Versatility of One-Trocar Surgery in Children

Giovanni Cobellis, MD, PhD, Giovanni Torino, MD, Carmine Noviello, MD, PhD, Alba Cruccetti, MD, PhD,Luciano Mastroianni, MD, Giuseppe Amici, MD, and Ascanio Martino, MD

Abstract

Background/Purpose: One-trocar surgery (OTS) includes all video-surgical techniques performed using a single10-mm port and an operative scope. These techniques can be completely endoscopic or endoscopic assisted.Since 1997, OTS has become the approach of choice in our institution for a variety of laparoscopic, retro-peritoneoscopic, and thoracoscopic operations. We report our experience with this technique.Methods: Four hundred fifty-eight patients (age range, 3 months to 17 years) underwent OTS from October 1997to December 2008. The procedures were transumbilical laparoscopic-assisted (TULA) appendectomy (182 pa-tients), TULA small bowel resection (14 patients), TULA intestinal biopsies (7 patients), laparoscopic adhesiolysis(6 patients), laparoscopic-assisted liver biopsies (5 patients), laparoscopic revision of peritoneal dialysis catheter(3 patients), retroperitoneoscopic varicocelectomy (202 patients), retroperitoneoscopic-assisted renal biopsies (4patients), retroperitoneoscopic drainage of posttraumatic urinoma (1 patient), retroperitoneoscopic-assistedpyeloplasty (15 patients), and thoracoscopic pleural debridement and decortication for empyema (19 patients).Results: The procedure was completed using only one trocar in 399 cases (87.1%). All conversions to multitrocaror open surgery were elective and regarded the retroperitoneoscopic approach during the learning curve (28 of222, 12.6%; 21 varicocelectomies and 7 pyeloplasties) and the TULA appendectomy because of the appendixmobilization failure (31 of 182, 17%). There were no intraoperative or postoperative complications related toOTS. Wound infection was observed after two TULA appendectomies (1.3%).Conclusions: According to our experience, OTS is a feasible and versatile technique in pediatric surgery, pro-viding a safe, effective, and the least invasive treatment for several different diseases.

Introduction

One-trocar surgery (OTS) includes all minimally in-vasive techniques performed using a 10-mm trocar and

an operative scope (Fig. 1). These procedures can be com-pletely endoscopic or endoscopic assisted. In 1992, Pelosiand Pelosi first reported the laparoscopic-assisted single-puncture appendectomy in adults,1 and in 1998, Espositodescribed the first cases of one-trocar appendectomy inchildren.2 Since our first report in 2001,3 the one-trocar ap-proach has been increasingly and widely applied in our in-stitution for a variety of laparoscopic, retroperitoneoscopic,and thoracoscopic operations. In this article, we report ourexperience with OTS.

Patients and Methods

A retrospective cohort comprising 458 children op-erated with OTS approach between October 1997 and

December 2008 in a single pediatric surgical center wereaudited.

The indications for OTS laparoscopic approach were ap-pendicitis (182 patients), gastrointestinal bleeding (12 pa-tients), abdominal cysts (3 patients), Hirschsprung’s disease(HD) (3 patients), suspected hypoganglionosis (3 patients),recurrent abdominal pain in previous laparotomy (6 patients),liver diseases (5 patients), and peritoneal dialysis catheterdislocation (3 patients). The indications for OTS retro-peritoneoscopic approach were grade 3 varicocele (202 pa-tients), suspected renal lymphoma localization (2), nephroticsyndrome (2 patients), ureteropelvic junction (UPJ) obstruc-tion (15 patients), and posttraumatic pararenal urinoma (1patient); OTS thoracoscopic approach was performed formultiloculated pleural empyema (19 patients).

The following parameters were analyzed: technical prob-lems in the performance of the procedure, operative time,intraoperative complications, postoperative complications,postoperative stay, recurrence, cosmesis.

Paediatric Surgical Unit, Salesi Children’s Hospital, University Politecnica delle Marche, Ancona, Italy.

JOURNAL OF LAPAROENDOSCOPIC & ADVANCED SURGICAL TECHNIQUESVolume 21, Number 6, 2011ª Mary Ann Liebert, Inc.DOI: 10.1089/lap.2010.0063

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For dichotomous outcomes, Fisher’s exact test was per-formed, with a significance assessed at a P value of less than.05 (two-tailed).

Surgical technique

One-trocar laparoscopy. The patient is placed in a supineposition on the operating table. A 10-mm Hasson trocar isinserted in an ‘‘open’’ fashion through the umbilicus andpneumoperitoneum established up to a pressure of 12 mmHg. The operative scope is introduced and a complete ex-ploration of the abdominal cavity is performed.

Transumbilical laparoscopic-assisted surgery:Appendectomy. The appendix is grasped laparoscopically

with an atraumatic instrument introduced through the oper-ative channel of the scope and externalized through the um-bilicus. Appendectomy is performed outside the abdominalcavity using the conventional technique (Fig. 2). At the end ofthe procedure, the bowel is returned inside the abdominalcavity and the laparoscopic control always performed. If thetransumbilical intestinal exteriorization is unsuccessful, lap-aroscopic multitrocar or laparotomic conversion is necessary.

Meckel’s diverticulum and small bowel pathologies. Theaffected loop is grasped and exteriorized through the umbilicusfor the extracorporeal conventional surgery (diverticulectomy,intestinal resection, and anastomosis). When the bowel anom-

aly is not directly identified during the laparoscopic explora-tion, the terminal ileum is transumbilically extracted and thesmall bowel is examined outside the abdominal cavity.

Intestinal biopsies. Seromuscular or full-thickness biopsiesof the colon and ileum are similarly obtained in selected casesof HD (total colonic HD and rectosigmoid HD to identify thelevel of ganglionated bowel during transanal endorectal pull-through), suspected hypoganglionosis after rectal suction bi-opsies, and extended vascular intestinal malformation.

One-trocar intracorporeal laparoscopy:Adhesiolysis. Diagnostic laparoscopy is performed using

the operative laparoscope. Intestinal adhesions to the ab-dominal wall are lyzed with scissors or by diathermy intro-duced through the operative channel. Additional trocar canbe required when the adhesions are too extensive.

Revision of peritoneal dialysis catheter. The trocar is in-serted using the open approach in the lateral quadrant op-posite to the catheter exit site to obtain a greater operativespace. The displaced catheter is freed from the possible ad-hesions and moved in the proper position.

Liver biopsies. Tru-cut biopsies are percutaneously ob-tained under laparoscopic control. Hemostasis is accom-plished by compression on the sites of the biopsies.

One-trocar retroperitoneoscopy. The patient is placed inflank position. A 10-mm Hasson trocar is inserted in an‘‘open’’ fashion below the apex of the 12th rib (Fig. 3), and CO2

is insufflated up to a pressure of 12–15 mm Hg. The retro-peritoneal dissection to develop the working space is per-formed under visual control using a blunt-tipped dissectorinserted through the operative scope. The psoas muscle is themain retroperitoneoscopic landmark.

Varicocelectomy: Following the psoas muscle, the ureterand spermatic vessels are identified. The vessels (both arteryand vein) are cauterized with bipolar forceps and cut.

Pyeloplasty: The kidney is mobilized posteriorly and theureter identified. The ureteropelvic junction and the pelvis areendoscopically isolated and externalized through the trocarincision to perform a conventional pyeloplasty outside theabdominal cavity (Fig. 4).

Renal biopsies: Biopsies are performed both percutane-ously, under retroperitoneoscopic control, or endoscopically,using a spoon biopsy forceps.

Drainage of posttraumatic urinoma: A large drainage tubeis inserted into the retroperitoneal space through the opera-

FIG. 1. One-trocar surgery instruments.

FIG. 2. Appendix externalized through the umbilicus. FIG. 3. Incision for one-trocar retroperitoneoscopy.

550 COBELLIS ET AL.

tive channel of the scope, after minimal retroperitoneoscopicdissection.

One-trocar thoracoscopy. Pleural empyema: The patientis placed in full lateral position. Single lung ventilation is notmandatory, but in some instances it facilitates the procedure.A 10-mm Hasson trocar is inserted in an ‘‘open’’ fashion on themiddle axillary line at the 4th–5th intercostal space, and CO2

is insufflated up to a pressure of 4 mm Hg. The operativescope is introduced and pleural adhesions are initially dis-rupted with the camera movements inside the pleural space.Pleural debridement is performed: fibrinous septa are com-pletely disrupted using endoscopic blunt tip dissectors; fluidis aspirated and debris removed from the pleura. In the moreadvanced empyemas, decortication is performed by remov-ing the organized material from the visceral and the parietalpleural surfaces. At the end of procedure, a large chest tube ispositioned under vision through the trocar site.

Results

OTS was performed on 458 children. The mean age was 6years (range, 3 months to 17 years). The operations were 217OTS laparoscopies: 182 transumbilical laparoscopic-assisted(TULA) appendectomies, 14 TULA small intestine resection(10 bleeding Meckel’s diverticulum, 2 cystic Meckel’s diver-ticulum, 1 cystic duplication, 1 jejunal hemangioma), 7 TULAintestinal biopsies (1 extended intestinal vascular malforma-tion presented with bleeding, 1 total colonic HD, 2 recto-sigmoid HD during transanal endorectal pull-through, 3normal histology in suspected hypoganglionosis), 6 ad-hesiolysis, 5 laparoscopic-assisted percutaneous needle liverbiopsies (1 metastatic Wilms’ tumor, 1 focal nodular hyper-plasia, 1 histiocytosis, 2 cirrhosis), and 3 revisions of perito-neal dialysis catheters; 222 OTS retroperitoneoscopies: 202varicocelectomies, 4 renal biopsies (2 lymphomas, 2 nephroticsyndromes), 15 pyeloplasties, and 1 drainage of a posttrau-matic perirenal urinoma; 19 OTS thoracoscopic pleural de-bridements and decortications for empyema.

The operation was completed using only one-trocar in 399cases (87.1%). There were no intraoperative or postoperative

complications related to OTS. The operating times and hospitalstay for the different procedures are shown in Tables 1 and 2,respectively. All conversions to multitrocar or open surgerywere elective. During the learning curve, 21 of 202 (10.3%)varicoceles needed conversion to laparoscopic transperitonealvaricocelectomy because of the lack of orientation during theretroperitoneoscopic dissection and impossibility to identifythe spermatic vessels. There were technical difficulties in 7 of 15(46.6%) pyeloplasties, because of a fixed ureteropelvic junctionor polar vessels, which did not allow the ureteropelvic junctionextraction outside the abdominal cavity; all these 7 patientsneeded elective conversion to open surgery.

Thirty-one of 182 (17%) appendectomies needed openconversion because of the appendix mobilization failurecaused by a fixed cecum or peritonitis. Umbilical wound in-fection was observed after two TULA appendectomies (1.3%).

At follow-up (range, 6–140 months), varicocele persistence/recurrence occurred in 21 of 181 (11.6%) retroperitoneoscopicvaricocelectomies and recurrent ureteropelvic junction ob-struction was observed in 1 patient (6.7%).

FIG. 4. Ureteropelvic junction externalized in one-trocar–assisted pieloplasty.

Table 1. Operative Time in One-Trocar Surgery

ProceduresRange

(minutes) Mean

Appendectomy 23–100 41.3Intestinal resection 40–120 72.8Intestinal biopsy 25–70 39.6Adhesiolysis 32–75 51.4Liver biopsy 20–45 29.5Revision of peritoneal

dialysis catheter25–45 35.6

Varicocelectomy 15–55 24.2Renal biopsy 25–45 35.6Drainage of posttraumatic

urinomaa

a a

Pyeloplasty 75–180 123.7Thoracoscopic debridement

and decortication60–160 93.8

a1 patient: 32 minutes.

Table 2. Hospital Stay in One-Trocar Surgery

ProceduresRange(days) Mean

Appendectomy 2–6 2.9Intestinal resection 3–7 4.2Intestinal biopsy 3–5 3.8Adhesiolysis 2–4 3Liver biopsy 1–2 1.2Revision of peritoneal

dialysis catheter2–6 4

Varicocelectomy 1–3 1.6Renal biopsy 1–2 1.5Drainage of posttraumatic

urinomaa

a a

Pyeloplasty 3–6 4.5Thoracoscopic debridement

and decortication8–35 21.2

a1 patient: 20 days.

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Discussion

Minimally invasive techniques have the advantages overopen surgery in terms of trauma, postoperative pain, and cos-metic results. Most of the laparoscopic, retroperitoneoscopic,and thoracoscopic procedures described in literature are per-formed using two to five trocars for the scope and the in-struments. The operative scope allows operating using onlyone-trocar and few instruments.

The first description of OTS was appendectomy and waspublished in 1992 by Pelosi and Pelosi.1 In 1998, Esposito2

reported his initial experience in performing OT appendec-tomy in 25 children. He concluded that the one-trocar ap-pendectomy is easy to perform, but the use of the operativescope can be difficult because of the co-axial movement of thecamera and the instrument, which sometimes makes difficultorgan exploration and manipulation. In our experience, OTShas been a safe and effective approach, with minimal com-plications and better cosmetic results (Fig. 5) than open ormultitrocar surgery.3 As our experience with OTS has in-creased, we have been able to expand its application in manypediatric surgical fields. In this study, 458 operations wereperformed. The predominant procedures were TULA ap-pendectomies (182 cases) and retroperitoneoscopic var-icocelectomies (202 cases), but OTS was also applied in manyselected surgical procedures without extensive laparoscopicorgan manipulation.

In our experience, appendectomy was easily performed inuncomplicated appendicitis, when preoperative ultrasounddid not reveal sign of perforation; however, elective conver-sion to open surgery was necessary in 17% of cases because ofthe cecum and appendix mobilization failure. After thelearning curve, the operative time for appendectomy becameshorter, but the conversion rate did not change. It is stillcontroversial whether the retrieval of the appendix throughthe umbilicus results in a higher infection rate compared withother laparoscopic or open techniques. In 2008, Visnjic4

compared TULA appendectomy with laparoscopic appen-dectomy in children. The author reported a wound infectionrate of 13.7% and 4.6%, respectively, concluding that this in-fection rate was not significant (P value = .17). Recently, Sesia

et al.5 conducted a retrospective chart review of 262 childrenwith acute uncomplicated appendicitis who underwent OTappendectomy, reporting a 2.7% infection rate. In our series,the wound infection rate after TULA appendectomy was1.3%. We suppose that our lower infection rate was related tothe preoperative selection of the patients in whom TULAapproach was performed only in case of uncomplicatedappendicitis, without preoperative clinical and ultrasono-graphic signs of perforation. Moreover, laparotomic conver-sion was our preferred choice in patients with higher risk ofinfections, when a localized peritonitis constricting the mo-bility of the caecum and appendix was found during the OTlaparoscopic exploration.

Intestinal biopsies, small bowel exploration, and resectionare also safely performed through the TULA approach. In ourseries, 14 patients underwent transumbilical small bowel ex-ploration and resection without complications. We found 12Meckel’s diverticulum, 1 ileal duplication, and 1 jejunalhemangioma. The laparoscopic intracorporeal search forMeckel’s diverticulum is considered time consuming and notcompletely reliable.6

In the jejunal hemangioma case, the child presented withgastrointestinal bleeding and the Meckel’s scan was positive.TULA small bowel exploration outside the abdominal cavitywas performed and diverticulum was not found; the hem-angioma was identified as a small soft palpable lesion of thebowel at about 40 cm from the Treitz, and in our opinion,intracorporeal laparoscopic small bowel exploration couldnot be effective in this case.

Sauer et al.7 proposed the umbilical incision to performcolonic biopsies for identify the level of ganglionated bowelbefore to start the mucosectomy during the transanal en-dorectal pull-through for HD. In our experience, the TULAapproach was an advantageous minimally invasive alterna-tive to perform seromuscular biopsies of the colon and theileum for total colonic HD diagnosis and rectosigmoid HD toidentify the level of ganglionated bowel during transanalendorectal pull-through; full-thickness biopsies were alsoobtained in patients with suspected hypoganglionosis, afterrectal suction biopsies and in a case of extended intestinalvascular malformation.

Malfunction of peritoneal dialysis catheters result frommigration of the catheters into the upper abdomen or adhe-sions.8 Adhesiolysis and revision of peritoneal catheters canbe successfully performed using only one trocar. We per-formed three peritoneal dialysis catheter revisions. Catheterwas freed from adhesions and moved in the proper position;dialysis was started few hours after the procedure and therewas no recurrence.

In the last years, OTS have been also successfully applied toperform procedures as revision of the peritoneal shunt cath-eters for hydrocephalus and gastrostomy in neurologicallyimpaired children.9,10

Regarding OT retroperitoneoscopy varicocelectomy em-ploying the Valla technique, the largest subgroup of patientswas undergoing OTS.11 In this group of patients, the con-version rate of 10.3% was directly related to the learningcurve. In fact, in a previous study, we report a 17.6% (17 out of97 patients) conversion rate to a laparoscopic transperitonealmultitrocar technique because of the difficulty in orientationinside the retroperitoneal space,12 but in the last 105 cases theconversion rate decreased to 3.8% (P = .002). The recurrence/

FIG. 5. Cosmetic results after transumbilical laparoscopic-assisted small bowel resection for Meckel’s diverticulum.

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persistence rates of retroperitoneoscopic varicocelectomy inour previous (11.2%) and present (11.6%) series are similar toother techniques.12

Retroperitoneoscopic pyeloplasty requires a special lapa-roscopic skill, mainly in infants,13 owing to the small opera-tive space. In 2004, Farhat et al.14 reported the initialexperience in performing retroperitoneal-assisted laparo-scopic pyeloplasty in 9 children. After retroperitoneoscopicdissection using three trocars, the ureteropelvic junction wasbrought up through a 10-mm trocar site to the skin level andpyeloplasty was performed over a Double-J stent. In twopatients, mobilization of ureteropelvic junction was inade-quate and open conversion was performed. One-trocar–assisted pyeloplasty (OTAP) was first described by Lima et al.in 2007.15 OTAP was performed on 16 patients using the op-erative scope and there were no conversions. The authorsconcluded that OTAP allows to perform the Anderson-Hynespyeloplasty through a 10-mm lumbar incision, especially invery small children and also in presence of crossing vessels.Also, in our initial experience, this approach was more ad-vantageous in infants than in older children; in fact, in infants,the thin abdominal wall allows the externalization of the ur-eteropelvic junction more easily. The conversion rate was highin our series (46.6%), but in these patients only a small en-largement of the lumbar incision allowed to perform theconventional pyeloplasty. There was one recurrent ureter-opelvic obstruction due to an unrecognized proximal ureteralhypoplasia, and therefore, it was not related to one-trocartechnique. Caione et al.13 performed a study comparing theoutcomes in young children consecutively enrolled for opendismembered pyeloplasty (25 patients) and OTAP (28 pa-tients). The median operative time was significantly longerwith OTAP (95 versus 72 minutes; P < .05). OTAP was su-perior to open pyeloplasty in terms of postoperative hospitalstay (median: 2.4 days with OTAP and 6.1 days with the openprocedure; P < .05), postoperative pain, and cosmetic results.

OTS can also be an alternative to the percutaneous ultra-sound-guided procedures such as drainage positioning andtru-cut biopsies in selected cases after interventionist radiolo-gist consulting, particularly when the risk of bleeding is high.

Renal trauma is considered a contraindication to laparo-scopic surgery. We performed successfully OT retro-peritoneoscopy in a patient with a major renal trauma to draina perirenal urinoma. A large drainage tube was insertedthrough the operative laparoscope inside the retroperitonealspace and urinoma resolved without complications. OT renaland liver biopsies were also successfully achieved under en-doscopic control. Operative scope allowed to perform suc-cessful bleeding control after biopsies.

One of the latest innovations in the armory of laparoscopicsurgery is the laparoendoscopic single-site surgery. Thistechnique uses a single multichannel (three or four channels)trocar inserted through a single incision; articulating, prebent,and flexible instruments provide a degree of triangulation inthe operative field to perform surgical procedures.16 This newlaparoscopic surgery is spreading in adult, but it remainsmore sporadic in pediatric age.17 We underline that the la-paroendoscopic single-site surgery and OTS are both mini-mally invasive surgical methods, but they are differentlaparoscopic techniques with own specific devices. In 2004,Martinez-Ferro et al. reported the single-port thoracoscopicdebridement for pleural empyema in 10 children.18 Thoraco-

scopy was performed using a single rigid nonvalved thor-acoport for the contemporary introduction of a 5-mm scopeand 3-mm instruments. We performed OT thoracoscopy forpleural empyema using the operative scope in 19 childrenwithout complications, with good cosmetic results and lesspostoperative pain.

In conclusion, our experience shows that OTS is a versatile,safe, and effective approach in the surgical management ofmany pathologies in children. The indications for theseOT procedures have expanded and can be applied to theminimally invasive operations that do not require great en-doscopic viscera manipulation. The operating time is com-parable with that of conventional technique and complicationrate is low. The main advantage of OTS is the better cosmeticresult than multitrocar techniques.

Disclosure Statement

No competing financial interests exist.

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Address correspondence to:Giovanni Cobellis, MD, PhD

Paediatric Surgical UnitSalesi Children’s Hospital

University Politecnica delle MarcheVia Corridoni 11

Ancona 60123Italy

E-mail: giovannicobellis@tiscali.it

554 COBELLIS ET AL.