**3.2. Infection (wound, UTI, pneumonia)**

then, the improvements in surgical approach emphasized intended to reduce the long-term hernia recurrence and complications. The use of synthetic material for support was introduced in the early 1900s by Handly by using silk for prosthetic support, but soon after it was found to increase the incidence of wound infection [1]. Risk factors for hernia include, but are not limited to, previous operations, physical stress, constipation, smoking, aging, trauma, family history, systemic disease, and obesity. Hernia repair is among the most common surgeries performed worldwide today, in which more than 75% found to be in the groin region, mainly inguinal canal hernias [2, 3]. The overall risk of developing hernia in a lifespan is around 15% in males and 5% in females, with proportionate increase in risk as the age increases. Inguinal hernias affect around 3–4% of the general population worldwide [4]. Differential diagnoses encompass any pathology that could lead to pain or mass formation in the groin area in particular. Such diagnoses include, but not limited to, soft tissue, lymphoid tissue, associated vessels, bony structures, and reproductive organs [5, 6]. Even though hernias, in general, are associated with overall promising short and long-term outcomes, there are still some complications to be recognized [7].

Incarceration is the process by which hernia contents are trapped within a hernial sac in which reducing them is not possible. This result in decreased venous and lymphatic flow thus edema of incarcerated tissue. As a result, normal gut flora start flourishing and gas accumulates due to bacterial fermentation. As the swelling enlarges, the arterial blood flow to the hernial sac contents is compromised leading to ischemia and tissue necrosis, which is known as hernia strangulation [8]. These two entities are complications of hernia itself and are associated with increased rates of mortality and morbidity. The risk of incarceration and subsequent strangulation tend to be higher in the first few months to years and decrease with time. Gallegos et al. [9] estimated the probability of incarceration to be around 2.8% at 3 months and 4.8% at 2 years, which might be partially due to weakening of the abdominal wall and decreased pressure on the sac and its contents [9, 10]. Some of the risk factors for incarceration and subsequent strangulation include advanced age at the time of presentation, femoral hernia, and recurrent hernia [8]. Morbidity and mortality are determined by many factors including the patient age, comorbidities, and duration of the strangulation, the longer the duration, the greater the strangulation risk. For the reasons mentioned above along with an increased risk of perforation, a strangulated hernia is considered a surgical emergency that mandates surgical intervention with possible bowel resection. If the strangulation lasts longer than 4–6 hours on average bowel resection may be warranted. In such scenarios, placement of prosthetic mesh is usually not advised, as there will be a higher chance of bacterial translocation and wound infection [11, 12].

The incidence of complications associated with laparoscopic surgery is low on average when compared with an open approach. Most of the serious complications occur during access

**2. Complications of an untreated hernia**

**2.1. Incarceration and strangulation**

94 Hernia Surgery and Recent Developments

**3. Complications of hernia surgery**

**3.1. Surgical complications**

Despite the fact that in the modern era advanced aseptic measures have decreased the incidence of post-operative infection; it is still a leading cause and a well-known complication of hernia surgery. Infections could be from multiple sources including the suture used and/ or mesh. It is reported that infection incidences are as low as 1%, or even less, in multidisciplinary specialized hernia practice [17]. The most common underlying organisms are grampositive skin flora. It was found that there is a slightly increased risk of infection with groin herniorrhaphy. Usually, it is hard to determine the extent of infection, whether skin and soft tissue are only involved, or deeper infection involving the mesh is there. Either way, should be treated with aggressive antibiotics and drainage, especially in the setting of a foreign body such as mesh [18].

From a broader perspective, surgical site infections are seen in around 1% of clean wounds and around 35% of contaminated wounds. **Table 1** lists different types of surgical wound infections. Clinical features include erythema, induration, warmth, and frothy discharge later in the course [19, 20]. The incidence of surgical wound infections can be reduced by following simple measures. For example, avoiding surgery in the setting of an active infection, antibiotic prophylaxis, proper skin preparation, maintaining sterile conditions throughout the surgery, and proper wound dressing [21].

#### **3.3. Fascial dehiscence**

Dehiscence is usually due to abdominal wall tension that exceeds the tissue and suture strength. It can be seen early in the post-operative period, and it could also happen as a late complication that might involve the full length of the surgical suture or part of it. Its incidence is estimated to be around 1–3% depending on the type of abdominal surgery. Despite of the improvement in the surgical techniques and wound management, the overall risk of fascial dehiscence remains unchanged [23–25].

Risk factors for wound dehiscence can be sub-classified into patient risk factors and those related to surgical site and surgeons' techniques. Patient risk factors include age, male gender, ascites, chronic pulmonary disease, post-operative cough, obesity, malnutrition, and chronic glucocorticoid therapy [19, 26]. Surgical technique risk factors include the length of the surgical wound if bigger than 18 cm or not. Suture failure is a major cause of fascial dehiscence, and it is said that in around 95% of cases knots are intact, but they have been pulled through the fascia resulting in fascial edge necrosis [27, 28].


growth and infection. Overall hematomas are far more common than seromas and both could be prevented with a careful hemostasis during surgery [31]. One of the primary causes of hernia recurrence is wound tension; excessive tension could lead to tissues pulling apart thus recurrence at an early stage post-operatively. Excessive tension can also lead to tissue ischemia leading to sutures pulling apart or even falling off. Henceforth new modalities of tension free and suture-free hernia repairs are being promoted by experts such as

Worst Case Scenarios! Complications Related to Hernial Disease

http://dx.doi.org/10.5772/intechopen.76079

97

Another factor to consider is the size of the initial hernia defect which is proposed proportional to the risk of developing recurrence in the aftermath of hernia repair. This fact might be explained by the quality of the tissue and fascia surrounding the defect area. As the defect grows bigger it affects the surrounding fascial plans making them weaker and relatively more ischemic in comparison to smaller sized defects. Isik et al. [33] found that higher levels of matrix metalloproteinase s-1-2-9-13, in addition to decreased levels of tissue inhibitors of metalloproteinases-1-2-3 played an integral role in the formation of inguinal hernia, leading to dysfunction of collagen fibers, which will result in weakening of fascia, indicating that a hernia is not only a local issue, but rather a reflection of systemic disease [33]. Other etiologies for hernia recurrence include complicated hernia at presentation such as incarceration or strangulation, in which the tissue will be inflamed and edematous providing a good medium for recurrence as the tissue is unhealthy, to begin with. Another causative agent for recurrence is smoking which is said to increase proteolytic enzymes and decrease protective factors

Nerve injury could be a terrible consequence of an otherwise successful surgery presenting with pain, loss of sensation or muscular weakness. Neuralgia, commonly known as postoperative pain, is a rather common complication with varying degrees of pain after herniorrhaphy and follows nerve distribution. While some degree of post-operative pain is expected after surgery, for the diagnosis of post-herniorrhaphy neuralgia to be made, pain should persist for more than 3 months, not to be attributed to any other cause and interfere with patient social and/or sexual life [34, 35]. The differential diagnosis for post-herniorrhaphy neuralgia includes hernia recurrence, mesh infection or displacement, osteitis pubis, and fluid collection. Open approach injuries usually affects the ilioinguinal nerve, iliohypogastric nerve, genital branch of the genitofemoral nerve, while injuries to the lateral femorocutaneous nerve is more common with laparoscopic approach, see **Table 2** [1, 36].Most of the time, the mechanism of injury is attributed to nerve entrapment within the mesh or the suture line. This can be prevented with careful handling of the tissue and preventing over manipulation of the nerves. In laparoscopic approach staple placement below the iliopubic tract decreases the risk

Ilioinguinal and iliohypogastric nerves are mostly injured during elevation of the external oblique fascia. The genitofemoral nerve is thought to be injured following cord isolation for cremasteric muscle fibers stripping. As soon as the nerves are identified, they are retracted out of the field by encircling them with a vessel loop and retraction. While injury happens with

Lichtenstein [7, 32].

involved in tissue healing [11].

of nerve entrapment [37].

**4.2. Neuralgia**

**Table 1.** Types and criteria for the diagnosis of surgical wound infection [22].
