Understanding the Different Types of Strokes

About

➀ Read and Learn

The following course content

Introduction   

Nurses are at the forefront of recognition and treatment of all types of strokes. It is imperative that we as nurses are aware that there are multiple causes and types of strokes, each of which has a varied treatment. The health care team must be mindful of newly recognized treatments for strokes related to the anatomical disorder causing it. Ischemic stroke is still the leading cause of a stroke, but we will expand our knowledge of other reasons for it during this course. The entire multidisciplinary team can make a difference in patient outcomes with swift assessment and treatment of the several types of strokes. 

Epidemiology

17 million people (global population) suffer from one of the distinct types of strokes each year, resulting in being the 5th leading cause of death. In 2010, the World Stroke Organization (WSO) declared strokes a public health emergency. Strokes occur when the blood vessels that carry oxygen and nutrients to the brain are either blocked by clots or bursts (ruptures), causing reduced blood flow and oxygen (1). Most types of strokes are 80% preventable, increasing the need for patient/family education and the aggressive treatment of risk factors. The American Stroke Association (ASA) and WSO provide both public and professional education links and materials for all. World stroke day occurs on October 29 each year to increase public awareness of all types of strokes and prevention. 

Stroke Causes

Nurses are often given rigorous training on the several types of stroke’s recognition and treatment(s). However, we often make assumptions that an ischemic stroke from a clot is the main culprit since it is the more prevalent cause. Ischemia occurs from a blockage or clot, and Transient Ischemic Attack (TIA) occurs when there is a temporary blockage or clot causing symptoms that are shorter in length and often fleeting. Some refer to TIA as a “mini-stroke.” TIA’s should be taken seriously because they can increase future risk of a stroke. A cryptogenic stroke is one in which a cause cannot be determined. 

Intracranial hemorrhage refers to bleeding that occurs within the skull, and an Intracerebral hemorrhage refers bleeding within the brain parenchyma.  

Intracerebral Hemorrhage 

The bleeding that occurs within the brain from an Intracerebral hemorrhage is due to either traumatic or non-traumatic events, which may include (4):  

• Hypertension  
• Eclampsia 
• Drug abuse
• Excess blood flow from aneurysm rupture  
• Reperfusion injury  
• Cold exposure  

Cerebral bleeding is often seen in “non-penetrating” falls in the elderly that are on anticoagulation therapy. 

Intracranial Hemorrhage

The skull is a closed space, and hence an increase in pressure from any of the contents, mainly the brain, blood, and cerebral spinal fluid (CSP), will cause an increase in intracranial pressure. Most signs and symptoms are related to this premise which was originated from the Monro-Kellie Doctrine. Unless there is a reduction of pressure of another content of the brain, any increase in the volume of CSP, blood, or edema will cause the patient to have signs of intracranial pressure or (ICP). 

Cerebral Perfusion

The concept of cerebral perfusion is important for nursing clinicians to understand, due to their frequent performance of bedside assessments, including vital signs and ICPs. Cerebral perfusion is the pressure needed to maintain blood flow to the brain for survival (5). The normal range for cerebral perfusion pressure (CPP) is 60-80 mmHg, calculated by subtracting ICP, the downward pressure, from the mean arterial pressure (MAP), the upward pressure.  

MAP is calculated either automatically or mathematically by vital sign monitors (see formula below). Remember that a tachycardic patient does have more systolic time, so the MAP will be slightly higher. Normal intracranial pressure (ICP) in adults is 5-15 mmHg. It can be regulated to some degree in the body by shifting cerebral spinal fluid into the spinal area rather than the brain and some cerebral regulation to create a steady flow of blood. 

Formulas

CPP=MAP-ICP in mmHg

MAP= (Systolic BP x1) + (Diastolic BP x 2) in mmHg

Divided by 3

Intracranial Pressure

The symptoms of ICP include headache, blurred vision, vomiting, lack of energy, and change in mood or alertness. Increased ICP can be diagnosed within history/physical, spinal tap, CAT scan, or MRI. 

A study looking at the effects of nursing interventions on intracranial pressure found some interesting results. It examined the “relationship between intracranial pressure and specific nursing interventions observed during routine care“ (6). The study recorded 3,118 direct observations at 1 minute and 5-minute time frames while monitoring intracranial pressure using a variety of methods in an intensive care unit setting. It found that drainage of cerebral spinal fluid did not have a significant effect. However, other studies have found there is some effect of cerebral spinal fluid drainage only in those with higher starting ICP pressures (greater than 25 mmHg).  

Some nurses may assume that repositioning will increase ICP, but the study found that repositioning uncomfortable items like cervical collars and endotracheal tubes, as well as raising the head of the bed, talking, decreasing stimulation and sedative medications improve and reduce ICP (6). It is vital that the multidisciplinary team recognize normal levels of ICP at 5-15 mmHg with variations up to 20-30 mmHg defined as intracranial hypertension. It is essential that we prevent significantly elevated levels of ICP, which can lead to fatal cerebral herniation or shifting of the brain contents out of the skull. 

Treatment of Cerebral Subarachnoid Hemorrhage

The initial treatment of a cerebral subarachnoid hemorrhage relates first to its diagnosis. Treatment for the various assessment symptoms are as follows:  

• Respiratory: A primary assessment of ABCs, validating whether the patient can maintain and protect their airway is necessary. If they are unable, then mechanical ventilation is warranted. Blood pressure: Blood pressure goals are typically aimed at maintaining Systolic BP less than 160 mmHg. 
• Temperature: A temperature greater than 101 is treated and imperative to brain integrity.  
• Glucose: Glucose management is imperative for brain integrity.  

The treatment related to an aneurysm is the placement of a clip at the neck of the outpouching or a coil placed inside the aneurysm, which creates intravascular clotting and prevents blood from getting into the aneurysm defect. Both procedures are performed in a specialized lab using catheters threaded through the groin up to the artery and into the brain. General treatments include treatment of electrolyte imbalance, especially hyponatremia, anemia from bleeding, and seizures. A ventricular drain may be placed if evidence of hydrocephalus (excess cerebral spinal fluid). 

Several grading systems score the severity of the hemorrhage and clinical data. The incidence of re–bleed typically occurs 24 hours after onset“. (3) The fear of delayed neurological deterioration is real and can be from cerebral ischemia, edema, or vasospasms. Some centers will utilize transcranial Doppler monitoring post–event or nimodipine (Nimotop) 60 mg orally every 4 hours after 4 days for vasospasm after subarachnoid hemorrhage. 

Free water (like hypotonic D5W) is avoided since it increases cerebral edema, and some hypertonic solutions (higher saline and dextrose percentages) may be given cautiously.  

Conclusion 

Nurses are at the forefront in recognition, monitoring, and intervention of the several types of strokes. We are especially vital since the time at the bedside enables us to assess subtle changes in vital signs, behavior, or ICP signs and symptoms and report these findings timely for intervention. Patient and family communication is essential because conditions can change rapidly, and this injury to the brain can be severe. Neurological care can be challenging but rewarding at the same time. 

➁ Complete Survey

Give us your thoughts and feedback

➂ Click Complete

To receive your certificate