Laparoscopic repair of inguinal hernias almost always implies the placement of a reinforcing mesh prosthesis in the pre-peritoneal space , in accordance with the open operation described by Stoppa in 1967.
The laparoscopic route used was the totally pre-peritoneal (TPP) approach which most closely resembles the Stoppa technique.
Given that it is only the surgical approach that differs, we felt it useful to undertake a prospective randomized study comparing the two techniques.
Type III: Posterior wall defects:
A- Direct inguinal hernias.
B- Large indirect inguinal hernias.
C- Femoral hernias.
Type IV: Recurrent hernias
– Inclusion criteria
Inguinal hernias, direct or indirect hernias (Nyhus III A-III B), primary or recurrent hernias (Nyhus IV), in males greater than 40 years of age.
– Exclusion criteria
Femoral hernias (Nyhus III C), female patients, irreducible or strangulated hernias, recurrent hernias following mesh repair and large inguino-scrotal hernias.
Contraindications for general anaesthesia and laparoscopy: age greater than 75 years, poor cardio-respiratory status, cirrhosis, coagulopathies (including thrombocytopaenia), glaucoma.
Previous history of lower midline abdominal incision (excluding appen- dicectomies), abdominal wall or groin infections or pelvic irradiation.
Morbid obesity (BMP > 30).
a- Stoppa operation .
Extra peritoneal approach via a lower midline incision:
Dissection of the preperitoneal space from one psoas muscle to the other.
Placement of a dacron (Ethicon) mesh (30 x 15 cm) with its lower edge slit to allow passage of the spermatic cord.
Mesh not fixed.
b- “Laparoscopic” repair. Totally preperitoneal approach (TPP) using direct co-inflation of the cave of Retzius via a Veress Needle, and placement through 3 or 4 ports, of one or (in the case of bilateral hernias) two pieces of polypropylene mesh (Ethicon) slit at the lower edge and not fixed: (11 x 6 cm at the start of the study, later 15 x 13 cm, following an early recurrence (in the eleventh patient).
c- Common features.
Antibiotic prophylaxis using a 1 g intravenous bolus of Cloxacilline® (Beecham, Nanterre, France) on induction.
Anti-thrombosis prophylaxis with subcutaneous low molecular weight heparin (Calcium Nadroparine®- Sanofi, Gentilly, France) commenced pre operatively at a dosage of 0.3 ml once a day.
Preparation of the operative site with chlorhexidine® 0-5% (Zeneca Pharma, Cergy, France).
Decision to drain left to the discretion of the surgeon.
From July 1991 to March 1995, 100 patients were selected prospectively according to the above criteria. Informed consent was obtained by written agreement between the interested parties.
Patients with hernias of Nyhus types
A, III В, IV were allocated to either of the two operative groups using random number tables.
Before beginning the study, the laparoscopic (TPP) operation was performed on 50 patients, not included in the series. This was to confirm the feasibility of the operation and serve as a training period for the four members of the surgical team.
Results were expressed as mean values with standard deviations. The two groups were compared using, the non-parametric Mann-Witney test as well as Chi and Student’s-1 tests.
– Outcomes for comparison
Mortality and morbidity: wound infection, urinary infection, lymphangitis, general medical conditions.
Length of operation, hospitalisation and time off work.
Evaluation of recurrence rates constituted the principal criterion for comparison. All patients were seen at one month by their operating surgeon. Long term follow-up consisted of six monthly reviews by a surgeon independent of the protocol.
Evaluation of post operative comfort.
Post operative pain was assessed by means of a verbal scale comprising a list of words from which the patient selected one or more to best describe his pain and to which he attributed a coefficient as a function of intensity. The coefficients were then added to give a total score.
A visual scale, consisting of a line extending from left (no pain) to right (unbearable pain) on which the patient noted the intensity of pain experienced. The distance along the line was thus used to give a score from 0 to 10.
Analgesic consumption: Paracetamol® (UPSA, Rueil Malmaison, France) at a dosage of 1 gram up to 4 times a day was made freely available, thus permitting the evaluation of daily consumption by each group.
Direct (Nyhus IIIA) 36 39
Indirect (Nyhus IIIB) 15 10
Bilateral 21 24
Recurrent (Nyhus IV) 20 23
– Mortality and morbidity
There were no deaths in either group. Morbidity was significantly less after laparoscopic surgery: two cases (4%) versus eleven cases (29.5%) for the open method . In this latter group, five cases were related to the abdominal wall (two wound infections, two haematomas, one dehiscence), three to urinary problems and three to general medical conditions.
– Length of hospital stay (Table 3)
Regardless of the type of hernia, this was significantly shorter after laparoscopic surgery (3.2 days), representing an improvement of some 60% when compared to the Stoppa operation. In the latter group, the length of stay for patients suffering a complication was indeed longer (8.7 days) but this was not actually significant when compared to uncomplicated cases (7.3 days).
– Post operative pain
This was significantly greater for patients in the Stoppa group.
The verbal scale index was threefold higher with respect to the laparoscopic group on day one and fourfold on days 2 and 3 .
The visual scale index was increased threefold on day one, fivefold on day 2 and sixfold on day 3 .
Paracetamol consumption was also significantly greater in the Stoppa group by factors of 3.1,6 and 20 on days
and 3 respectively .
These data lead us to conclude that post operative pain and analgesic consumption was less after laparoscopic surgery. Patients in the Stoppa group experienced more pain, despite greater use of paracetamol. These pain levels were independent of morbidity.
– Return to work
Of the 40 patients in regular employment (28 in office and 12 manual labour), 21 were treated laparoscopically and 19 by the Stoppa operation. Return to work was significantly earlier after laparoscopy (17 ± 11 days vs 35 ± 14 days), regardless of the type of work.
The rate of follow up was 97% at one year, 95% at two years, and 93% at three years. The mean duration was comparable in both groups (570 days for laparoscopy and 610 days for Stoppa) with extremes of 30 and 1600 days.
There were three recurrences (6%) in the laparoscopic group and one (2%) in the Stoppa group (ns). The recurrences in the laparoscopic group all occurred at the outset of the study . They were first noted at two, four, seven months respectively and could be attributed in each case to a mesh which was too small (11 x 6 cm, not fixed) and not tailored to the surface to be covered. Since the routine use of the larger (15 x 12 cm) mesh no further recurrences have been detected.
The laparoscopic approach to inguinal hernias is based on the same principle. After dissection of the sac and spermatic cord, it is routine to place a mesh in the pre-peritoneal space in order to occlude the deep inguinal ring.
Two basic techniques can be used: The intra peritoneal approach involves the creation of a pneumo-peritoneum with its implicit risks of visceral and vascular injuries related to insufflation and trocar insertion. It also requires the fixation to Cooper’s ligament of a polypropylene mesh which according to those who regularly use this method, should be as large as possible . This technique may result in specific complications related to difficulties in closing the peritoneum , such as incarceration of a loop of small bowel and secondary intestinal lesions caused by adhesion to the prosthesis. Its principal advantage however is the improved exposure and visualisation of all possible hernia sites. By contrast, the totally pre-peritoneal route most closely resembles the Stoppa technique and would therefore seem to us to be optimal. All of its technical aspects have been standardised with the exception of problems relating to parietalisation and mesh fixation. Apart from the cost of automatic staplers, stapling per se may lead to neural and vascular complications and rarely but nonetheless importantly, to pubic osteitis.
Fashioning a slit for the cord as we have described in reproducing Stoppa’s technique effectively anchors the mesh and obviates the need for staple fixation.
Whichever method is used and despite the large numbers in some series, long-term follow-up remains inadequate for assessment of effectiveness.
Until now few controlled studies have been reported. Although differing widely with regard to the techniques compared they have all tended to produce results in favour of laparoscopic treatment. Post-operative recovery has been shorter and less painful and the resumption of work and leisure activities more rapid.
Kunz in a series of 70 patients, compared the intra-peritoneal laparoscopic method with the Shouldice repair and found the former to have no significant benefit other than improved comfort in the first post operative week and a greater degree of satisfaction at one month.
In 1994 we reported the preliminary results of a controlled trial of 181 patients (ongoing study) comparing the totally pre-peritoneal approach to the Shouldice method. Once again there was no apparent difference between the two groups (even with respect to recurrences at an average follow up interval of 15 months) other than a better quality of life in the immediate post-operative period.
Stocker’s study of 75 patients compared two groups of patients treated by the intra-peritoneal laparoscopic method and Lichtenstein’s operation . Analgesic consumption was less in the laparoscopic group despite infiltration of the operative site with Bupivacaine. Resumption of domestic activities was also more rapid (three vs seven days ; p=.ooi) as was return to work (14 vs 28 days ; p= 0.002). Subsequent recurrence rates were not mentioned.
Payne performed an identical study with two groups of 45 patients. It was noted that the cost of laparoscopy was greater (+20%) but there were no differences in the other parameters studied Recurrence rates were not evaluated. Vogt with a series of 61 patients compared the Mac Vay and Bassini operations with the laparoscopic placement of ePTFE prostheses. There were two conversions out of 31 (6%) and 2 recurrences (6%) in each group when contacted by telephone at one year.
Barkum performed a randomised controlled trial with two groups of 49 and 43 cases respectively. Once again the laparoscopic groups experienced less post operative pain and had a shorter recovery time. The recurrence rate at 14 months (4 out of 43 or 10%) was comparable for both groups. The methodology of this study could be criticised because of the wide variety of operative techniques employed in the “conventional” group (58% were Shouldice operations, 35% Lichtenstein, and 4.8% Mac Vay, as well as a few “plug” procedures). 75% of the laparoscopic group had a pre peritoneal approach. The experience of the operators and the type of anaesthesia used were also somewhat variable.
Finally, the recent work of Wilson has compared the Lichtenstein operation with the intra-peritoneal laparoscopic approach in a prospective study of 242 patients. The length of operation in both groups was comparable but again the duration of hospital stay was shorter for the laparoscopic group (one vs two days) as was the time to return to work (10 vs 21 days; p=o.ooi). Interestingly there were no apparent differences in post operative comfort and analgesic consumption.
The work we report here is the first to compare two essentially identical operations that differ only in their means of approach (open or laparoscopic) and the type and size of prostheses used.
The nature of dissection of the pre peritoneal space in both operations is exactly the same, albeit somewhat slower by the laparoscopic method, especially in the case of bilateral and/or recurrent hernias .
It must be said that there was a relatively high incidence of accidental pneumoperitoneum occuring (27.4%) during dissection of the hernia sac, particularly in the case of recurrent hernias. This reduces the amount of space for dissection, but is easily controlled by insertion of an intra-peritoneal Verres needle which is left open. In one case only, an obese patient, did this event necessitate conversion.
The conversion rate (6% or three cases) illustrates the limits of the pre peritoneal route: relative obesity and the size of the hernia. This particularly applies to large inguinoscrotal hernias which in other respects represent an ideal indication for the pre-peritoneal approach.
Four features in favour of the laparoscopic operation have been demonstrated:
A significant reduction in the mean length of hospital stay (3.2 vs
days) which confirms the majority of earlier studies . This could still however be considered relatively long when compared to certain British series . In this regard, Johannet in France has performed this operation on a day surgery basis with good results .
-A significant reduction (4 vs 21.5%; p=0.02) in abdominal wall and urinary pathology.
-Finally, the significant reduction in time off work (17 vs 35 days) in this particular sub-group (40%) accords with data already in the literature .
Recurrence rates are somewhat difficult to evaluate. All our patients were followed up at one year, 95% at two years and 93% at three years. There were three recurrences (6%) all incurred at the beginning of our experience and presentation at one, two and three years respectively. These appreared to result from insufficient coverage of the hernial defects by meshes that were too small. This was verified by laparoscopy and the patients were then treated by the Lichtenstein operation. No further recurrences were noted after the eleventh patient in the series, by which time larger prostheses were being employed (15 x 12 cm). After this modification the recurrence rate became identical to that of the Stoppa operation. One patient treated by the open method had a recurrence at 13 months.
Factors leading to recurrence were studied by Deans (1995b) in a series of 10 cases from a total of 800 operations (0.8%) with a mean follow up of 14 months. The basic cause was once again a prosthesis of insufficient size, failing to come into contact with Cooper’s ligament or remaining partially rolled up. The author treated these cases laparoscopically by placement of a second larger mesh.
The size of the prosthetic mesh should be the same whether the hernia be repaired openly or laparoscopically . The direct relationship between mesh size and incidence of recurrence is well established. The current trend is not only to use prostheses that are as large as possible but also to insert large mono-piece (30 x 12 cm) meshes in bilateral hernias , even though their placement may be somewhat difficult. This so-called “bikini” prosthesis proposed by Dean produced excellent results in a series of 150 cases with a mean operative duration of 43 minutes, a hospital stay of one day, return to work by seven days, and no recurrences in an 18 month follow-up period.
The operative experience of the surgeon obviously also plays an important role, as seen in our series. Kald confirmed this in 1995 with seven recurrences out of 200 (3.5%) at one year, six of which occurred in the first 31 cases.
On the basis of our results and those of the literature one could confidently assume that, given adequate mastery of the technique (50 cases) and the use of large mono-piece prostheses, as in Stoppa’s original operation, laparoscopy will come to assume increasingly greater importance in the treatment of groin hernias.
Taking into account the inclusion and exclusion criteria of this study, the laparoscopic approach would seem preferable to the “classical” Stoppa operation in terms of the post operative quality of life, length of hospital stay and interruption of occupational activity. The higher incidence of recurrence (6%) in the laparoscopic group merely reflects initial operative inexperience and the use of inadequately sized prostheses. The preferential employment of large «mono-ріесе» meshes particularly for bilateral hernias reduces the recurrence rate towards that of open operations. The laparoscopic pre-peritoneal method is thus set to become an accepted means of inguinal hernia repair.
a- Length of operation: This was comparable for unilateral hernias but significantly longer for bilateral and recurrent types.
b- Intra operative complications:
In the “Stoppa group” there were two instances (4%) of haemorrhage into the retropubic space.
In the “laparoscopic group”, there was only one case of bleeding during dissection of the spermatic cord. By contrast, there were 14 cases (77.4%), mainly in recurrent hernias (n=io), where the peritoneum was breached leading to a pneumo-peritoneum. There were three conversions (6%): one in an obese patient, but BMI< 30, another with large bilateral hernias and a third where a pneumo-peritoneum significantly reduced the field of vision in the pre-peritoneal space. These illustrate the limitations of the totally preperitoneal approach. Suction drainage was necessary in 3 cases following laparoscopy and in 7 after the Stoppa operation . The mean duration of drainage was comparable in both groups (2.8 ± 1.7 days).