PORT SITE INCISIONAL HERNIA AFTER MINIMAL ACCESS SURGERY

Incisional hernia is a common sequel to open abdominal surgery, affecting 5–15% of patients. The introduction of laparoscopic surgery into clinical routine more than 20 years ago has dramatically changed the field of surgery. It is commonly held that the frequency of incisional hernia has been reduced since the introduction of minimal access surgery. The incidence of port site hernia ranges from 1% to 6%. The aim of this study is to identify most common causes of port site incisional hernia. This is a retrospective study of 2116 patients who underwent laparoscopic surgery between January 2006 and December 2010. The information obtained according to indication of surgery, onset of hernia, clinical risk factors for incisional hernia like age& sex, BMI, co-morbidity, and those related to surgical factors such as port site, port size, port site infection and abdominal access techniques. The data were retrieved for patients who developed port-site incisional hernia (PSIH). The incisional hernia rate for the entire series was 2.5%. Most port site hernias developed in the 10 mm port, in the umbilical and supra umbilical, midline and 0% for the off-midline. There was statistically significant difference in patient’s related risk factors regarding age, BMI and wound infection with development of port site hernias. Conclusion: In this series, the 10mm port in midline site is a significantly higher cause for incisional hernia than the off-midline and smallest port size. Open first access technique, obesity and port site infection also significantly increase the incidence of port site incisional hernia. Introduction ncisional hernia is a bulge or protrusion that occurs near or directly along prior abdominal surgical incision, it can occur at the site of any type of abdominal surgery from the breastbone down to the groin 1,2 . Incisional hernia is a common sequel to open abdominal surgery, affecting 5–15% of patients. The reported prevalence of this complication varies between studies, depending upon the type of incision employed, the patient group studied, and the duration of follow-up 3-5 . The introduction of laparoscopic surgery into clinical routine more than 20 years ago has dramatically changed the field of surgery. An abundance of case studies, randomized controlled trials and several carefully performed meta-analyses have demonstrated the advantages of this new technique on the highest level of evidence-based medicine 4,6,7 . Patients undergoing laparoscopic operations have less postoperative pain, less impairment of vital functions, a shorter hospital stay and they resume usual activities more rapidly 6,7 . Laparoscopy is said to be the third patient-friendly revolution in medicine following the introduction of asepsis and anesthesia. It is commonly held that the frequency of incisional hernia has been reduced since the introduction of minimal access surgery. Although there have been a number of case reports describing herniation at I Port site incisional hernia after minimal access surgery Sadiq Kassim Jassim, Prof. Mazin ALHawaz & Jasim D. Saod Bas J Surg, September, 17, 2011 38 laparoscopic trocar sites 6-10 , there have been surprisingly few studies 11,12 examining the exact frequency of this complication after laparoscopic surgery. These studies show that the incidence of port site hernia ranges from 1% and 6%. Fear 13 first reported a trocar site hernia in his large series on laparoscopy in gynecological diagnosis. Crist and Gadacz 14 defined port site hernia as the development of a hernia at the cannula insertion site, and this term has also been used in other articles. Classification: Hitoshi Tonouchi et al 15 classify trocar site hernias into 3 types according to the reported cases ( Figure 1). Early-onset type indicates dehiscence of the anterior fascial plane, posterior fascial plane and peritoneum. The early-onset type was recognized in many case reports as beginning to develop in the early stages after surgery, often presenting as a smallbowel obstruction. Figure 1: Classification of the 3 trocar site hernias. A, Normal stab wound of trocar site. B, Earlyonset type: dehiscence of anterior and posterior fascial plane and peritoneum. C, Late-onset type: dehiscence of anterior and posterior fascial plane. Peritoneum constitutes hernia sac. D, Special type: dehiscence of whole abdominal wall. Protrusion on intestine and/or omentum.(Hitoshi Tonouchi et al: Trocar Site Hernia Arch Surg. 2004;139:1248-1256). The late-onset type indicates dehiscence of the anterior fascial plane and posterior fascial plane. The hernia sac of late-onset type is the peritoneum. The late-onset type has often been recognized, in many large series, to be related to complications of the trocar insertion. Late-onset type hernias almost always develop in the late stages several months after surgery. The special type indicates dehiscence of the whole abdominal wall. Protrusion of the intestine and other tissue (eg, greater omentum) is recognized. The first case, reported by Fear 13 was of the special type: a loop of the bowel came through a defect as the laparoscope and sheath were withdrawn. Therefore, this first report points us toward expressing a protrusion of the bowel and/or omentum as a "hernia," although in this type there is no hernial sac. Three case reports of the special type have been published since then 16-18 . We can diagnose the special type without any modalities. With the early-onset type we are able to locate the site of incarceration by computed tomography and surgically reduce and repair the hernia with minimal enlargement of the puncture wound, thus avoiding a full laparotomy 19 . Port site incisional hernia after minimal access surgery Sadiq Kassim Jassim, Prof. Mazin ALHawaz & Jasim D. Saod Bas J Surg, September, 17, 2011 39 An unknown proportion of asymptomatic patients do not get physically examined 20 , although asymptomatic lumps are sometimes found in late-onset–type hernias. There have been no reports on whether such insidious trocar site hernias in asymptomatic patients are worthy of any further examination 20 . In general the factors influencing healing of a wound 26 : Site of the wound, Structures involved, Mechanism of wounding (Incision, Crush, Crush avulsion), Contamination (Foreign bodies, bacteria), Loss of tissue. Other local factors: Vascular insufficiency (arterial or venous), Previous radiation, Pressure. Systemic factors: Malnutrition or vitamin and mineral deficiencies, Disease (e.g. diabetes mellitus), Medication (e.g. steroids), Immune deficiencies [e.g. chemotherapy, acquired immunodeficiency syndrome (AIDS)] &Smoking. Aim of Study The aim of this study is to identify most common cause of port site incisional hernia regarding the port site, port size, first port access (close versus open), port closure or not and port site infection as local causes and Body Mass Index (BMI), immunosuppressants and smoking as a general factors. Patients & methods Study Design This is a retrospective analysis where the required information collected from medical records of 2116 patients who underwent laparoscopic procedures for different indications under the care of a multiple consultant surgeons in the department of surgery Basrah General Hospital between January 2006 and December 2010. The information was obtained regarding the indication of surgery, onset of hernia, clinical risk factors for incisional hernia like age ,sex, BMI, smoking and co-morbidity, and those related to surgical factors such as port site, port size, port site infection and abdominal access techniques. Both open and closed technique was used to create the pneumoperitoneum in all patients. In our hospital we used 5-mm and 10-mm ports and a 3-edged reusable trocar for creation of ports. The data were retrieved for patients who developed port-site incisional hernia (PSIH). The analysis and follow-up of these complications are reported here in. Selection Criteria All patients who underwent laparoscopic surgery under the care of any laparoscopic surgeon in our hospital were included in this study regardless of American Society of Anesthesiology grading, body mass index, type of procedure, sex and age of the patient. Abdominal Access Pneumoperitoneum created by closed access technique was the practiced way of access by some surgeons in our hospital. Open fielding technique involves a small incision over the everted umbilicus at a point where the skin and peritoneum are adjacent were advocated by other surgeons. Palmer’s technique (a small incision is made to allow the insertion of first port through left sub-costal margin) was the first access in patients underwent venteral hernia repair laparoscopically. The site for secondary port inset under direct vision, transillumination with illuminated telescope tip was done first to locate avascular area to avoid injury of subcutaneous vessels. Port site and size Transverse or vertical 1-1.2 cm midline incision in inferior or superior crease of umbilicus and transumbilical were used as first access in some patients and supra umbilical off midline (just right to midline) and Palmer’s incisions were used in others. Secodary port were put in epigastrium 10 mm also in some patients transverse and vertical in other, in mid line or just right to mid line. All 5 mm ports were inserted laterally in all patients. Port site incisional hernia after minimal access surgery Sadiq Kassim Jassim, Prof. Mazin ALHawaz & Jasim D. Saod Bas J Surg, September, 17, 2011 40 Withdrawal of instruments and ports: Once the surgery is finished, all the instruments were removed carefully under vision. All the accessory ports were also removed and the gas was removed by releasing the valve of 10 mm cannulas. The primary port was taken out at last, when telescope introduced in and the cannula is pulled over telescope to prevent suction of omentum or bowel. Port closure Technique The ports were cleaned with 10% povidone iodin


Introduction
ncisional hernia is a bulge or protrusion that occurs near or directly along prior abdominal surgical incision, it can occur at the site of any type of abdominal surgery from the breastbone down to the groin 1,2 .Incisional hernia is a common sequel to open abdominal surgery, affecting 5-15% of patients.The reported prevalence of this complication varies between studies, depending upon the type of incision employed, the patient group studied, and the duration of follow-up [3][4][5] .The introduction of laparoscopic surgery into clinical routine more than 20 years ago has dramatically changed the field of surgery.An abundance of case studies, randomized controlled trials and several carefully performed meta-analyses have demonstrated the advantages of this new technique on the highest level of evidence-based medicine 4,6,7 .Patients undergoing laparoscopic operations have less postoperative pain, less impairment of vital functions, a shorter hospital stay and they resume usual activities more rapidly 6,7 .Laparoscopy is said to be the third patient-friendly revolution in medicine following the introduction of asepsis and anesthesia.It is commonly held that the frequency of incisional hernia has been reduced since the introduction of minimal access surgery.Although there have been a number of case reports describing herniation at I laparoscopic trocar sites [6][7][8][9][10] , there have been surprisingly few studies 11,12 examining the exact frequency of this complication after laparoscopic surgery.These studies show that the incidence of port site hernia ranges from 1% and 6%.Fear 13 first reported a trocar site hernia in his large series on laparoscopy in gynecological diagnosis.Crist and Gadacz 14 defined port site hernia as the development of a hernia at the cannula insertion site, and this term has also been used in other articles.Classification: Hitoshi Tonouchi et al 15 classify trocar site hernias into 3 types according to the reported cases ( Figure 1).Early-onset type indicates dehiscence of the anterior fascial plane, posterior fascial plane and peritoneum.The early-onset type was recognized in many case reports as beginning to develop in the early stages after surgery, often presenting as a smallbowel obstruction.The late-onset type indicates dehiscence of the anterior fascial plane and posterior fascial plane.The hernia sac of late-onset type is the peritoneum.The late-onset type has often been recognized, in many large series, to be related to complications of the trocar insertion.Late-onset type hernias almost always develop in the late stages several months after surgery.The special type indicates dehiscence of the whole abdominal wall.Protrusion of the intestine and other tissue (eg, greater omentum) is recognized.The first case, reported by Fear 13 was of the special type: a loop of the bowel came through a defect as the laparoscope and sheath were withdrawn.Therefore, this first report points us toward expressing a protrusion of the bowel and/or omentum as a "hernia," although in this type there is no hernial sac.Three case reports of the special type have been published since then [16][17][18] .We can diagnose the special type without any modalities.With the early-onset type we are able to locate the site of incarceration by computed tomography and surgically reduce and repair the hernia with minimal enlargement of the puncture wound, thus avoiding a full laparotomy 19 .
An unknown proportion of asymptomatic patients do not get physically examined 20 , although asymptomatic lumps are sometimes found in late-onset-type hernias.There have been no reports on whether such insidious trocar site hernias in asymptomatic patients are worthy of any further examination 20 .In general the factors influencing healing of a wound 26

Aim of Study
The aim of this study is to identify most common cause of port site incisional hernia regarding the port site, port size, first port access (close versus open), port closure or not and port site infection as local causes and Body Mass Index (BMI), immunosuppressants and smoking as a general factors.

Study Design
This is a retrospective analysis where the required information collected from medical records of 2116 patients who underwent laparoscopic procedures for different indications under the care of a multiple consultant surgeons in the department of surgery Basrah General Hospital between January 2006 and December 2010.The information was obtained regarding the indication of surgery, onset of hernia, clinical risk factors for incisional hernia like age ,sex, BMI, smoking and co-morbidity, and those related to surgical factors such as port site, port size, port site infection and abdominal access techniques.Both open and closed technique was used to create the pneumoperitoneum in all patients.In our hospital we used 5-mm and 10-mm ports and a 3-edged reusable trocar for creation of ports.The data were retrieved for patients who developed port-site incisional hernia (PSIH).The analysis and follow-up of these complications are reported here in.Selection Criteria All patients who underwent laparoscopic surgery under the care of any laparoscopic surgeon in our hospital were included in this study regardless of American Society of Anesthesiology grading, body mass index, type of procedure, sex and age of the patient.

Abdominal Access
Pneumoperitoneum created by closed access technique was the practiced way of access by some surgeons in our hospital.Open fielding technique involves a small incision over the everted umbilicus at a point where the skin and peritoneum are adjacent were advocated by other surgeons.Palmer's technique (a small incision is made to allow the insertion of first port through left sub-costal margin) was the first access in patients underwent venteral hernia repair laparoscopically.The site for secondary port inset under direct vision, transillumination with illuminated telescope tip was done first to locate avascular area to avoid injury of subcutaneous vessels.

Port site and size
Transverse or vertical 1-1.2 cm midline incision in inferior or superior crease of umbilicus and transumbilical were used as first access in some patients and supra umbilical off midline (just right to midline) and Palmer's incisions were used in others.Secodary port were put in epigastrium 10 mm also in some patients transverse and vertical in other, in mid line or just right to mid line.All 5 mm ports were inserted laterally in all patients.

Withdrawal of instruments and ports:
Once the surgery is finished, all the instruments were removed carefully under vision.All the accessory ports were also removed and the gas was removed by releasing the valve of 10 mm cannulas.The primary port was taken out at last, when telescope introduced in and the cannula is pulled over telescope to prevent suction of omentum or bowel.

Port closure Technique
The ports were cleaned with 10% povidone iodine solution before closure.At the end of the procedure, the port pressure was released.Closure of the fascial defect and skin were performed for all 10 mm ports in opened techniques and only skin in closed techniques using 2.0 polyglycolic or polydiaxonone (PDS) sutures.The 5 mm ports were not need to be closed.

Port site infections
Port site infection information's were taken from patients whom developed port site hernia, witness of pus inside wound indicate infection.

Statistical Analysis
Data were fed on computer program using SPSS (statistical package for social science-version 11).The results were presented in tables and Chi-square test and Fishers exact test was done.A P ≤ 0.05 was considered to be statistically significant.

Figure 2: The percentage of laparoscopic procedures performed
The mean age of patients was 52 years (range, 17-81).The 54 port-site incisional hernias (PSIH) were subsequently repaired as elective cases.The incidence therefore is 2.5%.Forty seven hernias developed after cholecystectomy and five hernias after diagnostic laparoscopy and two after laparoscopic appendicectmies.No immediate major complications or mortality was reported in relation to port-site hernia complications.The onset of hernia in all laparoscopic procedures was late type (Table I).Taking into consideration the above mentioned risk factors for development of Port Site Incisional Hernia (PSIH), table II showing relationship between surgical factors and developed port site incisional hernia after Minimal Access Surgery (MAS) and its statistical significance and table III showing relationship between clinical risk factors and development of incisional hernia after MAS and its statistical significance.

Discussion
Incisional hernias are a common problem after laparotomy.The incidence ranges from 5% to 15% 3 .Extensive studies have investigated how to repair these hernias after laparotomy (mesh vs no mesh), and recurrences still remain high with mesh repair (up to 20%) 2 .
Since the evolution of laparoscopy, incisional hernia rates have been analyzed for many different surgical procedures (gastrointestinal, gynecologic, and urologic).The incidence of PSIH is variable from center to center, depending on several factors including surgical technique and, of course, surgical experience.Most of the reports discuss port-site hernias, and most conclude that any port-site hernia 10 mm or larger should have closure of the fascia 21,22 .Some also advocate that 5-mm port sites subjected to extensive manipulation should have closure of the fascia as well 22 .In our retrospective study the overall incisional hernia rate was 2.5%, which is well within the reported rates which approximately 1% to 6% of patients [21][22][23][24][25][26][27] .Interestingly, we found that all our incisional hernias were in the midline, possibly because of the absence of supporting muscle.Regarding port size we found that all hernias were develop in 10 mm port.Crist and Gadacz 14 regarded the use of a large trocar as one of the factors predisposing to the development of a hernia.Many authors have mentioned that a direct relationship of trocar size to the risk of subsequent herniation seems reasonable 14 .We also analyzed some of the factors that could play a role in the formation of trocar-site hernias in addition to the trocar site and trocar diameter including: the, the trocar design, preexisting fascial defects, and some operations and patient-related factors like age, wound infection rate, diabetes and other co-morbidity, smoking and BMI.With respect to these risk factors, we found statistically significant difference (p ≤ 0.05) between the midline and off-midline port site, 10 mm trocar size versus 5mm size, obese and non obese patients.It is recommended that all 10 mm trocar sites be closed, incorporating the peritoneum into the fascial closure to obliterate the preperitoneal space.
The thick preperitoneum is a potential space that allows for the development of a Richter hernia despite adequate fascial closure 28- 32 .Many authors believe that inserting the 10-mm lateral trocar in an oblique fashion or as a Z-tract will reduce hernia formation by putting the external and internal fascias at different levels 33,34 .In a randomized, observer-blinded study, Tarnay et al 35 found that blunt conical trocar-cannula systems resulted in significantly smaller fascial defects than the widely used pyramidal and two cutting-dilating trocar-cannula systems.These smaller fascial defects could reduce the risk of incisional hernia and dehiscence.In our study we found that the port site hernias were more in open first access technique (40 vs 14) hernias after open and closed access respectively, although the fascial defects were not closed in the closed technique, closure of these wounds generally is quite difficult and rarely complete due to the small opening of he skin incision.This was in reverse to Mayol et al 36 .In that the incidence of trocar site hernia in closed laparoscopy was higher than in open.Regarding port site we found that most of hernias were develop in umbilical and paraumbilical region and in midline rather than in off midline site, this was the same as with Azurin et al 37 .And Ahmad et al 38 whom reported that an incidental umbilical hernia, which existed preoperatively, lead to a trocar site hernia.Nassar et al 39 also mentioned the incidence of umbilical or paraumbilical fascial defects in 12% of patients who had preoperative laparoscopic cholecystectomy.Plaus 40 mentioned that puncture sites off the midline might be less susceptible to herniation due to the overlapping of muscle and fascial layers.Duron et al 5 reported that the lateral wall is composed of 2 fascial planes and muscle, making it theoretically less prone to dehiscence.There have been two other explanations for this.First, that the frequent use of a large trocar in this area leads to a trocar site hernia in the umbilical and paraumbilical region 18 and second, that the small intestine is less often in contact with a lateral trocar site 5 .Four from total of 54 port site hernias in our series were develop in epigastrium, we thing that the cause was stretching of the Port Site for retrieval of specimens 36 .Nassar et al 39 mentioned the extension of the fascial defect is the most significant risk factor in their prospective study.Kopelman et al 41 emphasized fascial closure in stretching the trocar site, but McMillan and Watt 42 illustrated the need for careful fascial closure of all 10-mm trocar site-related wounds whether or not the gallbladder has been removed through them, and whether or not the wound have been extended.It is certain that forced dilation of the fascial layer is proposed as an etiological mechanism 43 .Duron et al 5 stated that the effects of Compressed Carbon dioxide might push the omentum or intestinal loops through the point of insertion in the fascia.The protruding structures might then be trapped by abdominal muscle contractions 4,9,40 .He was stated that a partial vacuum is created when the port is withdrawn, thus, drawing omentum and intestines into the fascial defect 23 .Regarding patient-related factors and development of port site hernia, in our study although some of these did not reach statistical significance, the morbidly obese are at a high risk for hernias because of their substantially thicker preperitoneal space and elevated intra-abdominal pressure 12 .There was a tendency to improperly close the fascial defect in obese patients.We consider that this technical flaw has had an influence on the high incidence of trocar site hernias in obese patients.A postoperative port site wound infection is one of the factors predisposing the development of a hernia 14,36 .Callery et al 26 reported that most often the umbilical incision is infected in laparoscopic procedures.Late-onset-type trocar site hernias might be related to infection from the stab wound, but there have been no large series reports clarifying any relationship between trocar site hernias and wound infection in digestive surgery.All type of hernias in our study were late in type and all hernias were repaired electively.

Conclusion
In this series, the 10mm port in midline site is a significantly higher cause for incisional hernia rate than the off-midline and smallest port size.Open first access technique, obesity and port site infections also significantly increase the incidence of port site incisional hernia.

Table III : Relationship between clinical risk factors and port site hernia
NS: Not significant (P≥0.05) and S:significant (P≤0.05)