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 sils is increasingly being used by pediatric surgeons to perform common abdominal and urological procedures .
appendectomy , cholecystectomy , nephrectomy , hysterectomy , oophorectomy , adrenalectomy , gastric bypass , nissen fundoplication , hernia repair , splenectomy , and colon resection are some of the procedures which are routinely undertaken by the sils approach in some centres [ 15 ] .
the proponents of sils over sls give reasons of cost efficiency ( avoiding use of additional ports ) , cosmesis ( due to fewer port site incisions ) , less post - operative pain and earlier recovery from surgery .
however , the major drawbacks reported for sils have longer operative time due to a learning curve and reduced triangulation of instruments translating into poor ergonomics particularly for the longer procedures .
moreover , there is a paucity of information on the real cost of sils surgery . the intention of this study in comparing costs and operative time of sils versus sls was to improve data to enable effective health care fiscal planning .
a prospectively collected database of operative times and costs was analysed for the years 20082011 .
the number of cases in the two groups was ( n = 21 ) versus ( n = 72 ) , respectively . the operations that were compared included appendicectomy , nephrectomy / heminephrectomy , ovarian cystectomy / oophorectomy , and palomo procedure .  
consumables for sils included use of either olympus triport ( advanced surgical concepts , bray , ireland ) or covidien sils port ( covidien , dublin , ireland ) . in order to curtail costs ,
descriptive statistics and mann - whitney u - test were utilized with spss for windows .
data is quoted as median ( range ) , and p < 0.05 was regarded as significant .
a total of 93 cases were analysed in the study : sils ( n = 21 ) and sls ( n = 72 ) .   for appendicectomy , sils was performed in ten patients ( n = 10 ) and sls in forty eight patients ( n = 48 ) .
the median cost for sils was  397 ( 280603 ) and in sls was  467 ( 175758 ) , p = 0.64 .
operative time in sils was 60 minutes ( 60140 ) and in sls was 103 min ( 40215 ) , p = 0.10 . for nephrectomy / heminephrectomy , four patients ( n = 4 ) had a sils procedure with nine patients ( n = 9 ) subjected to sls .
the median cost in sils was  942 ( 779974 ) and in sls was  1127 ( 5201595 ) , p = 0.11 .
operative time in sils was 130 minutes ( 90180 ) and in sls was 160 minutes ( 70235 ) , p = 0.21 . for ovarian cystectomy / oophorectomy ,
sils was conducted in four patients ( n = 4 ) and sls in six patients ( n = 6 ) . the median cost in sils was  394 ( 223702 ) , whereas in sls was  495 ( 246729 ) , p = 0.56 .
operative time in sils was 90 minutes ( 60120 ) and in sls was 80 minutes ( 60130 ) , p = 0.10 .
for palomo varicocele procedure , sils was performed in three patients ( n = 3 ) , sls in nine patients ( n = 9 ) .
the median cost in sils was  734 ( 532735 ) and in sls was  400 ( 205801 ) , p = 0.07 .
operative time in sils was 60 minutes ( 5060 ) and in sls was 80 minutes ( 55100 ) , p = 0.17 . 

recent publications have established the feasibility of sils in the pediatric population [ 15 ] . however to become a truly established method of performing surgery in children , sils has to be demonstrated to be economically feasible .
we attempted to achieve this by prospectively documenting the consumable cost , times of operation , and demographic data for all laparoscopic procedures and undertaking a comparative assessment of cost and operating time between sils and sls for common pediatric surgery operations .
apart from palomo procedure where costs were higher , sils was found to be more cost - effective than sls in appendicectomy , nephrectomy / heminephrectomy , and ovarian cystectomy / oophorectomy .
however , this did not translate into statistical significance because of the small sample size .
the higher cost of sls was largely due to the use of additional port / ports which were more expensive relative to the cost of the sils port .
once access into the abdomen was achieved , instrument and haemostatic devices use was broadly similar .
the higher cost of palomo was a surprise given the simplicity of the procedure , and this is attributed to the inadvertent opening of an ultrasonic haemostatic device in addition to a hemoclip for a single case when just the latter would have sufficed .
given the small number of patients this additional cost for the sils group was sufficient to adversely influence the figures .
operative time in sils was lower than sls for appendicectomy , nephrectomy / heminephrectomy , and palomo procedure . this is due possibly to the fact that all sils procedures were performed by a single laparoscopic surgeon with extensive experience .
a prospective randomized trial from the adult literature has shown that duration of operation is significantly shorter with traditional laparoscopy compared to sils .
currently , prospective randomized trial in children are in progress assessing operative time as a primary outcome variable in these two groups of patients .
initially olympus triport ports were utilized , but this was changed to covidien sils port for two reasons : firstly , standardization of consumable procurement within the department and secondly , an improved gas seal provide by the latter .
generally costs for the sils approach were contained by the use of standard , reusable laparoscopic instruments .
instrument clash is a challenge with straight devices , but the difficulties are not insurmountable and all operations were completed without conversion .
clearly roticulating and curved instruments or even magnetic graspers while improving ergonomics and maneuverability when used with sils , require practice to master and involve significant additional costs [ 9 , 10 ] .
hansen et al . , in his series of 224 sils in children , reported at least 21% of operations requiring one additional port even for commonly performed operations like appendicectomy . in our series ,
none of the sils cases required additional ports . although not the subject of this study , it is possible that there are other indirect cost benefits of the sils approach , namely , an improved pain experience and thus analgesic usage from the use of fewer ports and cost savings from earlier hospital discharge . additionally , there are clear benefits to the national economy from earlier return to work . in conclusion , sils appears to be cost - effective and safe for common pediatric surgical operations .
there are no significant differences in operating time compared to standard laparoscopy in this series , but we are limited by a small sample size .
the aim of the study was to review our experience with single - incision laparoscopic surgery ( sils ) and to compare costs and operative time to standard laparoscopic surgery ( sls ) . 
 a prospectively collected database of operative times and costs was analysed for the years 20082011 . 
 sils cases were compared to standard laparoscopy on a procedure - matched basis . 
 patient demographics , on - table time and consumable costs were collated . 
 descriptive statistics and mann - whitney u - test were utilized with spss for windows . 
 analysis of the data demonstrate that neither consumable costs nor operative time were significantly different in each group . comparing operative costs , sils appendicectomy , nephrectomy / heminephrectomy , and ovarian cystectomy / oophorectomy showed cost benefit over sls (  397 versus  467 ;  942 versus  1127 ;  394 versus  495 ) . a trend toward higher cost for sils palomo procedure 
 is noted (  734 versus  400 ) . 
 operative time for sils appendicectomy , nephrectomy / heminephrectomy , and palomo was lower compared to sls ( 60 versus 103 minutes[mins . ] ; 130 versus 60  mins . ; 60 versus 80  mins . ) . in conclusion 
 , sils appears to be cost - effective for the common pediatric surgical operations . 
 there is no significant difference in operating time in this series , but small sample size is a limiting factor . 
 studies with larger numbers will be necessary to validate these initial observations .