4) Seroflo Traning Module-Asthma Symtoms & 5) Seroflo Traning Module-Asthma Diagnosis.pptx

Seroflo Medical Training Asthma Symtoms Symptoms of Asthma Having now looked at the pathophysiology of asthma, the symptoms: Cough, Wheeze and Breathlessness can be more easily understood. There are two components that contribute to the symptoms of asthma 1. Smooth muscle dysfunction 2. Airwa...

Seroflo Medical Training Asthma Symtoms Symptoms of Asthma Having now looked at the pathophysiology of asthma, the symptoms: Cough, Wheeze and Breathlessness can be more easily understood. There are two components that contribute to the symptoms of asthma 1. Smooth muscle dysfunction 2. Airway inflammation How Symptoms of Asthma are caused Smooth muscle dysfunction leads to:  Bronchoconstriction  Bronchial hyperreactivity  Hyperplasia of  Inflammatory mucous glands mediator release. 2B 2M How Symptoms of Asthma are caused •The inflammatory process (Airway inflammation) results in Inflammatory cell infiltration and activation Mucosal edema Cellular proliferation = hyperplasia Epithelial damage If untreated  Basement membrane thickening  Airway remodeling • These processes are Complex and Interdependent, leading to Symptoms and Exacerbation. MICE How Symptoms of Asthma are caused •This combination of events in the lungs of patients can lead to the classic symptoms of asthma: Cough Wheeze Chest tightness Breathlessness Asthma Diagnosis Diagnosis of Asthma Diagnosis should be based on: I. Symptoms II. Past medical history III. Family history IV. Physical examination V. Investigations I. Symptoms of Asthma • It is sometimes possible to make an almost certain diagnosis from asking the patient about their current symptoms. • The key symptoms of asthma are:  Cough  Wheeze  Breathlessness  Tightness across the chest • Children often only present with a history of cough on exercise or at night. • Other more general symptoms, such as tiredness or a heaviness in the chest. Symptoms of Asthma • Current symptoms and the history of symptoms are therefore very important:  What the symptoms are  When the symptoms first started  what causes the symptoms to occur (i.e. trigger factors)  How often the symptoms occur during the day or at night  How long the symptoms last  What relieves the symptoms Trigger factors of Asthma The most common triggers  Viral or bacterial infections, especially upper respiratory-tract infections.  Allergens such as pollens, house dust mites, pets (animal dander).  Occupational triggers, which may be allergens or irritants (e.g. flour used in baking, chemicals produced by soldering, working with animals, etc.).  Physical activity/exercise, cold air  Psychological factors, such as stress  Drugs such as aspirin and other non-steroidal anti-inflammatories (e.g. ibuprofen), and beta-blockers. II. Past Medical History • Many patients with asthma, particularly children, have a history of recurrent upper and lower respiratorytract infections, allergy, such as eczema and hay fever. • Adults may have a history of ‘chest problems’ and allergies as children, more likely to present with symptoms of increasing breathlessness on exercise or a persistent cough following a viral infection, e.g. a common cold. III. Family History • Patient is more ‘prone’ to asthma if other immediate family members (a parent or sibling) have a history of allergy or asthma. • Children of mothers who smoked whilst pregnant, or children living in families where they are exposed to passive smoking, are more likely to develop asthma. IV. Physical Examination • Physical examination often does not detect any abnormalities, but can exclude other possible causes, such as chest infection or heart failure. • Stethoscope may enable the clinician to identify wheeze, indicating obstructed airflow. • In children, it is important to record height and weight, because it is recognized that uncontrolled asthma can affect growth. V. Investigations • Once a comprehensive history has been taken, and the patient examined, lung function tests should be carried out to confirm the diagnosis. • In primary care, lung function can be measured in two ways: – Peak expiratory flow (PEF) – Spirometry Peak Expiratory Flow • Peak expiratory flow (PEF) is a measurement of the maximum rate of air forcibly exhaled starting from full inspiration. • It is measured in liters per minute (L/min). • Peak expiratory flow is a simple, quick and inexpensive lung-function test and is often the only one used in general practice. Peak Expiratory Flow • The greater the airway obstruction, the lower the PEF. • The patient’s predicted (expected) PEF is dependent upon race, age, height and gender. • Charts of predicted PEF have been created based on the average PEF of nonasthmatic people. • The normal range for an adult is between 450 and 600 L/min. • The patient’s PEF measurement is compared with the values on this chart and from this, the “per cent predicted PEF” can be calculated. For example, a 35-year-old, 5’ 3” female has: a predicted PEF of 465 L/min a measured PEF of 350 L/min. 350 465 x100 = 75% 1 Her measured PEF of 350 L/min is 75% of the predicted (465 L/min). Peak Expiratory Flow • A measured PEF less than 80% of predicted indicates that the patient has airway obstruction, which could be due to asthma. • However, it is important to remember that a diagnosis of asthma cannot be made from a single measurement of peak flow, and one normal PEF reading does not exclude asthma as a diagnosis. • For asthma to be diagnosed there must be a variability of 15% or more between two readings taken on two separate occasions. Spirometry • Provides more information about the condition of the airways than PEF. • The technique requires the patient to take a: • Deep breath in • Then blow out forcibly for as long as possible without interrupting the flow This procedure can be exhausting for patients and can cause coughing, wheezing and bronchoconstriction • As with PEF, measured values are compared with predicted values that are determined by age, height and gender. Spirometry • Forced vital capacity (FVC) = the total volume of air blown out of the lungs It is measured in liters (L).Normal adult values are between 2 and 5 L. An FVC that is less than 80% of predicted is abnormal and indicates disease. • Forced expiratory volume in 1 second (FEV1) = the volume of air blown out in the 1st second (L). Normal adult values are between 1 and 4.5 L. An FEV1 that is less than 80% of predicted is abnormal and indicates disease. • FEV1 /FVC ratio = the total volume of air blown out of the lungs/the volume of air blown out in the 1st second (L). In normal healthy lungs, 70% of air can be blown out in the first second and the rest expired within 4 –6 seconds. • An FEV1 /FVC ratio of less than this indicates airway obstruction Spirometry Thank You