Respiratory Diseases (Grade 11 NSC Matric Life Sciences): Revision Notes
Respiratory Diseases
What are respiratory diseases?
Respiratory diseases are conditions that affect your breathing system, including your lungs, airways, and other parts involved in getting oxygen into your body. These diseases can be caused by three main types of harmful agents that damage your respiratory system:
- Pathogens - These are disease-causing organisms like viruses, bacteria, and fungi that can infect your respiratory system
- Environmental pollutants - Harmful substances in the air such as pollen, smoke, and dust that irritate your breathing passages
- Carcinogens - Cancer-causing substances that can lead to tumours in your lungs and airways
Understanding these causes helps us see why protecting our respiratory system is so important for maintaining good health. Each type of harmful agent affects your respiratory system differently, which is why different diseases require different treatments.
Common respiratory diseases and disorders
There are six major respiratory diseases that commonly affect people. Each has different causes, produces different symptoms, and requires different treatments. Let's explore each one.
Recognizing Early Symptoms
Many respiratory diseases share similar early warning signs like persistent coughing, breathing difficulties, or unusual mucus production. Early recognition and treatment can prevent these conditions from becoming more serious and improve recovery outcomes.
Bronchitis
Bronchitis occurs when the bronchi (main air passages to your lungs) and bronchioli (smaller airways) become infected and inflamed. This condition is usually caused by viral, bacterial, or fungal infections that attack these important breathing passages.
Key symptoms include:
- Red, swollen airways that become inflamed
- Excessive mucous production that clogs your airways
- Fever as your body fights the infection
Treatment focuses on: Using antibiotics to fight bacterial infections, taking pain tablets to reduce discomfort, and getting plenty of rest to help your body recover.
Hay fever
Hay fever is an allergic reaction that happens when your immune system overreacts to normally harmless substances like dust, pollen, and mould spores. These substances are called allergens, and they trigger the release of histamines in your body, which cause the uncomfortable symptoms.
Key symptoms include:
- Itchy, watery eyes, runny nose, and scratchy throat
- Inflammation of the lining inside your respiratory passages
- Increased mucous production
- These symptoms occur because histamines are released when allergens are detected
Treatment involves: Taking antihistamines to block the histamine reaction, using eye drops to soothe irritated eyes, and applying nose sprays to reduce inflammation.
Asthma
Asthma is a chronic condition where your airways become overly sensitive to certain substances, causing them to narrow and making breathing difficult. This allergic reaction can be triggered by various environmental factors.
Key symptoms include:
- Tight feeling in your chest
- Difficulty breathing, especially breathing out
- Wheezing sounds when breathing and persistent coughing
Treatment includes: Using preventative medicines daily to reduce inflammation, carrying steroid pumps (inhalers) for quick relief during attacks, and taking anti-allergy medications to reduce sensitivity.
Emphysema
Emphysema is a serious lung disease primarily caused by long-term exposure to harmful substances that damage the tiny air sacs (alveoli) in your lungs. The main causes are inhaling cigarette smoke and breathing in dust or poisonous gases, particularly from mining or industrial work.
Key symptoms include:
- Poor gas exchange because damaged alveoli cannot transfer oxygen effectively
- Severe breathing difficulties, even during light activities
- Fluid build-up in the lungs
- Thick, sticky phlegm that is difficult to cough up
Treatment requires: Using oxygen ventilators to help with breathing, as the lungs can no longer function properly on their own.
Lung cancer
Lung cancer develops when cells in your lungs grow uncontrollably to form tumours. The primary cause is smoking tobacco, but exposure to other carcinogens (cancer-causing substances) also increases your risk significantly.
Key symptoms include:
- Persistent breathing difficulties that get worse over time
- Blood in your sputum (the mucus you cough up) - this is a serious warning sign
Treatment options include: Surgery to remove tumours, radiation therapy to destroy cancer cells, chemotherapy to stop cancer growth, and oxygen therapy to help with breathing.
Tuberculosis
Tuberculosis (TB) is a serious infectious disease caused by bacteria called Mycobacterium tuberculosis. This disease spreads through the air when infected people cough or sneeze, making it highly contagious.
Key symptoms include:
- Excessive, persistent coughing that doesn't go away
- Extreme tiredness and weakness
- Loss of appetite leading to significant weight loss
Treatment requires: A long course of specific antibiotics designed to kill the tuberculosis bacteria. Treatment must be completed fully to prevent the disease from returning.
The effects of smoking on respiratory organs
Cigarette smoking is one of the most dangerous threats to your respiratory system. Tobacco smoke contains over 4,000 harmful chemicals, but three main ingredients cause the most damage to your breathing system:
- Carbon monoxide - This poisonous gas reduces your blood's ability to carry oxygen around your body
- Tar - This sticky substance coats your lungs and airways, reducing their function
- Nicotine - This addictive chemical damages your respiratory surfaces
The Deadly Combination
These chemicals work together to cause serious damage to your lungs and airways, leading to reduced lung function and making you much more likely to develop respiratory diseases like lung cancer, emphysema, and bronchitis. Smoking also increases your risk of heart disease and high blood pressure.
Smoking legislation in South Africa
South Africa has implemented the Tobacco Products Control Act to protect people from the harmful effects of cigarette smoke. This important legislation aims to limit smoking habits and protect both children and non-smokers from dangerous second-hand smoke.
The main laws include:
- No smoking allowed in public places such as restaurants, schools, and offices
- No advertising or promotion of tobacco products is permitted
- Health warnings must be clearly visible on all cigarette packaging
- Nicotine and tar content must be displayed on packaging so people understand the risks
People who break these laws face heavy fines. The introduction of electronic cigarettes (e-cigarettes) has created new challenges, and ongoing research is being conducted to understand their effects on respiratory health for both users and the general public.
Artificial respiration and resuscitation (CPR)
When someone stops breathing and becomes unresponsive, they need immediate emergency help. This situation can be caused by various emergencies including heart attacks, drowning, electric shock, or choking. The person cannot breathe for themselves, so their lungs must be ventilated artificially using mouth-to-mouth resuscitation or a mechanical ventilator. Chest compressions are also essential to keep blood flowing.
Emergency CPR Procedure: The ABC Method
A - Airway: Open the airway by lifting the person's head back and tilting their chin up. This ensures air can flow into their lungs.
B - Breathing: Check if the person is breathing. If they are not breathing, begin mouth-to-mouth resuscitation to get oxygen into their lungs.
C - CPR: Start chest compressions immediately. The correct ratio is compressions followed by breaths. Continue this cycle without stopping until professional help arrives.
Critical CPR Guidelines
Remember that CPR must be performed continuously and correctly to be effective. The goal is to keep oxygen flowing to the brain and other vital organs until emergency medical services can take over. Never stop CPR once you've started - continue until professional help arrives.
Key Points to Remember:
-
Respiratory diseases are caused by three main factors: pathogens (viruses, bacteria, fungi), environmental pollutants (pollen, smoke, dust), and carcinogens (cancer-causing substances).
-
Each respiratory disease has specific characteristics: Bronchitis involves infected airways, hay fever is an allergic reaction, asthma causes airway narrowing, emphysema damages air sacs, lung cancer forms tumours, and tuberculosis is a bacterial infection.
-
Smoking is extremely harmful to your respiratory system because it contains carbon monoxide, tar, and nicotine that damage your lungs and significantly increase your risk of developing multiple respiratory diseases.
-
South Africa has strong anti-smoking laws including bans on smoking in public places, restrictions on tobacco advertising, and mandatory health warnings to protect public health.
-
CPR can save lives in respiratory emergencies - remember the ABC method: Airway (open it), Breathing (check and assist), and CPR ( compressions to breaths) until help arrives.