Exploring Military Logistics and Storage Systems to Decrease the Rate of Failed Bupivacaine Spinals for Cesarean...

Neuraxial anesthesia with hyperbaric bupivacaine is the gold standard anesthetic for cesarean delivery (CD), yet bupivacaine spinal failure rates have been reported as high as 25.3% and often occur in unexplained clusters. Our military treatment facility (MTF) has informally tracked batch-associated failures since 2019, but established a formal tracking system in 2024. This project aimed to identify supply-chain and storage factors contributing to bupivacaine failures, reduce the overall failure rate to <4%, and reduce general anesthetics (GA) attributed to failed spinals to zero percent within 3 years.

This quality improvement project was given research-exempt status by the Brooke Army Medical Center Human Research Protections Office, reference number 996159. Using sequential Plan-Do-Study-Act cycles, we established a departmental failure-reporting system, provided departmental education on the risks of failure, replaced any bupivacaine lot after two failures, changed manufacturers, and reviewed transport and storage with Logistics and the Defense Health Agency's Medical Material Quality Control system. Pyxis and operating room temperatures were measured directly. After the 12th failure, bupivacaine vials were relocated from the pyxis to a room temperature wall-unit lock box.

From January 2024 to June 2026, 19 failures occurred among an estimated 960 vials, for an overall failure rate of 2.0%. Bupivacaine stored in the pyxis or spinal kits failed at a rate of 3.9% (13/336, 95% CI, 2.3-6.5) versus 1.0% (6/624, 95% CI, 0.4-2.1) when stored in a room temperature lock box. Annual failure rates fell from 3.6% in 2024 (10/274, 95% CI, 2-6.6) to 0.9% in 2026 (2/230, 95% CI, 0.2-3.1). GAs attributed to a failed spinal dropped from 37.5% in 2024 (6/16, 95% CI, 18.5-61.4) to 0.0% in 2026 (0/23, 95% CI, 0-14.3). The most significant drop in GA rates attributed to failed spinal occurred after relocating the bupivacaine vials from the pyxis to the wall unit lock box: 19.4% (6/31, 95% CI, 9.2-36.3) to 2.5% (1/40, 95% CI, 0.4-12.9). The temperature log revealed the rear pyxis pocket averaged 76.0°F but exceeded the maximum recommended storage temperature of 77.0°F on 13 occasions.

Controlled, monitored bupivacaine storage paired with a simple reporting pathway to identify cluster failures was associated with a clinically meaningful reduction in spinal failures and failed-spinal GAs for CD. The intervention is low-cost, sustainable, and has external validity for all MTFs storing bupivacaine. It is relevant to deployed settings where temperature control is challenging, and where spinal anesthetics offer superior anesthesia with minimal resources. Limitations include concurrent interventions, annual bupivacaine use for determining failure rates was estimated, and few events occurred. Future work could add continuous temperature logging and multi-site collaboration.