I Umbilical Hernia Repair Robert E. Cilley, MD, and Serene Shereef, BS ANATOMY/EMBRYOLOGY

Transcription

I Umbilical Hernia Repair Robert E. Cilley, MD, and Serene Shereef, BS ANATOMY/EMBRYOLOGY
Umbilical Hernia Repair
Robert E. Cilley, MD, and Serene Shereef, BS
n contrast to the vital role played by the umbilicus in
utero, it has minimal physiologic importance after
birth. It can be used as a convenient site for vascular
access in newborns; neonatologists use umbilical arterial
and umbilical venous catheters frequently. The umbilicus
can be a portal for infection in newborns (omphalitis).
The umbilicus is frequently used as an entry site for laparoscopic procedures. Its psychological importance
throughout life has been observed in individuals who
have had surgical loss of their umbilicus.1 Persistent umbilical hernias are the most common umbilical problem
encountered by surgeons.
I
NATURAL HISTORY
Umbilical hernias are most often noted after separation of
the umbilical cord remnant. There are no definitive prospective longitudinal studies of umbilical hernias from
birth to adulthood. It is therefore difficult to speculate as
to the natural history of this process if hernia repair is
withheld. Rupture of the hernia with evisceration is almost unheard of. Incarceration of visceral contents is
rare. Most (80%) congenital umbilical hernias close spontaneously within the first 3 years of life. However, umbilical hernias may continue to close into childhood. Hernias with a diameter greater than 1.5 cm are less likely to
close on their own. “Proboscoid” hernias that turn inferiorly as they protrude are less likely to resolve spontaneously. Umbilical hernias usually disappear abruptly when
the fascial defect can no longer admit visceral contents.
After spontaneous closure, the resultant umbilicus
usually has a natural concave appearance. Occasionally,
retained material results in a protruding umbilical stalk.
Small unrepaired umbilical hernias in girls may become
symptomatic during pregnancy when the abdominal wall
stretches. There is a greater risk of incarceration in adults
than in children.2 Although used frequently in the past,
topical applications, straps, trusses, and coins do not promote closure of the umbilical ring and may be injurious.
From the Department of Surgery, Division of Pediatric Surgery, Pennsylvania
State University College of Medicine, Hershey, PA.
Address reprint requests to Robert E. Cilley, MD, Division of Pediatric Surgery,
Milton S. Hershey Medical Center, 500 University Drive, MC H113, Hershey, PA
17033.
© 2005 Elsevier Inc. All rights reserved.
1524-153X/04/0604-0003$30.00/0
doi:10.1053/j.optechgensurg.2004.10.003
244
ANATOMY/EMBRYOLOGY
Disorders of the umbilicus are due either to the failure of
closure of the umbilical ring or because of the persistence
of structures, which usually obliterate before birth. The
formation of the umbilicus takes place in early gestation
as a result of a fusion of the body stalk containing the
umbilical vessels and allantois with the extracoelomic
yolk stalk containing the vitelline (omphalomesenteric)
duct and vessels. The fetal midgut normally returns to the
abdominal cavity by 12 weeks’ gestation, and the abdominal wall closes. The umbilicus closes as mesoderm migrates in to form the abdominal wall. Failure of this closure can lead to an omphalocele, hernia of the umbilical
cord, or an umbilical hernia. An umbilical hernia is distinguished from a “hernia of the umbilical cord.” A hernia
of the umbilical cord is similar to an omphalocele in that
there is a defect in the peritoneum as well as a fascial
defect and the viscera herniate into the substance of the
cord itself. In a true umbilical hernia, the hernia protrusion is composed of peritoneum adherent to the undersurface of the umbilical skin.
The umbilical ring continues to close until birth as the
linea alba narrows and the rectus muscles approach the
midline. At birth, the contracted umbilical ring is normally reinforced by the round ligament (umbilical vein),
urachus, lateral umbilical ligaments (vestigial umbilical
arteries), and Richet’s umbilical fascia (a subumbilical
extension of transversalis fascia). Incomplete development, imperfect attachment, or weak areas in either ligamentous or fascial structures may predispose to herniation at the umbilicus. The defect is usually noticed within
a few days or weeks after separation of the cord.3 As noted
above, the process of umbilical ring closure can continue
after birth for months or even years.
INCIDENCE
The true incidence of umbilical hernia is unknown because
most umbilical hernias resolve spontaneously. Race and prematurity are predisposing factors with umbilical hernias
found more commonly in children of African descent. The
incidence of umbilical hernias decreases with advancing age.
There is a high familial incidence, but no genetic pattern of
inheritance has been identified. Umbilical hernia is commonly associated with a number of congenital malformations including thyroid dysgenesis, trisomy 18, trisomy 13,
Operative Techniques in General Surgery, Vol 6, No 4 (December), 2004: pp 244-252
245
Umbilical Hernia Repair
trisomy 21, Beckwith-Wiedemann syndrome, and Hurler
syndrome.1
SURGICAL INDICATIONS
An umbilical hernia may cause considerable parental anxiety and often results in requests for operative repair in
early infancy. Because most umbilical hernias will decrease in size and close spontaneously, parents can be
reassured and operation avoided in most children.4 Parents should be reminded not to apply straps, trusses, or
coins to promote closure. Parents may associate abdominal pain and colic with the presence of an umbilical hernia, however, an umbilical hernia rarely causes pain.
Incarceration and strangulation are absolute indications for surgical repair. If incarceration occurs, it can
usually be reduced manually and the hernia repaired electively.1 Sedation may aid reduction of the hernia. Rupture
and evisceration, although extremely rare, require immediate operation. Persistence of the hernia is the most common reason for operation. If the hernia persists as the
child approaches school age (4-5 years of age), repair is
recommended. Earlier repair (at age 2-3 years) is warranted if there is no reduction in the size of the hernia
defect with serial observations. Fascial defects greater
than 2.0 cm and “giant proboscoid hernias” should also
be considered for earlier repair.
PERIOPERATIVE CARE
No preoperative testing is required in healthy children.
Before the procedure, the child is kept without oral intake
according to age and local pediatric anesthetic practices.
Operative repair is performed as an outpatient procedure
under general anesthesia. Local anesthetic infiltration,
paraumbilical block, or a caudal epidural block can be
used to minimize postoperative pain.2 Local/regional anesthetic administration before the incision may be more
beneficial than at the time of closure. Oral analgesics are
given in the early postoperative period before the local
anesthesia wears off. Acetaminophen with codeine may
be used for pain control for 24 to 48 hours. Postoperatively oral fluids can be offered when the patient is fully
awake and alert.
246
Cilley and Shereef
SURGICAL TECHNIQUE
1
The incision. After appropriate skin preparation and application of sterile drapes, a curvilinear incision is marked in a natural
skin crease within or immediately below the umbilicus. The incision can often be hidden along or within the lower umbilical fold
and need not be placed conspicuously on the abdominal wall skin. Grasping the redundant umbilical skin and applying traction to
the abdominal wall facilitates the incision. The curved incision should not extend beyond 180°.
Umbilical Hernia Repair
2
247
Dissection of the hernia sac. The subcutaneous tissue is incised and bleeding points controlled with fine tip electrocautery. A
dissection plane is present between the subcutaneous fat and the hernia sac that leads to the fascial ring at the level of the abdominal
wall. Any contents in the sac are reduced into the peritoneal cavity. With upward traction on the inner margin of the upper edge of
the incision, dissection is performed in this plane along the sac to the level of the anterior abdominal wall fascia. The sac is dissected
circumferentially by blunt dissection with a fine clamp. The plane of dissection is developed superiorly on either side of the sac until
the sac is encircled. The sac is either transected or detached from the under-surface of the umbilical skin. It is important to avoid
fenestration of the skin at the base of the umbilicus. The dissection of the hernia sac is extended into the plane between the
abdominal wall fascia and the subcutaneous tissue of the abdominal wall for a variable distance. The dissection is limited to the
minimum distance that allows closure of the fascia without distortion of the periumbilical skin.
248
3
Cilley and Shereef
Repair of the defect. (A) The hernia sac is elevated, opened (if not already done) and inspected. Occasionally other umbilical
abnormalities will be encountered such as urachal remnants or omphalomesenteric remnants and should be excised/repaired.
Umbilical Hernia Repair
3
(B) The rim of the defect is identified and the sac incised to allow placement of sutures starting at one corner.
249
250
3
Cilley and Shereef
(C) The remainder of the sac is excised and fascial sutures placed sequentially until the entire defect is controlled. Sutures are
not initially tied to maintain control of the edge of the defect and avoid visceral injury. All of the sutures are then tied. Suture
material may be either absorbable or nonabsorbable and is chosen according to the size of the patient (3-0 for infants and young
children, 2-0 for older children and teenagers).
251
Umbilical Hernia Repair
4
Simple umbilicoplasty. The
umbilicus is maintained in inversion
by placement of sutures between the
dermis and the fascial closure. The
undersurface of the redundant umbilical skin is tacked to the anterior
abdominal wall fascia with one or
two interrupted 4-0 absorbable
sutures.
5
Closure. A running fine absorbable suture is used to close the dermis. Skin sutures that require removal are avoided. Many pediatric
surgeons use flexible collodion to
dress the skin.5 A pressure dressing
is applied and left in place for several
days to prevent a wound hematoma.
252
Cilley and Shereef
DISCUSSION
Complications are uncommon, but wound hematoma
and wound infection (1%) occasionally occur.4 Recurrence is rare. Wound infection makes recurrence more
likely. The umbilicus may not have a perfectly natural
appearance after operation and some patients are dissatisfied with the appearance. Supra-umbilical, epigastric
hernias may occur alone or in conjunction with an umbilical hernia and should be repaired concurrently. A supra-umbilical incision allows both defects to be repaired.
It is interesting to note that there is a wide range of
technical variation in an operation that is performed so
commonly. Some of the common technical alternatives
are discussed below.
1. Closure of the fascia: The fascial closure can be
performed using a closed technique. The sac is sharply
detached from the umbilicus and inverted. The fascia
edges are approximated without entry into the peritoneum and the sac is never opened. The dermis underlying
the center of the umbilicus is secured to the fascia to
restore the normal umbilical contour.
2. The distal sac can be left on the undersurface of
umbilical skin.
3. A two-layer closure of the fascia may be performed
either by imbricating the initial suture line or by overlapping the edges of the fascia.
4. Fascia may be closed in either a horizontal or a
transverse fashion. Either absorbable or nonabsorbable
suture material may be used.
5. The operation can be performed through the base of
the umbilicus rather than through the traditional curvilinear incision below the umbilicus. A supraumbilical
incision is also acceptable.
6. Excess or redundant skin can simply be ignored and
the base of the umbilicus tacked to the fascia. The natural
history of such repairs is unknown. Redundant skin can
also be excised and a formal umbilicoplasty performed
using a variety of techniques. These techniques are particularly useful in the case of a large proboscoid hernia.
The true outcomes of umbilical hernia repair have not
been studied in a long-term, prospective manner. It is not
known whether any of the technical variations listed
above result in fewer complications or improved longterm appearance.
REFERENCES
1. Cilley RE, Krummel TM: Disorders of the Umbilicus, in O’Neill JA,
Rowe MI, Grosfeld JL, et al (eds): Pediatric Surgery (ed 5, vol 2).
Baltimore, MD, Mosby, 1998, pp 1029-1043
2. Garcia VF: Umbilical, other abdominal wall hernias, in Ashcraft KW, Murphy JP, Sharp RJ, et al (eds): Pediatric Surgery
(ed 3). Philadelphia, PA, W.B. Saunders Company, 2000, pp
651-653
3. Shaw A: Disorders of the umbilicus, in Welch KJ, Randolph JG,
Ravitch MM, et al (eds): Pediatric Surgery (ed 4, vol 2). Chicago, IL,
Year Book Medical Publishers, Inc, 1986, pp 731-739
4. Grosfeld JL: Hernias in children, in Spitz L, Coran AG (eds): Rob &
Smith’s Operative Surgery. Pediatric Surgery (ed 5). New York, NY,
Chapman & Hall Medical, Lippincott Williams & Wilkins, 1995,
pp 232-236
5. Singh G: Technical Bulletin, Collodion: http://surgery.psu.edu