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since the first description of laparoscopic appendectomy by semm in 1983 , several laparoscopic techniques have evolved to attain stump closure .
surgeons can choose between clip , stapler , endoloops [ 2 , 3 ] , or simple sutures as in open surgery .
commonly , endoloops or endostaplers are used for closing the stump of the appendix [ 3 , 4 ] .
we report about the cost of appendiceal stump closure using only sutures in laparoscopic - assisted single - port appendectomy ( spa ) in children .
after institutional review board approval , we retrospectively reviewed the medical records of children who underwent spa between august 2005 and december 2008 at the university children 's hospital of basle ( ukbb ) . according to the world organization of gastroenterology research committee , diagnosis of acute appendicitis
was made by comprehensive anamnesis , physical examination with particular attention of rebound tenderness on the right lower abdominal quadrant , supporting laboratory tests such as white blood cell count ( wbc ) and c - reactive protein ( crp ) , and ultrasound scan of the abdomen .
all children admitted on our emergency room with suspected acute appendicitis were considered for spa and included in this study .
the main purpose of this retrospective single - center study was to analyze the cost for closing the appendiceal stump .
other material and personnel costs for surgery , anesthesia , and costs for operating room and for hospital stay were not considered .
data were stored in an excel database ( microsoft corporation , redmond , wa ) .
as previously described , spa was performed using one 12-mm single - use balloon - trocar ( auto suture , united states surgical / tyco healthcare , type oms - t10bt , norwalk , ct ) with one conventional laparoscopic forceps ( comeg , endoskopie gmbh & co. , type pajunk 12929410 ) . after introducing the trocar through a subumbilical incision ,
after ligature of the basis of the appendix , one purse - string suture and one z - shaped absorbable suture 3/0 vicryl rb-1 placed through the seromuscular base of the caecum closed the appendiceal stump .
all children with suspected appendicitis were managed according to a standard preoperative protocol such as mechanical cleaning of the umbilicus with noncolored octenidine dihydrochloride ( octenisept ) and a loading i.v .- dose of metronidazole and of cefuroxime within 15 minutes before starting surgery .
between august 2005 and december 2008 , 262 children underwent spa , including 146 males ( 55.7% ) and 116 females ( 44.3% ) .
closure of the appendiceal stump using two vicryl rb-1 sutures at a cost of usd 7.5 each was successful in all patients .
conversion to open appendectomy occurred in 35 children ( 13.4% ) and to conventional 3-trocar laparoscopic appendectomy in 9 children ( 3.4% ) . in a previous study , we reported about complications and main outcomes in correlation to histological results .
no insufficiency of the appendiceal stump was observed by ultrasound . during a followup of 69 months ( range , 3069 ) , six obese children ( 2.3% , body mass index > 95th percentile ) developed an intraabdominal abscess after perforated appendicitis .
one child ( 0.4% ) required surgical drainage , and the other five children ( 1.1% ) responded to conservative treatment .
no recurrence of intraabdominal abscess was noted to date . neither a stapler ( cost : usd 276 ) nor endoloops ( cost : usd 89 ) were used .
the median length of hospital stay was 4 days ( range , 3.018.0 ) . as referred earlier ,
the operating surgeon was in 71.7% a resident under the direct supervision of a board certified senior pediatric surgeon .
the increasing pressure of national healthcare insurance to contain costs of inpatient hospitalization aroused our interest in performing this cost - benefit analysis of spa . since this year
now , a flat rate reimbursement replaced the traditional cost - based reimbursement system called tarmed ( tarif mdical ) [ 7 , 8 ] .
appendicitis is the most common cause of acute abdominal disease in children . despite several advantages of laparoscopic appendectomy ( la ) such as less pain , earlier discharge , better cosmesis , and earlier return to normal activities , open appendectomy ( oa ) still represents a standard surgical technique [ 11 , 12 ] . in particular , spa has not yet evolved as gold standard for the treatment of acute appendicitis . compared to oa , la using the three - trocar technique has been shown to induce less postoperative pain and faster recovery of the bowel function but seems to be associated with a higher rate of intraabdominal abscess formation , especially in perforated appendicitis , and with higher costs .
the different manner of closing the appendiceal stump may play a role in developing an intraabdominal abscess   and influence substantially the cost of la .
usually , a noninversion of the appendiceal stump is performed in conventional three - trocar la .
this circumstance could explain a higher rate of intraabdominal abscess in conventional la . since the introduction of spa in mid-2005 at our department , the appendiceal stump is ligated , inverted , and closed by one z - shaped suture .
all of them occurred in obese children ( bmi > 95th percentile ) with perforated appendicitis . in four of them ,
the surgeon carried out a lavage of the peritoneal cavity with saline . despite a controversial discussion in the literature [ 15 , 16 ]
, we hypothesize that the saline lavage may be responsible for bacterial spread throughout the abdomen and the cause of intraabdominal abscess . due to this experience , we only perform suction of the abdominal fluid collections and no more lavage .
a review of the literature shows no significant difference in the incidence of intraabdominal abscess when comparing the suture technique with endoloop and stapler to endoloop only for appendiceal stump closure .
the decision as to which la - technique to use depends on its safety and cost . in our opinion
, spa joins the safety of oa ( i.e. , dissection under direct view ) and the advantages of conventional la ( i.e. , small skin incision and visibility of the entire abdominal cavity ) .
different ways to close the appendiceal stump exist such as stapler , clips , endoloop , or endobag .
in contrast to several reports of single - port or single - incision laparoscopic appendectomy , techniques that involve special trocar , and multiple instruments , our spa - technique requires only one trocar ( usd 172 ) and one conventional laparoscopic instrument and does not necessitate the use of expensive equipment such as retrieval pouch . regarding these facts , our spa - technique is less expensive than conventional three - trocar la reported elsewhere [ 21 , 22 ] .
closing the appendiceal stump using two 3/0 vicryl rb-1 sutures ( usd 15 ) is 5.9 times less costly than by endoloop and 18.4 times less costly than by stapler .
was slightly higher than those reported in the literature , which is related to our learning curve . especially in complicated appendicitis , the operative time was higher than 55 min .
safety of surgical techniques is one of the primary concerns in the literature ; the safety of a surgical technique is characterized by its rate of complications .  
table 1 displays the main outcomes of a review of the literature concerning laparoscopic - assisted single - port appendectomy .
the low rate of perioperative complications and of conversions to oa by extension of the subumbilical incision or to conventional la by the introduction of 2 or more trocars , corroborate the finding that spa remains a safe operative technique .
the safety of oa is commonly accepted , and there are numerous studies underlining the reliability and the safety of la also in complicated appendicitis in children .
however , spa combines the advantages of both open and laparoscopic surgery and allows for use of both skills in open surgical and laparoscopy techniques .
the need for only one single umbilical incision , one conventional laparoscopic instrument without any highly technical devices such as stapler , endoloop , and endobag reduce the time and the mean cost of the spa - operation .
furthermore , the spa - technique is extensible allowing additional trocars or devices such as stapler .
notably , spa can be converted to conventional la at any time for the treatment of additional pathologies .
spa represents an expeditious and reliable technique for appendicitis in pediatric populations . in our opinion , spa is a safe and cost - effective technique .
the main negative features of conventional la , that are longer operative time and operating room cost compared to oa , seem to be not attributable to spa .
additional randomized trials are needed to verify this hypothesis . in our unit , spa is the standard procedure for appendectomy in children .
aim . laparoscopic - assisted single - port appendectomy ( spa ) , although combining the advantages of open and conventional laparoscopic surgery , is still not widely used in childhood . 
 the aim of this study was to evaluate the safety and the cost effectiveness of spa in children . 
 methods . 
 after institutional review board approval , we retrospectively evaluated 262 children who underwent spa . 
 the appendix was dissected outside the abdominal cavity as in open surgery . for stump closure , 
 we used two 3/0 vicryl rb-1 sutures . results . 
 we identified 146 boys ( 55.7% ) and 116 girls ( 44.3% ) . 
 median age at operation was 11.4 years ( range , 1.115.9 ) . 
 closure of the appendiceal stump using two sutures ( cost : usd 15 ) was successful in all patients . neither a stapler ( cost : usd 276 ) nor endoloops ( cost : usd 89 ) were used . during a follow - up of up to 69 months ( range , 3069 ) , 
 six obese children ( 2.3% , body mass index > 95th percentile ) developed an intra - abdominal abscess after perforated appendicitis . 
 no insufficiency of the appendiceal stump was observed by ultrasound . 
 five of them were treated successfully by antibiotics , one child required drainage . 
 conclusion . 
 the spa technique with conventional extracorporal closure of the appendiceal stump is safe and cost effective . in our unit 
 , spa is the standard procedure for appendectomy in children .