Maung et al’s ‘Door to Needle Time: Has the 2022 ACS VRC Interventional Radiology Readiness Standard Made a Difference?’ raises an equally important question as the one it attempts to answer: does ‘door-to-needle time’ in trauma patients, analogous to ‘door-to-balloon’ time in myocardial infarction (MI), have equivalent clinical utility?1
It is almost unfair to compare the two. In MI, and similarly in large vessel occlusion stroke, the pathology is most often a single, well-defined vascular occlusion, and the intervention directly addresses the sole problem. The time sensitivity in MI and stroke is driven by progressive, irreversible tissue loss, and in both, diagnostic certainty is usually high, which facilitates patient transport to the catheterization laboratory or angio-suite as the primary destination after the initial diagnosis is made. This creates a linear relationship between a uniform pathology and a singular type of intervention.
In contrast, trauma hemorrhage is a systems/multisystem problem, complicated by heterogeneous pathology, which requires a multidisciplinary response to injuries that are variable in number, location, severity, and hemodynamic impact. The heterogeneity opens multiple management pathways and makes it difficult to isolate the independent effect of ‘door-to-needle time’, as this interval is confounded by the complexity of workup and competing interventions. The pathophysiology is fundamentally different: in trauma, volume depletion and oxygen debt, not end-organ ischemia from fixed occlusion, are the foci of management, and hemorrhage can at least be partially mitigated by resuscitation while awaiting definitive hemostasis.
When evaluating how trauma centers are adapting to new mandates, we must also recognize that relying on registry data to measure granular operational efficiency introduces several methodological blind spots. Evaluating the 2022 ACS VRC mandate through the TQP-PUF database is a commendable undertaking, but the analysis is limited by the reality of how interventional radiology (IR) is operationalized.
The most glaring limitation—which the authors acknowledge but perhaps understate—is the mismatch between what the ACS standard requires and what the database actually measures. The ACS VRC standard mandates 60 min from the time of request. The TQP-PUF database, however, only records the time from ED arrival to needle puncture. From an IR operational perspective, the ‘decision-to-puncture’ interval is entirely different from the ‘door-to-puncture’ interval. The time spent in the ED evaluating the patient, obtaining the trauma pan-scan, consulting surgery, and finally making the joint decision to call the IR attending often takes longer than the actual IR team mobilization. A hospital could easily meet the 60 min ACS standard while still having the 1.9-hour door-to-needle time reported in this study.
Additionally, the analysis treats ‘angiography’ as a monolith. The technical realities of different embolizations are ignored. The time required to mobilize, prep, and puncture for a straightforward splenic embolization differs greatly from a massive pelvic crush injury. While the authors break down the sites of embolization, failing to stratify the timing outcomes by these specific injury sites washes out nuanced operational improvements in specific trauma pathways.
Methodologically, the study’s design introduces biases that limit its ultimate conclusions. To isolate emergent cases, the authors truncated their dataset to exclude patients who went to IR after 4 hours. However, if the goal is to evaluate whether a standard reduces systemic delays, artificially excluding the most delayed cases creates a significant selection bias. If a trauma center struggled with IR mobilization and took 5 hours to get a patient on the table, that failure is excluded from the primary analysis. Furthermore, relying on the 2023 PUF cohort as the sole post-intervention group to evaluate a 2022 mandate provides a premature evaluation window. Institutional infrastructure changes—such as securing funding for new hybrid ORs, altering technologist call structures, and hiring overnight IR coverage—often take years to implement. Expecting to see a statistically significant national drop in time-to-table in the very first year following the mandate may be overly optimistic.
These operational realities and methodological constraints help explain why the ‘door-to-needle time’ literature on endovascular trauma interventions remains heterogeneous: (1) it is largely retrospective and observational; and (2) there is an inherent tension in studies that measure ‘door-to-angiogram time’ showing a mortality signal favoring earlier intervention, while studies using the 60 min ‘decision to procedure’ metric or survival to discharge endpoints have been less consistent.2–6
Perhaps shifting the focus from ‘door-to-needle time’ to alternative, more clinically meaningful process, outcome, or structural metrics (time to hemostasis, massive transfusion protocol compliance, nonoperative management failure rates, hybrid IR/OR availability, etc) may be more informative than the door-to-procedure threshold in the trauma setting.
