Humans have to source oxygen from the environmental air in order to survive. First air has to be drawn into the body until the oxygen can be extracted in the lungs. Then the air with carbon dioxide added to it from within the body is passed out into the environment. This is a simple concept that we all understand. However, we do not always appreciate the number of problems that can arise while the air flows in and out of the lungs.
When we say that we are finding it hard to breathe we are actually referring to dyspnea. This is the medical term for difficulty breathing, including shortness of breath and labored breathing. Sometimes there is no actual problem with breathing or the respiratory system although it feels like so. This may be due to high carbon dioxide levels in the blood or when the heart cannot circulate blood properly.
Airflow from Environment to Lungs
During inhalation (inspiration) we draw air in though the nostrils into the nasal cavity. Sometimes we are forced to breathe through our mouth but this is not the ideal route for regular breathing. Once the air is in the nose, it is slowed and warmed by turbinate bones in the nasal cavity. The air then passes down the nasopharynx (nose-throat juntion) into the throat (pharynx) and then into the larynx (voice box). From here it travels into the trachea (windpipe) which then divides into the two bronchi (singular ~ bronchus).
The bronchi then divide into many more smaller channels known as bronchioles until the air is delivered to clusters of air sacs in the lungs. From the nose right through down to the smallest bronchioles (terminal bronchioles) the air is further warmed and tiny hairs (cilia) and mucus traps any dust or other particles before it can reach the lungs. Air that is exhaled (expiration) has to travel the same course until it is passed out into the environment through the mouth or nose.
Causes of Hard Breathing
Dyspnea that is caused by a nose, throat and/or lower airway problem is usually due to an obstruction along the path that the air flows. However, there are times where the problem lies just outside of the air passages and lungs which affects normal respiratory movements for drawing in and pushing out air.
These are a number of nasal conditions that can impair air flow through the cavity. It does not pose as much as a problem as an impediment in the throat or lower airways since the mouth is the alternate pathway for airflow. Most of the nasal conditions that can contribute to the sensation of feeling it hard to breathe is a result of mucus collection leading to nasal congestion.
- Rhinitis means inflammation of the nasal cavity. The inner mucus-producing lining becomes inflamed and there is excessive amounts of mucus then congest the nasal passages. Viral infections and allergies are come of the common causes.
- Sinusitis refers to inflammation of the paranasal sinuses. The mucus production within the sinuses drain in to the nasal cavity and when excessive it can cause nasal congestion. Bacterial, fungal and viral infections as well as allergies are some of the causes.
- Nasal polyps are benign growths that protrude from the inner nasal lining. It is caused by recurrent infections, chronic inflammation associated with allergies and certain immune disorders.
- Deviated septum is a displacement of the thin bone that divides the nose into the left and right side. It should lie very close to the middle but can sometimes shift more towards one side and impair air flow through that side.
The throat is a much large channel than the nose and air flow is not usually restricted significantly in mild conditions.
- Pharyngitis is inflammation of the throat. Often the tonsils are also inflamed (tonsillitis) and collectively these conditions are referred to as tonsillopharyngitis. Most of us simply call it a sore throat. It is mainly due to an infection especially in children and chronic cases particularly in adults is often due to gastroesophageal reflux disease (GERD).
- Epiglottitis is a condition where the epiglottis is inflamed. The epiglottis is a small flap that closes the airways when swallowing food or drink. Epiglottitis is usually caused by upper respiratory tract infections (URTIs) and is continuous with pharyngitis and/or laryngitis.
- Laryngitis is inflammation of the larynx, the part of the throat where the vocal cords are located. It is also referred to as the voice box. Most cases are due to infections like with pertussis (whooping cough). A hoarse, raspy voice and sometimes voice loss are common symptoms.
Lower airway conditions that impairs breathing is often described as chest problems since this is where these structures are located.
- Tracheitis is inflammation of the trachea (windpipe) which is most of the time due to a bacterial infection. It is mainly seen in young children and usually arises after a viral infection of the upper respiratory tract.
- Asthma is a condition where the bronchi become inflamed with exposure to certain triggers and also constrict (broncospasm). It usually arises in childhood and is often linked to allergies. Exercise, psychological stress and airbone triggers like pollen can be a problem.
- Bronchitis is inflammation of the bronchi that usually arises with an infection. The swelling of the bronchi walls and the excessive mucus leads to narrowing and restricted airflow. Chronic cases are often associated with long term cigarette smoking.
- Bronchiectasis is a condition where the airways widen due to damage and scarring. As a result the airways cannot clear mucus effectively which then increases the risk of infections. Bronchiectasis is caused by repeated infections.
Other chest problems like flail chest, pneumothorax or hemothorax and diaphragm dysfunction can all affect respiration and make it hard to breathe. Furthermore the rate and depth of breathing is controlled by the central nervous system. Any problem of the CNS may be incorrectly perceived as a chest problem. The same applies to cardiovascular, blood and kidney disorders that can compromise the transport of oxygen or removal of carbon dioxide from the bloodstream.