Study objective: The use of recombinant tissue plasminogen activator (rt-PA) for acute ischemic stroke is controversial among emergency physicians. We survey emergency physicians to determine (1) the proportion of emergency physicians resistant to using rt-PA in the ideal setting because of the risk of symptomatic intracerebral hemorrhage; (2) the proportion of emergency physicians resistant to using rt-PA in the ideal setting because of the perceived lack of benefit; (3) the highest acceptable symptomatic intracerebral hemorrhage risk; and (4) the lowest acceptable accompanying relative improvement in neurologic outcome.
Methods: The American College of Emergency Physicians randomly selected 2,600 of its active members for anonymous Web-based or paper survey. The proportion of ED physicians resistant to rt-PA use because of symptomatic intracerebral hemorrhage risk and perceived lack of benefit, in addition to the mean acceptable symptomatic intracerebral hemorrhage risk and associated benefit, was calculated with 95% confidence intervals (CIs). Multivariable logistic regression was used to identify factors independently associated with willingness to use rt-PA in the ideal setting.
Results: The median age of the 1,105 (43%) respondents was 44 years. Overall, the mean upper limit of symptomatic intracerebral hemorrhage tolerable was 3.4% (95% CI 3.2% to 3.5%), with associated lowest acceptable mean relative improvement of 40% (95% CI 39% to 41%). Forty percent (95% CI 37% to 44%) of physicians reported that they were not likely to use rt-PA. Of these, 65% (95% CI 61% to 69%) of physicians reported this was because of the risk of symptomatic intracerebral hemorrhage, 23% (95% CI 19% to 27%) reported the cause was the perceived lack of benefit, and 12% (95% CI 9% to 15%) reported both reasons were the cause. Independently associated with willingness to use rt-PA were female sex (odds ratio 2.30 [1.57, 3.36]) and previous use of rt-PA for stroke (3.13 [2.33, 4.17]).
Conclusion: Symptomatic intracerebral hemorrhage risk is the factor most likely to preclude rt-PA use by emergency physicians. Of the 40% of physicians who would not use rt-PA, about two thirds reported this was due to symptomatic intracerebral hemorrhage risk, and about a quarter of physicians cited the relative lack of benefit. Treatment trials that aim to reduce symptomatic intracerebral hemorrhage risk to 2% to 3% are likely to stimulate the interest of emergency physicians in the use of thrombolytics for acute ischemic stroke.