Transgastric appendicectomy

Authors


Correspondence to: Professor G. Kaehler, Central Interdisciplinary Endoscopy, University Medical Centre Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1–3, 68167 Mannheim, Germany (e-mail: georg.kaehler@umm.de)

Abstract

Background

Experimental studies and small anecdotal reports have documented the potential and feasibility of transgastric appendicectomy. This paper reports the results of the new technique in a selected group of patients.

Methods

From April 2010 transgastric appendicectomy was offered to all patients with acute appendicitis, but without generalized peritonitis or local contraindications.

Results

Of 111 eligible patients 15 agreed to undergo the transgastric operation. After conversion of the first case to laparoscopy because of severe inflammation and adhesions, the following 14 consecutive transgastric procedures were completed. Two patients with initial peritonitis required laparoscopic lavage 4 days after transgastric appendicectomy, but no leaks were detected at the appendiceal stump or stomach.

Conclusion

These preliminary results have shown the feasibility of this innovative procedure. Additional studies, however, are required to demonstrate the specific advantages and disadvantages of this approach, and define its role in clinical surgery.

Introduction

The concept of further reducing surgical access trauma fascinates gastroenterologists and surgeons alike[1, 2]. Yet, the practical application remains difficult. Although gastroenterologists remain in the experimental stage of flexible natural orifice transluminal endoscopic surgery (NOTES) procedures, surgeons are actively modifying standard laparoscopic operations by use of smaller and fewer incisions. As appendicectomy is generally a simple surgical procedure, it was tested in the early phase of clinical NOTES[3][4, 5]. Surprisingly, although successful in initial cases, it has not yet found its way into routine clinical use. The non-elective character of the procedure and the lack of surgeons experienced in flexible endoscopy may be major reasons for this. Moreover, ethical concerns in regard to replacement of a well established surgical treatment with a non-established procedure may also be responsible.

After training in transgastric procedures on pigs over a 2-year period, and successful testing of the viability of absorbable loops for flexible endoscopes in an animal study[6, 7], transgastric appendicectomy was offered to patients with acute appendicitis beginning in April 2010. This paper describes the surgical technique and reports the initial results.

Methods

The study protocol was approved by the local ethics committee. Special patient insurance was taken out. The diagnosis of acute appendicitis was based on clinical examination, haematological and inflammatory para-meters, and ultrasonography. No other diagnostic modalities were used. All patients diagnosed with acute appendicitis were screened for contraindications to transgastric appendicectomy. Patients with suspected perforated appendicitis, obstruction in the upper gastrointestinal tract, previous upper abdominal operations, pregnancy, liver cirrhosis and body mass index exceeding 30 kg/m2 were excluded. The stomach was assumed to be non-sterile owing to increased pH in patients being treated with proton pump inhibitors, so they were also excluded from the study.

Transgastric appendicectomy was explained to patients who met the inclusion criteria as a new minimally invasive operation that uses only one transumbilical 5-mm incision, but has an unknown risk of complications from the additional gastric incision. Informed consent was then obtained.

Before transfer to the operating theatre, all patients received oral lavage with octenidine dihydrochloride (Octenisept®; Schülke & Mayr, Norderstedt, Germany). After induction of standard general anaesthesia the patient was positioned on a vacuum mattress to facilitate extreme positioning during the operation. Before the procedure a single-shot antibiotic was administered, consisting of 500 mg ceftriaxone and 500 mg metronidazole.

The procedure was carried out using a double-channel therapeutic gastroscope (PV-TG 2; Karl Storz Endoskope, Tuttlingen, Germany) together with an endoscopy system (light source: xenon 100; video processor: Telecam® SL II; documentation system: Aida® control; Karl Storz Endoskope), which was sterilized with ethylene oxide and packaged in a sterile box. One of the channels was connected to a carbon dioxide insufflator (Thermoflator®; Karl Storz Endoskope), with a flow rate of 6 l/min and carbon dioxide pressure of 15 mmHg, and the other was used for instrumentation.

The procedure began with a routine gastroscopy to exclude abnormalities in the oesophagus and stomach. After identification of the middle third of the anterior wall of the corpus by ‘finger-tip trial’ from the left epigastrium (similar to endoscopic gastrostomy), the gastric wall was punctured via a gastroscope with a needle knife (needle papillotome for guidewire, MTW Endoskopie, Wesel, Germany; HF Generator ICC 200, Erbe Elektromedizin, Tübingen, Germany) and a guidewire (Jagwire® 450 cm; Boston Scientific, Ratingen, Germany) was inserted deeply. After removal of the needle knife a dilatation balloon (Rigiflex® 18–19–20 mm; Boston Scientific Deutschland) was introduced and the gastric wall dilated (Video S1, supporting information). While deflating the balloon the gastroscope was advanced into the peritoneum and a capnoperitoneum established. This was followed by laparoscopic orientation, control of the gastric entry point with the retroflexed gastroscope, and confirmation of the indication for appendicectomy.

Patients were moved into a Trendelenburg position for better exposure of the caecum. After standard skin disinfection a 5- or 3-mm trocar was inserted in the umbilicus under endoscopic control. As the two instrumentation channels in the gastroscope could be moved independently from each other, it was necessary to use an additional instrument to apply traction to the tissues. The appendix was then put under traction with a grasper and, after anatomical orientation, the mesoappendix was dissected using a needle knife (Video S2, supporting information). A coagulation grasper (FD-410LR; Olympus Medical Systems, Tokyo, Japan) or metal clips (Resolution® Clip; Boston Scientific Deutschland) were used for haemostasis if necessary.

Ligation of the appendix was carried out using specially developed 40- or 20-mm NOTES loops (Serasynth® NOTES loop; Serag-Wiessner, Naila, Germany), which consist of a 0.45-mm (USP 0) polydioxanone loop. Three loops were placed, two at the base of the appendix and one approximately 10 mm away from the base, with a flexible loop applicator (HX-20U-1; Olympus Deutschland, Hamburg, Germany) (Video S3, supporting information).

Dissection of the appendix between the loops was carried out using endoscopic scissors (MTW Medizintechnik, Wesel, Germany) and a ‘cold cut’ (Video S4, supporting information). This was necessary as the use of monopolar current in this location could cause coagulation under the ligation loop owing to narrowing of the path of electrical current. The appendix was then grasped with the coagulation grasper and extracted through the oesophagus (Video S5, supporting information). The use of a bag was regarded as unnecessary because of the low risk of infection in the stomach compared with the abdominal wall.

After fixation of an over-the-scope clip (OTSC 12/6a-220; Ovesco Endoscopy, Tübingen, Germany) to the tip of the gastroscope, the latter was inserted carefully and a twin grasper applied. This instrument allowed grasping of both edges of the gastric opening independently from each other with subsequent locking. After full-thickness grasping of the gastric wall the tissue was pulled into the transparent hood of the gastroscope. The clip was released by a suture (Video S6, supporting information). The tightness of the gastric closure was checked by gastroscopic inspection. Finally, the capnoperitoneum was evacuated through the trocar, which was removed thereafter.

After extubation all patients received a double standard dose of proton pump inhibitor (2 × 40 mg pantoprazole) for 8 days. Oral intake of 500 ml tea was allowed on the first day, liquid food on the second and normal food on the third postoperative day. Discharge depended on the patient course and subjective well-being. Abdominal ultrasound examination was performed routinely before discharge. Quality of life was measured using the gastrointestinal index Short Form 8 (SF-8®; QualityMetric, Lincoln, Rhode Island, USA), and patients were interviewed by telephone after 6 weeks and 6 months.

Results

Between April 2010 and April 2011, 111 patients were diagnosed with acute appendicitis at this hospital. If they did not meet the exclusion criteria and a surgical endoscopist was available, transgastric appendicectomy was explained and offered to the patient. Fifteen of these patients agreed to undergo the transgastric operation (Table 1). The diagnosis of acute appendicitis was found to be correct in all patients. In all except the first patient, transgastric appendicectomy could be performed as described above by one of two endoscopically experienced surgeons.

Table 1. Patient details
No.SexAge (years)BMI (kg/m2)ASA gradeIntraoperative detailsProcedure time (min)Postop. complicationsHospital stay (days)
  1. BMI, body mass index; ASA, American Society of Anesthesiologists.
  2. aReadmitted later.
1M4923.9IConversion to laparoscopy100None6
2M2423.2I 120None4
3M1924.1I 80None3
4F2235.4II 80Douglas abscess8
5F1822.1II 105None2
6M1923.0II 105None3
7F3426.5II 105None3
8M1622.7IITechnical problems with loop applicator, solved by ligation via umbilical trocar70None4
9M7244.6IIIDivision of specimen into two pieces owing to its size135None5
10F4125.3IThree metal clips used to stop bleeding100None4
11M2125.9I 95None2
12M2127.1II 59None1
13M2926.5II 120None3
14M1923.5II 120Douglas abscess4a
15M7420.3II 150None3

In this series there were no problems with gastric access. No damage of neighbouring organs was recorded. In one patient ligation of the appendix via the transumbilical trocar was necessary owing to technical problems with the loop applicator. Monopolar coagulation with the coagulation grasper was sufficient to stop bleeding in all but one patient. In the latter patient three haemostatic metal clips had to be applied. In an obese patient with severe inflammation, the specimen was divided into two parts to allow passage through the gastric wall. No relevant bleeding or other complications occurred. Median duration of operation was 105 (range 59–150) min.

Two patients required laparoscopic revision with lavage to treat pelvic abscesses. In both, the appendiceal stump and gastric closure site were found to be tight at the time of laparoscopic revision. Both patients had severe purulent peritonitis with extensive pus collection at the time of primary appendicectomy.

All other patients had an uneventful postoperative course. Median hospital stay was 3 (range 1–8) days. Telephone interviews after 6 weeks and 6 months (in all patients) revealed no further complications.

The small number of patients did not allow analysis of quality of life as measured by SF-8®. There were, however, clinically no remarkable differences between these patients and those who underwent laparoscopic appendicectomy.

Discussion

Unlike the rapid establishment of laparoscopic surgery in clinical medicine, the implementation of NOTES seems to have been considerably slower. Even though there have been several successful experimental trials, this innovative approach has still not found its way into clinical practice.

Two case reports by Park and Bergström[8] and Horgan et al.[5] described one and two transgastric appendicectomies respectively. There is only one larger published series of NOTES appendectomies[4]. In this multi-institutional registry study, Zorron and co-workers[4] reported on 14 transgastric appendicectomies among 362 NOTES procedures. The technique used was not described in detail but the procedure was performed using two transabdominal trocars. Access to the abdominal cavity and closure of stomach was done laparoscopically. The complication rate for the transgastric appendicectomy (21·4 per cent) was as high as that for all other transgastric procedures (23·1 per cent) and higher for transvaginal appendicectomies (8·1 per cent)[4].

Although single-port appendicectomies reduce the number of abdominal ports, they are associated with one larger incision. In the event of an acute inflammatory disease, this could cause wound healing problems. Therefore, the transgastric access could be an interesting alternative.

In the present study, NOTES appendicectomies were performed by a standardized technique using a flexible gastroscope. Based on vast experience both in interventional endoluminal endoscopy and in laparoscopic surgery a feasibility study for transgastric appendicectomy was designed. This clinical series was preceded by an extensive experimental preparation phase. Fortunately, the planned transgastric procedure could be performed in all but one of the patients. The need for sterile gastroscopes to carry out NOTES procedures is still under debate. In this study gastroscopes were sterilized using ethylene oxide to provide a maximum standard of hygiene.

The low recruitment rate (15 of 111 appendicectomies) reflects cautious discussion with the patients without any pressure to participate in the study. The endoscopy team was available most days and nights.

Considering that this was a fundamentally new surgical procedure, operating times seemed acceptable, although they were obviously longer than those for open or standard laparoscopic appendicectomy. Hospital stays were no shorter than for standard laparoscopic appendicectomy, but this was probably a result of safety concerns. The surgical team wanted to ensure that no serious postoperative complications were missed and patients could probably therefore have been discharged considerably earlier. This series suggests that transgastric appendicectomy is feasible as a routine procedure after an adequate preparation phase. The technique described seems to be reasonably safe in uncomplicated appendicitis. For broader application of transgastric appendicectomy, standardization of the technique and special training in animal models is mandatory. Experience in interventional endoscopy and the treatment of acute appendicitis are also preconditions.

Caution, however, has to be advised for patients with purulent appendicitis. In two of the present patients this was associated with the development of pelvic abscesses requiring laparoscopic intervention. This was probably the result of greater difficulty in performing intraoperative lavage during the transgastric procedure compared with laparoscopic or conventional surgery. This is in part supported by data from large randomized studies and meta-analyses comparing laparoscopic with conventional appendicectomy. In some publications there was a trend towards more intra-abdominal abscesses in complicated appendicitis for the laparoscopic group[9, 10]. This is generally attributed to the fact that it is technically more difficult and obviously more time-consuming to perform an adequate lavage laparoscopically than conventionally. Therefore, it is probably wise to convert to laparoscopy or even conventional surgery in patients with peritonitis as the rate of postoperative intra-abdominal abscess formation is increased.

It is remarkable that these results could be achieved with instruments not designed specifically for intra-abdominal use. Further advances are expected from use of flexible endoscopes with several instrumentation channels and the ability to move instruments independently from the entire scope.

Building on these promising results, further clinical investigations, including a multicentre study, are now being planned, which will hopefully prove the feasibility and safety of transgastric appendicectomy.

Acknowledgements

Ovesco Endoscopy (Tübingen, Germany) provided over-the-scope clips for the study.

Disclosure: The authors declare no other conflict of interest.

Ancillary