Swimming Strokes: Different Techniques For A Better Swim

Strokes are a life-threatening medical emergency that occurs when there is an interruption to the blood supply to the brain, causing brain cells to die due to lack of oxygen. Strokes can be broadly classified into two main categories: ischemic strokes, caused by a blockage in an artery or vein; and hemorrhagic strokes, caused by bleeding in or around the brain. Ischemic strokes, which account for about 80-87% of all strokes, can be further divided into thrombotic and embolic strokes, depending on whether the blood clot forms in the blood vessels inside the brain or elsewhere in the body. Hemorrhagic strokes, making up about 13% of strokes, can be classified as intracerebral or subarachnoid hemorrhages, depending on whether the bleeding occurs inside the brain or between the brain and its outer membrane.

Ischemic strokes (87% of all strokes)

There are two main types of strokes: ischemic strokes and hemorrhagic strokes. Ischemic strokes, which account for about 87% of all strokes, occur when a blood vessel supplying blood to the brain is obstructed by a blockage or clot. This can be caused by a thrombotic event, where a blood clot develops inside the blood vessels in the brain, or an embolic event, where a clot or debris from elsewhere in the body blocks a blood vessel in the brain.

The urgent treatment for ischemic strokes is clot removal, which can be done through medication and mechanical treatments. Medication with drugs like Alteplase IV r-tPA, approved by the FDA, can dissolve the clot and improve blood flow. Mechanical treatments, such as thrombectomy, use devices like a wire-cage stent retriever to remove the clot.

Ischemic strokes pose a significant burden on public health systems and individuals, leading to morbidity and mortality worldwide. They can cause long-term disabilities, particularly affecting mobility in older adults. Understanding the underlying mechanisms, risk factors, and management strategies is crucial to mitigate the impact of this serious neurological condition.

The risk factors and causes of ischemic strokes include atherosclerosis, or fatty deposits (plaques) that line the vessel walls; atrial fibrillation, an irregular heartbeat that can cause clots in the heart; high blood pressure; diabetes; and high cholesterol.

The symptoms of ischemic strokes depend on the area of the brain affected and can vary widely. They can include hemiparesis, facial paralysis, sensory loss in the face and upper extremities, aphasia, ataxia, nausea, vomiting, headache, and dysarthria.

It is crucial to seek immediate treatment for ischemic strokes, as timely revascularization treatments can improve outcomes. The door-to-needle time of 60 minutes is recommended for acute ischemic stroke patients who qualify for thrombolytics.

To prevent ischemic strokes, it is important to address modifiable risk factors such as hypertension, diabetes, high cholesterol, and smoking through lifestyle modifications and pharmacological interventions. Additionally, raising awareness about the warning signs of stroke and promoting timely access to medical care can help expedite treatment and minimize damage.

Hemorrhagic strokes (13% of all strokes)

Hemorrhagic strokes, constituting about 13% of all strokes, occur when a weakened blood vessel, such as an aneurysm or an arteriovenous malformation (AVM), ruptures and bleeds into the brain. This bleeding results in the compression of the surrounding brain tissue, leading to a loss of normal function. The two primary types of hemorrhagic strokes are intracerebral hemorrhage (bleeding within the brain) and subarachnoid hemorrhage (bleeding between the brain and the membranes covering it).

Intracerebral hemorrhage, often caused by high blood pressure, can lead to coma or death due to the rapid and severe bleeding. Subarachnoid hemorrhage, commonly resulting from an aneurysm or AVM, can cause bleeding between the brain and the meninges, the membranes covering the brain.

The signs and symptoms of a hemorrhagic stroke include sudden numbness or weakness on one side of the body, trouble speaking or seeing, dizziness, severe headaches, loss of balance or coordination, and paralysis of one side of the body. Given the urgency of the condition, immediate emergency medical care is crucial to prevent life-threatening complications and minimise brain damage.

Diagnosis of a hemorrhagic stroke involves a comprehensive medical history and physical examination. Imaging tests such as magnetic resonance imaging (MRI) or computed tomography (CT) scans play a vital role in differentiating between ischemic and hemorrhagic strokes. Additionally, an electroencephalogram (EEG) or lumbar puncture may be conducted to confirm the diagnosis.

Treatment options for hemorrhagic strokes include interventional radiology and neurosurgical procedures like surgical clipping and coil embolization, aimed at stopping the bleeding and reducing intracranial pressure. Medications are also administered to reduce swelling, prevent seizures, and manage pain. The overarching goals of treatment are to prevent life-threatening complications, reduce disability, and restore as much normal functioning as possible through rehabilitation.

Transient ischemic attack (TIA) or mini-strokes

Transient ischemic attack (TIA) or "mini-stroke" is a temporary blockage of blood flow to the brain, often caused by tiny blood clots or plaque debris that temporarily block an artery supplying blood to the brain. These clots can form in the blood vessels inside the brain or travel there from elsewhere in the body, such as the heart. High blood pressure is the main risk factor for TIAs, and other risk factors include irregular heartbeats, family history of stroke, high cholesterol, and increasing age, especially after 55. People with these risk factors are more likely to experience a TIA or stroke.

The symptoms of a TIA are similar to those of a stroke and can include changes in alertness, senses, mental function, muscle weakness or paralysis, dizziness, and bladder or bowel control issues. These symptoms typically last from a few minutes to 24 hours and then disappear, with the blockage breaking up and blood flow restoring on its own, leaving no permanent brain damage. However, a TIA is a serious warning sign that a more severe stroke may occur in the near future, with a 10% chance of a full-blown stroke within three months, and the greatest risk being in the first 48 hours to seven days after a TIA. Therefore, it is crucial to seek immediate medical attention if you experience any of these symptoms, as prompt evaluation and treatment can help prevent a potentially debilitating or deadly stroke.

The distinction between a TIA and a stroke lies in the duration of reduced blood flow and the extent of brain damage. While a TIA is transient, with symptoms usually lasting only a few minutes to an hour, a stroke involves a prolonged decrease in blood flow, resulting in permanent brain damage. Additionally, a TIA does not cause brain tissue death, whereas a stroke can cause brain cells to die within minutes due to oxygen deprivation.

To diagnose a TIA, a healthcare provider will perform a complete physical exam to check for heart and blood vessel problems and evaluate nerve and muscle function. They may use a stethoscope to listen for abnormal blood flow sounds, such as a bruit, in the carotid artery or other arteries. Various tests, such as CT scans, MRIs, angiograms, and electrocardiograms, may be conducted to rule out a stroke or identify underlying disorders.

If you experience any symptoms suggestive of a TIA or stroke, it is crucial to act quickly and seek medical attention immediately. Do not ignore these warning signs, as prompt evaluation and treatment can significantly impact your health outcomes.

Thrombotic strokes

A thrombotic stroke is a type of ischemic stroke. It occurs when a blood clot (thrombus) forms inside one of the brain's arteries, blocking blood flow to a part of the brain. This causes brain cells in that area to stop functioning and die quickly due to a lack of oxygen and nutrients. Thrombotic strokes are usually caused by a blood clot that develops in the blood vessels inside the brain, often in arteries that have already been narrowed by atherosclerosis (a buildup of fat and lipids inside the walls of blood vessels).

The risk factors for thrombotic strokes include high blood pressure, smoking, and a family history of thrombotic stroke. Additionally, conditions like high cholesterol, diabetes, and a sedentary lifestyle can increase the likelihood of atherosclerosis, which is a major contributor to thrombotic strokes.

Symptoms of a thrombotic stroke can vary depending on the affected area of the brain. They may appear suddenly or develop gradually over several hours. Some common symptoms include:

• Weakness, numbness, or paralysis on one side of the body
• Double or blurred vision
• Sudden difficulty walking or maintaining balance
• Problems understanding speech
• Dizziness or confusion
• Severe numbness in any part of the body
• Visual disturbances, including sudden loss of vision
• Coordination problems in the arms and hands
• Slurred speech or inability to speak

If you or someone you know is experiencing any of these symptoms, it is crucial to seek immediate medical attention. Thrombotic strokes are a medical emergency, and prompt treatment can significantly impact recovery.

Embolic strokes

The risk factors for embolic strokes include high blood pressure, lack of regular exercise, and a family history of stroke, heart attack, or related conditions. The symptoms of an embolic stroke are similar to those of other types of strokes and include difficulty speaking or understanding words, weakness or numbness, paralysis in the limbs or face, blurred vision or blindness, and difficulty swallowing.

Prompt diagnosis and treatment are crucial for embolic strokes to limit brain damage and reduce the risk of complications. Doctors may use imaging techniques such as CT scans, MRIs, and ultrasounds to diagnose embolic strokes and determine their cause. Treatment options include administering clot-busting medications, performing mechanical clot removal, and surgery to open blocked arteries.

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