Open In App

Respiratory System Disorders – Definition, Causes, Types, Symptoms

Last Updated : 13 Mar, 2023
Like Article

Respiration is a biological process, it involves the activity of interchanging oxygen and carbon dioxide via a liquid medium to use the oxygen for the oxidation of glucose inside the mitochondria (the powerhouse of cells) which produces the energy. Some of the energy is stored in the high-energy bonds of ATP molecules as biological useful energy. So, respiration is a physicochemical process.

Respiratory Disorders

The trachea is formed of the respiratory tract and lungs. Epidemiological, environmental, occupational, personal and social factors highly affect the respiratory system. These factors are responsible for a number of respiratory disorders which causes bitterness and early death.


It causes narrowing and inflammation of bronchi, bronchospasm and difficulty in breathing. Asthma patients take aspirin or non-steroidal anti-inflammatory drugs ( NSAID) .4 to 19 % of asthma patients develop aspirin intolerance. NSAIDs are mostly known to increase the possibility of an asthma attack. House dust, pollen grains of plants like Congress plant; drugs like aspirin; pollutants like SO2, CO2, smoke, etc. are the common allergens for asthma.

Emphysema (emphysema = inflation)                                                

  • Cause. Cigarette smoking causes emphysema which excites the liberation of proteinases and also inactivates the anti- proteinase enzymes. This declines the rebuilding capacity of injured interstitial proteins eg. Elastin.             
  • Symptoms. Emphysema shows such symptoms that is inflation of the alveoli and rupture of alveolar walls which leads to thin-walled air spaces which are called pulmonary bullae, it causes pneumothorax 
  • Precautions. Keep away from cigarette smoking.

Occupational respiratory diseases 

These diseases are caused to industrial workers due to air pollutants produced by industries eg.

  • Silicosis. This disorder gives rise to clay, sand and sandstone grinding. Irritation and fibrosis are caused by silica particles and form lumps in fibrous tissue in the lungs.
  • Asbestosis. The source of asbestosis is inhaling asbestos inside the lungs.
  • Co – poisoning. The root cause of this disease is the inhalation of CO in excess amount. Oxygen levels are decreased by carbon monoxide which causes headache, dizziness, palpitation, etc. and also leads to death.
  • Oxides of sulphur (SO2 & SO3). It causes Asphyxiation and irritation in the upper respiratory tract.


Body tissues lack oxygen. It consists of three types:-

  • Artificial hypoxia. At higher altitudes, there is a lack of oxygen in the air causing Hypoxia. It causes mountain sickness. Symptoms are headache, breathlessness, dizziness, nausea,  vomiting, and a bluish tinge on the skin and mucus membrane.
  • Anaemic hypoxia(CO – poisoning) Carbon monoxide ties haemoglobin approximately 200 times faster than oxygen to form carboxyhemoglobin. This results in declining transportation of oxygen by the blood. This gives rise to headache, dizziness, nausea, paralysis and death. Due to deficient combustion, CO is generated.
  • Histotoxic hypoxia. Cyanide poisoning. Cyanides dormant cytochrome oxidase enzyme of ETC.


Insufficiency of oxygen and accretion of CO2 in body tissues is called Asphyxia. CO2 level increases in body tissues which can paralyse the respiratory tract stop breathing and lead to death.


Corynebacterium diphtheriae bacteria causes diphtheria. Symptoms are inflammation of the respiratory tract. DPT vaccine can prevent this disorder.

Factors affecting Respiratory Disorders 

Chronic respiratory diseases ( Cards) affect the air tract and lungs. Common diseases caused due to CRD disorder are chronic obstructive pulmonary diseases ( COPD), asthma, lung cancer and pulmonary hypertension. Other factors such as tobacco smoke, air pollution, chemicals and dust. There are many treatments that can control symptoms and improve the condition.

Cause of respiratory disorders

  • Infection 
  • Smoking tobacco
  • Breathing in second-hand smoke 
  • Radon 
  • Asbestos 
  • By air pollution

Some respiratory diseases are  

  • Asthma 
  • Chronic obstructive pulmonary disease ( COPD ) 
  • Pulmonary fibrosis 
  • Pneumonia
  • Lung cancer

Lung cancer 

Mostly, people who smoke tobacco suffers from lung cancer. Lung cancer is of two types : 

  1. Non-small cell lung cancer 
  2. Small lung cancer 

Causes of lung cancer  

  • Smoking 
  • Second-hand smoke
  • Exposure to certain toxins 
  • Heredity


  • Cough 
  • Chest pain 
  • Wheezing 
  • Weight loss 
  • Shortness of breath 
  • Hoarseness 
  • Swollen lymph nodes 
  • Weakness 


  • Surgery 
  • Chemotherapy
  • Radiation therapy
  • Targeted drug therapy
  • Immunotherapy

Conceptual Questions

Question 1: Give the symptoms of respiratory disorder.


Symptoms of asthma are narrowing of bronchi due to bronchospasm. So, asthma patients feel difficulty breathing. 

Question 2: State the major difference between anaemic hypoxia and histotoxic hypoxia?


Anemic hypoxia caused due to co- poisoning of haemoglobin in the blood, whereas histotoxic hypoxia is caused due to cyanide poisoning.

Question 3: What is hypoxia?


Hypoxia is caused due to lack of oxygen in the body tissues. It is caused by mountain sickness ( due to deficiency of oxygen in the air at higher altitudes) or co- poisoning (binding carbon monoxide with hemoglobin of RBCs to prepare carboxyhemoglobin) or cyanide poisoning ( it inactivates cytochrome oxidase enzyme of ETC by cyanides ).

Question 4: Difference between Hypoxia and Asphyxia .


Hypoxia is caused due to shortage of oxygen in the body tissues, while Asphyxia is caused due to shortage of oxygen and accumulation of CO2 in the body tissues.

 Question 5: Give the scientific name of the pathogen causing Diphtheria. How is it transmitted?


A bacillus bacterium, Corynebacterium diphtheriae causes Diphtheria. It is an air-borne disease and spread through droplet infection.

Like Article
Suggest improvement
Share your thoughts in the comments

Similar Reads