Diaphragm

Overview

What is the diaphragm?

The diaphragm is a muscle that helps you inhale and exhale (breathe in and out). This thin, dome-shaped muscle sits below your lungs and heart. It’s attached to your sternum (a bone in the middle of your chest), the bottom of your rib cage and your spine. Your diaphragm separates your chest from your abdominal cavity (belly).

In addition to helping you breathe, your diaphragm increases pressure inside your abdomen. This helps with other important functions, such as getting rid of your urine (pee) and feces (poop). It helps prevent acid reflux by putting pressure on your esophagus (food tube in your throat). Your esophagus and several nerves and blood vessels run through openings in the diaphragm.

Many different conditions can affect how the diaphragm works. The most common conditions include hernias and nerve damage from surgery or an accident. Neuromuscular disorders such as amyotrophic lateral sclerosis (ALS) can also weaken the diaphragm. These conditions can cause difficulty breathing, heartburn and pain in the chest and belly.

Function

What does the diaphragm do?

The diaphragm plays a critical role in the respiratory system. When you breathe in, your diaphragm contracts (tightens) and flattens, moving down towards your abdomen. This movement creates a vacuum in your chest, allowing your chest to expand (get bigger) and pull in air. When you breathe out, your diaphragm relaxes and curves back up as your lungs push the air out.

Several nerves, soft tissues and blood vessels pass through the diaphragm. These include the:

  • Aorta, a big artery that carries your blood away from your heart to the rest of your body.
  • Esophagus, a hollow tube that connects the throat to the stomach. Food and liquids move through the esophagus to the stomach.
  • Inferior vena cava, a vein that carries blood to your heart.
  • Phrenic nerve, which controls the diaphragm’s movement.
  • Thoracic duct, a vessel that carries a fluid called lymph through the body as part of the lymphatic system.
  • Vagus nerve, which has many important jobs, including helping to control the digestive system.

Conditions and Disorders

What conditions and disorders affect this system?

Many conditions, diseases and injuries can affect the diaphragm, including:

  • Hernias: A hiatal hernia happens when the top part of your stomach bulges through an opening in the diaphragm. A diaphragmatic hernia occurs when an organ in your abdomen bulges into the chest cavity. These hernias can be present at birth or they can result from trauma, age and obesity. Hernias may require surgical repair.
  • Phrenic nerve damage: Nerve damage can result from cancer, autoimmune diseases or trauma. It can also happen during surgery including heart bypass surgery and lung transplants. A tumor, aortic aneurysm or cervical spondylosis can compress or damage the nerve. Conditions such as HIV and diseases like West Nile virus and Lyme disease can cause the nerve to become inflamed (swollen).
  • Spasms: During a diaphragm muscle spasm, the diaphragm doesn’t relax and curve back up when you exhale. It contracts (tightens), causing a cramp in the abdomen. Strenuous exercise can cause this type of spasm, which some people call a “side stitch.” It usually gets better with rest.
  • Weakness or paralysis: Neuromuscular disorders can cause diaphragmatic palsy (weakness of the diaphragm muscle). These may include multiple sclerosis (MS) and ALS. The diaphragm can also weaken as a result of diabetic neuropathy, spinal cord injuries or lung issues like chronic obstructive pulmonary disease (COPD).

What are the symptoms of diaphragm problems?

Symptoms of diaphragm problems may only last a short time, or they may be permanent. They include:

  • Acid reflux, heartburn, cough and difficulty swallowing.
  • Changes in skin color (skin may turn blue).
  • Fast heart rate, chest pain and tightness or trouble breathing (especially when lying down).
  • Headaches.
  • Hiccups that don’t go away or come back often.
  • Pain or pressure in the chest, back, side, shoulder or abdomen (usually under the lower rib cage). Belly, chest and back pain might be worse after eating.
  • Pulsing or fluttering in the belly under your ribs.

Some signs of diaphragm problems are similar to symptoms of a heart attack. If you have shortness of breath, chest tightness or chest pain, get immediate medical help.

How common are these conditions?

Phrenic nerve damage from trauma (either through surgery or an accident) is the most common cause of diaphragm problems. The risk of phrenic nerve damage (and muscle weakness) after cardiac bypass surgery may be as high as 20%.

Hiatal hernias are common, especially in people over 50 who are obese. About 55% of people over 50 have a hiatal hernia.

Care

How can I keep my diaphragm healthy?

Your diaphragm is a muscle. Just like any other muscle in your body, you can strengthen it with exercises. Diaphragmatic breathing exercises can help your diaphragm work more efficiently. They also reduce stress and help you feel better.

To keep your diaphragm healthy, you should:

  • Eat smaller meals and avoid foods that cause heartburn.
  • Get regular checkups if you have a condition that puts you at a higher risk of diaphragm problems.
  • Maintain a healthy weight.
  • Warm up before you exercise to allow your diaphragm time to stretch. Don’t overdo it when exercising.

Frequently Asked Questions

When should I call my doctor?

If you have any symptoms of diaphragm problems, see your provider. Some symptoms are similar to signs of a heart attack. Get immediate medical help if you have chest pain or pressure or shortness of breath.

Symptoms of diaphragm problems may also be signs of other conditions. It’s essential to see your provider for an evaluation.

How do I know if I’m at risk for diaphragm problems?

You have a higher risk of developing problems with your diaphragm if you have:

  • Autoimmune disorders such as lupus.
  • COPD, lung cancer or other lung problems.
  • Heart disease that requires surgery.
  • Lyme disease.
  • Neuromuscular disorders such as MS.
  • Obesity.
  • Viruses, including HIV.

A note from Cleveland Clinic

Your diaphragm plays a critical role in helping you breathe and keeping you healthy. Several conditions, diseases and injuries can damage the diaphragm. If you have a condition that puts you at a higher risk of diaphragm problems, talk to your provider about getting regular checkups. Get help right away if you have shortness of breath, chest pain or difficulty swallowing. You can strengthen this important muscle with special breathing exercises. These exercises help your diaphragm work as it should.

Reviewed by a Cleveland Clinic medical professional.

References

  • Kokatnur L, Vashisht R, Rudrappa M. Diaphragm Disorders. [Updated 2020 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. https://www.ncbi.nlm.nih.gov/books/NBK470172/ (https://www.ncbi.nlm.nih.gov/books/NBK470172/) Accessed 3/24/2021.
  • Merck Manual (Consumer Version). Control of Breathing. https://www.merckmanuals.com/home/lung-and-airway-disorders/biology-of-the-lungs-and-airways/control-of-breathing (https://www.merckmanuals.com/home/lung-and-airway-disorders/biology-of-the-lungs-and-airways/control-of-breathing) Accessed 3/24/2021.
  • National Heart, Lung, and Blood Institute. How the Lungs Work. https://www.nhlbi.nih.gov/health-topics/how-lungs-work (https://www.nhlbi.nih.gov/health-topics/how-lungs-work) Accessed 3/24/2021.
  • Smith RE, Shahjehan RD. Hiatal Hernia. [Updated 2020 Sep 1]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. https://www.ncbi.nlm.nih.gov/books/NBK562200/ (https://www.ncbi.nlm.nih.gov/books/NBK562200/) Accessed 4/1/2021.

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