Nissen Fundoplication

Anatomy and Physiology

To understand anti-reflux surgery, clinicians must have a firm grasp of the foregut anatomy, particularly the lower esophageal sphincter and stomach.

The lower esophageal sphincter consists of four anatomic structures:

1. The intrinsic musculature of the distal esophagus, which is usually in a state of tonic contraction.
2. The sling fibers of the gastric cardia, which contribute to the high-pressure zone of the lower esophageal sphincter.
3. The crura of the diaphragm, which surrounds the esophagus at the esophageal diaphragmatic hiatus.
4. The gastroesophageal junction, which should be located intra-abdominally so that the intra-abdominal pressure on the distal esophagus prevents reflux.

The stomach begins at the diaphragmatic hiatus, or lower esophageal sphincter, and ends as it continues as the first portion of the duodenum. It is divided into the cardia, fundus, body, antrum, and pylorus. The cardia is just distal to the gastroesophageal junction, the fundus abuts the left diaphragm, and the pylorus is the most distal portion entering the duodenum. The lesser curvature lies beneath the medial segments of the liver and contains the incisura angularis. The incisura angularis can be identified as the junction of the vertical and horizontal parts of the lesser curvature, which marks the transition of the body to the antrum. The greater curvature is the long left lateral border of the stomach. It runs from the fundus to the pylorus, which is connected to the greater omentum. The left border of the intraabdominal esophagus and the fundus meet at an acute angle called the angle of His.

Ligaments

• Gastrohepatic ligament: lesser curvature to the medial liver edge, contains the left and right gastric arteries. This may contain a replaced left hepatic artery.
• Gastrophrenic ligament: fundus to left hemidiaphragm, avascular.
• Gastrosplenic ligament: greater curvature to the spleen, which lies in the left upper quadrant. It contains the short gastric vessels.
• Gastrocolic ligament: inferior stomach to the transverse colon, considered part of the greater omentum. It contains the gastroepiploic vessels.

Indications

For a patient to be a candidate for anti-reflux surgery, preoperative testing should be done. These tests include: 

1. Esophagogastroduodenoscopy (mandatory): used for the assessment of esophagitis as well as the gastroesophageal junction flap.
2. Ambulatory pH monitoring: considered ideal for the diagnosis of gastroesophageal reflux disease. This test must be done to confirm the diagnosis unless a prior esophagogastroduodenoscopy has shown peptic strictures of Los Angeles class C or D esophagitis which is pathognomonic for gastroesophageal reflux disease.
3. Barium esophagram: useful for preoperative evaluation of the gastroesophageal junction anatomy, including the presence of a hiatal hernia and the length of the intra-abdominal esophagus. 
4. Esophageal manometry: used to detect esophageal motility disorders and can influence the use of a partial or complete wrap. It also measures the lower esophageal sphincter resting pressure.

The indications for LARS are relative. It is generally considered for patients who have severe symptoms attributed to gastroesophageal reflux disease along with one of the following:

• Repeated aspiration pneumonia or asthma related to reflux
• Barrett esophagus (controversial)
• Failed maximal medical therapy
• Unable to take medications due to compliance or side effects
• Younger patients who do not want to take chronic medications in the interest of adverse effects and long-term cost[3]

Anti-reflux surgery may be open or laparoscopic. There is clear evidence for the benefits of laparoscopic ARS regarding morbidity and hospital length of stay. Many different LARS techniques are available. They include Dor fundoplication, an anterior 180-degree wrap; Toupe fundoplication, a posterior 270-degree wrap; and Nissen fundoplication, a total posterior 360-degree wrap.[4]

Choosing the surgical technique is up to clinician preference. A plethora of data is available comparing the partial to the total wrap. The literature reveals mixed results, but the consensus supports fewer postoperative complications and comparable symptom relief. However, there is a higher chance of recurrent symptoms when comparing partial fundoplication and total fundoplication. Less favorable outcomes have been more consistently shown for an anterior partial wrap and are considered a less durable form of repair. These differences seem to be less clinically significant in long-term data for complete and posterior partial wraps. There is no standard LARS and the most common ARS performed in the United States is the Nissen fundoplication.[5][6][7][8][9]

Contraindications

Absolute contraindications for LARS are common to all laparoscopic surgeries. They include the patient's inability to tolerate general anesthesia and uncorrectable coagulopathy.

Relative contraindications include previous upper abdominal surgery, severe morbid obesity with a body mass index greater than 35, and esophageal motility disorders. Patients with a body index over 35 may benefit from gastric bypass surgery.

Equipment

The basic laparoscopic equipment required for this operation includes insufflation with CO2, drapes, monitors, laparoscopic instruments, and electrocautery.

Additional equipment specific to the procedure includes:

• Four trocars ranging from 5 mm to 10 mm 
• A liver retractor
• 30-degree angled laparoscope
• Size 52 to 60 French bougie
• Endoscope
• Laparoscopic ultrasonic energy device dissector

Personnel

For the preoperative evaluation, unless the surgeon is comfortable with endoscopy, a gastroenterologist may need to be involved.

The operative portion of the surgery requires an anesthesiologist, a primary surgeon, a scrub nurse, and a first assistant.

Preparation

The patient will be given preoperative antibiotics 30 minutes before incision, as well as venous thromboembolism prophylaxis. The hair on the patient's abdomen is removed with clippers in the preoperative area. The patient is then placed on the operating table and secured correctly. After induction of anesthesia, an orogastric tube is positioned within the stomach. The patient is placed in the lithotomy position with their arms extended. Routine skin preparation is performed from the nipples to the pubic symphysis. A time-out is performed.

Technique or Treatment

There are many ways to perform a laparoscopic Nissen fundoplication. An example is provided below and detailed in a step-wise fashion.

1. Insufflation and trocar placementInsufflation is achieved with the Veress needle technique and direct entrance to the peritoneal cavity. A camera port is placed near the umbilicus. The remaining ports are placed under direct visualization as follows: 5 mm right subcostal anterior axillary line, 10 mm left subcostal anterior axillary line, and a 5 mm left subcostal mid axillary line. A liver retractor is placed in the subxiphoid position. The patient is then placed in a steep reverse Trendelenburg position. The primary surgeon will utilize the right and left anterior axillary line subcostal ports. The assistant will use the umbilical camera port as well as the far left subcostal port.
2. Left crural dissection and division of the short gastric vesselsExposure of the phrenogastric ligament is facilitated by traction of the gastroesophageal junction fat pad. The phrenogastric ligament is then divided. The surgeon's left-handed instrument grasps the greater curvature and traction is placed on the stomach anteriorly to expose the short gastric vessels. The assistant grasps the lateral gastrosplenic ligament and provides left lateral traction. An ultrasonic dissector is used to sequentially divide the short gastric vessels approximately 1 cm lateral to the stomach wall. This action is completed superiorly to the angle of His, which will facilitate complete visualization of the left crus.
3. Right crural dissectionThe gastrohepatic ligament is opened beginning at the pars flaccida. It is divided superiorly, taking care to avoid injury to the vagal branches as well as any aberrant left hepatic artery if present. The right phrenoesophageal membrane is then incised to expose the right crural fibers underneath it. A retroesophageal window is made while taking care to avoid the left and right vagus nerves that run on the anterior and posterior walls of the esophagus at the gastroesophageal junction. A Penrose drain is placed around the esophagus at the level of the hiatus and used to facilitate caudal retraction.
4. Esophageal mobilizationThe distal esophagus is first mobilized in the posterior mediastinum and then anteriorly/posteriorly in the intra-abdominal cavity. Take care to avoid injury to the vagus nerves and the pleura. This must be done until a minimum of 3 cm of esophagus lies in the abdominal cavity without traction. Particularly in cases of a large hiatal hernia or a para-esophageal hernia, there can be adhesions from the posterior mediastinum to the esophagus. These can result in the shortening of the intra-abdominal esophagus. The first step to correct this is to perform extensive mobilization of the esophagus up to the level of the inferior pulmonary veins. If a short esophagus persists despite maximal mediastinal mobilization, one can gain more length with the transection of the vagal trunks. Typically, a unilateral vagotomy yields 1 to 2 cm of additional length, and bilateral vagotomies will yield 3 to 4 cm of additional length. There are theoretical disadvantages of vagotomy in fundoplication patients. However, a study of 102 patients receiving a vagotomy versus no vagotomy revealed little difference concerning postoperative pain, bloating, diarrhea, and early satiety.[10] If the previous techniques have not yielded adequate length, a stapled-wedge Collis gastroplasty may be performed. It will create a neo-intra-abdominal esophagus.
5. Crural approximationThe right and left crura are reapproximated posteriorly, utilizing 2 to 3 heavy (0) permanent sutures.
6. Preparation for wrap creationThe orogastric tube should be replaced with a 52 to 60 French bougie. A marking stitch is placed in the posterior fundus. This stitch is done by grasping the greater curvature of the stomach and reflecting it to the patient’s right side, exposing the posterior fundus. The suture should be placed 3 cm distal to the gastroesophageal junction and 2 cm from the grasped greater curvature.
7. Creation of the wrapThe posterior fundus is passed behind the esophagus from left to right. The anterior fundus is grasped 2 cm from the greater curvature and 3 cm distal to the gastroesophageal junction. It is then brought in front of the esophagus to join the posterior fundus at the 10 o'clock position on the anterior aspect of the esophagus. The fundus must be grasped anteriorly and posteriorly at a position equidistant from the greater curvature to avoid incorporation of the gastric body into the wrap. Three to 4 seromuscular sutures are placed from left to right in 3 structures. First is the anterior fundus, second is a seromuscular bite of the esophagus, and lastly is the posterior fundus. The first stitch is the most cephalad placed suture; the formerly-placed marking stitch determines its location. The remaining sutures are placed sequentially to cover a total of 3 cm of the intra-abdominal esophagus.
8. Anchoring the wrapThe bougie is removed. The wrap is secured to the diaphragm in three places: the right lateral, left lateral, and posterior positions. Securing the wrap prevents herniation into the posterior mediastinum. It also prevents distal wrap migration around the gastric cardia.
9. ClosureA fascial closure is done at the 10-mm port sites. Skin closure is done at all sites.
10. Postoperative carePatients are admitted to the general surgical ward and given a clear liquid diet on the day of surgery. The diet is advanced to full liquids on postoperative day 1. As long as the patient is tolerating a diet and can maintain hydration, they can be discharged. The patient will slowly introduce soft foods into their diet, and will usually resume a regular diet at 4 to 6 weeks postoperatively.

Complications

Intraoperative Complications

Pneumothorax is a rare complication of LARS with an incidence of less than 2%. Typically, it is a consequence of pleural violation without injury to the lung. Carbon dioxide will diffuse into the pleural cavity but will be rapidly absorbed and is rarely of clinical consequence. If a pleural violation is identified intraoperatively, the opening should be repaired with suture. If a postoperative chest X-ray shows a pneumothorax, it may be managed conservatively with oxygen therapy. Serial chest X-rays are minimally useful. They are only indicated in patients who continue to require oxygen therapy or are symptomatic from the pneumothorax, as in shortness of breath. Rarely, this is a cause of tension pneumothorax requiring chest tube drainage.[11]

Gastric or esophageal perforation is another complication of LARS. Its incidence is less than 1%. If identified intraoperatively, it should be repaired with sutures. Postoperative diagnosis typically requires reoperation unless the leak is small or contained and the patient is hemodynamically stable.[12][13]

A splenic injury may occur during the mobilization of the fundus intraoperatively. This injury is usually parenchymal and may require splenectomy. A more rare complication is a postoperative splenic infarction due to inadvertent coagulation of branches from the main splenic artery. This injury occurs during the division of the short gastric arteries.

Postoperative Complications

A feeling of gastric distention, nausea, and even inability to intake liquids following LARS can occur. These effects are thought to be multifactorial. They involve a mechanical barrier at the gastroesophageal junction that prevents belching as well as vagal nerve fiber injury leading to relative gastroparesis. This is a common postoperative effect, but it persists in few patients. If an individual has persistent nausea with inadequate oral intake, an abdominal X-ray should be obtained. If there is evidence of gastric distention, a nasogastric tube should be placed to decompress the stomach temporarily. Very rarely do patients require further interventions.[14]

A temporary mild postoperative dysphagia is expective after LARS. It is secondary to the expected postoperative edema at the fundoplication site. A more rare etiology is a hematoma at the wrap site which usually causes more severe dysphagia. However, it is also self-limited. Mild dysphagia is normal during the first 2 to 4 weeks postoperatively. If the patient can tolerate liquids in early postoperative care with mild subjective dysphagia, they should be watched without intervention. If the patient cannot tolerate fluids to keep themselves hydrated, an upper gastrointestinal series should be obtained. This series will rule out anatomical abnormalities such as a postoperative hiatal hernia. If the patient has subjective dysphagia for greater than 3 months postoperatively, an upper gastrointestinal series should also be obtained. At this time if the upper gastrointestinal is normal, an esophagogastroduodenoscopy with balloon dilation of the gastroesophageal junction should be performed.[15]

Less than 10% of patients have recurrent symptoms after LARS.[16] All patients with recurrent or persistent symptoms should be evaluated with ambulatory pH studies and manometry. If there is evidence of distal esophageal acid exposure, then an upper gastrointestinal esophagram and an esophagogastroduodenoscopy should be performed. If a diagnosis of recurrent gastroesophageal reflux disease without anatomical reasons is made, treatment with proton pump inhibitors should be initiated. If there is no alleviation of symptoms, reoperation is warranted.[17]

A slipped wrap is secondary to technical errors during surgery. Preventative measures include tacking sutures to the diaphragm and complete mobilization of the fundus and esophagus, with at least 2 to 3 cm of the intra-abdominal esophagus. These measures help avoid wrapping the fundus onto the stomach as opposed to the fundus onto the esophagus. The Nissen fundoplication can slip caudally in the postoperative period. This slip may occur immediately postoperatively or gradually. Caudal slippage leads to the acid-producing stomach being incorporated in the wrap, thus leading to increased reflux and severe esophagitis, gastritis, or ulcer formation. Diagnosis is made with barium upper gastrointestinal series and esophagogastroduodenoscopy. The required treatment is reoperative; the surgeon must redo the fundoplication.

Clinical Significance

With the advent of laparoscopy, anti-reflux procedures are becoming a more commonly accepted method for the treatment of gastroesophageal reflux disease. There are three main types of LARS, and the two most commonly performed are the complete and partial posterior wraps. The anterior wrap has been shown to be inferior to the other two techniques when considering symptom relief. There is evidence to support the Toupe procedure, the posterior 270-degree wrap, as the procedure of choice. It has shown similar efficacy to the other techniques, with a decreased incidence of minor postoperative adverse effects such as gas-bloat and dysphagia. There is solid evidence for partial wraps to be done in patients with esophageal motility disorders.[18][19] Since the outcome differences are minor, most authors would recommend the surgeon perform the technique with which he or she is most comfortable.

Enhancing Healthcare Team Outcomes

Patients with GERD are usually followed by the primary care provider, internist, and nurse practitioner. Patients who have continuous symptoms should be referred to a gastroenterologist and thoracic surgeon for further workup. One of the procedures to restore the anatomy of the LES is the Nissen fundoplication. Today, the procedure can be done laparoscopically with minimal morbidity and mortality. New therapies for gastroesophageal reflux disease have been surfacing. The two most studied therapies are the transoral incisionless fundoplication and the magnetic sphincter augmentation device. These novel therapies have shown promising short-term results. All clinicians should be aware of these procedures while considering the treatment of gastroesophageal reflux disease.[20][21]