Esophageal Varices Treatment
Overview of the Principles and Techniques of the Major Treatment Modalities
Endoscopic Therapy
Endoscopic Therapy
Endoscopy is the cornerstone of the management of gastrointestinal hemorrhage both as a diagnostic and as a therapeutic modality. Once esophageal varices are identified as the source or likely source of bleeding, endoscopic options for treatment include injection sclerotherapy and variceal band ligation. Although these techniques do not treat the underlying portal hypertension, they have been shown to be effective in controlling variceal hemorrhage. The rates of success and complications of these endoscopic techniques depend in part on the experience of the operator and the technique employed.
Endoscopic Sclerotherapy
A variety of techniques have been employed in performing endoscopic sclerotherapy (EST) with the goal of arresting acute bleeding and preventing recurrent bleeding through the obliteration of varices by repeated injections. Injections may be directed into the veins (intravariceal injection) or into the esophageal wall adjacent to the variceal channels (paravariceal injection). Both techniques are effective, but intravariceal injection is more widely employed.Additionally, several different sclerosants are available, including 5% sodium morrhuate, 1% to 3% sodium tetradecyl sulfate (used in the United States), 5% ethanolamine oleate, 0.5% to 1% polidocanol (used in Europe), and absolute alcohol. Adhesives such as N-butyl-2- cyanoacrylate (tissue glue) have been used successfully. An optimal sclerosant for EST has not emerged; however, there are potentially important differences among these agents. For example, 1.5% sodium tetradecyl sulfate may be associated with more local ulceration and stricturing than polidocanol or ethanolamine oleate. The optimal volume of sclerosant to inject during a single session of EST is controversial. Typically 1 to 2 ml of sclerosant is used per injection and total volumes in the range of 10 to 15 ml seem to be optimal with regard to efficacy and safety.
The appropriate interval for performing follow-up EST after control of the initial hemorrhage also remains somewhat arbitrary. After the initial injection to control bleeding, a follow-up session 2 to 3 days later is common practice, usually followed by weekly or biweekly procedures until variceal obliteration is achieved. Thereafter, surveillance for reappearance of varices is usually conducted at intervals that extend from 1 month to 3 months and then 6 months. However, EST may be performed according to a variety of schedules, depending on patient tolerance, response to EST, and the development of sclerotherapy ulcers or other complications.
Endoscopic Variceal Ligation
The relatively high frequency of complications after EST (discussed later) led to the development of an alternative endoscopic therapy, endoscopic variceal ligation (EVL), also referred to as variceal banding.This technique was developed on the basis of principles established for the banding of hemorrhoids and involves the placement of elastic O ring ligatures on the varices, thereby causing strangulation of the veins . The original EVL device allowed only one band placement at a time, and the endoscope had to be removed to reload a new band after each ligation. Consequently, a plastic over tube was required to facilitate repeated esophageal intubation. Newer multiple-band devices have now replaced the original single-band device, thereby allowing the deployment of 6 to 10 rubber bands with a single esophageal intubation. Despite the improved technology, the use of EVL in the actively bleeding patient is still challenging because the plastic cylinder that carries the bands at the tip of the endoscope limits the operators field of vision. EVL is typically begun at the level of the gastroesophageal junction with additional bands deployed proximally. An endoscopic technique for EVL reported in 1999 that preserves the operators field of vision and employs detachable snares awaits further evaluation.
Endoscopic Sclerotherapy
A variety of techniques have been employed in performing endoscopic sclerotherapy (EST) with the goal of arresting acute bleeding and preventing recurrent bleeding through the obliteration of varices by repeated injections. Injections may be directed into the veins (intravariceal injection) or into the esophageal wall adjacent to the variceal channels (paravariceal injection). Both techniques are effective, but intravariceal injection is more widely employed.Additionally, several different sclerosants are available, including 5% sodium morrhuate, 1% to 3% sodium tetradecyl sulfate (used in the United States), 5% ethanolamine oleate, 0.5% to 1% polidocanol (used in Europe), and absolute alcohol. Adhesives such as N-butyl-2- cyanoacrylate (tissue glue) have been used successfully. An optimal sclerosant for EST has not emerged; however, there are potentially important differences among these agents. For example, 1.5% sodium tetradecyl sulfate may be associated with more local ulceration and stricturing than polidocanol or ethanolamine oleate. The optimal volume of sclerosant to inject during a single session of EST is controversial. Typically 1 to 2 ml of sclerosant is used per injection and total volumes in the range of 10 to 15 ml seem to be optimal with regard to efficacy and safety.
The appropriate interval for performing follow-up EST after control of the initial hemorrhage also remains somewhat arbitrary. After the initial injection to control bleeding, a follow-up session 2 to 3 days later is common practice, usually followed by weekly or biweekly procedures until variceal obliteration is achieved. Thereafter, surveillance for reappearance of varices is usually conducted at intervals that extend from 1 month to 3 months and then 6 months. However, EST may be performed according to a variety of schedules, depending on patient tolerance, response to EST, and the development of sclerotherapy ulcers or other complications.
Endoscopic Variceal Ligation
The relatively high frequency of complications after EST (discussed later) led to the development of an alternative endoscopic therapy, endoscopic variceal ligation (EVL), also referred to as variceal banding.This technique was developed on the basis of principles established for the banding of hemorrhoids and involves the placement of elastic O ring ligatures on the varices, thereby causing strangulation of the veins . The original EVL device allowed only one band placement at a time, and the endoscope had to be removed to reload a new band after each ligation. Consequently, a plastic over tube was required to facilitate repeated esophageal intubation. Newer multiple-band devices have now replaced the original single-band device, thereby allowing the deployment of 6 to 10 rubber bands with a single esophageal intubation. Despite the improved technology, the use of EVL in the actively bleeding patient is still challenging because the plastic cylinder that carries the bands at the tip of the endoscope limits the operators field of vision. EVL is typically begun at the level of the gastroesophageal junction with additional bands deployed proximally. An endoscopic technique for EVL reported in 1999 that preserves the operators field of vision and employs detachable snares awaits further evaluation.
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