Bronchodilators are respiratory medicines that help in clearing of the airway in the lung muscles. Often the cause of congestion in the lungs is either an inflammation or an infection associated with it. Most of the bronchodilator mechanism of action is on the smooth muscle. Bronchodilators are classified based on their duration of action when administered - long acting and short acting.
Beta 2 agonists
These are administered through inhalers for temporary relief in case of shortness of breath. Their pharmacokinetics is predominantly associated with the movement of cilia inside the lungs to clear the presence of mucus. They are very useful in treating conditions such as asthma. Since their effect is short lived, they are not used in chronic obstructive pulmonary disease.
These drugs are similar to beta 2 agonists as they also help in removing the mucous from the channels in the lung tissue. However, the action of this respective drug is longer and hence it becomes an option to treat COPD. In order to administer this drug, a nebulizer is necessary. In the emergency medicine protocol, the drug is used in the form of a mist in the mask following which the patient is asked to inhale the drug.
These are durable action oriented class of bronchodilators and they are used a lot for COPD. The mode of action of this drug is to limit inflammation by relaxing the lung muscles and air pathways. Increased use of these drugs can trigger side effects such as nausea and light-headedness. These drugs are administered as syrups and they are only recommended in case the patient does not show prophylaxis in case of COPD.
Bronchodilators can cause many side effects and their extensive usage can also lead to damage to many organs. Bronchodilators are not recommended in case of medical conditions such as Cardiomyopathy, diabetes and hyperthyroidism as they interfere with metabolic activities of the body sometimes leading to organ failure. This is because bronchodilators also have a tendency to interfere with beta-blockers and cause hindrance in the prophylaxis of tachycardia or hypertension. They also hinder the action of antidepressants in case of conditions such as Alzheimer's disease.
PFT - Pulmonary Function Test refers to one or different types of tests that are conducted on a patient to assess the condition of the lungs and their efficiency in transferring oxygen to the blood. PFT can help diagnosing the cause of 'shortness of breath' and confirm lung diseases like Emphysema, Bronchitis and Asthma. PFT aids in measuring occupational hazards of exposure to contaminants such as asbestos or radon. It helps monitoring of disease treatment. These tests are mandatory before any major lung surgery. However, PFT is not given to patients who had a recent heart attack or has a history of heart disease.
Spirometry is a vital PFT that measures how well the lungs exhale. This diagnostic test is prescribed for patients suffering from asthma or COPD. This tests involves breathing into a mouthpiece that is connected to a spirometer. The amount of air and rate of exhalation are measured over a specific time.
Peak Expiratory Flow Rate - PEFR meter is a handheld device that measures the rate of exhalation in a patient. This PEFR test results can vary depending upon a number of factors - age, height and sex. So peak flow meters are mostly useful for monitoring the medications of some Asthma patients.
Lung volume measurement test can aid detection of restrictive lung diseases. Such patients are often unable to inhale normal volumes of air due to inflammation or scarring of lung tissue. This PFT can be done as a body plethysmograph.
Gas diffusion test measures the amount of oxygen and other gases that are absorbed into your body from your lungs.
Inhalation challenge test aids in identifying possible allergens that can cause asthma or severe respiratory allergy. Other tests to measure lung function include residual volume, gas diffusion tests, body plethysmography, inhalation challenge tests, and exercise stress tests.
Patients scheduled for PFT must restrain from use of bronchodilators or inhaler medications for few hours prior to the test. Patients are advised not to eat a heavy meal or smoke for a few hours prior to the PFT. Typical normal values for pulmonary function tests are based on the age, height, ethnicity, and sex of the person being tested. Factors such history of smoking, wheezing and obesity can affect results of PFT. Pulmonary function tests are not advised for patients who have recently suffered heart attack.
Drowning First Aid
Drowning is one of the most evaluated emergency cases in life guard training centers. Emergency medicine and paramedical support have significant roles to play while attending to a case of drowning, as it involves many primary to complex medical procedures to save a life in a short duration of time.
The primary objective of a rescue worker is to make sure that the victim gets adequate amount of oxygen in his lungs through methods such as cardiopulmonary restoration. Proper precautions are taken to avoid any kind of neck injuries during the procedure. Mouth to mouth breathing technique can be administered in water if the victim has already stopped breathing. The victim has to be moved to the shore slowly with mouth to mouth breathing at regular intervals, like five seconds. In case of obstructed airway, the Heimlich maneuver is performed by holding the victim from behind and thrusting to release the blocked airway. In certain scenarios such as spine injuries, the victim is made to lie on his stomach with his head tilted to one side and arms, torso and legs in proper position. Victims have to be covered with warm clothing to prevent hypothermia and shock. Cardiac compressions in water should not be administered as it is difficult and the risk involved is greater.
Events post first aid in drowning are evaluated by the physician and treated accordingly. Antibiotics and steroids are given in case of lung infection and inflammation. Airway obstruction post first aid is treated using bronchodilators and heated IV fluids are administered to lower the blood pressure. Stomach tubes are inserted in case of vomiting. Neck injuries and spine injuries are treated. Total immobilization of the neck is required until proper scans are taken to evaluate the intensity of the injury.
Bibliography / Reference
Collection of Pages - Last revised Date: March 23, 2019