 This threshold is likely overly conservative, and can be modified depending on the characteristics of the individual centers. For example, centers with robust, well-developed massive transfusion protocols and electronic type and cross can apply higher thresholds, whereas centers without those capabilities can use a lower score.…”

Development of a preoperative risk score predicting allogeneic red blood cell transfusion in children undergoing spinal fusion

“…While numerous studies associate bleeding and transfusion with several perioperative and surgical factors, source data are often based on a single‐center experience, are missing key covariate data, and yield inconsistent results 5,6,11–16 . Although transfusion prediction models have been developed for several surgical procedures, such as head and neck cancer surgery, coronary artery bypass graft surgery, total joint arthroplasty, and carotid endarterectomy, these models are often limited primarily to adult patients 17–20 . The categorization of transfusion risk based on characteristics known preoperatively is in its early stages in pediatric surgical patients, and the current literature encourages more investigation to enable reliable risk stratification and to enhance preoperative planning in this population 6,21 …”