Rethinking Routine Arterial Catheterization in Shock

The EVERDAC trial, published in the New England Journal of Medicine (2025), challenges one of intensive care’s most entrenched practices: the routine use of early arterial catheterization for patients in shock. This multicenter, randomized, noninferiority trial enrolled 1,010 ICU patients with shock and compared outcomes between early arterial line insertion (invasive strategy) and management using automated brachial cuff monitoring (noninvasive strategy).

At 28 days, mortality was 34.3% in the noninvasive group versus 36.9% in the invasive group — a nonsignificant difference that met criteria for noninferiority. In other words, omitting early arterial catheterization did not increase the risk of death. Invasive monitoring caused substantially more local complications: 8.2% experienced hematoma or hemorrhage compared with 1.0% in the noninvasive group. Catheter-related bloodstream infections were also higher (3 vs. 1 per 1,000 ICU days).

Interestingly, while cuff inflation discomfort was somewhat greater in the noninvasive arm, overall patient safety and outcomes were equivalent. Even in patients receiving vasopressors, deferring arterial access did not increase mortality or organ failure scores.

Clinical implications

This study directly questions the necessity of routine arterial lines for all patients with shock. Historically, invasive pressure monitoring has been justified by its presumed precision and ability to guide therapy minute-by-minute. Yet, the data show that modern oscillometric monitors are sufficiently accurate to maintain hemodynamic stability in most patients.

From a systems perspective, widespread arterial line use may reflect institutional habit rather than outcome-driven evidence. Invasive lines carry procedural risk, increase workload, and may promote excessive phlebotomy and anemia. Conversely, a noninvasive-first approach prioritizes patient safety without compromising care quality — provided escalation criteria and close monitoring are maintained.

Of course, arterial catheterization still has its place. Patients on high-dose vasopressors, those requiring frequent arterial blood gases, or those with rapidly fluctuating hemodynamics remain strong candidates. But for many medical ICU patients with moderate shock, noninvasive management may be both adequate and safer.

Do you believe routine arterial catheterization should remain standard practice in shock management?

• 0%Yes — it’s essential for safety and precision.
• 0%No — it should be reserved for select cases
• 0%Unsure — more evidence or experience needed

My stance

I support adopting a selective rather than routine approach to arterial catheterization. This evidence aligns with precision medicine principles — applying invasive monitoring only when it is expected to alter management or improve outcomes. For most patients with septic or distributive shock, noninvasive monitoring should be the initial standard, with arterial access reserved for escalation based on clinical thresholds.

This shift will require re-education and workflow adaptation, but it reflects the core of evidence-based practice: letting data, not dogma, dictate decisions.

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References

Muller G, et al. Deferring Arterial Catheterization in Critically Ill Patients with Shock. N Engl J Med. 2025; DOI: 10.1056/NEJMoa2502136.