Generality
A diaphragmatic hernia is the protrusion, due to an anomalous opening on the diaphragm, of one or more abdominal viscera in the thoracic cavity.
The opening on the diaphragm can be a congenital anomaly - therefore present from birth - or an acquired anomaly - that is, developed over a lifetime, following a specific causal event.
From the site: www.chop.edu
The symptomatic picture generally consists of respiratory disorders and consequences deriving from these. Moreover, the abdominal organs that hernian go to occupy the space reserved for the lungs, jeopardizing their growth (especially in children) and function.
To avoid complications, it is essential that diagnosis and therapy be timely; therapy which consists of an ad hoc surgical treatment, aimed at replacing the abdominal viscera and repairing the diaphragm.
What is a hernia
A hernia is the exit of a bowel and / or adjacent tissues (for example the surrounding fatty tissues) from the body cavity that normally contains them (NB: the word viscera indicates a generic internal organ).
The spill may be total or partial.
What is diaphragmatic hernia?
A diaphragmatic hernia is the escape of one or more viscera contained in the abdomen, through an anomalous opening present on the diaphragm . Therefore, these viscera protrude into the thoracic compartment, where the heart and lungs reside.
The opening on the diaphragm, which induces visceral leakage, can be a congenital anomaly - therefore present from birth - or acquired - that is, developed over a lifetime.
Especially when the subjects involved are very young children, the diaphragmatic hernia represents a medical emergency to be treated promptly, to avoid the appearance of unpleasant complications.
POSITION AND FUNCTION OF THE DIAPHRAGM?
The diaphragm is the laminar-shaped muscle, which resides on the lower edge of the rib cage and separates the thoracic cavity from the abdominal cavity.
In addition to keeping the organs of the chest separate from the organs of the abdomen, this particular laminar muscle plays a fundamental role during the breathing process:
- In the inhalation phase, it contracts, pushing the abdominal organs downwards and inducing the lifting of the ribs closest to him. This expands the volume of the chest cavity and allows the lungs to take in the necessary air.
- In the exhalation phase, it is released, allowing the abdominal organs to ascend (NB: this also occurs thanks to the support of the abdominal muscles) and to the lower ribs to return to the normal position.
At this stage, the thoracic volume is clearly reduced.
WHAT ABDOMINAL VISCERS ARE INVOLVED?
Position of the diaphragm
The abdominal viscera that can participate in the formation of a diaphragmatic hernia are: the stomach, the intestine, the spleen and the liver.
IS DIAFRAMATIC HERNIA AND IATAL HERNIA THE SAME THING?
Many people believe that diaphragmatic hernia and hiatal hernia are synonymous and that the aforementioned terms refer to the same medical condition.
However, it is not so.
The hiatal hernia, in fact, is a particular form of diaphragmatic hernia, since it consists in the specific protrusion of the stomach through the so-called esophageal diaphragmatic hiatus, that is the hole of the diaphragm in which the esophagus is usually inserted.
Causes
As can be guessed from the definition, a diaphragmatic hernia is formed due to an opening on the diaphragm .
The latter has different origins depending on whether it is congenital or acquired.
CONGENITAL DIAFRAMMATIC ERNIA
The congenital openings on the diaphragm result from an error during fetal development, which compromises the normal formation of the laminar muscle interposed between the thorax and the abdomen.
With the protrusion of one or more abdominal viscera in the thoracic compartment, the organs enclosed in the thoracic cage (lungs in particular) lack the right space to grow and develop properly. Moreover, to occupy the space reserved for them, are the organs of the abdomen that are wedged in the chest.
When the opening on the diaphragm is congenital, the diaphragmatic hernia is called the congenital diaphragmatic hernia .
Doctors have identified at least three different types of congenital diaphragmatic hernia:
- Bochdalek's hernia . It is the most common type and represents 95% of clinical cases of congenital diaphragmatic hernia. The abnormal opening on the diaphragm is located in the posterolateral corners of the aforementioned muscle. In 80-85% of patients, the posterolateral corner with the pathological opening is the left one.
- Morgagni's hernia . This type represents only 2% of clinical cases of congenital diaphragmatic hernia. The anomalous opening, from which the viscera come out, resides on the front part of the diaphragm, just behind the xiphoid process of the sternum. The exact point is in correspondence of the foramen of Morgagni (from here the name of hernia of Morgagni).
- The diaphragm elevation . It is the rarest type. It consists of a permanent elevation of a part or the whole diaphragm. This means that the abdominal organs move upwards, occupying the place reserved for the anatomical elements of the thorax (lungs in particular).
Is congenital diaphragmatic hernia the result of a genetic alteration?
Scientific studies have found that only 30% of cases of congenital diaphragmatic hernia derive from an alteration of the chromosomal outfit of patients.
For the remaining cases, the causes that cause congenital opening on the diaphragm are completely unknown. It is for this reason that doctors refer to these circumstances with the term idiopathic congenital diaphragmatic hernia, where idiopathic means the lack of a precise and identifiable triggering cause.
DIAFRAMATIC ERNIA ACQUIRED
The acquired openings on the diaphragm are generally the result of impact trauma or penetrating trauma with a seat between the thorax and the abdomen.
Impact trauma is what a motorist involved in a car accident or an individual when he falls down stairs, can participate in a contact sport, etc.
A penetrating trauma, on the other hand, is what a subject who is the victim of a stabbing or shooting is subjected to.
When the opening on the diaphragm is acquired, the diaphragmatic hernia assumes the specific name of acquired diaphragmatic hernia .
Although very rarely, it is possible that surgical incisions, performed during operations on the abdomen or chest, are responsible for penetrating injuries to the diaphragm. Therefore, in fact, even abdominal / thoracic surgery is a possible cause of acquired diaphragmatic hernia.
To be more precise, doctors indicate this particular condition with the definition of iatrogenic diaphragmatic hernia .
Epidemiology
Studies on the mortality rate of congenital diaphragmatic hernia report that the latter is lethal in 40-60% of cases. This confirms what was said in the opening of the article about the danger of diaphragmatic hernia in very young children.
Similar research, this time concerning the mortality rate of acquired diaphragmatic hernia, has shown that 17% of cases, in which the diaphragm undergoes a serious rupture, are fatal.
Symptoms and Complications
Congenital diaphragmatic hernia and acquired diaphragmatic hernia share much of the symptoms and signs.
A typical symptomatological picture includes:
- Breathing difficulties. In the presence of a congenital diaphragmatic hernia, breathing difficulties are consequent to an insufficient (or abnormal) development of the lungs ( pulmonary hypoplasia ); instead, in the presence of an acquired diaphragmatic hernia, they are the result of inadequate functioning of the lungs. In this second circumstance, the functioning of the lungs is affected by the abdominal bowel which, being in the thoracic cavity, pushes on the lungs and deprives them of the necessary space during the respiratory act.
- Cyanosis. Cyanosis is a typical consequence of an insufficient amount of oxygen in the blood. To determine the onset of this condition - which coincides with the presence of a bluish-purple color of the skin - are the breathing difficulties, described in the previous point. In fact, breathing is the act that allows the blood to "charge" itself with oxygen; oxygen that the blood carries to the various organs and tissues of the body.
- Tachypnea. It is the medical term that indicates accelerated breathing or, better, an increase in the number of breaths per minute.
- Tachycardia. It is the condition in which the resting heart rate exceeds the normal limits. In other words, it occurs when the heartbeat of the heart is accelerated.
In the case of diaphragmatic hernia (both congenital and acquired), it arises in response to breathing difficulties and the reduced presence of blood oxygen. In fact, as the heart rate increases, the blood flowing in the lungs also increases, to "charge" with oxygen. Unfortunately, in patients with diaphragmatic hernia, the lungs function poorly, so tachycardia is completely useless.
- Decrease or total absence of respiratory sounds. They are two typical signs of congenital diaphragmatic hernia, as they appear when there is an underdevelopment of the lungs (pulmonary hypoplasia).
- Perception of the classic sounds and bowel movements at the level of the thoracic area. This is typical of patients with diaphragmatic hernia characterized by the protrusion, in the thoracic cavity, of a part of the intestine.
- Perception of an emptied abdomen. It is the consequence of the fact that one or more abdominal viscera have moved into the chest.
These symptoms vary in severity in relation to the causes: the more these are severe, the more the symptoms and signs can lead to the onset of unpleasant consequences.
OTHER INJURIES ASSOCIATED WITH THE DIAFRAMMATHICIA OBTAINED
Often the acquired diaphragmatic hernia is associated with other conditions, which are also the result of impact or penetrating trauma.
These include head injuries, aortic injuries, fractures of long bones or pelvic bones, lacerations of the liver and lacerations of the spleen.
COMPLICATIONS
If not treated promptly, a diaphragmatic hernia can cause pulmonary hypertension and / or lung infections.
Diagnosis
Regarding congenital diaphragmatic hernias, doctors have the possibility to diagnose them even before birth, by means of a simple prenatal ultrasound examination ( prenatal ultrasound ). This is not surprising, because, as was said in the chapter dedicated to causes, the opening on the diaphragm is the result of an error taking place during fetal development.
Another sign of a certain diagnostic relevance (always in the case of a possible congenital diaphragmatic hernia) is the presence of a high quantity of amniotic fluid (ie the fluid that surrounds and protects the fetus, inside the uterus).
As for the acquired diaphragmatic hernias (and obviously the congenital ones not diagnosed before birth), their identification is based on the execution of different examinations and diagnostic tests. The first step consists, generally, in the objective examination ; the following in various instrumental evaluations, including: X-rays, thoraco-abdominal echography, CT of the thoraco-abdominal compartment and arterial blood gases .
EXAMINATION OBJECTIVE
During the physical examination, the doctor:
- Analyzes chest movements and assesses the presence of any anomalies
- Evaluate the presence and severity of breathing difficulties
- Consider whether the lungs produce sounds. The absence of sounds in one or both sides of the chest indicates an abnormality in one or both lungs.
- Evaluate the presence of bowel sounds or bowel movements.
- Palpate the abdomen, to see if within this there are no organs. If some organs have moved into the chest, the abdominal cavity will be less full than normal.
INSTRUMENTAL TESTS
X-rays, thoraco-abdominal ultrasound and thoraco-abdominal CT are three instrumental tests that provide fairly clear images of internal organs and tissues, allowing the doctor to observe their state of health.
Arterial blood gas analysis, on the other hand, allows an assessment of pulmonary function, the efficiency of gas exchange within the alveoli and oxygen levels circulating in the blood.
Treatment
Diaphragmatic hernia is a medical emergency that can only be cured by surgery .
When it is congenital, the ideal time for surgery is 24-48 hours after birth.
WHAT IS THE OPERATION?
The surgery involves general anesthesia, the incision of the thorax (at the point where the diaphragm resides), the relocation of the abdominal organs that have escaped into their natural cavity, the repair of the diaphragm (at the point where it presents the opening) and the closure of the thoracic incision through stitches.
Awakening from general anesthesia occurs as soon as the anesthesiologist interrupts the administration of anesthetic drugs.
SPECIAL FEATURES? OF THE TREATMENT OF CONGENITAL DIAPHRAMMATHIC HERNIA
Before any surgical operation of congenital diaphragmatic hernia, surgeons subject small patients to a medical procedure known as extracorporeal membrane oxygenation ( ECMO ).
ECMO consists of a complex device, called a membrane oxygenator, which replaces the function of the lungs and oxygenates the blood of the individual to whom the equipment is connected.
The membrane oxygenator, in fact, is made in such a way that, once connected to the patient, it collects, oxygenates and re-inserts the blood of the latter.
The connection to ECMO can last for almost all the hospitalization, as the lungs, especially in the first moments of the post-operative phase, need to rest and recover.
In fact, ECMO is equivalent to a heart-lung machine for adults.
Prognosis
Various factors influence the prognosis of a diaphragmatic hernia, including in particular:
- The degree of involvement of the lungs. If lung health is severely impaired, the patient's life is in serious danger.
- The timeliness of the treatment. A late treatment, even if the diaphragmatic hernia is not severe, can compromise the patient's health and complicate the healing process.
- The presence of traumatic lesions in other anatomical sites. This factor specifically affects the prognosis of acquired diaphragmatic hernia of traumatic origin.
According to some US statistical studies, the current survival rate for cases of congenital diaphragmatic hernia treated is over 80%.
Prevention
If the acquired diaphragmatic hernia is, in some way, preventable by acting on the risk factors, the congenital one is a condition for which there is no preventive remedy.
