Rationalising preoperative group and save in thyroidectomy: a thyroid volume-based predictive mode

Abstract Background Routine pre-operative Group and Save (G&S) for thyroidectomy often leads to unnecessary laboratory workload and inefficient resource use. This project evaluates G&S necessity based on preoperative ultrasound, histopathology thyroid volume and intraoperative estimated blood loss (EBL) to establish a data-driven protocol. Method This quality improvement project was conducted from a retrospective chart review of all thyroidectomies performed from 2023 to date. Data included preoperative and histopathological thyroid volume, intraoperative EBL, and pre-operative G&S and cross-matching orders. Significant bleeding was defined as EBL ≥ 150 ml, as defined by current available literature. Receiver Operating Characteristic (ROC) curve analysis identified an optimal ultrasound volume threshold and histopathology volume threshold predicting EBL ≥ 150 ml. Results A total of 119 procedures were included (46 total and 73 hemithyroidectomies). Mean estimated intraoperative EBL was 108ml (median = 50 ml; range = 10–1500 ml) in total thyroidectomies and 72 ml (median = 30ml; range = 5–1000 ml) in hemithyroidectomies. Only 1 patient (0.74%) required transfusion. Preoperative ultrasound thyroid volume and histopathological thyroid volume demonstrated a strong correlation with EBL and exhibited excellent predictability for EBL ≥ 150 ml (AUC = 0.936, 95% c.i. = 0.836–1.035, P < 0.001), with an optimal cut-off at 0.61 dm3 (sensitivity = 87.5%, specificity = 97.1%). Two pre-operative G&S samples were ordered in all cases with a total estimated cost of £4760. Our optimal cut-off would have saved £4280 by requiring G&S for only 12 patients. Conclusion Transfusion during thyroid surgery is exceedingly rare, while thyroid volume strongly predicts high intraoperative blood loss. Implementing a data-driven threshold (for example volume > 0.61 dm3) may allow for more selective pre-operative G&S testing, optimizing resource use and reducing unnecessary blood orders.