Continuing Education Activity

An umbilical hernia is a ventral hernia located at or near the umbilicus. In general, umbilical hernias tend to have a narrow neck, which increases the risk of strangulation and incarceration. The majority of umbilical hernias in adults are acquired and may occur either above or below the umbilicus.This activity explains when this condition should be considered on a differential diagnosis, articulates how to properly evaluate for this condition, and highlights the role of the inter-professional team in caring for patients with this condition.

Objectives:

• Identify the etiology of umbilical hernia.
• Review the presentation of a patient with umbilical hernia.
• Outline the treatment and management options available for umbilical hernia.
• Describe interprofessional team strategies for improving care and outcomes in patients with umbilical hernia.

Introduction

An umbilical hernia is a ventral hernia located at or near the umbilicus. The European Hernia Society classification for abdominal wall hernias defines the umbilical hernia as a hernia located from 3 cm above to 3 cm below the umbilicus[1]. It is the second most common type of hernia in an adult following inguinal hernia[2].  It accounts for 6%-14% of all abdominal wall hernias in adults[3][4].

Etiology

Umbilical hernias in adults are acquired in 90% [3].  Only 10% of adult umbilical hernia report having had hernia in childhood. It more common in women or individuals with increased intra-abdominal pressure as in pregnancy, obesity, ascites, or chronic abdominal distention. Stretching of the abdominal musculature and the presence of adipose tissue acts to separate muscle bundles and layers, weakens aponeuroses and favors the appearance of umbilical hernias [2].

Epidemiology

The Incidence of Umbilical hernia in the general adult population is 2% while it is much more common in obese multiparous women and cirrhotic patients. Up to 20% of cirrhotic patients with ascites develop umbilical hernia[5]. It is more common in females with a ratio of 3:1. In general, umbilical hernias in males most often present incarcerated, whereas females are more likely to have an asymptomatic reducible hernia. 70% of umbilical hernia repairs are carried out in male[2]. Approximately 175,000 umbilical hernia repairs are annually performed in the United States [6]. 

Pathophysiology

Anatomically, the umbilical hernia could occur either through a potential weakness present at the exit site of involuted umbilical vessels, most importantly the umbilical vein or through weakened umbilical fascia (Richet's fascia)[7].  Therefore, umbilical hernia covering consist of skin, subcutaneous tissue, weakened superficial fascia, weakened umbilical fascia and peritoneum, practically all these layers are greatly attenuated and fused together[7].  It has been noted that patients with Umbilical hernia often lack the umbilical fascia, and the round hepatic ligament is not attached to the inferior border of the umbilical ring[8]. 

Chronic abdominal wall distension with increased intra-abdominal pressure like in pregnancy, patient with ascites or peritoneal dialysis, stretching of the abdominal muscles fibers, and the weakness of connective tissue may be responsible for the occurrence of umbilical hernia[9].  About 20% of cirrhotic patients will develop umbilical hernia due to increase in the abdominal pressure from ascites, dilation of umbilical veins, and muscular or connective tissue weakness due to poor nutritional status contribute to herniation[10].

Umbilical hernia may contain preperitoneal fat tissue, omentum, and small intestine or a combination of those can take part[11]. The transverse colon is very rarely involved[12]. The neck of the hernia sac is usually narrow compared with the size of the herniated sac, hence, incarceration and strangulation are common[11]. Therefore, an elective repair after diagnosis is advised.

History and Physical

Adult with umbilical hernia typically presents with protrusion or bulging from the umbilicus[13]. Pain and GI discomfort are other possible but infrequent presenting symptoms while tenderness and incarceration are common physical finding[13].  Small-sized umbilical hernia often asymptomatic and only sometimes causes some degree of discomfort. Large umbilical hernia in older, multiparous or obese women, generally symptomatic and which usually presents with progressively enlarging hernia and in most cases becomes tender or irreducible with time [14]. Strangulation of the umbilical hernia is a frequent complication; typically patients present with irreducible tender umbilical bulge with skin color changes and signs of intestinal obstruction if the sac contains a loop of small bowel[15].

Evaluation

An umbilical hernia is diagnosed during the physical exam. Careful examination of the entire abdominal wall, especially around the previous scar is warranted. The content of the hernia and the size of the defect could be estimated. Sometimes imaging studies such as abdominal ultrasound or CT scan are warranted to evaluate for complications or if the clinical diagnosis is difficult, especially in patients with obesity[16]. It is also important to evaluate the BMI, smoking status and pre-existing Cirrhosis, given the high risk in those patient population[17].

Treatment / Management

All adult umbilical hernias need to be fixed because of the high risk of complications. surgery is indicated in symptomatic patients. Relative contraindications include uncontrolled ascites.

There are two main surgical repair options for umbilical hernias: suture repair and mesh. Primary suture repair is performed either by simple primary suture repair which can be used for small defects (<2 cm) or by using Mayo technique which is basically an overlapping abdominal wall fascia in a “vest-over-pants” manner which was described by William Mayo in 1901 [18]. Unfortunately, primary suture repair associate with 10% recurrence rate[3]. A recent randomized, double-blind, controlled multicentre trial in Europe on adults with a primary umbilical hernia of diameter 1–4 cm, and were randomly assigned (1:1) intraoperatively to either suture repair or mesh repair. There were fewer recurrences in the mesh group than in the suture group 4% vs 12%[19]. Therefore, It is recommended for umbilical hernia of >1cm to repaired by mesh.

Mesh repair can be performed via both open or laparoscopic approaches. Open mesh repair can either be placed as onlay or sublay fashion; the onlay mesh placement is the technically easier but associated with higher wound complications e.g. seroma or hematoma and surgical site infection in some cases. Preperitoneal or sublay mesh placement requires more surgical skill and experience but less recurrence and wound complications[11]. Some surgeons prefer leaving fascial margins without approximation; however, fascial closure before onlay mesh or after preperitoneal mesh is recommended [18].

Laparoscopic mesh repair can be performed either via transabdominal preperitoneal approach (TAPP) or intraperitoneal onlay mesh (IPOM) technique. Laparoscopic repair resulted in shorter hospital stay, shorter return to normal activities, lower wound complications and recurrence rates[20].

IPOM technique is based on the dissection of the sac, repair the defect with continuous suture followed by placement of mesh with a broad overlap of at least 5 cm. Abdominal wall structures like the falciform ligament must be dissected and the perivesical space must be opened to allow adequate incorporation and fixation of the mesh. [21]

TAPP approach involves reducing hernial sac contents, incising the peritoneum 5 cm away from the margin of the defect and creating a preperitoneal space. After obtaining adequate hemostasis, a mesh will be placed with at least 5-cm overlap on all sides. Finally, the mesh will be fixed with either a few absorbable tacks or suture and the same absorbable fixation system or suture will be used to close the peritoneal flap[22]. It is suggested that TAPP decrease the risk of complication related to the intraperitoneal position of the mesh and has a lower complication rate than (IPOM) procedure[22].

Differential Diagnosis

• Benign lymph node metastasis

• Epididiymo orchitis

• Epididymal cyst

• Epididymitis

• Hydrocele

• Lymphadenopathy

• Spermaotocoele

• Testicular malignancy

Prognosis

After repair, the prognosis is good. However, recurrence is common in patients who continue to gain weight. In addition, there is a small risk of bowel obstruction.

Complications

Morbid obesity, high ASA-score (≥3), onlay repair, and concomitant bowel surgery are potential risk factors for surgical complication. Lindmark et al emphasize the size of the fascial defect as an important factor in the preoperative risk evaluation of patients with a ventral hernia. They conclude that surgical complication increases by 1% for each mm increase in fascial defect size[17].  

1. Wound complications: including seroma, hematoma and surgical site infection. Open hernia repair techniques usually predispose to this kind of complication while the laparoscopic technique has resulted in a decrease in such complications[23].

2. Bowel injury and adhesion:  laparoscopic technique predisposes to this type of complications. There is a low risk for enterotomy and dense adhesion related to direct contact of the mesh with the viscera[24]. 

3. Recurrence: There is a higher recurrence rate with primary repair even in defects of <4 cm[19]. Morbid obesity > 30 kg/m, diabetes and wound infection are independent risk factors for recurrence[4]. smoking also considered a risk for recurrence[25]. Moreover, uncontrolled ascites is associated with a significant risk of recurrence[26]. 

Postoperative and Rehabilitation Care

• Nutrition: Encourage adequate hydration with approximately 8-10 glasses of water per day. It is recommended to eat a high-fiber diet to avoid constipation and excessive straining.
• Activity: Usually patients go home the same day except in complicated cases or associated co-morbidities. The majority can return to work within a few days. No lifting above 10 pounds (4.5 kg) and any strenuous exercise should be avoided for six weeks.
• Wound Care: It is important to keep the incisions clean and dry. No swimming or soaking in the bathtub for 1-2 weeks or until the staples, stitches, or steri-strips are removed.
• Pain control: NSAIDs can be used safely for a short term in the absence of renal disease or peptic ulcer disease. Acetaminophen and ibuprofen are commonly used for mild to moderate pain. Narcotic medication e.g. oxycodone, tramadol used for moderate to severe pain for a few days. It is recommended to take over the counter stool softener to avoid narcotic-induced constipation.
• Abdominal binder: applying an abdominal binder provide subjective beneficial effect and helpful at promoting postoperative recovery [27] but has no significant effects on pain, movement limitation, or seroma formation[28].

Pearls and Other Issues

• Anatomically abdominal muscles exert multiple forces that contribute to hernia formation. These forces result from contraction of the external oblique, internal oblique, and transverse abdominis muscles, as well as increased intra-abdominal pressure. The rectus abdominis muscles are the only muscle group of the anterior abdominal wall that probably does not contribute to hernia recurrence due to the contraction in cephalad-caudal direction[29].
• When the hernia defect cannot be easily approximated in the midline, component separation may be helpful. Instead a bridged mesh repair may be performed. Repair with bridged mesh associated with higher recurrence and complication rates compared with nonbridged repairs and are, therefore, suboptimal [29].
• Usually ventral hernias including umbilical hernia repaired with synthetic non-degradable meshes which are basically made from one of three main materials: polypropylene, polyethylene terephthalate polyester or expanded polytetrafluoroethylene[29]. 
• Synthetic degradable meshes are intended to reduce adhesions and provide safe repair in infected fields. Examples of this type of meshes are polyglactin and polyglycolic. The disadvantage of the mesh is that they degrade within one to three months; therefore are associated with high recurrence rates [31].
• Biological meshes used for hernia repair with infected or contaminated surgical field. It is believed to promote regeneration and new collagen deposition, rather than scarring[30]. Biological meshes are typically manufactured from human cadaver skin, porcine or bovine dermis; bovine or equine pericardium; or porcine intestinal submucosa that has been decellularized to leave a collagen matrix[31].

Enhancing Healthcare Team Outcomes

Umbilical hernias are common in clinical practice. The majority of patients are first seen by the primary care provider or the emergency department physician. Because these hernias have a high risk of incarceration, surgery is recommended in all patients. an interprofessional team approach is necessary to avoid the morbidity of an umbilical hernia. In patients with associated comorbidity, a preoperative workup is necessary to reduce post-surgery complications. The nurse anesthetist must make sure that the patient is fit for surgery. Patients with cirrhosis and or ascites need to be thoroughly assessed prior to surgery, as complications are common

Once the surgery completed, the nurse should educate the patient on the importance of losing weight, quiet smoking and avoiding heavy lifting. Patient must be educated on healthy diet. Once the healing completed, the patient should be encouraged to increase physical activities and lose weight. This is vital in preventing a recurrence.

Nurse practitioners who see children should educate the parent that small hernias will spontaneously close but if they still remain open by age 5, surgery is required.

Most patients with an umbilical hernia have a good outcome, but despite advances in treatment with a mesh, recurrences do occur in about 1-3% of cases.[32][33]