Learning curve of blood pressure management during pheochromocytoma surgery without preoperative alpha-blockade dose-escalation
Isabelle Holscher, Mahsoem Ali, Koen M.A. Dreijerink, Markus W. Hollmann, Tijs J. van den Berg, Wouter D. Lubbers, Els J.M. Nieveen van Dijkum, Anton F. EngelsmanAbstract
Background
Adrenalectomy without preoperative dose-escalation of α-blockade is gaining popularity for managing pheochromocytoma, showing comparable outcomes but shorter hospital stays and less postoperative hypotension. However, recent data showed an initial significant increase in intraoperative hypotension after transitioning to this approach, suggesting a learning curve. We evaluated this learning curve for safe use of our α-blockade non-escalation workflow employing a risk-adjusted CUSUM (RA-CUSUM) analysis.
Method
This single-centre cohort study included pheochromocytoma resections without preoperative α-blockade dose-escalation from 2019 until 2023. All procedures were performed by an experienced operating theatre team, including anaesthesiologists and surgeons dedicated to pheochromocytoma treatment. Intraoperative hypotension (time-weighted average [TWA] of mean arterial pressure [MAP] <60mmHg) was identified as primary learning curve outcome. RA-CUSUM analysis consisted of predicting intraoperative hypotension by a multivariable linear regression model corrected for established risk factors and modelling the relationship between number of procedures and cumulative difference in predicted and observed outcomes.
Results
A total of 44 procedures was evaluated employing the new preoperative α-blockade non-escalation strategy. RA-CUSUM analysis showed that the learning curve was completed after 19 surgeries. Median TWA of MAP < 60 mmHg was 2.29 (IQR 0.45-4.16) mmHg. No perioperative complications related to hemodynamic instability occurred in the cohort. Time in the operating theatre and length of hospital stay remained consistent over time.
Conclusion
Our results confirm that transitioning to pheochromocytoma resection without α-blockade dose-escalation follows a learning curve. To ensure safe implementation, centres adopting the non-escalation workflow should meet certain conditions, with structured guidance or proctoring as possible measures.