Definition and Overview

A diaphragmatic hernia is a rare medical condition characterised by the presence of an abnormal opening in the diaphragm, which causes organs in the abdomen to move up into the chest cavity.

The diaphragm is a wide, flat muscle that plays a vital role in the breathing process. It separates the thoracic cavity, which contains the lungs and heart, from the abdominal cavity. When the diaphragm contracts, it allows the volume of the thoracic cavity to increase, so air is drawn into the lungs.

A diaphragmatic hernia can be either congenital or acquired. A baby is born with the condition if his or her diaphragm and digestive tract fail to develop properly while still in the womb. A congenital diaphragmatic hernia (CDH) is life-threatening as it hinders lungs from growing to normal size. It is seen in one out of every 5,000 live births with most cases affecting the left lung.

There are two types of CHDs, namely:

  • Bochdalek hernia - The most common type of CDH that accounts for up to 90% of cases. It involves the back and side parts of the diaphragm and causes the liver, stomach, spleen, and/or the intestine to move up into the chest cavity.

  • Morgagni hernia - This type is rare, accounting for just 2% of CDH. It involves the front part of the diaphragm, which causes the liver and/or intestines to move up into the chest cavity.

An acquired diaphragmatic hernia, on the other hand, is commonly caused by physical trauma due to blunt or penetrating injuries usually caused by gunshot or stab wounds and traffic accidents. It can also be the result of accidental damage to the diaphragm during a surgical procedure involving the chest or abdomen.

Both congenital and acquired diaphragmatic hernias require immediate surgical intervention. The goal of treatment is to close the abnormal opening and return the abdominal organs into their proper position.

Causes of Condition

The diaphragm, oesophagus, stomach, and the intestines develop between the 4th and 12th week of pregnancy. A congenital diaphragmatic hernia can occur at this time if the tendon in the middle of the diaphragm does not develop properly, the intestine becomes trapped in the chest cavity, or the normal development of the diaphragm and digestive tract does not occur. Scientists believe that these abnormalities can be the result of a combination of genetic and chromosomal abnormalities, nutritional deficiencies, and environmental factors.

Key Symptoms

Most babies with CDH present with underdeveloped blood vessels in the chest and lung tissue that prevents the diaphragm muscle from functioning properly. Thus, they suffer from severe breathing problems once born. This leads to:

  • Fast heart rate

  • Lack of enough oxygen in the blood resulting in bluish colour of the skin (cyanosis)

  • Rapid breathing

Other symptoms include:

  • One side of the chest is visibly larger than the other

  • Concave abdomen

Who to See and Types of Treatments Available

A congenital diaphragmatic hernia can be diagnosed before the baby is born through a foetal ultrasound, maternal serum screening, and amniocentesis. Unborn children with CDH have bowel sounds in the chest and irregular chest movements. The test will also show that the foetus does not have breath sound on the affected side of the lung.

Careful and accurate prenatal assessment helps doctors predict the severity of CDH before birth and ensure that there are no other birth defects so appropriate treatment can be planned. The condition is often considered mild if the liver does not herniate into the chest. In such cases, any surgical procedure can be delayed until the baby is born. Meanwhile, foetuses whose liver has gone up into their chest may be candidates for prenatal intervention. The surgery’s main goals are to enlarge the affected lung and push abdominal contents out of the chest and into the abdomen. This procedure is considered high-risk, complex, and challenging. Thus, it is crucial that it is performed in a hospital that has paediatric surgery and intensive care nursery capabilities and staffed by a medical team with the needed skills, experience, and expertise.

Babies born with untreated CDH are at risk of respiratory failure due to pulmonary hypoplasia and pulmonary hypertension; two conditions that restrict blood flow through the lungs. Thus, they are admitted to the neonatal intensive care unit (NICU) right after they are born. Because they are unable to breathe properly on their own, the first step in managing their condition is securing their airway and immediately placing them on a ventilator. Often, the baby is also connected to a heart-lung bypass machine that works by circulating blood through an artificial lung back into the bloodstream. When the baby’s condition has improved, surgery to move abdominal organs that have herniated into the chest is performed. The hole in the diaphragm is also repaired either with stitches or a piece of plastic patch.

Despite successful treatment, patients often suffer from long-term problems or complications, including:

  • Chronic lung disease

  • Gastroesophageal reflux

  • Developmental delay

  • Failure to thrive

  • Hearing loss

  • Abdominal pain

  • Appendicitis

  • Constipation

  • Bowel obstruction

References:

  • What is CDH? University of California, San Francisco. https://fetus.ucsf.edu/cdh

  • Keller RL, Guevara-Gallard S, Farmer DL. Surgical disorders of the chest and airways In: Gleason CA, Devaskar SU, eds. Avery’s diseases of the newborn. 9th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 49.

  • Tsao KJ, Lally KP. Congenital diaphragmatic hernia and eventration In: Holcomb GW, Murphy JP, Ostlie DJ, eds. Ashcraft’s Pediatric Surgery. 6th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 24.

  • Logan JW, Rice HE, Goldberg RN, Cotten CM (2007). “Congenital diaphragmatic hernia: a systematic review and summary of best-evidence practice strategies”. Journal of perinatology : official journal of the California Perinatal Association. 27 (9): 535–49. PMID 17637787. doi:10.1038/sj.jp.7211794.

Share This Information: