Large artery strokes, a form of ischemic stroke, are the most dangerous form of stroke. About 30 percent of the stroke cases seen in Memphis are classified as large artery acute ischemic stroke, and the way patients are positioned during the immediate ‘hyperacute’ hours after they experience this severe type of stroke could impact the course of treatment and clinical outcomes.
Anne Alexandrov, PhD, RN, CCRN, ANVP-BC, NVRN-BC, FAAN, Mobile Stroke Unit chief nurse practitioner and professor in the College of Nursing at the University of Tennessee Health Science Center (UTHSC) was recently awarded over $2.3 million to study how head of bed (HOB) positioning affects patient’s ischemic stroke symptoms and clinical outcomes.
“Since 1968, it has been documented that acute ischemic stroke patients often experience clinical deterioration when the head of bed is elevated to 30 degrees or higher, whereas more recently our pilot work and other small studies have shown that zero-degree head of bed positioning improves blood flow to the ischemic brain in hyperacute large artery strokes,” Dr. Alexandrov said. “Presently, the clinical community remains divided about what position is best for these patients.”
While standard of care dictates that large artery stroke patients ultimately are treated with mechanical thrombectomy to remove the blood clot in their brain, Dr. Alexandrov and her research team hypothesize that laying a patient flat prior to surgical thrombectomy can help prevent neurological symptom worsening.
“Our preliminary studies show that brain blood flow can increase as much as 20 percent on average in ischemic territories when the patient’s bed is laid flat,” she said. “Additionally, no intracranial pressure (ICP) is present during this early period, so laying a patient flat should not increase concern about increased ICP. We also found that pneumonia is rare with zero-degree head of bed positioning when nurses cautiously monitor the airway and use side-lying positions.”
To test their hypothesis, Dr. Alexandrov and her team will conduct a randomized clinical trial at multiple sites across the United States. A new protocol that sits within current standard of care requirements for rapid thrombectomy treatment of patients with or without clot-busting medications will be executed.
“Our methods will not delay thrombectomy treatment and patients will be closely monitored with serial neurologic examinations during the positioning period,” Dr. Alexandrov said. “Use of this nursing measure holds significant promise as an innovative adjunct rescue procedure to improve large artery acute ischemic stroke symptoms, and ultimately reduce disability.
Her project titled, “ZerO Degree head positioning In Acute ischemiC stroke (ZODIAC),” is being funded for five years by the National Institutes of Health.