Drivers of Intraoperative Costs for Transsphenoidal Endoscopic Surgery for Sellar Lesions: A Time-Driven Activity-Based Cost Analysis

Neurosurgeons lack precise insights into the true costs of transsphenoidal endoscopic surgery for sellar and suprasellar lesions (TESS), including pituitary adenomas, craniopharyngiomas, and apoplexy. To address this critical knowledge gap, we employ time-driven activity-based costing (TDABC) for TESS. We analyzed 221 TESS procedures performed between 2017 and 2022 at a large academic medical center. Costs were calculated using TDABC. Software was developed to extract information regarding all resources utilized intraoperatively. Supply cost was calculated as the aggregate of expenses related to implants, consumables, medications, and surgical tray sterilization. Personnel cost was determined by multiplying the per-minute wages of all intraoperative personnel by the amount of time they spent in the operating room (OR). Patient and disease-specific variables were collected. Multivariable regression models were performed to assess predictors of cost. The average total cost of a TESS procedure was $7,557 +/- $2,365, with primary cost drivers being supplies ($2,811, 37%) and personnel ($4,426, 59%). On multivariable regression, factors independently associated with higher total cost were hospital site (β-coefficient: $1,028, p<0.001), intraoperative blood loss (β-coefficient: $12, p<0.001), length of stay (β-coefficient: $23, p=0.015) and the use of a nasoseptal flap (β-coefficient: $731, p=0.012). Conversely, apoplexy was associated with lower total cost (β-coefficient: $-1,149, p=0.001), which was explained by faster OR times and lower personnel cost (β-coefficient: $-702, p=0.003). This study represents the first application of intra-operative TDABC for transsphenoidal endoscopic surgery. Such efforts can promote value-based healthcare by identifying areas for cost reduction and surgical resource management.