Written by Julianne Smith, RN, FNP-BC
Each year, World Stroke Day is observed on October 29th to raise awareness of its prevention and treatment. This day provides us with an opportunity to educate our patients on the severe nature and high stroke rates to ensure better care and support for survivors.
A stroke is when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot or bursts (ruptures). When this happens, a part of the brain is deprived of the oxygen it needs, and as a result, the brain cells die. Stroke is the fifth leading cause of death in the US. The two main causes of stroke are ischemic stroke (most common) and hemorrhagic stroke. Ischemic stroke is when a blood vessel that feeds the brain gets blocked, usually from a clot. Hemorrhagic stroke occurs when a blood vessel in the brain ruptures; common causes are uncontrolled high blood pressure, overtreatment with blood thinners, aneurysms, trauma and ischemic stroke leading to hemorrhage.
When it comes to recognizing a stroke, treatment is urgent, time lost equals brain cells lost. It is important to act F.A.S.T. and know the warning signs:
Face Drooping
Arm Weakness
Speech Difficulty
Time to Call 911
While it is important to recognize the signs of a stroke, it is equally important to know the risk factors associated with stroke. There are two types of risk factors, lifestyle and medical:
Lifestyle Risk Factors
• Obesity
• Physical inactivity
• Heavy drinking
• Smoking
• Recreational drug use
Medical Risk Factors
• High Blood Pressure
• High Cholesterol
• Diabetes
• Sleep apnea
• Cardiovascular Disease, including heart failure, heart defects, heart infection and arrhythmias
Stroke caused by heart disease is primarily due to an embolism forming on the atrial or ventricular wall or the left heart valves. The most significant causes are atrial fibrillation, myocardial infarction, prosthetic heart valves, rheumatic heart disease and ischemic cardiomyopathy. In atrial fibrillation, the mechanism of stroke is that a clot forms in the fibrillating atrial appendage, which can dislodge and cause a stroke. A recent myocardial infarction can be a source of emboli. Paradoxical emboli can also form when a venous clot migrates to the arterial circulation, usually via a patent foramen ovale (PFO) or atrial septal defect (ASD). The diagnosis of a PFO can be made with a bubble-contrast echo. Bacterial endocarditis can also cause vegetation on the heart valves and can give rise to septic emboli.
Complications of stroke include paralysis, difficulty swallowing/talking, memory loss and changes in behavior. Prevention includes controlling blood pressure, lowering cholesterol, smoking cessation, managing diabetes, exercise, limiting alcohol, treating sleep apnea and avoiding recreational drugs.
Preventive medications include antiplatelets (aspirin) and anticoagulants such as Coumadin. There are also newer anticoagulants: Pradaxa, Xarelto, Eliquis and Savaysa, which do not require blood testing and have a lower bleeding risk. Diagnosis of stroke is made by a clinical exam and can be further confirmed and classified through additional testing such as a CT scan, MRI, carotid duplex, echocardiogram and blood tests.
The goal of treatment is to restore blood flow to the brain. For ischemic stroke treatment, the gold standard treatment is an IV medication called tissue plasminogen activator (TPA), which breaks up a clot. Hemorrhagic stroke treatment includes controlling bleeding with drugs or transfusions to reverse blood thinners, surgery to evacuate the blood and relieve the pressure, surgical clipping or coil procedure.
The care after a stroke focuses on recovery and rehabilitation to restore as much function as possible.
References:
Fauci, A.S; Braunwald, E; Kasper, D.L; Hauser, S.L; Longo, D; Jameson, J.L; Loscalzo, J (2008). Harrison’s Principles of Internal Medicine (17th ed). New York: McGraw Hill
Stroke. Retrieved October 10, 2020 from https://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes