Abdominal hernias are one of the most common surgical problems. By definition, a hernia is an abnormal protrusion from one anatomic space to another, with the protruded parts generally contained in a saclike structure formed by the membrane that naturally lines the cavity. They are a one of the leading causes of morbidity and can be lethal.
There are a number of different abdominal hernias and they are classified by their anatomical locations:
The hernias may also be classified as congenital such as an indirect inguinal hernia or acquired .
The congenital hernias are caused by small defects that occur during embryogenesis. Acquired hernias are caused by an increase in the abdominal cavity pressure that may weaken the wall and cause the protrusion. Risk factors for this include ascites, weight lifting, coughing, peritoneal dialysis and obesity  .
As many as 10 to 13% of people will have a hernia at one time in their life. The most common hernia being inguinal taking up about 75% of all hernias of which 50% are indirect, 14% are umbilical, 10% are ventral and 3 to 5% femoral . Inguinal hernias are more common in males, with 25% of males having one in their life time.
This is dependent on the type of hernia present and its size and location. The largest risk is strangulation of intestines and if not repaired in time, it may lead to mortality rates as high as 10%. Uncomplicated hernias have a good prognosis if repaired appropriately .
The hernia presents as a protrusion that gets bigger with increased intraabdominal pressure such as during coughing. They patient may present in an emergency situation with a strangulated hernia, or it may be found on routine examination. The protrusion may be intermittent or constant.
If strangulated, there is pain, swelling and erythema at the hernia site. There may be associated symptoms of intestinal obstruction like abdominal pain, vomiting and nausea. There may be peritonitis if the bowel gets gangrenous and perforates .
There are no specific laboratory studies specific for hernia, but they may help in toxic patients.
CT scan, ultrasound and radiographs are not usually required but may be used to confirm the diagnosis if there is doubt. The bulk of the diagnosis is clinical. In acquired hernias, workup of the underlying cause will have to be searched for, for example ascites .
In adults most hernias should be repaired to prevent complications. Reduction should be avoided if there are signs of inflammation or strangulation. Usually all inguinal hernias should be repaired. Umbilical hernia repair should be carried out in adults. In children most will close by the age of five, unless they are large. Elective repair is preferred to acute repair. There are number of methods that can be used, for example the use of meshes and special suturing techniques.
There is no prevention of congenital hernias. Avoidance of chronic increased intraabdominal pressure is key. Thus patients with the risk factors for this should be treated promptly and appropriately  .
The internal organs are held in a cavity with a wall (abdominal). Defects in the wall may cause protrusion of the contents of the cavity. This causes a visible bulge in the defect. There many different types of abdominal wall hernias. The most common being inguinal hernia, which are more common in men. These occur around the groin area.
They are two types; defects in the wall that you are born with, so when the pressure in the abdomen increases the contents are pushed through this defect. The second are caused by having conditions that weaken the abdominal wall and increase the pressure within, like a chronic cough, or chronic straining while urination.
These may present as a bulge in the trunk of the body that increases in size on coughing or straining. The protrusion may balloon out into a sac that may hold intestines. The intestines may get jammed up in the sac and swollen and compressed. This is an emergency and can be fatal.
Hernias are diagnosed by your doctor just by examination, the doctor may order some scans, but this is not routinely done.
Hernias are repaired by surgery. There are two ways this may be done. Open surgery and laparoscopic or keyhole surgery. This will depend on the size and location of the hernia. They may also use meshes to strengthen the defect in the wall to prevent it coming back again.