Breathing Difficulties: Stroke's Hidden Impact

A stroke occurs when blood carrying oxygen cannot reach the brain, resulting in brain cell damage and potential death. Strokes can affect several areas of the body, depending on which part of the brain is impacted, and can cause long-term symptoms. One of the areas affected by a stroke is the part of the brain that controls breathing. This can lead to respiratory abnormalities, including a loss of airway protection and changes in the respiratory drive and breathing pattern. As a result, individuals may experience shortness of breath, also known as dyspnea, and other breathing difficulties. In some cases, a tracheotomy tube may be necessary to assist with breathing. These breathing issues can be short-term, but some individuals may experience long-term breathing problems, particularly during sleep, with sleep apnea being a common complication.

A stroke can cause difficulty breathing, requiring a tracheotomy tube to be placed in the neck

A stroke can cause difficulty breathing, which may require a tracheostomy tube to be placed in the patient's neck. This procedure involves creating a small opening in the neck to insert a tube into the trachea, providing an airway for breathing.

Stroke is a leading cause of neurological disability, and respiratory abnormalities are among its wide-ranging effects. It can influence the central control of the respiratory drive, breathing pattern, airway protection, and the mechanics of inspiration and expiration. During the acute phase of a stroke, changes in consciousness, cerebral edema, and direct damage to brainstem respiratory centers can result in abnormalities in respiratory patterns and loss of airway protection. Respiratory failure may occur, depending on the location and extent of the stroke.

Dysphagia (difficulty swallowing) is a common complication following a stroke, and it can lead to aspiration and pneumonia. In some cases, dysphagia may be so severe that tube feeding and swallowing therapy alone are insufficient to prevent aspiration. In such situations, a tracheostomy may be indicated as a temporary measure to protect the airway during rehabilitation.

More often, tracheostomies are performed in stroke patients who require intensive care and mechanical ventilation. Long-term ventilation and prolonged insufficient airway protection are the main indications for tracheostomy in this context. Advantages of tracheostomy over prolonged orotracheal intubation include reduced pharyngeal and laryngeal lesions, improved oral hygiene, better nursing care, and increased patient comfort.

The optimal timing of tracheostomy is unclear, and stroke patients have been understudied in this regard. However, a single randomized pilot study on early tracheostomy in ventilated stroke patients found the procedure to be feasible and safe, with reduced sedation requirements. Additionally, retrospective studies suggest that early tracheostomy may be associated with shorter intensive care unit stays. While the procedural risk is generally low, tracheostomy can have serious complications, including arterial bleeding and accidental decannulation.

Respiratory failure may occur depending on the location and extent of the stroke

A stroke can cause a person to have difficulty breathing, and in some cases, respiratory failure may occur depending on the location and extent of the stroke. The respiratory control centres are located in the brainstem, and a stroke in this area can cause specific patterns of respiratory dysfunction. During the acute phase of a stroke, changes in consciousness, cerebral oedema, and direct damage to brainstem respiratory centres can affect the central control of breathing, leading to abnormalities in respiratory patterns and loss of airway protection. This can result in common acute complications such as dysphagia, aspiration, and pneumonia.

The impact of a stroke on respiratory function depends on the severity and site of the neurological injury. Brainstem infarcts, based on their location, size, and bilaterality, can alter the sensitivity and response to input from peripheral and central chemoreceptors, affecting the rate and rhythm of respiration. Large, severe strokes can compromise the regulation of breathing due to cerebral oedema and biochemical changes in the brain, even without direct brainstem involvement.

In addition, the size and location of an acute stroke lesion can influence the occurrence of central periodic breathing (CPB). CPB is associated with large acute stroke lesions in the cerebral hemispheres and severe mass effect on brain imaging. This can lead to cyclical increases in breathing rate and depth, followed by reductions or complete cessations of nasal airflow and respiratory effort.

While respiratory abnormalities often improve over time, sleep-disordered breathing (SDB) can persist in the subacute and chronic phases after a stroke. SDB includes central sleep apnea (CSA) and obstructive sleep apnea (OSA), with OSA being the most common among stroke survivors. OSA is associated with adverse outcomes, including an increased risk of recurrent stroke and worse post-stroke recovery.

Dyspnea (shortness of breath) is a common symptom after a stroke, affecting 44% of survivors

A stroke occurs when blood carrying oxygen cannot reach the brain, causing brain cells to become damaged and potentially leading to death. The effects of a stroke depend on which part of the brain is affected, and while some consequences are short-term, others can cause long-term issues.

One common symptom affecting 44% of survivors is dyspnea, or shortness of breath. Dyspnea can cause difficulty in breathing, tightness in the chest, and gasping for air. It can come on suddenly or get worse over time, and can be both emotionally and physically challenging to cope with.

Dyspnea can be caused by a stroke's impact on the respiratory system, including the weakening of the muscles used for breathing. It can also be caused by damage to the area of the brain that controls eating and swallowing, known as dysphagia. This can lead to food or liquid entering the airway and settling in the lungs, causing infections and pneumonia.

The respiratory mechanics of stroke survivors are often impaired, contributing to worse cardiopulmonary health. As a result, survivors may experience symptoms such as dyspnea and fatigue. Additionally, reduced cough strength can increase the risk of pneumonia after a stroke.

The central control of breathing can also be affected by a stroke, influencing the respiratory drive and breathing pattern, airway protection, and the mechanics of inspiration and expiration. This can result in respiratory dysfunction, with common acute complications including dysphagia, aspiration, and pneumonia.

Furthermore, sleep-disordered breathing is common after a stroke, with over 70% of survivors developing obstructive sleep apnea. This can lead to an increased risk of a recurrent stroke and worse post-stroke recovery.

The presence of dyspnea can have a significant impact on the daily lives of stroke survivors. It has been linked to activity limitations and restrictions in community participation, with survivors experiencing dyspnea being six times more likely to report activity limitations and twice as likely to report restrictions in social participation.

Early detection and appropriate management of dyspnea are crucial to improving the quality of life for stroke survivors. This includes pulmonary rehabilitation, breathing control techniques, and chest-clearing exercises to help manage symptoms.

Sleep-disordered breathing is common in the subacute and chronic phases of a stroke

Sleep-disordered breathing (SDB) is a common occurrence in the subacute and chronic phases of a stroke. SDB is a syndrome of upper airway dysfunction during sleep, which can range from snoring to obstructive sleep apnea (OSA). Obstructive sleep apnea involves a significant decrease or cessation of airflow despite breathing efforts.

Stroke survivors often experience disturbances in respiratory function, which can lead to gas exchange abnormalities or the need for mechanical ventilation. These respiratory complications can include SDB, which may, in turn, play a role in the pathogenesis of cerebral infarction. SDB can manifest as central sleep apnea (CSA) or OSA. CSA is related to changes in the brainstem's generation of respiratory rhythm during sleep, while OSA results from decreased activity of muscles that maintain airway patency.

OSA is a significant risk factor for cardiovascular morbidity, and it has been associated with an increased risk of nonfatal myocardial infarction and stroke. Over 70% of stroke survivors suffer from OSA, which is linked to adverse outcomes such as an increased risk of recurrent stroke and worse post-stroke recovery.

The presence of SDB in stroke patients can lead to a sustained reduction in oxyhemoglobin saturation and sleep fragmentation, affecting the quality and quantity of sleep. This can result in daytime fatigue, cognitive deficits, and impaired cardiovascular fitness in stroke survivors.

The management of SDB in stroke patients is crucial for improving outcomes. Treatment options include non-pharmacological measures such as diet, weight loss, positional therapy, and the use of devices like continuous positive airway pressure (CPAP) or oral appliances. CPAP is recommended for patients with moderate-to-severe apnea, while oral appliances are an alternative for those with mild to moderate OSA.

A stroke can cause dysphagia (difficulty swallowing), which can lead to aspiration and pneumonia

A stroke can cause dysphagia, or difficulty swallowing, which can have serious health consequences if left untreated. Dysphagia is a common problem for people who have had a stroke, with approximately 30% of patients experiencing it. It can manifest as an inability to swallow solids, liquids, or both, and is often accompanied by other symptoms such as a hoarse voice, recurrent pneumonia, coughing, and weight loss.

Dysphagia occurs when a stroke disrupts the swallowing network in the cerebral cortex, which includes the insula, cingulate gyrus, prefrontal gyrus, somatosensory cortex, and precuneus regions. This disruption impairs the command centre for swallowing, leading to difficulties in the oral, pharyngeal, and oesophageal phases of swallowing.

One of the most serious complications of dysphagia is aspiration pneumonia. Aspiration occurs when swallowed food or liquid enters the airway and lungs instead of the oesophagus. Normally, this would trigger a violent cough; however, a stroke can reduce sensation, resulting in "silent aspiration" where the person is unaware that they are aspirating. This can lead to aspiration pneumonia, a serious infection that increases the patient's catabolic condition and nutritional demands. The patient's inability to swallow properly further exacerbates the problem, creating a vicious cycle of malnutrition, dehydration, and infection.

The risk of aspiration and subsequent pneumonia is particularly high in the early stages of a stroke due to abnormal cognition. Therefore, prompt evaluation and management of dysphagia are crucial to prevent these potentially life-threatening complications. Patients may require a modified diet, feeding tube, or swallow therapy to improve their swallowing function and reduce the risk of aspiration.

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