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Core Interventional Radiology Review - Self Assessment Questions Volume 2

Core Interventional Radiology Review - Self Assessment Questions Volume 2

Jay A. Requarth

 

Verlag BookBaby, 2015

ISBN 9781483548715 , 274 Seiten

Format ePUB

Kopierschutz DRM

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9,89 EUR


 

Question 4.1.1:
A patient with a recently placed pull through gastrostomy tube returns with the complaint that he can no longer infuse tube feedings into the G-tube. He appears dehydrated and there is a tender area around the G-tube site. The contrast enhanced abdominal CT is shown. What is the most correct statement?
A. The G-tube balloon has broken.
B. The G-tube catheter is clogged with hardened feeding material.
C. The G-tube can be removed and replaced without image-guidance.
D. The gastrostomy tract may be completely occluded and a new site may need to be chosen.
4.1.1: The most correct statement is D. The gastrostomy tract may be completely occluded and a new site may need to be chosen.
This patient has the buried bumper syndrome. His bumper retention device has been pulled partly out and the tract to the stomach has closed. There is also an associated subcutaneous abscess.
This is probably the patient’s original G-tube, which was a pull-through device. Pull-through devices can be placed endoscopically (PEG-tubes) and radiologically. It takes quite a bit of effort to pull out a bumper retention device. This patient may be demented and either the patient (or his caregivers) inadvertently pulled out the tube. This is a common problem that occurs after placing G-tubes in demented patients.
The best treatment is to remove the existing G-tube and let the tract and abscess heal. Then place a new G-tube at a later time.
Question 4.1.2:
A patient with a partially obstructing upper esophageal squamous cell carcinoma is sent for a G-tube. The radiology technician helping you with the case asks you what type of device you want for the PEG. What do you tell him/her?
A. Pull-through high profile balloon retention G-tube
B. Pull-through low profile bumper retention G-tube
C. Push-in high profile balloon retention G-tube
D. Push-in low profile bumper retention G-tube
E. Refuse to perform the procedure as pre-operative feeding does not improve survival and the G-tube will make the stomach unusable for a gastric interposition. The surgeon can place a feeding jejunostomy tube during the esophageal resection and gastric interposition surgery.
4.1.2: The most correct answer is C. Push-in high-profile balloon retention G-tube.
Most upper esophageal squamous cell carcinomas are now treated with radiation with or without post-XRT resection. Early institution of enteric feeding improves survival in esophageal cancer patients. Previously placed G-tubes do not prevent gastric interposition; in fact, the stomach is often tailored into a tube to make the interposition easier. So, answer E is wrong on all counts.
You need to know the difference between a high profile vs. low profile (button) device and balloon retention vs. bumper retention. For placement only, balloon-retention devices are pushed in; whereas, bumper-retention devices are pulled in or through.
Soapbox alert!
Interventional radiologists don’t place PEG tubes. PEG is an acronym that means “percutaneous endoscopic gastrostomy” tubes. Interventional radiologists place “image-guided” or “radiologically-placed” gastrostomy tubes.
Patients with fungating esophageal tumors should have a push-in device (necessitating a balloon-retention device).
Active patients generally like low profile, button devices because they are easily hidden under their clothes. Bed-ridden patients usually keep their high profile device because it is easier to give tube-feeds via a high profile device.
Currently, a low profile push-in device is available. I have found this device to be dangerous as the low profile device can be deployed outside the stomach. An unpublished and non-peer reviewed review of over 200 G-tube placements found the mortality risk of low-profile balloon retention push in devices to be 10% (all by peritonitis due to infusing tube feeds outside the stomach) as compared to a 0% mortality for those patients being given a high-profile bumper retention or high profile balloon retention push-in device. Our group no longer uses these tubes on index placement procedures.
The sagittal image given below demonstrates a poorly placed low profile balloon retention G-tube. The balloon is inflated outside the stomach and tube feeds (and iodinated contrast) are being infused into the peritoneum. Furthermore, the stomach has a 24 French hole that is also leaking into the peritoneum. In these frail patients, this is usually a fatal complication.
Another Soapbox Alert!
High-profile bumper retention G-tubes are extremely painful to remove. Pulling these devices is one of the most personally dissatisfying procedures, which is why I generally place a high-profile balloon retention push-in device during the index procedure. Deflating the balloon and removing the tube is generally painless.
Question 4.1.3:
A patient has a long-standing G-tube because of dysphagia and aspiration that occurred after head and neck surgery for early stage tonsillar cancer. The patient now has leakage and a very tender area around the G-tube insertion site. What is the appropriate treatment?
A. Balloon dilation of the pylorus; maintain the same size G-tube
B. Place a G/J-tube
C. Remove the G-tube and let the site heal. Plan to place a new G-tube in the future.
D. Have the wound care consultants (ostomy nurse) see the patient and prescribe a skin barrier, anti-fungal powders, and antibiotic cream.
4.1.3: The most correct answer is A: Balloon dilation of the pylorus; maintain the same size G-tube.
This patient has gastric outlet obstruction (GOO) most likely due a non-relaxing pylorus due to vagal nerve dysfunction. See the figure below. Tube feeding, saliva, and gastric secretions fill the stomach, but cannot exit because the pylorus will not relax. The result is leakage of highly acidic fluid onto the skin, which causes a chemical burn. Should a larger G-tube be placed to stop the leakage (a temporary fix at best), reflux and aspiration will occur.
If you place a G/J-tube the patient will still have GOO. Saliva and gastric secretions will still fill the stomach; thus, leakage and reflux will continue to occur. Furthermore, switching a patient from G-tube feedings (bolus feeding) to G/J-tube feedings (continuous low-volume feeding that require a specialized pump) is a significant burden on the patient and family members. Therefore, the best option is to dilate the pylorus with a 20 mm in diameter balloon and continue try the G-tube feedings.
If this fails to stop the leakage, the next step is to place a G/J-tube; however, the G-tube port will need to be aspirated periodically to decompress the stomach. Medications should be changed to a liquid formulation if possible; all other non-extended release medications need to be crushed and mixed with water. Extended release tablets should never be crushed because the patient would receive an excessively high dose because a dose intended to be absorbed over a prolonged period of time would be absorbed in a short period of time. Medications should be given via the G-tube into the stomach because the bioavailability is known for gastric delivery not jejunal delivery.
The image below is an abdominal radiograph depicting a migrated high-profile G-tube. The patient was admitted through the emergency room with vomiting and aspiration. Gee, I wonder why?
The sad thing was that the patient was admitted for several days before he/she was referred to interventional radiology. A fluoroscopic procedure was performed to document the problem.
Question 4.1.4:
A patient with head-and-neck cancer is seen in the emergency room of your hospital. The patient is complaining of abdominal pain with nausea and vomiting. The ER physician ordered an abdominal CT. Two axial images are given below. The ER physician calls you because of a malfunctioning gastrostomy tube. Select the single best response.
A. The patient has a proximal small bowel obstruction and needs to have the gastrostomy tube placed to external drainage.
B. The G-tube should be replaced electively in the next week.
C. The G-tube should be pulled back without deflating the balloon to prevent accidental removal.
D. The G-tube should be deflated, pulled back, then re-inflated.
E. The patient needs a gastrojejunostomy tube.
4.1.4: The correct answer is D: The G-tube should be...