1. Laura Withers, M.D. St. Luke’s Roosevelt Grand Rounds July 6, 2005
Incisional Hernias
Laura Withers, M.D.
St. Luke’s Roosevelt Grand Rounds
July 6, 2005

2. Anatomy of the Abdominal Wall
Superior to the arcuate line
Inferior to the
arcuate line

3. Definition
A hernia is the protrusion of an organ through the wall that normally contains it. An incisional hernia occurs in the area of an old surgical scar. A ventral hernia occurs in the abdominal wall.

4. A Problem Encountered and Produced by Surgeons:
In the U.S. approximately 2 million laparotomies are performed each year.
The incidence of incisional hernias is reportedly between 3%-20% . This results in an estimated 60, ,000 ventral hernia repairs per year.
No repair, approach or material has become a gold standard in the treatment of this problem.

5. Clinical Presentation
More than half of incisional hernias occur within the first two years after primary operation.
A diffuse bulge directly under or adjacent to a previous incision.
Increased protrusion with valsalva or standing.
Cosmetic concerns or interference with work or activity are common complaints.
Pain is unusual as a presenting symptom unless there are incarcerated or strangulated structures.
The natural history of an incisional hernia is to enlarge and become symptomatic.

6. Clinical Presentation and Workup
Physical exam may not be adequate in obese patients, patients with significant rectus diastasis, patients with laxity due to spinal injury or patients who have had multiple prior abdominal surgeries. In this case UGI, ultrasound or CT may be used.

7. Risk Factors Age Above 65 or 70 Male Gender Malnutrition Sepsis Anemia
Uremia
Ascites / Liver Failure
Diabetes
Pulmonary Disease
Smoking
Abdominal Distension
Obesity
Coughing / Retching
Urinary Retention
Post-op Ileus
Peritoneal Dialysis
Wound Infection
Corticosteroids
Chemotherapy
Immunosupression

8. Etiology
Mechanical Factors – Intra-abdominal pressure overwhelming a weakness in the abdominal wall.
Pathologic changes in collagen that adversely affect wound healing.
Type I collagen is dominant in a mature scar
Type III collagen dominates in the early stages of wound healing
Factors such as smoking, malnutrition, immunocompromise, wound infection and underlying diseases are now understood to interfere with normal collagen metabolism.

9. Prevention of Incisional Hernias “The strength of a wound lies in the musculoaponeurotic layer.”
Oblique or transverse incisions are preferred in many cases
because the pull of the lateral abdominal wall muscles is parallel to the incision and there is less distracting tension than that on vertical incisions.
because the tension on the suture lies perpendicular to the orientation of fibers in the abdominal wall fascia. Thus the suture is less likely to pull through.

10. Kocher or Right Subcostal Incision: oblique abdominal incision paralleling the thoracic cage on the right of the abdomen for cholecystectomy.
Pfannenstial Incision: A transverse incision through the external sheath of the rectus muscles, about an inch above the pubes. It follows natural folds of the skin and curves over mons pubis in such a way that the pubic hairs cover the scar.
Rocky-Davis Incision: muscle splitting transverse abdominal incision employed in appendectomy.
Abdominal incisions are based on anatomical principles
They must allow adequate assess to the abdomen
They should be capable of being extended if required
Ideally muscle fibres should be split rather than cut
Nerves should not be divided
The rectus muscle has a segmental nerve supply
Principles for making abdominal incisions
It can be cut transversely without weakening a denervated segment
Above the umbilicus tendinous intersections prevent retraction of the muscle

11. The Paramedian Incision
The paramedian incision is a vertical incision made parallel to and approximately 3 cm from the midline
Rectus - retracted laterally
The potential advantages of this incision are:
The rectus muscle is not divided
The incisions in the anterior and posterior rectus sheath are separated by muscle
The incision is closed in layers –peritoneum and posterior sheat the anterior sheath
Lower incidence of incisional hernia

12. Midline Incision: The most common and most versatile approach. Closure
2 No. 1 continuous polypropolene sutures that meet in the middle
Bites incorporating all layers of the abdominal wall except skin and fat - no need to close the peritoneum
Midline incisions are the commonest approach to the abdomen
The following structures are divided:
Skin
Linea alba
Transversalis fascia
Extraperitoneal fat
Peritoneum
The incision can be extended by cutting through or around the umbilicus
Above the umbilicus the Falciform ligament should be avoided
The bladder can be accessed via an extraperitoneal approach through the space of Retzius
The wound can be closed using a mass closure technique
The most popular sutures are either non-absorbable or absorbable monofilaments
At least 1 cm bits should be taken 1 cm apart
Requires the use of one or more sutures four times the wound length
A paramedian incision is made parallel to and approximately 3 cm from the midline
The incision transverse:
Anterior rectus sheath
Rectus - retracted laterally
Posterior rectus sheath - above the arcuate line
The potential advantages of this incision are:
The rectus muscle is not divided
The incisions in the anterior and posterior rectus sheath are separated by muscle
The incision is closed in layers
Takes longer to make and close
Had a lower incidence of incisional hernia (when sutures were not so good)

13. Suture Characteristics
Nonabsorbable suture has better tensile strength but can persist and become a focus of infection or a draining sinus tract
Monofilaments and inert materials are less likely to be associated with wound infection
Braided materials knot more securely than monofilament and are less likely to stretch
“Memory” describes a stitches tendency to straighten over time loosening and slipping. It is overcome by tying square knots and using an adequate number of throws.

14. Suture Techniques “ One centimeter back and one centimeter apart.”
Bite – to prevent the suture from pulling through it should be placed at least 1 cm from the wound edge
Spacing – to distribute the tension on the tissues while also preventing herniation between the sutures stitches are placed about 1 cm apart
Continuous vs. Interrupted Sutures – continuous suturing may better distribute the tension but if one bite pulls loose it compromises the whole closure
Tension Sutures – Full thickness sutures that help prevent dehisance in cases of difficult abdominal closure

15. Prevention of Trocar Site Hernias
The incidence of trocar site hernia has been shown to be 0.65% to 2.80%
midline, periumbilical port sites greater than 5 cm and made with bladed introducers often result in incisional hernia if not closed.

16. Port Site Closure Technique

17. Indications for Incisional Hernia Repair
The presence of the hernia is indication for repair in patients able to tolerate surgery.
Strangulation and acute incarceration are indications for urgent operation.
Incarceration – Occurs in about (6-15%) of incisional hernias
Strangulation – Occur in about 2% of all incisional hernias

18. Principles of Repair Tension Free Repair
Incision - Chosen to Provide Good Exposure of the Defect
Do Not Expose Bowel to Reactive Mesh
Clear Adequate Margins of the Defect
Skin Hygiene
Antibiotic Prophylaxis
Choice of Anethesia
Avoid Counter-incisions
When to Excise the Sac

19. Direct Open Repair “Pants over Vest”

20. Direct Open Repair
Other techniques for open, primary repair include simple interrupted or continuous suturing of the fascial edges or the use of mattress, figure of eight or even internal retention sutures.
Direct repair is reserved for small defects with the upper size limit cited as being between 3 and 5 cm.
Even in small hernias recurrence rates of up to 50% have been reported with these techniques.

21. Direct Open Repair For Larger Defects

22. Open Onlay Mesh Repair

23. Open Inlay Mesh Repair

24. Rives-Stoppa Technique

25. Intraperitoneal Underlay Mesh Repair
Pascal's principle—wide mesh overlap of defect distributes pressure equally over larger surface area.

26. Laparoscopic Repair Set Up and Trocar Sites

27. Laparoscopic Hernia Reduction and Adhesiolysis
Hernia contents are gently reduced using broad grasping instruments. External counter-pressure aids the reduction.

28. The extent of the defect is assessed.
The margins of the defect may be marked on the skin. The patch is measured and trimmed to fit. With the smooth side down, 4-6 large fixation sutures are placed around the patch and tied

29. Laparoscopic Mesh Insertion

30. Laparoscopic Mesh Fixation

31. A Few Mesh Materials
Vicryl (polyglactin 910) woven mesh is prepared from a synthetic absorbable copolymer of glycolide and lactide, derived respectively from glycolic and lactic acids. It is absorbable and reactive.
Marlex, also known as Prolene - Polypropylene non-absorbable, non reactive monofilament.
Polyester Fiber Mesh is nonabsorbable, knitted, flexible and durable. It has a high degree of porosity that allows tissue ingrowth.
Polytetrafluoroethylene (PTFE) and expanded polytetrafluoroethylene (ePTFE) carbon and fluorine based synthetic polymers that are biologically inert and non-biodegradable in the body. ePTFE is more commonly known by the brand names Gore-Tex® and SoftForm.

32. Mesh Products by Bard
Bard Composix E/X mesh is designed for laparoscopic ventral hernia repair. Its low profile makes it easy to manipulate, and its sealed edge eliminates exposed mesh along the perimeter.
The Bard Composix Kugel patch has a "memory recoil ring" which helps the patch to maintain its shape during placement.
The Bard Ventralex patch is designed for open repairs of defects 4 cm or less. The positioning pocket and straps facilitate placement.

33. Mesh Products by Ethicon
ULTRAPRO* is Partially Absorbable Mesh - the only one in the US. It culminates a natural evolution in mesh repair toward lighter, absorbable material. So it forms a flexible scar
PROCEED* Surgical Mesh also has two layers, a thin, bioresorbable layer that separates its strong, supportive mesh from underlying viscera. It is a lightweight construction to improve handeling for laparoscopic procedures. It has a special deploying tool.

34. Mesh Products by Gore
GORE MYCROMESH® PLUS Biomaterial has antimicrobial technology. This ePTFE biomaterial contains silver carbonate and chlorhexidine diacetate, which inhibit bacterial colonization on the patch for up to 10 days post-implantation.
GORE DUALMESH is a soft, ePTFE that has two functionally distinct surfaces: a closed structure surface for reduced tissue attachment and a macroporous structure surface for faster tissue attachment

35. Complications of Incisional Hernia Repair
Enterotomy
Wound Infection
Mesh Infection
Persistent seroma
Prolonged Pain
Ileus
Bleeding/Hematoma
Recurrance
Respiratory Distress
Abdominal Compartment syndrome or IVC compression

36. Algorithm For Enterotomy During Laproscopic Incisional Hernia Repair
YES
Repair and proceed
Spillage? No No
Laparoscopic repair possible?
YES
Open to repair and complete adhesolysis
Repair laproscopically and complete adhesolysis
No Mesh Placement. Staged repair to be completed in several days to weeks

37. Wound and Mesh Infection Is mesh was just a large foreign body in an otherwise clean surgical wound?
many wounds are inflamed but not necessarily infected
infected wounds need to be opened
avoid exposing the underlying mesh if possible
infections that involve polypropylene meshes can be managed with surgical drainage, excision of exposed, segments and antibiotics
Meshes (ePTFE) require removal in most cases because they lack tissue ingrowth that could combat the infection

38. Seroma
The development of seroma is virtually guaranteed after lap incisional hernia repair and probably after repair with mesh in general. They typically resolve spontaneously without intervention and are not considered a complication unless they are clinically apparent more than 8 weeks postoperatively.

39. Complications: Prolonged Pain
In Rives-Stoppa or other open mesh implantation it occurs in more than 10% of patients
Transabdominal suture site pain after laparoscopic ventral hernia repair occurs in 1% to 3% of patients.

40. Contraindications to Lap Incisional Hernia Repair
Major loss of abdominal domain
Severe debilitation
Fewer than 5 years life expectancy
Respiratory distress
Pregnancy
Portal hypertension
Renal failure with presence of peritoneal dialysis catheter

41. Possible Advantages of Laparoscopic Repair
Minimization of soft-tissue dissection
To visualize much of the abdominal wall leads to fewer missed hernias
In obese patients
Recurrent hernias- Avoids dissection through the previous operative site.

42. Comparison studies of laparoscopic and open ventral hernia repairs
Wound infection
Recur
Name
Year
McGreevy [48]
2003 65 71 5 15 2 7 —
Raftopoulos [49] 50 22 14 10 1 4
Wright [50]
2002 90 31 8
Robbins [51]
2001 18
DeMaria [36]
2000 21 13
Chari [52]
Carbajo [35]
1999 30 20 6 3
Ramshaw [33] 79
174 46 36
Park [23]
1998 56 49 17
Holzman [53]
1997 16
Percent
23.2
30.2
2.0
3.5
2.6
5.8
4.0
16.5
# of patients Morbidity Mesh Infxn
Lap open lap open lap O L O L O

43. Comparing Laparoscopic to Open: Prospective Studies
Two prospective studies comparing laparoscopic ventral hernia repair with open:
Carbajo et al Surg Endosc. 1999
DeMaria et al Surg Endoscopy 2000
They support the advantages purported by the previous studies
A design for a prospective, randomized multicenter study organized by Dr. Itani from Harvard was published in AJS in Dec
It is comparing laparoscopic repair with the Chevrel primary repair with mesh onlay and hypothesizes that the laparoscopic group will have fewer complications at 8 weeks post op

44. St Luke’s-Roosevelt

45. References
Read RC, Yoder G. Recent trends in the management of incisional herniation. Arch Surg 1989;124:485-8.
Bucknall TE, BMJ 1982;284:931-3
Manninen MJ, Lavonius M, Perhoniemi VJ. Results of incisional hernia repair: a retrospective study of 172 unselected hernioplasties. Eur J Surg 1991;157:29-31.
Bucknall TE, Burst Abdomen and incisional hernia: a prospective study of 1129 major laparotomies. BJM 182;284: Pollack AV, Single-layer mass closure of major laparotomies by continuous suturing. J R Soc MED 1979;72:889-93
Carlson MA, Ludwig KA, Condon RE. Ventral hernia and other complications of 1,000 midline incisions. South Med J 1995;88:450-3.
Mastery of Surgery Dr. Penn and Dr. Baker
Gabbe: Obstetrics - Normal and Problem Pregnancies, 4th ed., Copyright © 2002 Churchill Livingstone, Inc
Nonclosure of peritoneum: a reappraisal. Tulandi T - Am J Obstet Gynecol - 01-AUG-2003; 189(2):
Tonouchi H. Ohmori Y. Kobayashi M. Kusunoki M. Trocar site hernia. [Review] [63 refs] [Journal Article. Review. Review of Reported Cases] Archives of Surgery. 139(11): , 2004 Nov.
The 2-mm trocar: a safe and effective way of closing trocar sites using existing equipment.Reardon PR - J Am Coll Surg - 01-FEB-2003; 196(2):
Liu CD, McFadden DW. Am Surg 2000;66:853-4.
Bowrey DJ, Blom D, Crookes PF, et al. Risk factors and the prevalence of trocar site herniation after laparoscopic fundoplication. Surg Endosc 2001;15:663-
•.Garzotto MG, Newman RC, Cohen MS, et al. Closure of laparoscopic trocar sites using a spring-loaded needle. Urology 1995;45:310-2.
Umbilical and epigastric hernia repair.    Muschaweck U - Surg Clin North Am - 01-OCT-2003; 83(5):

46. References
Luijendijk RW, Hop WC, van den Tol P, DeLange DC, Braaksma MM, Ijzermans JN, et al. A comparison of suture repair with mesh repair for incisional hernia. N Engl J Med 2000;343:392-8
Incisional Hernia Repair Millikan KW - Surg Clin North Am - 01-OCT-2003; 83(5):
Toy FK, et al Prospective, Multicenter Study of Laparoscopic Ventral Hernioplasty: Surg Endos 1998; 12(7):955-9.
Park, A. Laparoscopic Ventral Hernia Repair. Advances in Surgery
Laparoscopic repair of incisional hernias. Cobb WS - Surg Clin North Am - 01-FEB-2005; 85(1): , ix
Complications of open groin hernia repairs.Stephenson BM - Surg Clin North Am - 01-OCT-2003; 83(5):
DeMaria et al Laproscopic intraperitoneal PTFE patch repair of ventral hernia. Surg Endoscopy 2000
Carbajo et al Laparoscopic treatment vs Open Surgery in the solution of major incisional and ventral hernias with mesh Surg Endosc. 1999

48. On the Horizion?
A study by Dubay et al in the anals of surgery June 2004 shows reduced recurrance rates when abdominals incisions are treated with basic fibroblast growth factor
Advances in mesh technology : those such as that decrease adhesions or those that allow or even stimulate tissue regeneration or those that have improved resistance to infection.
Randomized, Prospective studies that may provide guidance in choosing the proper procedure based on patient characteristics.
Innovations to help those of us on the learning curve of laparoscopy

49. Wound matrix deposition over time
Wound matrix deposition over time. Fibronectin and type III collagen constitute the early matrix. Type I collagen accumulates later and corresponds to the increase in wound tensile strength.
Collagen is the principal structural protein of most tissues of the body. Normal tissue repair depends on collagen synthesis, deposition, and cross-linking. Fibroblasts synthesize and deposit collagen compounds as early as 48 hours after injury. Immature collagen is highly disorganized because it exists in a gel-like consistency.
After a series of enzymatic processes, characteristic fibrils are produced. Subsequent intermolecular cross-links are responsible for a major portion of the strength of the collagen fibril. The entire process depends on tissue lactate and ascorbic acid and is directly related to tissue arterial carbon dioxide partial pressure (PaO2 ). In the absence of vitamin C, prolyl and lysyl hydroxylase will not activate, and oxygen will not be transferred to proline or lysine. Underhydroxylated collagen is produced, and characteristic collagen fibers are unable to form. Wound healing is poor and capillaries fragile. Without oxygen to hydroxylate proline and lysine, a local condition resembling scurvy tends to occur.
Under normal conditions, collagen synthesis peaks by day 7, coincident with rapid increases in a tensile strength. The healing wound has the greatest mass at 3 weeks but will remodel itself over the next 6 to 12 months. Despite these impressive figures, the wound will achieve less than 15% to 20% of its ultimate strength by 3 weeks and only 60% by 4 months

50. PDS Background Indications Extended wound tensile strength required
Absorption (Hydrolysis)
In vivo tensile strength greater than Vicryl and Dexon
Day 14: 74% of tensile strength retained
Day 28: 58% of tensile strength retained
Day 45: 41% of tensile strength retained
Day 180: Complete Suture absorption
Characteristics
Less contamination of the monofilament
Stiffer and more difficult to handle
More expensive than Dexon or Vicryl