3D illustration of Lungs (Respiratory System)

A Complete Guide Of The Respiratory System

Sierra Care | June 30, 2021


A Complete Guide Of The Respiratory System

Your respiratory system is responsible for every breath you take, word you speak, and scent you smell. The lungs are only one part of this complex system that is responsible for maintaining balance within your body. There are many medical conditions that can damage the respiratory system and many treatments that medical specialists use to treat patients with respiratory issues.

This article will share the basics of the respiratory system and details about the care that hospitals and facilities such as Sierra Care provide to patients that require support while recovering from a respiratory illness.

What Does the Respiratory System Do?

The respiratory system has three main functions that are critical to the body. It provides oxygen, removes carbon dioxide, and allows you to produce speech.

Supplying Oxygen

The lungs are the key part of the respiratory system, allowing the body to absorb oxygen from the air. Oxygen is one of the fuels that allow the cells of the body to function. Without oxygen the brain shuts down in seconds and the heart in two to three minutes. Each of the other parts that make up the respiratory system exists only to ensure that oxygen-filled air reaches the lungs.

Removing Carbon Dioxide

Carbon dioxide is created by the cells as they turn oxygen and glucose into energy. Similar to the exhaust from a car, if carbon dioxide is allowed to build up in the body it becomes toxic.

The amount of carbon dioxide in the body is closely controlled by the lungs, while carbon dioxide is considered harmful in large amounts it is also very important in balancing the amount of acid in the body.

  • Acidosis is the medical term for an excessive amount of acid in the body, carbon dioxide becomes an acid within the body, the lungs balance the amount of acid in the body by controlling how fast carbon dioxide is breathed out.
  • Alkalosis is the medical term for a lack of acid in the body. While acid is thought of as harmful, insufficient acid is also dangerous. This is why breathing too fast (hyperventilating) can lead to feeling lightheaded or suddenly passing out.

Creating Speech

The respiratory system also allows your larynx (the voice box) to produce speech. The vocal cords rely on air passing over them to vibrate and make the sounds that we recognize as speech. The large amount of air that can be stored in the lungs is critical to speaking in longer sentences, speaking loudly, and singing.

What Are The Major Parts of The Respiratory System?

The respiratory system is far more than just the lungs, there are several components of the respiratory system and each of these is critical to the functions that are listed above.

  • Diaphragm: Located at the base of the chest, the diaphragm moves down in response to a signal from the brain to breathe, this creates a vacuum in the chest that draws air in through the mouth.
  • Ribs and Intercostals: The ribs and intercostals (muscles surrounding the ribs) form a solid structure that supports the diaphragm and allows it to create a vacuum in the chest.
  • Oropharynx (the throat): Air from the nose and mouth meets in the oropharynx before entering the airway. This area contains structures that prevent water and food from entering the airway. Air from the nose and mouth meet in the oropharynx before entering the airway. This area contains structures that prevent water and food from entering the airway.
  • Larynx (the voicebox): The larynx contains the vocal cords that allow you to produce speech. Air moving over these cords when you exhale creates a massive variety of sounds in various tones and volumes.
  • Trachea (the windpipe): The trachea is a tube that allows air to travel from the oropharynx to the lungs. It splits into smaller passageways known as bronchi.
  • Bronchi: The bronchi are small airways that branch off of the trachea and move all throughout the lungs.
  • Alveoli: The alveoli are small sacs of air that look like grapes on a vine and are surrounded by countless small blood vessels. These vessels, known as capillaries, absorb oxygen from the air within the alveoli.

What Are Common Signs and Symptoms of Respiratory Issues

There are many medical conditions that can affect the respiratory system. These conditions have different signs and symptoms depending on what part of the respiratory system they affect.

  • Noisy breathing: A blockage of the trachea, larynx, or small bronchi can lead to noisy breathing. The most common type of noisy breathing is wheezing, which occurs when the bronchi are partially blocked. Another louder and harsher sound, stridor, occurs when the trachea or larynx is partially blocked.
  • Painful breathing: Pain with a deep breath can occur if there is an injury to the ribs, muscles, or if the lining of the lung is irritated by an infection or a blood clot.
  • Working hard to breathe: “Increased work of breathing” is a medical term that describes a patient that looks like they are trying to catch their breath even though they are not exercising. Exaggerated movement of the chest, nodding of the head, and rapid breathing are the signs of increased work of breathing.
  • Blue skin: Blue discoloration of the skin in the fingertips or around the lips is known as cyanosis; this is a sign that the body is not getting enough oxygen from the lungs.
  • Breathing too fast: Rapid breathing, known as tachypnea, can be a sign that the body is having trouble moving enough air into the lungs with each breath.
  • Breathing too slow: Slow breathing, known as bradypnea, is one of the most dangerous signs of respiratory issues. Slow breathing can lead to low levels of oxygen in the brain and the buildup of toxic carbon dioxide.
  • Fever, chills, and diaphoresis (sweating): Infections of the lungs can lead to serious illness. These symptoms are typical of any serious infection and in combination with the other signs and symptoms listed above may be a sign of a lung infection.

What Conditions Can Affect The Respiratory System?

There are many medical conditions that can reduce the ability of the respiratory system to either bring oxygen into the blood, remove carbon dioxide, or both. These conditions are very common but in some people are well controlled and cause no symptoms. In others, they may lead to potentially deadly effects.


Asthma is an inflammation of the small airways in the lungs that lead to the alveoli. This inflammation leads to swelling, which partially closes off the small airways and prevents air from easily reaching the alveoli.


COPD (Chronic Obstructive Pulmonary Disease) is very similar to asthma in that it causes the small airways to become blocked (obstruction) and once it develops cannot be fully cured (chronic).


Pneumonia is an infection of the lung tissue. There are many different bacteria, viruses, and fungus that can cause pneumonia. The most common types are atypical pneumonia, community-acquired pneumonia, and healthcare-associated pneumonia.

  • Atypical pneumonia is also known as “walking pneumonia.” The bacteria that cause this type of pneumonia rarely cause serious illness.
  • Community-acquired pneumonia is the most common form of pneumonia and typically presents with high fevers, severe fatigue, and difficulty breathing.
  • Healthcare-associated pneumonia occurs in those that have spent a large amount of time in the hospital. It can cause even more severe illness than community-acquired pneumonia and is resistant to some antibiotics.


Aspiration is the medical term for food, fluid, or vomit entering the lungs. This can block the small bronchi, fill the alveoli with fluid, or cause severe inflammation and/or pneumonia. Aspiration is common in the elderly and those who are seriously ill with other medical conditions.


A pneumothorax, commonly called “a collapsed lung,” occurs when air enters the part of the chest where the lungs are located. This prevents the lung from expanding when you breathe in, this reduces the ability of the lungs to absorb oxygen and expel carbon dioxide.

Heart failure and kidney failure

Heart failure and kidney failure do not directly affect the respiratory system. However, these conditions lead to fluid building up in the body which eventually settles in the alveoli of the lungs (pulmonary edema). This lowers the amount of oxygen that the alveoli can absorb.

What Treatments May Be Needed in Those With Respiratory Issues?


Giving additional oxygen through a mask over the face or a small tube in the nose is the most common treatment for respiratory issues. The extra oxygen can counteract the decreased ability of the lungs to absorb oxygen due to disease and allow time for the lungs to heal.


In patients with signs of an infection, especially pneumonia, antibiotics will often be given to combat the infection. This kills the bacteria that are leading to swelling and fluid accumulation in the lung and allows the lungs to heal over a few days to weeks.


Steroids are a form of hormone that lowers swelling and inflammation in the body. The lungs, bronchi, and trachea swell a significant amount in response to injury, infection, and allergens. Steroids may be taken orally or given by IV and can help with a wide variety of medical issues from mild asthma to severe pneumonia.


Certain respiratory conditions require surgery. A pneumothorax may need a surgical tube placed in the chest to drain the air accumulating in the chest. Trauma that leads to damage to any part of the respiratory system may also require surgery if the injury is leading to severe signs or symptoms.

Positive Airway Pressure

Positive airway pressure is a broad term used in healthcare that refers to forcing air into the lungs as opposed to relying on the diaphragm to pull air in naturally. Positive pressure is usually used for patients with serious respiratory issues.

  • Ventilators: A ventilator is a device that provides carefully measured positive airway pressure. A ventilator ensures that the amount of air given in a breath is large enough to supply oxygen without over-stretching the lungs and damaging them
  • Intubation: A term that refers to passing a “breathing tube” through the oropharynx and larynx. This tube seals the lungs off from the rest of the body ensuring that vomit, saliva, and fluid do not enter the lungs. Patients that are intubated require a ventilator to breathe for them.
  • Tracheostomy: A breathing tube that is placed through the neck directly into the trachea instead of through the mouth. This form of breathing tube is used in patients that will require intubation for more than 2-3 weeks. For more information read our article on tracheostomy.


Who is Involved in Treating Respiratory Issues?

The treatment of serious respiratory issues requires multiple dedicated and well-trained specialists. While some common respiratory illnesses can be treated in a doctor’s office, emergency room, or by a short stay in the hospital, other conditions can lead to weeks to months of disability that is best managed by a multidisciplinary team.

  • Nurses: As the beating heart of the healthcare team, nurses are critical to ensuring that patients are recovering and receiving the correct treatments.
  • Respiratory therapists: As specialists in the operation of ventilators and the management of patients that are intubated or living with a tracheostomy, respiratory therapists are heavily involved in the treatment of severely ill patients.
  • Physical therapists: Specialists in rehabilitation, a physical therapist leads patients in breathing exercises intended to strengthen the diaphragm, heart, and muscles throughout the body. Physical therapists treat all types of patients and are critical to returning to normal life after a serious respiratory illness.
  • Doctors: As the core of the healthcare team the doctor’s role is to review information from every member of the healthcare team and ensure that the patient has the safest and most rapid possible recovery. They also prescribe medications and follow-up with patients on a regular basis after a serious illness.

Sierra Care specializes in subacute care, the treatment of patients that have disabilities after being hospitalized for a serious illness. We employ individuals in each of the above specialties to give our patients that are recovering from severe respiratory illnesses the best possible chance of returning to a full and fulfilling life. Click here to learn more about our respiratory care services and how we can speed the recovery of you or your loved one.