Causes
The causes of umbilical hernia are congenital and acquired malformation, but an apparent third cause is really a cause of a different type, a paraumbilical hernia. Congenital
Congenital umbilical hernia is a congenital malformation of the navel (umbilicus). Among adults, it is three times more common in women than in men; among children, the ratio is roughly equal. It is also found to be more common in children of African descent. Acquired
An acquired umbilical hernia directly results from increased intra-abdominal pressure caused by obesity, heavy lifting, a long history of coughing, or multiple pregnancies. Another type of acquired umbilical hernias are incisional hernias, which are hernia developing in a scar following abdominal surgery, e.g. after insertion of laparoscopy trocars through the umbilicus. Paraumbilical
Importantly, an umbilical hernia must be distinguished from a paraumbilical hernia, which occurs in adults and involves a defect in the midline near to  the umbilicus, and from omphalocele. Diagnosis
Navels with the umbilical tip protruding past the umbilical skin ("outies") are often mistaken for umbilical hernias, which are a completely different shape. Treatment for cosmetic purposes is not necessary, unless there are health concerns such as pain, discomfort or incarceration of the hernia content. Incarceration refers to the inability to reduce the hernia back into the abdominal cavity. Prolonged incarceration can lead to tissue ischemia (strangulation) and shock when untreated. Umbilical hernias are common. With a study involving Africans, 92% of children had protrusions, 49% of adults, and 90% of pregnant women.
There are also several dissolvable packing materials that stop bleeding through use of thrombotic agents that promote blood clots, such as surgicel. The thrombogenic foams and gels do not require removal and dissolve after a few days. Posterior nasal packing can be achieved by using a Foley catheter, blowing up the balloon when it is in the back of the throat, and applying traction. Complications of nasal packing include abscesses, septal hematomas, sinusitis, and pressure necrosis. In rare cases toxic shock syndrome can occur with prolonged nasal packing. As a result, many forms of nasal packing involve use of topical antistaphylococcal antibiotic ointment. Tranexamic acid
Tranexamic acid helps promote blood clotting. For nosebleeds it can be applied to the site of bleeding, taken by mouth, or injected into a vein. Cauterization
This method involves applying a chemical such as silver nitrate to the nasal mucosa, which burns and seals off the bleeding. Eventually the nasal tissue to which the chemical is applied will undergo necrosis. This form of treatment is best for mild bleeds, especially in children, that are clearly visible. A topical anesthetic (such as lidocaine) is usually applied prior to cauterization. Silver nitrate can cause blackening of the skin due to silver sulfide deposit, though this will fade with time. Surgery
Ongoing bleeding despite good nasal packing is a surgical emergency and can be treated by endoscopic evaluation of the nasal cavity under general anesthesia to identify an elusive bleeding point or to directly ligate (tie off) the blood vessels supplying the nose.