Difference Between ARDS and ARF

Main Difference – ARDS vs ARF

ARDS and ARF are two types of respiratory conditions which give rise to several signs and symptoms associated with breathing that are quite similar in nature. As a result, most people use these two terms interchangeably which might confuse the overall diagnosis, influencing the necessary treatment and follow-up as well. The main difference between ARDS and ARF is that ARDS (Acute respiratory distress syndrome ) is a type of respiratory failure where the lungs stiffen and lose the ability to make surfactant whereas ARF (Acute Respiratory Failure) is the inability of an individual to breath or get ventilated on their own.

This article covers,

1. What is ARDS?
     – Clinical Features, Cause, Signs and Symptoms, Diagnosis and Treatment

2. What is ARF?
     – Clinical Features, Cause, Signs and Symptoms, Diagnosis and Treatment

3. What is the Difference Between ARDS and ARF?

Difference Between ARDS and ARF - ARDS vs ARF Comparison Summary

What is ARDS

ARDS or Acute respiratory distress syndrome is a medical condition affecting the respiratory system, most often seen in critically ill patients and characterized by extensive inflammation in the lungs. Defined as a type of respiratory failure where the lungs stiffen and decrease its ability to make surfactants. ARDS often require higher levels of PEEP.

This condition can affect individuals at any age and typically progresses as a complication of severe pre-existing health illnesses such as respiratory distress, pneumonia, and sepsis.

As far as the causes for RDS is concerned, it can occur following major injury or significant irritation in the body, harming small blood vessels which perfuse the lungs. Lungs, which go out of blood supply, will be unable to function properly, resulting in ARDS.

Commonest presentation of ARDS includes difficulty in breathing, fast breathing or tachypnea and hypoxia where the level of oxygen in the blood is low. Other symptoms can be seen depending on the underlying health condition.

Major diagnostic features of ARDS

1) Diffuse, bilateral infiltration

2) Lack of evidence to point towards a diagnosed left ventricular dysfunction

3) Acute onset

Your physician will get a complete medical history followed by a thorough physical examination which will then be treated with oxygen therapy, intravenous fluids, and medicines.

Difference Between ARDS and ARF

Chest x-ray of patient with ARDS

What is ARF

ARF or Acute Respiratory Failure occurs when fluid build up and accumulate in the air sacs in the lungs, making it hard to release oxygen into the blood. Consequent results in the poor perfusion of organs with oxygen-rich blood supply will ultimately develop into acute respiratory failure.

The disorder, which can either be acute or chronic, can result in sudden signs and symptoms such as tachypnea, shortness of breath and hypoxia, and can even lead to death if not treated immediately.

Airway tract obstruction and injury to them either by trauma or foreign bodies account for the major causes of ARF. For example, when something like a peanut or coin get in your throat and blocks the airway canals, there will not be an adequate supply of oxygen into lungs, causing the poor perfusion of organs in the body.

In the same manner, injuries to the spinal cord or brain can also affect the breathing of an individual within a short period of time and immediate medical advice is needed to prevent the patient from developing fatal complications. Furthermore, injury to ribs or chest can also obstruct the breathing process, resulting in inadequate oxygen into the lungs.

Presentation of ARDS and ARF can vary according to the patient’s health condition but there will be characteristic features of difficulty in breathing, bluish discoloration or cyanosis in the skin fingertips and lips, agitation, anxiety, confusion, altered level of consciousness, rapid breathing and heart rate and profuse sweating.

Chest X-ray, ECG, Peak expiratory flow rate etc. can be used to diagnose a patient with ARF and major treatment modalities may include oxygen therapy, intravenous fluid, and mechanical support.

Main Difference - ARDS vs  ARF

Mechanical ventilator

Difference Between ARDS and ARF

ARDS is a type of respiratory failure where the lungs stiffen and lose the ability to make surfactant, therefore requiring higher levels of PEEP. However, it is important to keep in mind that not all patients with respiratory failure end up getting ARDS.

On the other hand, ARF is the inability of an individual to breath or get ventilated on their own, thus resulting in the need to an increased oxygen concentration with or without mechanical support.

Image Courtesy:

“AARDS X-ray cropped” By Samir 04:51, 17 September 2007 (UTC). Modified by Delldot 07:55, 28 April 2008 (UTC) – http://en.wikipedia.org/wiki/Image:Noncardiogenic_pulmonary_edema.JPG (CC BY-SA 3.0) via Commons Wikimedia

“VIP bird 2” By Brian Hall – Own work (Public Domain) via Commons Wikimedia

About the Author: Embogama

Embogama is a passionate freelance writer for several years. Her areas of interest include general medicine, clinical medicine, health and fitness, Ayurveda medicine, psychology, counseling and piano music