Virtually every stroke patient who was administered a clot-busting medication in clinical practice, and who was included in a study of such cases, was given the medication with deviations from recommended protocols, according to a journal article by a Yale physician.
Dawn Bravata, M.D., assistant professor of internal medicine at Yale School of Medicine, and her co-researchers, evaluated the medical records of 63 patients who received thrombolytic therapy at 16 Connecticut hospitals between 1996 and 1998. The researchers found that 67 percent of patients had a major protocol deviation and 97 percent had major or minor protocol deviations.
"Major deviations from protocol at times led to serious or fatal consequences," said Bravata.
The deviations ranged from incorrect dosage and waiting too long to administer the drug, to giving it to patients for whom it was contraindicated, such as those with a history of bleeding, evidence of active internal bleeding, high blood pressure, history of a previous stroke within the past three months and a history of intracranial bleeding. The mortality rate and serious extracranial hemorrhage rate was higher among patients who received this therapy in clinical practice as compared with those who were adminstered the clot busting drug during the landmark National Institutes of Health clinical trial. In cases where there were no major protocol deviations, the mortality rate for patients in clinical practice was similar to those in the clinical trial.
"Studies have shown that thrombolytic therapy for acute stroke can be given safely and effectively in study settings with experienced clinicians, but the patient outcomes associated with this therapy in routine clinical practice were not known. This is why we conducted our investigation," said Bravata, principal investigator of the study published this month in the Archives of Internal Medicine.
Bravata said the study also showed that if the clot-busting drug is administered correctly, there are few or no adverse effects. She said this is important because there has been some reluctance by the medical community to use thrombolytic therapy because it is potentially dangerous, but her research findings suggest that thrombolytic therapy is safe when it is given without protocol deviations.
Currently experts recommend that the therapy be started within three hours after an ischemic stroke, which is the most common form of stroke occurring at the rate of about 600,000 cases each year. An ischemic stroke occurs when blood flow in the brain is blocked by a clot or narrowed artery. However, clot busters can be harmful when administered to patients who suffered a hemorrhagic stroke, which is caused by bleeding in the brain.
"Systems should be put in place that ensure the identification of all eligible patients and the appropriate treatment of patients in a timely manner, including measures that guarantee that physicians have the necessary information to promote the optimal care of patients with acute stroke," the researchers said in their conclusion. "It took more than a decade for organized systems of care to be instituted for myocardial infarction and trauma from motor vehicle crashes, and subsequently for patient outcomes to improve. The results of our study offer a point of departure for strengthening this process for stroke care."
Co-authors included Nancy Kim, M.D., John Concato, Harlan Krumholz, M.D., and Lawrence Brass, M.D., all of Yale School of Medicine.
Contact
Office of Public Affairs & Communications
203-432-1345