Introduction:
Acute aggravation of chronic obstructive pulmonary disease (COPD) can lead to morbidity. Antibiotics, corticosteroids, and nebulized bronchodilators are administered to such individuals. Intravenous magnesium is widely used in the treatment of asthma. It is an affordable bronchodilator and has minimal side effects. Few studies evaluate magnesium's effectiveness on acute COPD exacerbation, but their results are contradictory.
What Is COPD?
COPD, or chronic obstructive pulmonary disease, is a group of chronic inflammatory diseases of the lungs that cause obstructed airflow from the lungs. Lung diseases such as emphysema and bronchitis are the common conditions contributing to COPD. These two conditions usually occur together. It is usually caused by long-term exposure to certain irritating gases, air pollution, dust, and smoke, most often from cigarette smoke. Individuals with COPD are at an increased risk of developing certain other conditions like lung cancer, heart disease, etc. It is a progressive disease that worsens with time but is curable. With proper management, many people with COPD can get better and reduce the risk of developing other associated conditions.
Chronic bronchitis is the inflammation of the lining of the bronchioles (tubes carrying air to and from the lungs). This leads to the formation and build-up of mucus, further narrowing the tubes and leading to difficulty in the inflow and outflow of air. A wet cough and mucus production characterize it.
Emphysema is a condition of the lungs wherein the air sacs or alveoli at the end of the smallest lung tubes (bronchioles) are destroyed due to exposure to pollutants like cigarette smoke and other irritating gases and particulate matter. This damage to the walls of the air sacs leads to breathing difficulty.
What Is Severe COPD Exacerbation?
The acute exacerbations of COPD occur after an infection, irritation, and temperature changes. Depending on the severity, these exacerbations are often associated with increased infiltration of specific white blood cells and eosinophils (a type of blood cell). In mild exacerbations, there is significantly less airflow obstruction, while severe exacerbations greatly affect gaseous exchange in the lungs. The clinical features of severe exacerbation of COPD include inflammation, edema (buildup of fluid), mucous hypersecretion, and bronchoconstriction (constriction of the airways). This results in hypoxia or inadequate supply of oxygen and vasoconstriction of blood vessels of the lungs impairing perfusion.
What Is Magnesium Sulfate?
Magnesium sulfate is a drug that is either intravenous or inhalational and has been shown to promote the dilation of the bronchial air passages and to improve lung function in asthmatic individuals. The administration of magnesium sulfate in patients with mild COPD is associated with reduced lung hyperinflation and strengthened respiratory muscles. Magnesium administered either intravenously or via inhalation therapy has been found to be quite safe. The improvement in lung airflow and the beneficial effect of intravenous magnesium on inhalation via nebulization with beta-2 agonists is an added advantage.
Various studies have shown that magnesium levels in COPD decrease to a great extent. This deficiency is not easily identifiable. Magnesium deficiency could also lead to an inflammatory state in the body via increased activation of specific white blood cells and release of certain allergy-causing chemicals, thus producing mucus. Magnesium blocks calcium and hinders the release of acetylcholine on the neuromuscular plate. Therefore it plays an essential role in the strength of the muscles. In COPD, these effects lead to an increase in the mechanism of the disease. Thus magnesium deficiency leads to an increased constriction of the bronchioles and also the frequency of the acute exacerbations of COPD.
What Is the Role of Intravenous Magnesium in Severe COPD Exacerbation?
The treatment of acute exacerbation of COPD is aimed at stopping the pathogenesis and altering the precipitating factors leading to the condition, such as infections. In spite of the lack of proper evidence, the inhaled short-acting beta-agonists (a class of drugs that relax and widen the airways in the lungs), with or without anticholinergics, relieve dyspnea (shortness of breath) and improve respiratory parameters in individuals with COPD. In addition, the use of steroids and antibiotics is significant in reducing inflammation and suppression of the infection thereby enhancing further resolution of acute exacerbation. Depending on the clinical condition, the individual might need respiratory support and admission to the intensive care unit (ICU).
The intravenous administration of Magnesium sulfate, along with bronchodilators, is helpful in the treatment of severe asthma or when the response to the bronchodilators is not as expected. This bronchodilatory effect occurs through the relaxation of the bronchial smooth muscle. However, evidence for the use of inhaled Magnesium sulfate in acute exacerbations of asthma, either alone or in addition to bronchodilators, is lacking, and further research is required to establish its potency. Intravenous Magnesium sulfate has also been used in acute severe COPD exacerbation but with mixed results.
Several trials have been conducted to find out the benefit of intravenous magnesium sulfate administration in people with COPD. The use of intravenous Magnesium sulfate in the treatment of acute exacerbation of COPD remains unclear as the number of trials conducted on the same is limited. Some evidence has been provided on the improvement of the airflow within the lungs with intravenous Magnesium sulfate. However, the clinical benefit of the improvement in airflow is doubtful, as the clinical outcomes, such as the need for ICU admission, non-invasive or invasive ventilation, duration of hospital stay, or re-admission, were improved by the administration of intravenous magnesium.
The treatment of COPD is usually focused on improving both the acute and chronic symptoms, reducing the exacerbations, and enhancing the quality of life. The standard of care maintenance therapy for COPD includes inhaled bronchodilators, either alone or with inhaled glucocorticoids.
Conclusion:
Chronic obstructive pulmonary disease is one of the causes of death across the world. Acute exacerbation of COPD (AECOPD) is a severe condition of the disease. The intravenous magnesium sulfate administration has been found to enhance its bronchodilator effects. Magnesium is involved in many enzymatic processes. It relaxes the smooth muscles of the bronchioles through its calcium channel-blocking effects and inhibits the release of acetylcholine. It also has an anti-inflammatory effect. The justification for the use of magnesium in COPD is its asthma-curing efficiency. However, there is still no conclusive evidence on Magnesium sulfate for the treatment of acute exacerbation of COPD.
