Sengstaken-Blakemore Tube

Anatomy and Physiology

Esophageal varices are most commonly the result of liver cirrhosis. As the hepatic tissue becomes scarred, the vasculature can become compressed and obstructed, leading to portal hypertension. Portal hypertension leads to increased pressure in the veins of the esophagus and stomach. The increased pressure results in the development of varices. Specifically, varices can develop in the para-esophageal collateral veins supplied from the azygos vein and short gastric veins supplied from the splenic vein.[4] 

Indications

Sengstaken-Blakemore tube placement is indicated for unstable patients with uncontrolled hemorrhage. In some instances, endoscopy is not available; however, even if it is available, it is not always successful. In both scenarios, Sengstaken-Blakemore tube placements can temporarily control the hemorrhage.[5][6] Another indication will be if there is a lack of available consultants or specialist physicians, such as in remote rural areas. The tube can be placed to stabilize the patient for transfer to a facility with a higher level of care. As previously stated, in all situations, the Sengstaken-Blakemore tube is only a temporizing rescue measure. Even if the initial hemorrhage is controlled by the balloon tamponade, over 50% of patients will rebleed when the device is deflated; therefore, a definitive treatment is always needed.[7]

Contraindications

The relative contraindications include known esophageal stricture and recent esophageal or gastric surgery. Both of these predispose the patient to an increased risk of esophageal rupture. However, Sengstaken-Blakemore tube placement is almost always a last resort option to control an unstable, massive hemorrhage. It is considered an emergent life-saving measure; therefore, the risks must be considered in that frame of reference.[8]

Equipment

Please note that while equipment and technique of balloon tamponade devices for esophageal varices are similar, this list is specific to Sengstaken-Blakemore tube placement. The most common tube types are the Sengstaken-Blakemore tube and the Minnesota tube, with the major difference being that the Minnesota tube has a larger gastric balloon and both gastric and esophageal aspiration ports. The Sengstaken-Blakemore tube only has an aspiration port for gastric contents; however, a double-lumen nasogastric tube used as an esophageal aspiration port. Further note that there are a few variations on the supplies required. It is possible to place the tube without Luer-locks and stopcocks by clamping the tubing with Magill forceps instead.[1]

• Blakemore
• Double lumen nasogastric tube
• 60 ml Luer-lock syringe
• 60 ml Slip-tip syringe
• 2 male Christmas tree Luer-lock converters
• 3 three-way stopcocks
• 3 Medlock caps
• Surgilube
• Manometer
• Roller-bandage
• 1 one-liter bag of intravenous fluids
• Optional: 2 ET tube securing devices
• Possibly: laryngoscope, Magill forceps

Personnel

An appropriately trained provider and an assistant.

Preparation

Airway protection remains the foremost focus. If the patient is requiring a Sengstaken-Blakemore tube placement, they have likely already been intubated for airway protection, but if not, endotracheal intubation should be performed prior to placement. Following intubation, the patient should be placed in the supine position with the head of the bed elevated to 45 degrees. If this position is not possible, the next best positioning is left lateral decubitus. Next, the gastric and esophageal balloon should be inflated to check for leaks. The balloons should then be fully deflated and lubricated. Nasogastric tube marking should be done prior to placement. Hold the distal end of the nasogastric tube 2 cm above the gastric balloon and mark at the level of the 50 cm line on the tube. Do the same 2 cm above the esophageal balloon. 

Technique or Treatment

It should be noted that there are variations for the placement of the tube; however, there are some critical steps that should be performed without any deviation from the protocol. These critical steps involve the balloon inflation volumes and/or pressures and the need for interval placement confirmation with a plain film.[9][10][11][1]

1. Insert the lubricated and fully deflated Sengstaken-Blakemore tube orally using a similar technique to orogastric tube placement. Stop once at the 50 cm mark on the tube. Markings should be facing the patient's right for proper balloon orientation. 
2. Test placement location by using a slip syringe and auscultating over the lungs and gastric region. If properly in the stomach, inflate the gastric balloon with 50 ml air through the gastric port. 
3. Get a chest x-ray or a kidney, ureter, and bladder (KUB) x-ray to confirm the gastric balloon is in the stomach before inflating any further. This is a key step that should not be skipped.
4. Once confirmed to be in the stomach, inflate with an additional 200 ml of air for a total of 250 ml of air in the gastric balloon.
5. Apply traction to the device. Using roller bandage and 1-liter intravenous (IV) fluid bag suspended over an IV pole, which will apply 1 kg of traction. Mark the depth of the tube at the mouth immediately after traction is applied. The tube should stretch slightly over the next 10 minutes as it warms to body temperature. It should not stretch more than 1 inch approximately, which is why the depth of the tube is marked at the beginning. If it moves more than an inch, consider the possibility of a hiatal hernia and balloon migration out of the gastroesophageal junction, which should be evaluated with an x-ray. If it moves less than 1 inch at the completion of stretching, the tube can be secured with ETAD under the same traction. 
6. Then perform gastric suction followed by a rinse and repeat aspiration. This checks for bleeding below the gastric balloon.
7. To assess for bleeding above the gastric balloon, use the premarked nasogastric tube. If there is continued bleeding, the esophageal balloon should be inflated. 
8. Using a manometer, inflate the esophageal balloon through the esophageal port with 30 mmHg. If bleeding continues, the pressure can be increased to a maximum of 45 mmHg. 

Complications

This procedure is detailed and rarely performed, that being said, complications do occur and can be serious. The most significant complications include airway obstruction, esophageal rupture, and aspiration pneumonitis.[12][13][9]

Clinical Significance

A competent emergency medicine provider should be able to stabilize and treat all emergent and life-threatening disease processes. A Sengstaken-Blakemore tube is one of the only stabilizing procedures for an esophageal variceal hemorrhage. It is of utmost clinical importance that emergency medicine physicians are capable of performing this procedure. 

Enhancing Healthcare Team Outcomes

Many emergency departments are transitioning to protocols and flowcharts for frequently seen emergencies. This is common for ST-segment elevation myocardial infarctions and cerebral vascular accidents. Similarly, gastrointestinal bleeds are also frequently seen in the emergency department and can deteriorate rapidly. Having an interprofessional team-based approach and protocol for massive gastrointestinal hemorrhage in the emergency department can be lifesaving and create a low-stress, efficient work environment for the entire team. Being familiar with not only the procedure but also what equipment and devices the hospital stocks will save time when it matters the most. Interprofessional communication between physicians and nurses is essential for both placement of the Sengstaken-Blakemore tube and recognizing complications throughout the procedure.