The critical need for early intensive monitoring after intravenous thrombolysis in acute ischemic stroke

A revolution in stroke care

Intravenous (IV) thrombolysis has revolutionized stroke care since the landmark 1995 NINDS trial established use of tissue plasminogen activator (alteplase; tPA) in acute ischemic stroke (1). This trial, along with the European Cooperative Acute Stroke Study III (ECASS III) in 2008 and the Third International Stroke Trial (IST-3) in 2012, estimated a 3–6% risk of symptomatic intracranial hemorrhage with IV tPA (1-3), and led to national society guidelines recommending diligent blood pressure control and intensive monitoring post-administration (4).

Intensive monitoring, as defined by the American Heart Association (AHA) and American Stroke Association guidelines and currently accepted standard of care, consists of admission to an intensive care or stroke unit, performance of frequent blood pressure checks and neurological examinations, and, most importantly, the ability to emergently obtain neuroimaging and administer reversal therapies if complications arise (4).

However, with longer-term safety data, standardized protocols, and newer thrombolytics with more favorable safety profiles, some have questioned whether every patient receiving IV thrombolysis requires the current standard of monitoring, or whether certain low-risk patients may be safely monitored in lower-acuity settings.

The safety of low-intensity monitoring after IV tPA administration

In 2010, Zimmerman and Kramer analyzed 28,715 ischemic stroke patients across multiple centers, stratifying them into “high-risk” (>10% chance of requiring intensive care) and “low-risk” (<10%) groups using clinical factors such as age and National Institutes of Health (NIH) Stroke Scale score (5). Despite this complex model, 7% of patients labeled “low-risk” required intensive care interventions, with 2.5% (412 patients) dying during hospitalization (5). A subsequent analysis by Sadaka et al. validated this model in 80 patients using the APACHE database, again showing a 4.7% mortality in “low-risk” classified patients (6).

In 2015, Faigle and colleagues at Johns Hopkins developed another triaging model using magnetic resonance imaging (MRI) findings (7). Of the analyzed 209 patients receiving IV tPA, 54 patients had no diffusion restriction to indicate any acute infarction and were considered lowest risk for complications. Despite this, 5 of these 54 patients required intensive care interventions including for refractory hypertension, a key risk factor for symptomatic intracerebral hemorrhage post IV thrombolysis (7). The same year, Dr. Chang and colleagues evaluated 385 patients to assess if shorter duration (12 hours) of intensive monitoring would be enough, instead of the current 24-hour standard of care (8). The authors found a comparable 5.5% rate of symptomatic intracerebral hemorrhage as in previously published literature but showed that 20% of these hemorrhages occurred after the first 12 hours (8).

Prospective data first emerged in 2020 with the single-center OPTIMIST study, which monitored 35 patients in a low-intensity setting for 24 hours after IV tPA administration (9). No patients required intensive care interventions, but the study’s nonrandomized design and small sample size made its findings non-generalizable (9). More recently, the multicenter OPTIMIST-Main trial [2025] directly compared low-intensity monitoring to standard intensive monitoring in patients specifically with mild to moderate deficits (10). The trial reported a risk ratio of 1.03 [95% confidence interval (CI): 0.92–1.15] for unfavorable functional outcome at 90 days, providing only “weak evidence” that low-intensity monitoring after IV thrombolytics is as safe as current standards (10).

The approval and widespread adoption of TNK

The 2017 NOR-TEST and 2018 EXTEND-1A TNK trials proposed IV tenecteplase (TNK), a bioengineered recombinant DNA-derived version of alteplase, as non-inferior to alteplase with easier administration, better efficacy, shorter half-life, and lower rates of symptomatic intracranial hemorrhage and other complications (11,12). In early March 2025, the U.S. Food and Drug Administration (FDA) approved IV TNK for the treatment of acute ischemic stroke in adults and increasing clinical familiarity with IV TNK has now spurred ongoing research and discussions around expanding its use even beyond the initially established exclusion criteria based on the last-known well times (12-14).

Simultaneously, the shorter half-life of about 20 minutes and enhanced safety profile of IV TNK have prompted new discussions on whether selected patients can be safely monitored in low-intensity settings. If validated, this could optimize resources (fewer critical care stroke unit beds occupied by low-risk patients), reduce healthcare costs (deceased monitoring intensity without compromising safety), expand treatment access (safe administration of IV TNK at community or satellite hospitals without critical care units), improve workflow efficiency (decreased need for immediate transfers and prolonged bedside nursing demands), and enable earlier mobilization and discharge.

However, despite these promising benefits, our detailed PubMed review found no randomized controlled trials or high-quality studies directly comparing the required duration or intensity of monitoring after IV TNK. The issue remains largely unaddressed and warrants formal investigation, but, until more definitive evidence is available, we emphatically urge clinicians to maintain current intensive monitoring standards after IV thrombolytic administration.

A balanced standard of post-thrombolytic monitoring, with an emphasis on patient safety

Stroke care is advancing, and newer IV thrombolytics may one day bring low-intensity monitoring protocols with tremendous advantages to stroke systems of care (15-17). However, at present, predictive models and published literature have at best provided insufficient or weak evidence to support a national transition. Our review finds that the current evidence, national guidelines and accepted clinical practice do not support reducing the intensity or duration of monitoring for acute ischemic stroke patients who receive IV thrombolysis.

Instead, there must remain a strong emphasis on adequate intensive monitoring during the first 24 hours after IV thrombolytic administration. When appropriate, a drip-and-ship model championed by the AHA and Comprehensive Stroke Centers nationwide can optimize stroke outcomes by integrating the strengths of local community-driven centers with intensive care hospitals specialized in providing exceptional stroke care (4). We ourselves have implemented this approach in our large multicenter hospital system, with great success.

In conclusion: IV thrombolysis requires intensive care monitoring

Stroke patients are highly vulnerable, often with comorbidities, and receive aggressive interventions, including IV thrombolysis. Ethically and clinically, we owe them the highest level of vigilance during the first 24 hours to prevent devastating complications and improve their chances for meaningful functional recovery.

Acknowledgments

None.

Footnote

Provenance and Peer Review: This article was a standard submission to the journal. The article has undergone external peer review.

Peer Review File: Available at https://jni.amegroups.com/article/view/10.21037/jni-25-16/prf

Funding: None.

Conflicts of Interest: AIl authors have completed the ICMJE uniform disclosure form (available at https://jni.amegroups.com/article/view/10.21037/jni-25-16/coif). T.N.N. serves as an unpaid editorial board member of Journal of Neurointervention from November 2024 to December 2026. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

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