In this episode, I’ll discuss how long patients need to be monitored in the ICU after receiving alteplase for acute ischemic stroke.
The typical length of stay for a patient in the ICU after receiving alteplase for acute ischemic stroke is 24 hours. This monitoring period is primarily to detect a conversion of the stroke from ischemic to hemorrhagic, which occurs about 6% of the time.
A recent article in the journal Stroke examined the time from alteplase to the onset of intracranial hemorrhage to identify the ideal duration of monitoring in the ICU.
The study was a retrospective sample at a single center over a 13 year period consisting of 385 patients. 5.5% of patients developed symptomatic intracranial hemorrhage after a mean of 8.5 hours. 81% of patients who experienced intracranial hemorrhage did so within 12 hours of receiving alteplase.
The authors of this study concluded:
sICH associated with the administration of intravenous tPA typically occurs within the first 12 hours of treatment. Longer monitoring in an intensive care unit-like setting may be unnecessary for most individuals.
While this study does identify that most patients in the sample would be OK with just 12 hours of monitoring, there are at least two factors that warrant further investigation rather than the adoption of these results.
First, a single-center study with only 21 events of intracranial hemorrhage is too small to extrapolate to other centers.
Second, the authors suggest that one of the reasons a shorter monitoring time could be used is:
Because the half-life of tPA is much shorter than 24 hours
Unfortunately, the plasma half-life of alteplase does not entirely account for the drug’s effects on hemorrhage risk. Even after it has cleared from the plasma, alteplase continues to suppress fibrinogen levels in many patients.
One study of 128 patients found that a low fibrinogen level (below 150 mg/dL) was the sole factor associated with hematoma expansion. This is why guidelines recommend attempting to reverse thrombolytic therapy if intracranial hemorrhage occurs within 24 hours of administration of alteplase.
Rather than a blanket recommendation to shorten the duration of monitoring of all post-alteplase stroke patients, I expect future studies to focus on better identifying the subgroup of patients that are not likely to require ICU-level monitoring after alteplase for stroke. This may involve a determination of fibrinogen levels, or it may involve a scoring system similar to what has been suggested with the ICAT (intensive care after thrombolysis) score.
The ICAT score combined information about race, sex, SBP, and NIHSS to predict which patients would need a critical care level-intervention after receiving alteplase for stroke. A score ≥2 was associated with over 13 times higher odds of critical care resource utilization compared to a score <2, predicting critical care resource utilization with 97.2% sensitivity and 28.0% specificity.
Members of my Hospital Pharmacy Academy have access to resources to save time and help you in your practice including practical trainings from a pharmacist’s point of view on how to treat intracranial hemorrhage due to alteplase, blood pressure control in acute stroke, and the pharmacist’s role on the stroke team. To get immediate access go to pharmacyjoe.com/academy.
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