Short Review of Inguinal Hernia

An inguinal hernia is a protrusion of abdominal-cavity contents through the inguinal canal. About 66% of the affected people are symptomatic. This may include pain or discomfort especially with coughing, exercise, or bowel movements. Often it gets worse throughout the day and improves when lying down. A bulging area may occur that becomes larger when bearing down. Inguinal hernias occur more often on the right than left side. The main concern is strangulation, where the blood supply to part of the intestine is hampered. This usually produces severe pain and tenderness at that area.

Risk factors : Smoking, chronic obstructive pulmonary disease, obesity, pregnancy, peritoneal dialysis, collagen vascular disease, and previous open appendectomy, among others. Hernias are partly genetic and occur more often in certain families. It is unclear if inguinal hernias are associated with heavy lifting. Repair may be done by open surgery or by laparoscopic surgery. Laparoscopic surgery generally has less pain following the procedure.

Approach Considerations

The basic surgical principles of laparoscopic repair include the following:
1. No tension technique
2. Appropriate trocar placement and 
3. The use of appropriate size mesh.
4. The number of trocars used and their placement are related to the site of hernia.

Preoperative Preparation

The patient must be free of skin infections and the respiratory function must be evaluated and optimized before the operation. If the hernia contains parts of the gastrointestinal tract such as bowel, appropriate imaging should be performed in order to avoid any intraoperative complications. The patient may be given a bowel preparation prior to surgery.

Anesthesia

General Anesthesia with endotracheal tube is required or even high spinal is also preferred now a days. 

Operative Preparation:

Peri-operative antibiotics should be given according to the most recent national guidelines. The stomach must be decompressed with anaso-gastric tube, a Foley catheter must be placed and stockings are applied. The skin is prepared in a routine manner using antiseptics solutions.

Patient Position:

The patient is placed in the trendlenberg position so as to make bowel fall away from the operative site i.e. pelvic region. Optional left or right tilt can be given if required.

Instruments and Surgeon’s Position:

All devices and instruments needed for the operation must be checked for proper function & insulation. The surgeon’s position must follow the principles of ergonomics in laparoscopic surgery i.e. suitable table height of 0.49*surgeon’s height, placement of monitor at a distance of 5 times its diagonal length and at a height not less than approximately 20cm from his/her visual axis & Surgeon –hernia site- monitor all should be along one axis.

Port positioning:
 
The 10mm optical port for the telescope and the 5mm lateral portsfor operating instruments are placed in position as per the “Baseball-Diamond” principle of port placement put forth by Dr. R. K. Mishra for best egronomical comfort & good exposure, traction, counter traction and good working angles between the instruments. The operating ports need to be placed at a distance not less than 5cm with each other. 

Access to peritoneal cavity

a. For the closed technique:

• Make an incision on the skin, no more than 3mm using a scalpel blade No. 11 at inferior crease of umbilicus.
• Lift the abdominal wall and insert the Veress needle through the incision at a 45o angle to the spine and perpendicular to the lifted abdominal wall. (This will help to point the veress needle towards the sacral promomtary in turns sacral hollow curve such a way that none of the visceral organ gets injured.)
• After you hear the “two click” sounds, confirmation of intra-peritoneal entry is done by irrigation,aspiration and hanging drop tests.

• Make a smiling incision on the inferior crease of umbilicus of 11mm.
• Using Scandivian technique, to gain safe entry to the intra-peritoneal space.
• Insert the cannula using the blunt trocar into the peritoneal cavity
• Secure the port with lateral stay sutures 

When access to peritoneal cavity is achieved:

• Connect the CO2 either to the Veress needle (for closed technique) or the port (for open technique)
• Begin inflating the intra-peritoneal space according to the principles of insufflation.
• Observe the rise of the intra-abdominal pressure and the total volume of gas as the abdomen and hernia gets distended.
• For the closed technique, after the intra-abdominal pressure reaches the preset pressure of 12-15mmHg,
• Take theveress needle out of the abdomen
• Enlarge the incision up to 11mm and
• Slowly screw the cannula with the trocar into the peritoneal cavity in perpendicular direction. (Insufflation will avoid the possible visceral injury due toperpendicular entry.) 
• The camera is white-balanced and focused. The telescope is then advanced down through the umbilical port into the abdominal cavity under direct vision.
• All four quadrants of the abdomen are examined for any possible accidental pathological findings, if present.
• Then locate the site of action. It is the inguinal region either right or left or both depending upon the defect site/sites.
• Considering the Baseball Diamond concept, put two 5mm operating ports on either side of optical umbilical port under direct vision from inside eliminating the injury to the inferior epigastric vessels by tras-illumination.
• Once, all ports are in position, the hernia and its contents are evaluated.
• Additional unrecognized hernia defects may be found.

Surgical Procedure

• Adhesiolysis, if required is done and contents of the hernia sac are reduced. Make wise use of energy sources if required.
• Now start the peritoneal dissection laterally from a distance of 6 cm at 2 O’clock position for right inguinal hernia & at 10 O’clock position for left inguinal hernia.
• Hold the peritoneum by Maryland or atraumatic grasper, lift it, take a cut with scissor at desired point.
• Then lift the leaf of peritoneum & start bluntly dissecting the peritoneum using scissor.
• Do only peritoneal dissections lateral tomedial.
• Dissect till you reach above the defect.
• Don’t dissect sac at this point.
• Then start from median umbilical ligament go laterally.
• While dissecting the peritoneum, push the fat towards the anterior abdominal wall so that the vital structures present in the pre-peritoneal fat may fall away from the peritoneum assuring their safety.
• Also the only peritoneal dissection leads to less bleed.
• Once done with the lateral & medial dissections, start dissection of sac with upward & backward traction of sac.
• Special precautions should be taken while dissecting over triangle of doom, triangle of pain & trapezoid of disaster. 
• While dissecting the sac, good differentiation should be sought between sac & pseudo-sac. Pseudo-sac is the transvesalisfasia which may be tractioned upwards leading to pulling up of testis.
• If this happens, assistant should be asked to keep a hold of testis in scrotum & then carefully dissect the sac from pseudo-sac.
• Use of energy sources in the area of triangle of doom should be very carefully monitored.
• Medial dissection should be done upto the visualization of Cooper’s ligament.

Mesh Placement: 

• Prolene mesh – 10*15 cm.
• Make sure for sufficient area is dissected to place the mesh of appropriate size.
• This mesh covers all the hernia sites i.e. Deep inguinal ring, Hasselbach’s triangle, Obturator canal & Femoral ring
• Now make a roll of mesh outside the abdomen. 
• Hold the mesh with a needle holder with a 10 to 5mm reducer previously loaded over the shaft.
• Pull the mesh within the reducer.
• Then introduce the mesh assembly through the 10 mm optical port.
• Now put the telescope in and unroll the mesh under vision.
• First fix the medial corner of the mesh to the cooper’s ligament using either non-absorbable suture material or tackers. 
• Now the mesh is well placed in position.
• If required, mesh can be fixed at the periphery at multiple sites avoiding the delicate areas of triangle
• Of doom, triangle of pain & trapezoid of disaster.
• So it is always better to fix only on the aanterior abdominal wall & inguinal ligament.
• There is also another school of thoughts which say “NO FIXATION IS BETTER FIXATION”.
• Once the mesh is placed, then the over lying dissected peritoneum is resutured using vicryl or fixed with tackers.
• Before moving out the telescope the port entry sites are examined for bleeding.
• Optical port is sutured by placing suture within & out under vision using veress needle or a trans-fascial needle.
• Pneumoperitoneum is relieved.
• Cannula is removed with telescope within so as to make it sure that neither the bowel nor the omentum had entered the port wound.
• Knot is tightened after removal of cannula.
• Skin is sutured using ethiprime 3-0 at all port sites.
• Skin around the sutured wound is cleaned with the antiseptic solution.
• Dry sterile dressings are applied to the entry sites.
 
Postoperative Care

• Remove the nasogastric tube when the patient gains consciousness.
• Remove the Foley’s catheter when the patient is able to void urine of his own.
• Administer appropriate antibiotic, analgesic, PPI, anti-emetics & I.V. fluids as required.
• Advance to oral diet as tolerated by the patient, starting with fluids within 1 day

Complications:

• There are no possible complications if every precaution stated above is very well taken care of.
• Postoperatively, some patients develop prolonged ileus which is usually managed conservatively. 
• Surgical-site infections are rare but if developed, they might require the removal of the mesh.
• Serum accumulation in the previous hernia sac is common. Aspiration is not advocated as it may lead to implantation of nidus for infection. It may resolve of its own in few days.
• Some patients may complain of pain at the fixation sites that may too resolve in few days.
• Discomfort of mesh may be sometimes felt which goes off on its own as the fibrosis occurs.

Bibliography - Internet Sources

1. Task Analysis of Laparoscopic procedures, from World Laparoscopy Hospital Website
2. Guidelines for laparoscopic inguinal hernia repair, SAGES. from:
 https://www.sages.org/publications/guidelines/guidelines-for-laparoscopic-inguinal-hernia-repair/
3. Laparoscopic Inguinal Hernia Repair, WebSurg. Mar 2014; 14(03) Retrieved from:
http://www.websurg.com/Laparoscopic_inguinal_hernia_repair_(LVHR)-vd01en4221.htm 
4. Laparoscopic Inguinal Hernia Repair Technique, Medscape. Retrieved from: http://emedicine.medscape.com/article/1892407-overview
5. Robert M. Zollinger& E. Christopher Ellison (2011), Zollinger’s Atlas of Surgical Operations
6. Richard L. Whelan, James W. Freshman & Dennis L. Fowler (2006), The SAGES Manual: Perioperative Care In Minimally Invasive Surgery