The vermiform appendix presenting in a laparoscopic port site hernia.

Laparoscopic port site hernias (PSHs) are uncommon but present a potential source of morbidity due to incarceration of the hernial contents which is usually omental fat or small bowel. We report only the third case of the vermiform appendix presenting in a symptomatic PSH; we discuss the appropriate management of this condition as well as ways in which the incidence of PSHs may be reduced.

INTRODUCTION

The increasing popularity of laparoscopic surgery is attributed, in part, to reductions in the length of hospital stay and post-operative recovery, but aside from these benefits, it will also expose patients to increased risks of complications such as venous gas embolism[1] and to ‘new’ complications such as port site metastasis, and port site hernia (PSH) formation. Most PSHs require subsequent surgical repair.[2]

The presence of the vermiform appendix has been described in most of the anatomically recognised abdominal hernias, but has only been reported twice in a PSH since the advent of laparoscopy.[34] We describe a symptomatic, third case of appendiceal entrapment in a laparoscopic PSH and discuss how PSH incidence may be reduced.

CASE REPORT

A 62-year-old man underwent laparoscopic anterior resection and partial cystectomy for a diverticular colovesical fistula in March 2007. The operation was uneventful and utilised two 12-mm and two 5-mm Endopath® Excel™ bladeless trocars (Ethicon Endosurgery, Cincinnati, USA). Both 12-mm port sites were closed with 2/0 polydioxanone sutures through fascia at the end of the procedure. Eighteen months later, he represented with an uncomfortable lump low in his right iliac fossa; the discomfort was exacerbated by eating. Examination revealed a partially reducible mildly tender lump in the right iliac fossa just above the inguinal ligament. The diagnosis of PSH was made and he was scheduled for open repair, as laparoscopic sublay mesh placement so close to the inguinal ligament would have been unsatisfactory. At operation, a 2-cm fascial defect with a defined hernial sac was identified; the sac was opened and found to contain the vermiform appendix stuck to the wall of the sac in a sliding manner [Figure 1].

Figure 1

The vermiform appendix adherent to the peritoneal sac of a right iliac fossa port site hernia

The appendix was freed from the sac wall [Figure 2] and a standard appendectomy performed with suture ligation of the base without operative field contamination. The hernial defect was repaired directly with interrupted sutures of 1 Nylon and reinforced with an onlay Prolene mesh (Ethicon Inc, Cincinnati, USA). He was discharged from hospital within 24 hours of the procedure and at six-week follow-up was symptom free with no signs of hernia recurrence or mesh infection.

Figure 2

The appendix after freeing from the sac wall prior to appendectomy

DISCUSSION

PSHs are the laparoscopic equivalent of open incisional hernias, and overall are less common than the corresponding open hernia,[5] but are potentially troublesome and most will need repair. They have been classified as early or late onset or of special type depending on the timing of presentation and which abdominal wall layers have failed.[2] Late onset hernias, such as this one, demonstrate fascial failure but with a reconstituted peritoneum, hence there is a true hernial sac. The incidence of PSH varies according to the type and indication for surgery; laparoscopic colectomy for diverticular disease has a higher incidence of PSH than resection for colonic cancer (0.9% vs 0.6%), whereas that for cholecystectomy varies between 0.12 and 0.85%.[2] The incidence of PSH is probably underestimated by any study with short-term follow-up as they will not necessarily capture the late onset hernias which may occur years after the original laparoscopy.[6]

A number of factors predispose to PSH formation, some of which, such as wound infection[7] and obesity,[2] are shared with open surgery and some are unique to laparoscopic surgery. The site and size of the laparoscopic port site are both related to the incidence of subsequent PSH. Herniation is more common at the midline umbilical port, especially if this port site is stretched to facilitate specimen retrieval,[27] compared with laterally placed ports. It is also clear that the incidence of PSH increases with increasing port size. In one study of 840 PSHs, 86.3% occurred in port sites greater than 10 mm in diameter, whereas the incidence fell to 10.9% for ports 8 to 10 mm in diameter and was only 2.7% for ports under 8 mm in diameter.[8] Whilst uncommon, PSH may still occur in smaller port sites including ones as small as 5 mm in diameter.[2] Cutting bladed trocars have an overall higher incidence of PSH than cone-tipped or radially separating trocars; one institution reduced its PSH rate from 1.87 to 0.17% simply by changing to cone-tipped trocars.[9] Release of the pneumoperitoneum before port removal has been suggested as one way of limiting the incidence of immediate hernia which occur as the small bowel is ‘sucked’ into the port track as the port is withdrawn due to a negative pressure effect.[10] Closure of the port site fascial defect is likely to be the easiest way to reduce PSH formation[27] and may be achieved by direct suture or with the aid of specially designed closure devices such as Endoclose™ (Covidien Autosuture, Dublin, Ireland). Closure of small (5 mm) ports is difficult and a practicable compromise is to close all ports bigger than this.

The vermiform appendix has been described in virtually all abdominal wall hernias and its presence in inguinal and femoral hernial sacs have gained eponymous titles, Amyand's and de Garengeot's hernias, respectively.[11] Two previous cases of the appendix appearing in a PSH have been described, one of which presented in a similar manner and location to our case.[4] Standard appendectomy through the hernial defect is the treatment of choice if access permits, otherwise consideration should be given to conversion to a transabdominal route for improved access or if appendicitis has generated significant wound contamination. Mesh hernioplasty is safe if no wound contamination occurs.[12]

CONCLUSION

We present a case of the vermiform appendix presenting in a laparoscopic PSH. We recommend that cutting bladed trocars should be avoided and all ports greater than 8 mm in diameter should be routinely closed to minimise the incidence of this complication. If a PSH is identified, then operative repair is recommended to avoid complications from its contents.