HERNIA 01' THE UNIBILIC.11, CORD (HERNIA l'UNICITLI (See .Allonlinal Fissures. .11,io Knilpfelmaeller, vol. ii.) in the early embryonal period, before closure of the abdominal wall, the bowels lie as it were outside the abdominal cavity, the abdomen closing later through the two sides approaching each other. Simul taneously the relatively broad communication between the intestine and the vitelline membrane is reduced. _Vccording to _1.111feld, the absence of this reduction prevents closure owing to the persistent trac tion of the cord. The bowels, which lie as it Ivere outside the abdominal cavity, remain covered by the peritoneum and appear in the structure of the umbilical cord in the shape of a hernia. The role played by :11eckel's diverticulum probably does not differ from that of the amniotic cords in harelip. It was, of course, always found present in early dis turbance of development, and was then looked upon to explain the condition.
The anatomy accords with the history of development. The tumor varies ill size, and is situated at the umbilicus, from which it directly passes into the umbilical cord. 'rhe external covering resembles the amnion of the cord, and is transparent and macerated at various places, as if it has been present for a long time. There is a strongly vascularized line of demarcation between the amnion and the outer skin (see Spina bifida), while in other cases the skin extends like a tube over the tumor which then looks ped unculat ed. In the latter forms the hernial contents are but slight, consisting, for instance, of an intestinal loop, omentum, etc. (Fig. 32).
Underneath the amnion are remnants of the gelatine of Wharton. This covers a membrane consisting of peritoneum in those cases which have originated during a late fetal period, while in those of the umbilical cord which date from a very early disturbance it may be designated as primitive membrane (Ratlike). The latter membrane is distinguished from the peritoneum by the absence of blood-vessels.
The hernial contents consist of intestinal loops, in some cases even the liver, while very often there is a pcdunculated middle hepatic lobe (Fig. 33). In other eases there are but few intestinal loops, in a few others only a somewhat enlarged Meckel's diverticulum, giving the cord only a slightly distended appearance, so that when the cord is ligated the diverticultim may be tied off with it.
The prognosis of unoperated hernia of the umbilical cord is abso lutely unfavorable, a great number of the children dying immediately after birth from bursting of the gelatinous wall of the growth. In other cases death is soon caused from infection of the tumor walls and exten sion of the infection to the hernial contents.
Treatment.—Nothing but immediate operation can save the child, spontaneous cure by scar formation having been observed only very rarely (Sittler).
Small, pedunculated hernia: were formerly treated by subcutaneous ligature, but this is objectionable because of the danger of ligating the intestine at the same time; at any rate, the hernial sae should be opened and examined before finally tying the ligatures.
In very early eases, however, where the hernia is not excessive, I can warmly recommend Olshausen's method. An incision is made in the healthy skin around the hernia, after which the amnion, if still in a fresh and non-desiccated condition, can be easily detached from the inner membrane in the layer of Wharton's gelatine. In this way it is possible to reduce the hernia and close the skin over it without opening the peritoneum.
This, however, is possible only in small hernia., while in larger ones it is necessary, according to Lindfors, to open the hernial sac and reduce its contents. In prolapse of the liver this operation presents great difficulties, especially as the hepatic lobe is sometimes adherent to the hernial sac and the small capacity of the abdomen is unable to accom modate the intestines. If it is possible to decide that the prolapsed part of the liver is morely a middlo lobe, it may be possible to dissect it off with a Paquelin knife, thus rendering the hernia reducible (ZiElmer).
The principal rules for operation arc 1. Operate as early as possible.
2. Operate as rapidly as possible.
3. Use the simplest possible method.
The danger of infection is one of the reasons why complicated operations should be avoided, since it is impossible to disinfect thoroughly the tumor walls. The operative statistics grow worse with the age, the size of the tumor, and the quantity and kind of the hernial contents.