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DISCUSSION
An incisional hernia develops in 3% to 13% of patients undergoing
celiotomy.1 The repair of these and other ventral hernias represents
a challenging surgical problem. Because primary repair with suture
alone can yield failure rates of 25% to 52%,2-4 a variety of
open techniques using prosthetic mesh have been developed. Placement
of mesh in open surgery has been shown to reduce the longterm
failure rate to 11% to 21%.2,4,9 But because open procedures
using mesh typically require extensive dissection, raising of
flaps, and drain placement, they are associated with increases
in the rates of wound complications and infections.4,6
The laparoscopic
approach to ventral hernia repair is based on the open technique
popularized by Rives and associates,17
Stoppa,4 and Wantz18.
In that procedure, a large prosthesis is placed under the rectus
muscle (external to the posterior fascia or peritoneum) to overlap
the defect by several centimeters in all directions. The laparoscopic
technique takes advantage of the concepts learned from this repair,
applies the mesh one layer deeper, and eliminates the need for
an extensive soft tissue dissection. It was theorized that if
this operation could be performed through three or four laparoscopic
trocars, there would be decreases in length of the hospital stay
and wound complication rates. Three studies
that compared laparoscopic with conventional ventral herniorrhaphy
found such decreases to be advantages of the minimally invasive
approach.9,19,20
In our series, most of the patients had good outcomes, even
though they were typically obese, had large hernias, and one-third
had previously undergone an open hernia repair. The hospital
stay averaged 1.8 days, there were no deaths, and the complication
rate was 13.0%. We observed two of the most common complications
after laparoscopic ventral hernia repair—a seroma at the
site of the hernia and suture site pain—in 2% of our patients,
a rate that appears to be consistent with those in previously
described series.14,19 It was common for short term seromas to
develop in our patients, probably because we did not use drains
and we left the hernia sac in situ. Most of these fluid collections
resolved without intervention but eight were present for more
than 6 weeks because three of the attending surgeons in the study
did not drain seromas routinely. The fourth surgeon freely aspirated
any palpable seroma. No complications resulted from aspirating
the fluid in the hernia sac or allowing it to absorb on its own.
We would recommend treating seromas in patients that are symptomatic
and allowing the others to resolve on their own.
The suture site pain that eight of our patients experienced
may have originated from tissue or nerve entrapment during placement
of the sutures through the full thickness of the abdominal wall.
We think that such suture placement is indispensable to the longterm
durability of the hernia repair and do not recommend any changes
in surgical technique to prevent pain. In our series, suture
site pain resolved without intervention over time or was treated
successfully with repeat injections of Marcaine (in two patients).
Despite our patients' complex operative histories, there was
a remarkably low number of enterotomies (six) in this series.
This result is evidence of the advantages of pneumoperitoneum
and laparoscopic adhesiolysis. The planes of dissection and attachment
are easy to see on the magnified laparoscopic image because the
omentum and viscera are suspended from the abdominal wall. In
five of the six patients in whom enterotomies occurred, the laceration
was limited (3mm to 6mm) and occurred in the small intestine
with essentially no spillage of intestinal contents. It was repaired
laparoscopically in four patients, one was converted to open,
and the herniorrhaphy was completed in each. Despite good outcomes
in this select group (ie, lack of mesh infection), surgeons should
strongly consider if inserting a foreign body in the face of
contamination is appropriate. Each case needs to be considered
individually and carefully.
The recurrence rate in our series was 3.4% during a mean followup
time of 23 months. Because approximately 66% to 90% of ventral
hernia recurrences develop within 2 years after operation,2,3
we do not expect the recurrence rate in this series to change
markedly. Most of the 14 recurrences occurred either in patients
in whom only laparoscopic tacks or staples (no sutures) were
used or in patients in whom sutures were not placed along a portion
of the mesh in sensitive areas of the body. Initially we believed
that these areas, such as the costal margin, might be apt to
generate pain if full-thickness sutures were used. The result
of not using sutures was patch migration. We believe that a strong
emphasis should be placed on appropriate fixation of the mesh
in laparoscopic hernia repair. Large, nonabsorbable sutures appear
to provide a strong and reliable fixation of the prosthesis.
Hernia tacks or staples are used to fill in gaps between sutures
but should not serve as the primary sources of attachment.
Ninety-seven percent of the hernias in this series were repaired
with ePTFE mesh. Polypropylene and polyester
mesh, two of the other most popular prosthetic materials, were
avoided because of their proved tendency to produce severe bowel
adhesions, with subsequent erosion and fistulization.4,5,7,19,21-26
Fistula rates ranging from 2% to 5% have been reported after
elective open hernia repairs in which these meshes were placed
adjacent to the bowel.7,19 Several surgeons
have recommended that these materials be separated from the intestine
if at all possible.4,7,19,23,27
Because laparoscopic ventral hernia repair entails intraperitoneal
placement of the mesh and subsequent direct contact between the
mesh and intestine, we used ePTFE in almost all patients in our
series, as has been done in nearly all other series of laparoscopic
ventral hernia repairs.8-11,13,14 The DualMesh prosthesis appears
well suited for this procedure because of its two different surfaces.
The surface that is to be exposed to the peritoneal cavity consists
of a low-porosity membrane, which does not allow extensive tissue
attachment. The other surface has an expanded microstructure,
which allows tissue ingrowth and attachment to the abdominal
wall. An additional advantage of ePTFE
is that it may be less easily infected than other biomaterials.28
We had four mesh infections in our series, but two occurred in
patients who had previously undergone open repairs and had an
infection of the mesh inserted during those procedures. Unfortunately,
ePTFE costs more than polypropylene and may be more difficult
to work with laparoscopically because of its lack of memory and
the fact that it is opaque.
As with any new operation, when a surgeon begins to perform
laparoscopic ventral or incisional hernia repairs, he or she
must use careful patient selection to establish confidence and
ensure good surgical outcomes. Initially, patients chosen for
this procedure should have small to moderately sized primary
midline hernias or recurrent umbilical defects, should not be
obese, and should not have had multiple earlier operations or
previous intraabdominal placement of mesh. As experience with
the procedure grows, many lessons are learned, key technical
challenges are identified, and operative strategies are developed.
Because of our success with laparoscopic ventral hernia repair,
we now have few contraindications to the procedure, but it should
be avoided in patients who cannot tolerate general anesthesia,
patients with strangulated intestine, and children.
Introduction
| Methods
| Results
| Discussion | References
| Commentary
JACS |
