Management of Strangulated Inguinal Hernia

Abstract

Strangulated inguinal hernia occurs when part of the hernia becomes irreducible and subsequently causes bowel ischemia secondary to a reduction in blood flow to the hernia. Therefore, management strategy differs and depends on the presentation of the hernia, duration, patient, and surgical factors. One thing is for sure: conservative management is not recommended for a strangulated inguinal hernia, as it always requires surgical intervention. Among others are diagnostic laparoscopy, open hernioplasty with the hybrid technique, and laparotomy followed by inguinal herniorrhaphy. Eventually, the outcome of the surgery has to be considered while managing strangulated inguinal hernia cases. Prompt diagnosis and management are required to reduce the morbidity and mortality associated with strangulated inguinal hernias.

1. Introduction

Hernia is defined as a protrusion of the viscus or part of the viscus through an abnormal opening of the walls of its containing cavity. The incidence in full-term babies is estimated at 1–5%, and it is close to 10% in pre-term babies (bilateral hernias are more common in pre-term babies). The most commonly protruded viscus includes the small bowel, large bowel, omentum, bladder, appendix (amyand’s hernia), or even gynecological organs.

An inguinal hernia happens due to the weakening of the lower abdominal wall for various reasons. Congenitally, it is due to patent processes vaginalis which is an outpouching of the peritoneum [1]. It affects both men and women of various ages. However, inguinal hernia is more prevalent in males, whereas femoral hernia is more common in females. Having said that, strangulation is seen more in the femoral hernia as opposed to the inguinal hernia due to the narrow neck of the femoral hernia. Generally, the femoral hernia will pass inferior-laterally to the pubic tubercle whereas the inguinal hernia, on the other hand, will pass superior-medially. Direct inguinal hernia involves protrusion of the viscus through the weakening of Hesslebach’s triangle. The inguinal ligament, inferior epigastric vessels, and the lateral edge of the rectus sheath all encircle these triangles.

Inguinal hernias can be managed conservatively unless the patient presents with obstruction or strangulation, where surgical correction is warranted [1]. Reducible inguinal hernias can be managed expectantly with an outpatient elective hernioplasty. Irreducible hernias, on the other hand, need further assessment and intervention. Based on a Cochrane review, it can be concluded that eventually, 54% of all inguinal hernias need surgical intervention due to complications such as incarceration or strangulation. Hence, elective surgical intervention is usually suggested for all patients with inguinal hernias. The attending surgeon should explain clearly to patients the various available options and possible complications should the patient present in an acute setting with intestinal obstruction. This is because the morbidity and mortality of hernioplasty increase in the emergency setting as opposed to the elective setting. A holistic approach needs to be taken when managing such complicated cases. Proper communication and documentation should be done in dealing with such cases to avoid any potential medico-legal issues later.

Patients with a strangulated inguinal hernia usually present with nausea and vomiting, localized abdominal pain, abdominal distention, absolute constipation or diarrhea, per-rectal bleeding in cases of bowel ischaemia and less commonly, fever. Clinically, these patients will be in pain, dehydrated and septic looking. Prompt resuscitation is needed to reverse the physiology back to normal before the operation. Chest and abdominal radiographs can be taken to look for any evidence of bowel strangulation or perforation. Fluid resuscitation, analgesia, and antibiotics should be commenced as soon as possible upon presentation in cases suspecting bowel ischaemia. Following adequate resuscitation, the patient should be brought to the operating theater for definitive surgery.

A prospective study done by Nazir Ahmad et al. found that the common operative procedure for strangulated hernia includes Darning and Bassini repair, resection and primary anastomosis of the ileum, partial omentectomy, obliteration of inguinal canal and lastly orchidectomy [2]. The treatment strategy is usually individualized depending on the patient’s presentation to the emergency department. If bowels are viable, a mesh repair is recommended. However, if there is bowel ischaemia needing bowel resection, the best would be to proceed with darning or Bassini repair.

It has always been a debate about whether to apply mesh in cases where bowel resection is done. The risk of mesh infection requiring explanation as opposed to the risk of hernia recurrence later should be taken into consideration. We have to bear in mind that mesh infection can lead to severe intrabdominal sepsis and even death has been reported in some cases. Therefore, the operating surgeon must pay attention to all these potential issues when managing strangulated hernia cases.

2. Discussions on management of strangulated hernia

Irreducible inguinal hernia can either result in incarceration or strangulation. An incarcerated inguinal hernia is a hernia in which the content has become irreducible due to a narrow opening in the abdominal wall or due to adhesions between the hernia content and the sac. Intestinal obstruction may further complicate an incarcerated hernia. Usually, an incarcerated hernia can be managed electively as opposed to strangulated hernia.

A strangulated hernia on the other hand occurs when the blood supply to the contents of the hernia is compromised. This is a surgical emergency and warrants urgent surgical attention and intervention. Patients usually present with intestinal obstruction which can lead to subsequent necrosis, ischaemia and bowel perforation of the involved bowel within the hernia sac. Clinical presentations of strangulated hernia include erythema, oedema and severe pain.

Irreducible hernia can also result in testicular damage or even atrophy secondary to pressure effects in boys [1]. Taxis or manual reduction of irreducible inguinal hernia should be avoided at all times. The reason is that what if the content reduced is part of the ischemic bowel stuck within the deep ring? The strangulation of the bowel can lead to the release of many toxins formation secondary to the injured mucosal wall. This will eventually lead to intraabdominal sepsis with significant morbidity and mortality. Therefore meticulous assessment in decision-making is warranted in dealing with such cases.

Decision-making in managing such cases should not be taken lightly as the material risk associated is high. Any delay in surgical decision-making can result in serious post-operative morbidity or even mortality [3]. Figure 1 shows summarizes the diagnosis of strangulated hernia.

Figure 1.

Diagnosis of strangulated inguinal hernia.

The commonly encountered problems include whether the strangulated portion of the bowel is viable and can be returned to the abdomen or whether resection has to be carried out. When the bowel is deep purple color and the sac contains a hemo-serous dark fluid, the likelihood of bowel ischemia needing bowel resection is extremely high.

There are a few ways to check for normal bowel viability which include a shining peritoneal surface, deep red in color with active peristaltic movement suggestive of normal bowel viability [3]. In short, timing is of utmost essential in the management of strangulated hernia as any delay in diagnosis and subsequent delay in operative intervention can result in high morbidity and mortality. Early diagnosis of strangulated hernia can be difficult, however, missed or late intervention can result in deadly septic complications.

Figure 2 shows the description of various methods for managing strangulated inguinal hernias. No one method is superior to the other, every surgical intervention has its pros and cons. Hence, it is imperative to note that treatment strategies should be tailored accordingly. Ultimately, the outcome of the surgery is what matters. They are many ways in dealing with strangulated hernia, based on the above-mentioned figures, it can be broadly divided into open and laparoscopic surgery. However, it has to be taken into consideration that laparoscopic hernia repair, especially in acute presentation with strangulation can be technically challenging. Open hernia repair closes the defects anteriorly and laparoscopic hernia repair (TAPP - transabdominal pre-peritoneal/TEP - totally extraperitoneal) closes the defects posteriorly. If the first surgery is done via open surgery, should the patient present with recurrence, a posterior approach should be advocated laparoscopically. However, if patients present under emergency as strangulated hernia, open surgery should be advocated. The role of laparoscopic hernia repair in emergency settings is debatable, depending on the availability of resources and local expertise [4].

Figure 2.

Management of Strangulated Hernia.

Moving on, the following are the various available options for managing strangulated inguinal hernia. Firstly, open hernioplasty or herniorrhaphy with hernioscopy. This subset of patients includes those that can be reduced spontaneously on admission but complain of persistent pain post taxis. For this group of patients, emergency inguinal exploration can be done.

Hernioscopy is done to enable the surgeon to visualize the entire peritoneal cavity, particularly looking into any evidence of bowel ischaemia needing bowel resection and anastomosis. This technique can be challenging and requires a steep learning curve. From the hernia sac, a trocar containing a laparoscope is inserted and held in place using a stay suture, pneumoperitoneum is created, and the abdominal cavity is inspected for any evidence of bowel ischemia. If negative, the best option would be Lichtenstein mesh hernioplasty. In situations where the bowels are compromised, the feasibility of the incision should be decided by the surgeon. In cases where the bowel is dilated needing decompression and resection, midline laparotomy should be performed, and the inguinal defect closed via fascial repair.

Frequently performed techniques for fascial repair include Darning repair and Shouldice repair. In darning repair, a continuous suture is done between the conjoint tendon and the inguinal ligament without approximating the two structures. On the other hand, in Shouldice repair, a four-layered reconstruction of the posterior inguinal region is performed, approximating conjoint tendon to transversalis fascia, transversalis fascia to the inguinal ligament and internal oblique to the inguinal ligament.

The risk of inguinal hernia recurrence following fascial repair is high. However, what remains a debate, is Lichtenstein mesh hernioplasty following bowel resection from a strangulated inguinal hernia is recommended. The risk of mesh explanation and subsequent prolonged hospital stay for sepsis secondary to mesh infection is very high. It can even result in mortality. This is assuming there is an infection of the mesh, however, if there is no risk of mesh infection, Lichtenstein mesh hernioplasty is the widely accepted surgical procedure for inguinal hernia.

Moving on to the next treatment option is laparotomy and herniorrhaphy with or without bowel resection. This subset of patients includes those with radiological, biochemical and clinical evidence of bowel ischemia. Generally, patients would have dilated bowels and distended abdomen. By performing midline laparotomy, the surgeon can easily perform bowel decompression proximally, distally or via enterotomy.

At the same time, a midline laparotomy allows closer inspection of the bowel to look for any evidence of bowel ischaemia. Proper surgical exposure facilitates surgery and improves the outcome of surgery while reducing the operating time. The inguinal defects can be closed while doing the laparotomy. However, the risk of recurrence is always there since only fascial repair is done and the patient should be well informed.

On the other hand, if no bowel resection is done, following midline laparotomy, a Lichtenstein mesh hernioplasty is strongly recommended. Another inguinal incision is usually performed once the midline laparotomy wound is closed, and Lichtenstein mesh hernioplasty is performed.

Bapurapu Raja Ram et al. published a new method called the “Window to window – one skin incision” approach. In this method, there is no division of the muscle and inguinal nerve and no ligation of the inferior epigastric artery, hence the normal anatomy is retained. Bowel resection and anastomosis are done through the same incision away from the site of the mesh repair that can be covered with a mop during operation. The incision that is used by the author is not the conventional inguinal skin crease approach, but the window-to-window – one skin incision. However, the limitation of this study is one centre and one team. Hence, it requires further multicentre study and analysis [5].

Figure 3 shows a pre-operative and intra-operative picture of a patient that presented with 3 days history of pain, progressively worsening upon presentation. Blood results revealed high lactate, leucocytosis and metabolic acidosis in blood gas. Following resuscitation, the patient was counseled for surgery and consented. Intra-operatively, noted a small bowel loop stuck at the deep inguinal ring, the bowel appeared blue and dusky with hemo-serous fluid within the hernia sac. In this case, an inguinal incision is made initially to assess for bowel viability, followed by a midline laparotomy. The Shouldice fascial repair was done for this patient.

Figure 3.

Midline laparotomy, inguinal herniorrhaphy, bowel resection and primary anastomosis for strangulated inguinal hernia.

The next treatment approach is the minimally invasive surgical (MIS) approach in managing strangulated inguinal hernia. If expertise is available, a strangulated inguinal hernia repair can be attempted laparoscopically. Laparoscopic transabdominal pre-peritoneal (TAPP) repair can be done if there is no bowel ischaemia needing bowel resection. In cases where bowel resection is needed, it can also be done laparoscopically, however, this procedure is technically challenging. Usually, these procedures are performed in high-volume hernia centres [4].

Proper patient selection is required to prevent complications later. This is because, although minimally invasive technique is advocated, we have to bear in mind that it’s not without complications. However, the application of mesh especially in cases where bowel resection and anastomosis were done should be avoided as the risk of mesh infection is high in this group of patients, even though a minimally invasive technique is advocated [6].

Last but not least, a hybrid technique can be undertaken while managing strangulated inguinal hernia cases. The hernia can be reduced laparoscopically followed by Lichtenstein mesh hernioplasty in cases where there is no bowel ischaemia. If there is evidence of bowel ischaemia, following laparoscopic reduction of hernia content, bowel resection should be done, either open or laparoscopically. The principle is still the same in managing strangulated inguinal hernia. In cases where bowel resection is performed, mesh hernioplasty is not recommended. Instead, the fascial repair is preferred to prevent peritoneal protrusion through the myo-pectineal orifice.

Besides this, other pertinent issues need to be addressed when managing strangulated inguinal hernia. Among others includes, managing the co-morbidity of the patients which includes diabetes mellitus and hypertension, nutrition status, sepsis due to bowel ischemia and lastly the pain secondary to strangulated hernia itself. All these need to be addressed and patients need to be optimized medically before embarking on surgical intervention. Detailed consent-taking is indicated in managing complicated hernia cases. A detailed explanation of the complications needs to be informed to patients to avoid any potential medico-legal problems. An ideal consent for strangulated inguinal hernia cases should include open hernioplasty, keeping in view bowel resection, stoma, midline laparotomy and orchidectomy.

Next, the question about hernia repair with or without mesh or even the use of biological mesh is controversial and debatable in emergency strangulation cases. Based on a few randomized control trials (RCTs), the usage of biological mesh for hernia repair involving large defects or recurrent hernias, especially in morbidly obese patients, is preferred [7]. There are several biological grafts available in the current market. Generally, if bowel resection is performed, herniorrhaphy is preferred rather than mesh repair as the risk of surgical site infection is high in dirty wounds, given the high recurrence rate which can be dealt with later in a more controlled environment as opposed to mesh repair that may or may not get infected. Hence, all these factors should be considered while managing strangulated inguinal hernia.

Another issue that needs to be highlighted is the occurrence of abdominal compartment syndrome following hernia repair. This subsets of patients include those with strangulated hernia with loss of domain. Assuming the hernia content can be reduced completely, the intra-abdominal pressure can be raised giving rise to abdominal compartment syndrome. If a patient presents to your clinic, then there are many ways to increase abdominal wall compliance while waiting for an elective surgery date. Among others include progressive pneumoperitoneum every week up to a few sessions and botulinum toxin injection on the anterior abdominal wall pre-operatively. Intra-operatively, to reduce the incidence of abdominal compartments, the content of the hernia can be resected to reduce the intraabdominal pressure. Post-operatively, patients at risk of abdominal compartments should be nursed in the intensive care unit and abdominal pressure can be measured constantly.

3. Conclusion

In summary, the management of strangulated inguinal hernia requires a multidisciplinary approach. Prompt diagnosis, adequate resuscitation and appropriate surgery need to be instituted soonest. Complications of bowel strangulation with regards to delayed diagnosis, misdiagnosis and delayed presentation lead to significant morbidity and even mortality. Treatment strategy should be tailored according to the patient’s presentation and the best available surgical expertise.

Acknowledgments

Special thanks to Dr. Dayang Corieza Febriany, Clinical Radiologist and Medical Lecturer from the Department of Radiology, Faculty of Medicine and Health Sciences, University Malaysia Sabah for your input in radiological imaging.

Conflict of interest

No conflict of interest.

Notes

I would like to express my gratitude to my parents, wife and lecturers for their continuous support during the writing of this chapter in the hernia book.