(Radiographics. 2002;22:305-322.)
© RSNA, 2002
Management of Visceral Interventional Radiology Catheters: A Troubleshooting Guide for Interventional Radiologists1
Michael M. Maher, MD, FRCSI, FFR(RCSI), FRCR,
Susan Kealey, MB, MRCPI, FFR(RCSI),
Ann McNamara, MB, FRCSI, FFR(RCSI),
Risteard O’Laoide, MB, MRCPI, FFR(RCSI), FRCR,
Robert G. Gibney, MB, FRCPI, FFR(RCSI), FRCR and
Dermot E. Malone, MD, MRCPI, FFR(RCSI), FRCR
1 From the Department of Radiology, St Vincent’s University Hospital, Dublin, Ireland. Recipient of a Cum Laude award for an education exhibit at the 2000 RSNA scientific assembly. Received April 19, 2001; revision requested July 6 and received September 18; accepted September 20. Address correspondence to M.M.M., Division of Abdominal Imaging and Interventional Radiology, Department of Radiology, Massachusetts General Hospital, White 270, 55 Fruit St, Boston, MA 02114.
 |
Abstract
|
|---|
Visceral interventional radiology catheters can be difficult to exchange or remove for a variety of reasons. These reasons include exit of the guide wire through the side holes of the catheter, blockage of the catheter, difficulty unlocking the pigtail, retention of the string after catheter removal, migration of the string ahead of the guide wire, catheter fracture, and snaring of an adjacent stent by the pigtail. Secure fixation of the catheter to the skin is important. A technique that allows secure fixation without direct puncture and suturing of the catheter to the skin is recommended. If a catheter falls out or is inadvertently removed, access can occasionally be regained and the catheter can be replaced without repuncture. The timing of catheter removal is based on the clinical condition of the patient and the daily output from the catheter. "Tractography" is a useful study before removal of any catheter that requires a mature tract for removal, particularly cholecystostomy catheters and transpleural catheters. In biliary catheter exchange, the most vital issue is the position of the side holes of the catheter. If an abscess cavity remains large after catheter drainage, the catheter can be repositioned or a second catheter can be placed.
© RSNA, 2002
Index Terms: Catheters and catheterization, **.126922 • Catheters and catheterization, complications, **.458 • Interventional procedures, **.1269 Interventional procedures, complications, **.458
|
LEARNING OBJECTIVES
|
|---|
After reading this article and taking the test, the reader will be able to:
- Describe problems in the exchange and removal of visceral interventional radiology catheters and ways of overcoming them.
- Describe methods of regaining access to an abscess, fluid collection, or obstructed system after inadvertent catheter displacement.
- Describe routine management of visceral interventional radiology catheters and discuss the important decisions that are made from the time of insertion to catheter removal.
|
Introduction
|
|---|
Techniques for catheter placement in interventional radiology are well described. Once the catheter is successfully placed, the next priority is maintaining the catheter in optimal position. The development of self-locking pigtail catheters has resulted in a reduced frequency of accidental catheter dislodgment and made the management of interventional radiology catheters much easier. These catheters are now used routinely in most situations that require drainage with interventional radiology, except when the abscess cavity or obstructed system being drained is not large enough to accommodate a pigtail catheter.
Once the catheter position is secure, the interventional radiologist should be alert to potential catheter-related problems. Although the benefits of self-locking pigtail catheters are widely accepted and these catheters are preferred for routine abscess drainage in most centers, use of these catheters is associated with additional difficulties, unique to self-locking pigtail catheters, that are usually associated with the internal self-locking mechanism. In experienced hands, the difficulties can usually be easily overcome. However, they may pose problems for interventional radiology trainees and can result in loss of access in extreme circumstances. Self-locking pigtail catheters can be difficult to exchange or remove for a variety of reasons, including difficulty unlocking the pigtail, exit of the guide wire through the side holes of the catheter, migration of the string inside the catheter and ahead of the guide wire, retention of the string after removal of the catheter, and snaring of an adjacent stent by the pigtail.
Other aspects of interventional radiology catheter management unrelated to self-locking pigtail catheters, including fixation of the catheter to the skin and catheter care and maintenance, are vitally important. The issues of the timing and technique of catheter removal require experience and training to avoid fundamental errors. There are specific problems related to the management of catheters in different locations, such as transperitoneal (cholecystostomy, biliary) and transpleural catheters. Management and removal of these catheters require specific attention.
This article addresses these issues with special emphasis on problems related to catheter exchange, removal, and displacement. The aim of the article is to describe safe and effective methods of catheter exchange and removal. Specific topics discussed are what to do when the catheter won’t come out, what to do when the catheter has come out inadvertently, and how to decide if the catheter should come out. Common problems encountered during exchange and removal of visceral interventional radiology catheters are described, and ways of avoiding and troubleshooting these problems are discussed. A simple, reliable method of securing catheters to the skin is described. As part of the discussion of management of transperitoneal and transpleural catheters, the indications for and technique of "tractography" prior to catheter removal are described. Finally, methods of regaining access in the event of inadvertent catheter displacement are described.
|
The Catheter Won’t Come Out
|
|---|
Techniques for Catheter Exchange and Removal
Once the patient is comfortable on the fluoroscopy table, the skin and the catheter are prepared by using standard sterile procedures. A scout radiograph is always obtained prior to catheter exchange. The scout radiograph should document the site of catheter entry through the patient’s skin. This documentation is achieved by placing a metal forceps over the site of catheter insertion. Also, the scout radiograph allows the image intensifier to be correctly positioned to allow a good field of view for catheter exchange and thus to prevent exposing the operator’s hands to radiation during the procedure. A small amount of dilute contrast material is injected through the catheter to assess catheter patency and to assess the size of the abscess cavity and the position of the catheter within the cavity or obstructed system being drained. The catheter is then unlocked by releasing the locking mechanism. Many operators favor cutting the catheter from the start, rather than releasing the locking mechanism, advancing a guide wire through the catheter, and then withdrawing the catheter over the guide wire under fluoroscopic guidance. A straight guide wire rather than a "J" guide wire should be used, as this reduces the chance of the guide wire migrating through the side holes of the catheter (Fig 1).
View larger version (86K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1a. Exit of a guide wire through a proximal side hole. (a) Radiograph shows a self-locking pigtail catheter that is unlocked. A straight, stiff guide wire exits through a proximal side hole (arrow). This problem is solved by withdrawing the guide wire back into the shaft of the catheter. An artery forceps is attached securely to the end of the guide wire, thus facilitating torque control. (b) Radiograph shows that the guide wire has been successfully manipulated through the end hole of the catheter.
|
|
View larger version (97K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1b. Exit of a guide wire through a proximal side hole. (a) Radiograph shows a self-locking pigtail catheter that is unlocked. A straight, stiff guide wire exits through a proximal side hole (arrow). This problem is solved by withdrawing the guide wire back into the shaft of the catheter. An artery forceps is attached securely to the end of the guide wire, thus facilitating torque control. (b) Radiograph shows that the guide wire has been successfully manipulated through the end hole of the catheter.
|
|
Once there is a sufficient length of guide wire within the system, the new catheter is advanced over the guide wire into the abscess or obstructed system. The stiff trocar of the pigtail is left within the shaft of the catheter until the catheter has traversed the skin and soft tissues and advanced just beyond the wall of the abscess or obstructed system. The metal trocar is then released from the catheter, and its position is maintained while the catheter is advanced over the metal trocar into the abscess or obstructed system under fluoroscopic guidance. In patients with well-established tracts, the metal trocar may not be necessary and the plastic stiffener may be all that is required to advance the catheter into the cavity. In patients with long-standing mature tracts, most catheters can be exchanged without the need for a metal trocar or plastic stiffener. Contrast material should be injected through the catheter at the end of the procedure to confirm optimal catheter position and ensure that all side holes are accurately placed within the abscess or obstructed system.
Problems Encountered during Catheter Exchange and Removal
Blockage of the Catheter.—
Catheters are more likely to occlude if the effluent consists of thickened or bloodstained material. Exchanging the blocked catheter is frequently challenging. Blocking of a catheter is usually detected following injection of contrast material through the catheter at the beginning of the procedure. A few techniques can be used to overcome the problem of the blocked catheter and allow successful catheter exchange. Warm sterile saline solution can be injected with force in an effort to remove debris from the blocked catheter. If the catheter remains blocked, probing the catheter with a range of guide wires from Glidewires (Terumo Medical, Somerset, NJ) to the stiff Amplatz guide wires (Cook, Bloomington, Ind) can unblock the catheter. Again, these maneuvers should be performed under fluoroscopic guidance to assess guide-wire progress and avoid losing access to the system.
If the catheter remains blocked, a sheath (peel-away sheath or vascular sheath) can be passed over the catheter and into the collecting system or abscess (Fig 2). Before the sheath can pass over the catheter, the end of the catheter needs to be cut off. Occasionally, the catheter is then too short to allow the sheath to pass over the catheter. To overcome this problem, a suture can be tied to the end of the catheter, over which the sheath can be placed on its way into the catheter tract. The sheath chosen should be at least 1-F larger than the blocked catheter. Once the sheath is within the system or abscess, contrast material is injected to confirm good position. The catheter is then withdrawn and a stiff guide wire is advanced into the system. Catheter exchange is then performed by using standard techniques.
View larger version (156K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2a. Exchange of a blocked catheter in a 60-year-old man with bladder cancer in whom bilateral ureteral catheters were placed. (a) Radiograph shows partial occlusion of an 8-F ureteral catheter, which prevents advancement of a guide wire (arrow). (b) Radiograph shows a 9-F peel-away sheath passed over the catheter and into the collecting system. (c) Radiograph shows the catheter straightened within the sheath. The catheter is then withdrawn. (d) Radiograph shows a similar 8-F catheter, which was advanced through the sheath. Good position of the catheter is confirmed with injection of contrast material, and the sheath is removed.
|
|
View larger version (148K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2b. Exchange of a blocked catheter in a 60-year-old man with bladder cancer in whom bilateral ureteral catheters were placed. (a) Radiograph shows partial occlusion of an 8-F ureteral catheter, which prevents advancement of a guide wire (arrow). (b) Radiograph shows a 9-F peel-away sheath passed over the catheter and into the collecting system. (c) Radiograph shows the catheter straightened within the sheath. The catheter is then withdrawn. (d) Radiograph shows a similar 8-F catheter, which was advanced through the sheath. Good position of the catheter is confirmed with injection of contrast material, and the sheath is removed.
|
|
View larger version (146K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2c. Exchange of a blocked catheter in a 60-year-old man with bladder cancer in whom bilateral ureteral catheters were placed. (a) Radiograph shows partial occlusion of an 8-F ureteral catheter, which prevents advancement of a guide wire (arrow). (b) Radiograph shows a 9-F peel-away sheath passed over the catheter and into the collecting system. (c) Radiograph shows the catheter straightened within the sheath. The catheter is then withdrawn. (d) Radiograph shows a similar 8-F catheter, which was advanced through the sheath. Good position of the catheter is confirmed with injection of contrast material, and the sheath is removed.
|
|
View larger version (139K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2d. Exchange of a blocked catheter in a 60-year-old man with bladder cancer in whom bilateral ureteral catheters were placed. (a) Radiograph shows partial occlusion of an 8-F ureteral catheter, which prevents advancement of a guide wire (arrow). (b) Radiograph shows a 9-F peel-away sheath passed over the catheter and into the collecting system. (c) Radiograph shows the catheter straightened within the sheath. The catheter is then withdrawn. (d) Radiograph shows a similar 8-F catheter, which was advanced through the sheath. Good position of the catheter is confirmed with injection of contrast material, and the sheath is removed.
|
|
Difficulty Unlocking the Pigtail.—
If the pigtail remains locked after release of the unlocking mechanism, this usually means that it is impossible to advance sufficient guide wire through the end hole of the catheter. Occasionally, advancing the guide wire in short, jerking movements while rotating the catheter in a clockwise or counterclockwise direction will unlock the mechanism and allow advancement of sufficient guide wire.
If this technique fails, the catheter should be cut. This usually successfully unlocks the loop of the pigtail catheter. Other less common causes of difficulty in unlocking catheters (Fig 3) are usually overcome by cutting the catheter and unlocking the self-locking mechanism. As much guide wire as possible is then advanced into the abscess cavity or system, and the catheter is withdrawn in increments over the guide wire under fluoroscopic guidance to ensure that access to the abscess cavity or obstructed system is not lost.
Retention of the String after Catheter Withdrawal.—
After catheter removal, the two ends of the string occasionally extrude through the catheter exit hole in the skin. This problem occurs more frequently if the catheter was unlocked by cutting the catheter rather than by unlocking the self-locking system.
This problem is usually resolved by holding one of the string ends in an artery forceps and then withdrawing the string. To avoid breaking the string, it is important to hold the string close to the skin and withdraw it in increments, adjusting the forceps so that it remains close to the skin as the string is removed. However, occasionally the string cannot be successfully removed with this technique.
The next step is to place a 5-F dilator over one end of the string and into the cavity under fluoroscopic guidance (Fig 4). If the length of string protruding from the skin is too short, the dilator cannot be passed over the string and into the catheter tract. In this situation, one end of the string may need to be extended by attaching a suture to it. Once the dilator is passed over the string and through the tract, the string usually detaches and can be withdrawn by retracting the longer end.
View larger version (140K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4a. What to do when the string is left behind. (a) Scout radiograph shows a nephrostomy tube before removal. The tube is cut and withdrawn. (b) Photograph shows that the locking string has been left behind. (c) Photograph shows that the string cannot be removed even by pulling on one end. (d) Photograph shows a 5-F dilator passed over the string and into the tract. The string detaches and is easily withdrawn.
|
|
View larger version (157K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4b. What to do when the string is left behind. (a) Scout radiograph shows a nephrostomy tube before removal. The tube is cut and withdrawn. (b) Photograph shows that the locking string has been left behind. (c) Photograph shows that the string cannot be removed even by pulling on one end. (d) Photograph shows a 5-F dilator passed over the string and into the tract. The string detaches and is easily withdrawn.
|
|
View larger version (150K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4c. What to do when the string is left behind. (a) Scout radiograph shows a nephrostomy tube before removal. The tube is cut and withdrawn. (b) Photograph shows that the locking string has been left behind. (c) Photograph shows that the string cannot be removed even by pulling on one end. (d) Photograph shows a 5-F dilator passed over the string and into the tract. The string detaches and is easily withdrawn.
|
|
View larger version (125K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4d. What to do when the string is left behind. (a) Scout radiograph shows a nephrostomy tube before removal. The tube is cut and withdrawn. (b) Photograph shows that the locking string has been left behind. (c) Photograph shows that the string cannot be removed even by pulling on one end. (d) Photograph shows a 5-F dilator passed over the string and into the tract. The string detaches and is easily withdrawn.
|
|
Migration of the String ahead of the Guide Wire.—
During exchange of a Cope-type catheter, if the internal self-locking string is cut before the guide wire is inserted, the guide wire can push the string down the catheter and cause it to "ball up" in the tapered lumen just proximal to the catheter tip. It then becomes very difficult to get the wire out the tip of the catheter. This complication is uncommon. It cannot occur if the guide wire is introduced to the tip of the catheter before the string is cut proximally. However, if the catheter is cut before the guide wire is advanced, this complication should not occur if the loose ends of the string are grasped in an artery forceps as the guide wire is advanced.
Catheter Fracture.—
Catheter fracture can result in a retained biliary or nephrostomy catheter fragment. There is disagreement between interventional radiologists as to whether retained fractured catheters need to be removed. One school of opinion suggests that when access to the system is maintained or regained and the system remains drained, the presence of a broken catheter is usually not of clinical significance. Other radiologists argue that these "foreign bodies" can act as a nidus for infection or stone formation even with a well-drained system.
Retrieval of fractured catheter fragments can be technically difficult. The first step is to regain access to the system in which the fractured catheter resides. Attempts should be made to access the system in a site that will allow easy access to the fractured catheter. Once secure access to the system is achieved and secured with an appropriate peel-away sheath, attempts are made to grasp the catheter so that it can be removed percutaneously through the sheath. A variety of instruments are available for grasping catheters, including snares, endoscopic biopsy forceps, and pigtail catheters. The sheath should be of sufficient caliber to allow easy retraction of the catheter through the skin without discomfort for the patient. Another function of the sheath is to maintain access to the system following removal of the catheter so that a replacement catheter can be placed following the procedure.
Maintaining the Catheter in Good Position
To maintain optimal catheter position, great care needs to be taken in securing the catheter to the skin. Many catheter fixation techniques have been described, and these vary between institutions (1,2). We advocate that one catheter fixation system be used by all staff in an interventional radiology department so that interventional radiology trainees and nursing staff are familiar with one technique.
We use and recommend the fixation technique described by Ho and colleagues (1) (Fig 5). This technique allows secure catheter fixation to the skin without the need for direct puncture and suturing of the catheter to the skin. This avoids pain during catheter fixation as well as morbidity associated with having suture material in the skin and soft tissues for long periods, including skin necrosis, infection, allergic reactions, and hypertrophic or keloid scarring. This technique involves suturing a 3/0 silk suture to a thin strip of elastic adhesive bandage (Elastoplast; Beiersdorf, Hamburg, Germany). The strip of elastic adhesive bandage is then secured in position near the exit point of the catheter by placing adhesive tape around the circumference of the elastic adhesive bandage. The silk suture is then securely tied to the catheter on a mesentery. A synthetic see-through adhesive material (Tegaderm; 3M Health Care, St Paul, Minn) is applied to the skin adjacent to the exit point of the catheter. The catheter is placed on the exterior surface of the see-through adhesive dressing and is then sandwiched between it and a second identical piece of see-through adhesive dressing. This maintains the catheter in position flush with the skin. The margins of this part of the fixation device are then secured to the skin with more adhesive tape placed around its circumference.
Catheters require regular close inspection to assess catheter position and the integrity of the catheter dressing and of the device securing the catheter to the skin. Orders should be written for catheter flushing at least twice per day by nursing staff on the floor. Catheter patency should be checked daily by the interventional radiology team by observing catheter outputs and by flushing of the catheter on interventional radiology rounds. If problems are encountered, early imaging can then be performed to increase the chance of catheter salvage. Daily inspection of catheters on interventional radiology rounds is essential to maintaining good catheter lifetimes and avoiding additional procedures. Recent radiologic images should be reviewed to assess catheter position and abscess cavity size and check for other important findings, such as loculation or development of a new collection. For patients with long-term catheters, education before discharge home and regular visits from the home nurse prevent catheters from falling out or becoming blocked. In addition, catheter checks by the interventional radiology team should be regularly scheduled and the catheter should be changed regularly. We typically exchange long-term drainage catheters once every 6 weeks.
|
The Catheter Has Come Out
|
|---|
If a catheter falls out or is inadvertently removed, access can often be regained and the catheter can be replaced without repuncture. The chances of success in this regard depend on the maturity of the tract and the time elapsed since the catheter fell out. Ideally, the patient should return to the fluoroscopy room within 24 hours. The area should be examined fluoroscopically to ensure that the entire catheter is out. A scout radiograph should be obtained. When lidocaine is given, care should be taken not to disturb the tract. Use of topical lidocaine gel rather than subcutaneous lidocaine is advised and is usually sufficient to achieve adequate local anesthesia. Following this, the tract is probed with a hydrophilic guide wire and progress along the tract is monitored with fluoroscopy (Fig 6). A 5-F catheter is then advanced over the guide wire; when access to the system has been regained, contrast material is injected to confirm good position within the cavity or abscess. The guide wire is then exchanged for a stiffer exchange guide wire, and a new catheter can be placed easily. Dilation of the tract is usually not necessary if the tract is well formed.
View larger version (120K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 6a. How to regain access after a nephrostomy tube has fallen out. (a) Radiograph shows probing of the tract with a hydrophilic guide wire. (b) Radiograph shows the progress of the guide wire along the tract, which is monitored with fluoroscopy. (c) Radiograph shows a 5-F catheter advanced over the guide wire. Contrast material is injected to confirm good position of the catheter within the renal pelvis. The guide wire is then exchanged for a stiffer "exchange" guide wire. (d) Radiograph shows a new catheter, which is placed easily.
|
|
View larger version (117K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 6b. How to regain access after a nephrostomy tube has fallen out. (a) Radiograph shows probing of the tract with a hydrophilic guide wire. (b) Radiograph shows the progress of the guide wire along the tract, which is monitored with fluoroscopy. (c) Radiograph shows a 5-F catheter advanced over the guide wire. Contrast material is injected to confirm good position of the catheter within the renal pelvis. The guide wire is then exchanged for a stiffer "exchange" guide wire. (d) Radiograph shows a new catheter, which is placed easily.
|
|
View larger version (131K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 6c. How to regain access after a nephrostomy tube has fallen out. (a) Radiograph shows probing of the tract with a hydrophilic guide wire. (b) Radiograph shows the progress of the guide wire along the tract, which is monitored with fluoroscopy. (c) Radiograph shows a 5-F catheter advanced over the guide wire. Contrast material is injected to confirm good position of the catheter within the renal pelvis. The guide wire is then exchanged for a stiffer "exchange" guide wire. (d) Radiograph shows a new catheter, which is placed easily.
|
|
View larger version (110K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 6d. How to regain access after a nephrostomy tube has fallen out. (a) Radiograph shows probing of the tract with a hydrophilic guide wire. (b) Radiograph shows the progress of the guide wire along the tract, which is monitored with fluoroscopy. (c) Radiograph shows a 5-F catheter advanced over the guide wire. Contrast material is injected to confirm good position of the catheter within the renal pelvis. The guide wire is then exchanged for a stiffer "exchange" guide wire. (d) Radiograph shows a new catheter, which is placed easily.
|
|
|
Should the Catheter Come Out?
|
|---|
Timing of Catheter Removal
Infected Fluid Collections.—
The most important factor in deciding to remove a catheter draining an infected collection is the clinical status of the patient. The major parameters that should be checked include (a) resolution of fever; (b) absence of leukocytosis or other septic parameters; (c) daily drainage via the catheter of less than 20 mL; and (d) catheter-related problems that might explain reduced output, such as catheter malposition, blockage, or kinking (Fig 7). Imaging features that favor catheter removal include demonstration of a small, well-drained cavity with no undrained compartments or loculi(Figs 8–10) at ultrasonography (US), computed tomography (CT), or sinography. There must be no evidence of a fistula at sinography. In this regard, it is reassuring to see a small volume of contrast material reflux back around the tube, confirming that the cavity has been fully opacified.
View larger version (70K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 7a. Catheter kinking in a 45-year-old woman with a large pancreatic pseudocyst. The output from the catheter was reduced. (a) Plain radiograph obtained with the patient in the prone position shows a kink in the catheter (arrow). (b) Radiograph obtained with injection of contrast material after elimination of the kink shows a large cavity.
|
|
View larger version (104K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 7b. Catheter kinking in a 45-year-old woman with a large pancreatic pseudocyst. The output from the catheter was reduced. (a) Plain radiograph obtained with the patient in the prone position shows a kink in the catheter (arrow). (b) Radiograph obtained with injection of contrast material after elimination of the kink shows a large cavity.
|
|
View larger version (135K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 8. Situation in which the catheter should come out. Radiograph obtained with injection of contrast material through a catheter positioned in an abscess in the right iliac fossa shows a small cavity with reflux around the tube. In such a case, it is safe to remove the catheter.
|
|
View larger version (150K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 9. Intermediate case (catheter removal depends on clinical factors). Radiograph obtained with injection of contrast material through a cholecystostomy catheter shows communication with the biliary tract through a patent cystic duct.
|
|
View larger version (152K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 10a. Situation in which the catheter should not come out. (a) Radiograph obtained with injection of contrast material through a catheter positioned in an abscess in the right iliac fossa shows a large cavity. (b) Radiograph obtained after injection of further contrast material shows opacification of the large intestine (arrows), a finding consistent with a colonic fistula. In such a case, do not remove the catheter.
|
|
View larger version (155K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 10b. Situation in which the catheter should not come out. (a) Radiograph obtained with injection of contrast material through a catheter positioned in an abscess in the right iliac fossa shows a large cavity. (b) Radiograph obtained after injection of further contrast material shows opacification of the large intestine (arrows), a finding consistent with a colonic fistula. In such a case, do not remove the catheter.
|
|
Noninfected Systems.—
Removal of catheters from noninfected systems (eg, "safety" catheters) again depends on the clinical status of the patient as well as the pattern of daily catheter outputs. Repeat imaging may be required to assess for residual or new collections. In most circumstances, 24-hour catheter output of less than 20 mL should be observed on at least two consecutive days prior to catheter removal. Catheter injection prior to removal should always be performed when a communication with the intestine, biliary tract, urinary tract, or pancreatic duct is suspected to avoid reaccumulation of the collection once the catheter is removed. The management of safety catheters is discussed later in this article.
Special Considerations for Both Infected and Noninfected Systems.—
If a catheter has been inserted into an infected collection or the biliary tract by the transpleural or transperitoneal route, it is prudent to have a mature tract before the catheter is removed. This is because of the potential for leakage of fluid from the biliary tract or infected cavity into the pleural cavity or for biliary peritonitis after biliary catheter removal. Some centers leave transpleural or transperitoneal catheters for 6 weeks to allow tract maturation and then remove the catheter. Other centers perform tractography and remove the catheter once the presence of a mature tract is confirmed. This technique is advocated in immunosuppressed patients or patients receiving steroids, as tract formation may be significantly delayed in these patients.
Technique of Tractography
Tractography is a useful study prior to the removal of any catheter that requires a mature tract prior to removal. This is particularly the situation in the case of cholecystostomy catheters and transpleural catheters.
In performing tractography, a stiff wire is placed through the indwelling catheter. The locking mechanism of the pigtail catheter is released and the catheter is withdrawn, leaving the guide wire within the cavity. A 5-F vascular sheath (with a side port for contrast material injection) is placed over the guide wire and into the cavity. The dilator component of the sheath is withdrawn over the guide wire. The sheath is then quickly withdrawn along the tract, with simultaneous injection of 20 mL of contrast material via the side port and acquisition of a series of digital images at three frames per second. The area is examined fluoroscopically for free flow of contrast material into the peritoneal or pleural cavity (Fig 11). If the tract is well formed, contrast material will outline the tract without free flow of contrast material into the peritoneal cavity (Fig 12), indicating that it is safe to remove the catheter.
View larger version (138K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 12. Negative tractogram. Radiograph obtained with injection into the catheter tract shows contrast material only within the tract (arrow) with no peritoneal or pleural leakage.
|
|
Cholecystostomy Catheters
Before removing cholecystostomy catheters, a tract between the gallbladder and the skin must have formed to avoid the risk of biliary peritonitis following removal. The experience of some centers suggests that a sufficient tract is formed after 3 weeks and that it is then safe to remove the catheter without the risk of peritonitis. Picus et al (3,4) described the case of a patient receiving steroid therapy who developed fatal biliary peritonitis after cholecystostomy catheter removal, even though the catheter had been in place for several months. We routinely perform tractography prior to cholecystostomy catheter removal.
Transpleural Catheters
In general, drainage of infradiaphragmatic abscesses by using the transpleural route is associated with a slightly increased complication rate but has a success rate similar to that of extrapleural drainage (5). The complications reported with transpleural drainage of subphrenic fluid collections include pneumothorax (22%) and inadvertent placement of catheters in the pleural space (11%) (5). Transpleural drainage of subphrenic collections can result in pleural empyema, although McNicholas et al (5) did not report development of empyema in 18 patients following transpleural drainage of subphrenic fluid collections. Although this complication is uncommon, it may occur, and it is therefore reasonable to advise that subphrenic fluid collections should be drained by using an extrapleural approach if at all possible.
There are situations in which transpleural drainage of abdominal collections cannot be avoided. Transpleural catheters predispose patients to seeding of infection along the catheter tract with resultant development of pleural empyema. If these catheters are removed before a satisfactory tract is formed, the chance of pleural infection is increased (Fig 13). Therefore, these catheters should be left in position longer than other catheters to allow a tract to form. Prior to removal, tractography should be performed, as in the case of cholecystostomy catheters.
View larger version (90K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 13. Pleural effusion after transpleural percutaneous drainage of a postoperative abscess in the left upper quadrant. Radiograph shows a left pleural effusion. It was treated with radiologic placement (under US guidance) of a 12-F radiologic chest drain, which was inserted as close as possible to the point where the abscess drainage catheter transgressed the pleural cavity.
|
|
Pancreatic Pseudocyst Catheters
We frequently perform transgastric drainage of pancreatic pseudocysts. Pancreatic pseudocyst catheters are usually left in situ, usually for a minimum of 6 weeks. The timing of catheter removal is based on the clinical condition of the patient and the daily output from the catheter. Noninfected pancreatic juice is usually clear, and persistent drainage of clear fluid from a pseudocyst catheter is usually indicative of communication with the pancreatic duct. However, prior to removal, CT of all patients is performed to confirm resolution of the pseudocyst and contrast material injection through the catheter is performed to confirm that the cavity is small and to assess for contrast material reflux into the stomach (Fig 14). In transperitoneal pancreatic pseudocyst drainage, persistent high output or communication with the pancreatic duct at sinography is an absolute contraindication to catheter removal. This is not the case with transgastric pancreatic pseudocyst drainage, provided a tract has formed between the pseudocyst and the stomach. Decisions about catheter removal in these circumstances are made by the surgeon and the interventional radiologist on a case-by-case basis, taking into account the patient’s preferences, tube management skills, clinical and social circumstances, and geographic location.
View larger version (115K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 14a. Use of pancreatic pseudocyst catheters (transgastric approach). (a) Radiograph obtained with injection of contrast material through the catheter shows a small pseudocyst cavity with reflux along the tract into the gastric lumen. There is no fistula to the pancreatic duct. (b) Radiograph obtained with injection of contrast material through the catheter in another patient shows a small pseudocyst cavity with a communication with the pancreatic duct (arrows). There is reflux along the tract into the gastric lumen. After this study, the catheter fell out, with no adverse results for the patient.
|
|
View larger version (113K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 14b. Use of pancreatic pseudocyst catheters (transgastric approach). (a) Radiograph obtained with injection of contrast material through the catheter shows a small pseudocyst cavity with reflux along the tract into the gastric lumen. There is no fistula to the pancreatic duct. (b) Radiograph obtained with injection of contrast material through the catheter in another patient shows a small pseudocyst cavity with a communication with the pancreatic duct (arrows). There is reflux along the tract into the gastric lumen. After this study, the catheter fell out, with no adverse results for the patient.
|
|
Biliary Catheters
Biliary catheter exchange potentially poses more technical challenges than exchange of any other interventional catheter. This applies to internal-external biliary catheters and to external biliary catheters. The most vital issue is the position of the catheter side holes. For external catheters, the catheter should be in such a position that the side holes are above the site of biliary obstruction but within the biliary system. If the side holes are outside the biliary system, this can lead to leakage of bile along the tract with subsequent biliary peritonitis or perihepatic biloma or to "back bleeding" from a portal venous or hepatic arterial communication.
Internal-external catheters must be exchanged very carefully. The position of the side holes in the new catheter must be identical to the position of the side holes in the old catheter. Once the old catheter is removed, the old and new catheters should be examined side by side to examine the position of the side holes. Extra side holes will frequently need to be placed in the new catheter to ensure that a sufficient number of side holes are positioned proximal to the site of biliary obstruction. Care needs to be taken not to weaken the catheter when creating the new side holes. Extra side holes should not be added if the catheter is less than 10 F in diameter to avoid weakening the catheter. Injection of contrast material at the end of the procedure is mandatory to confirm satisfactory internal and external biliary drainage. In addition, close attention should be paid to the periphery of the field to ensure that no contrast material is leaking along the catheter tract, which would indicate that the proximal side holes are outside the biliary system.
As a result of liver movements with respiration, biliary catheters have a propensity to back out of the biliary system. The risk of this complication can be reduced by using a stiff catheter (8-F Mueller catheter; Cook). This complication can still occur sometimes despite use of this type of catheter (Fig 15). Another solution is to use a softer catheter with a small locking pigtail (8.5-F Kumpe catheter; Cook). If the catheter is fixed to the skin, retraction of the catheter can occur and result in the catheter forming a loop between the liver and the anterior abdominal wall. The presence of such a loop makes catheter exchange very hazardous, as there is a risk of losing access to the biliary system as a stiff guide wire is advanced and tries to negotiate the loop. To overcome this problem, the catheter should be withdrawn under fluoroscopic guidance as the guide wire is advanced, thereby removing the loop from the catheter (Fig 16). The guide wire can then be advanced into the liver, thereby reducing the risk of losing access to the biliary system. Soft catheters without a locking pigtail should never be used for external biliary drainage.
View larger version (115K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 15a. Displacement of biliary catheters. (a) Radiograph shows a right-sided internal-external biliary drainage catheter that has backed out of the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. (b) Radiograph obtained in another patient shows a right-sided biliary catheter that has backed out of the biliary tract and is located in the peritoneal cavity.
|
|
View larger version (134K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 15b. Displacement of biliary catheters. (a) Radiograph shows a right-sided internal-external biliary drainage catheter that has backed out of the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. (b) Radiograph obtained in another patient shows a right-sided biliary catheter that has backed out of the biliary tract and is located in the peritoneal cavity.
|
|
View larger version (121K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 16a. How to reposition a displaced biliary catheter without losing access. (a) Radiograph shows a right-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. The tip of the catheter remains in the biliary tract. The presence of such a loop makes catheter exchange hazardous. (b) Radiograph shows how to advance a guide wire through the loop. The catheter is withdrawn as the guide wire is advanced. (c) Radiograph shows a left-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has formed a loop. (d) Radiograph shows the catheter being withdrawn as the guide wire is advanced.
|
|
View larger version (157K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 16b. How to reposition a displaced biliary catheter without losing access. (a) Radiograph shows a right-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. The tip of the catheter remains in the biliary tract. The presence of such a loop makes catheter exchange hazardous. (b) Radiograph shows how to advance a guide wire through the loop. The catheter is withdrawn as the guide wire is advanced. (c) Radiograph shows a left-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has formed a loop. (d) Radiograph shows the catheter being withdrawn as the guide wire is advanced.
|
|
View larger version (132K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 16c. How to reposition a displaced biliary catheter without losing access. (a) Radiograph shows a right-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. The tip of the catheter remains in the biliary tract. The presence of such a loop makes catheter exchange hazardous. (b) Radiograph shows how to advance a guide wire through the loop. The catheter is withdrawn as the guide wire is advanced. (c) Radiograph shows a left-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has formed a loop. (d) Radiograph shows the catheter being withdrawn as the guide wire is advanced.
|
|
View larger version (112K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 16d. How to reposition a displaced biliary catheter without losing access. (a) Radiograph shows a right-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has looped between the liver capsule and the abdominal wall. The tip of the catheter remains in the biliary tract. The presence of such a loop makes catheter exchange hazardous. (b) Radiograph shows how to advance a guide wire through the loop. The catheter is withdrawn as the guide wire is advanced. (c) Radiograph shows a left-sided external biliary drainage catheter that has backed out along the biliary tract; a segment of the catheter has formed a loop. (d) Radiograph shows the catheter being withdrawn as the guide wire is advanced.
|
|
Bleeding from Biliary Catheters
The risk of bleeding during initial biliary drainage or shortly after removal of a biliary catheter is reduced if the site of entry of the catheter into the biliary tract is as peripheral as possible. Central placement of biliary catheters increases the risk of portobiliary and arterial-biliary communications.
Bleeding during initial biliary drainage procedures usually occurs toward the end of biliary drainage or stent insertion, and the finding of heavy bleeding through the safety catheter or peel-away sheath should alert the interventional radiologist to the possibility of catheter side holes being outside the biliary tract with communication to the hepatic arterial or portal venous system. If the bleeding consists of dark blood, the likelihood is that the communication is with the portal venous system, whereas bright red pulsatile bleeding is suggestive of hepatic arterial communication. The treatment of portal venous back bleeding is to reposition the catheter so that there are no side holes outside the biliary tract. Arterial bleeding is more problematic. The first step is to place a large enough biliary drainage catheter to tamponade the bleeding site. Contrast material injection through the biliary catheter may demonstrate such a communication. If biliary catheter injection does not demonstrate a vascular communication, hepatic arteriography may be performed (Fig 17). Following this, there are two options: (a) Monitor the patient closely following the procedure; if the patient is in stable condition, leave the biliary catheter in place for 1 month and then recheck the patient’s status clinically and radiologically. (b) Perform immediate selective segmental hepatic arterial embolization.
View larger version (159K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 17a. Back bleeding from a biliary safety catheter following placement of a Wallstent. (a) Selective celiac arteriogram shows normal arterial anatomy with a biliary catheter, a Wallstent, and a guide wire in place. (b) Arteriogram obtained immediately after the catheter was drawn back over the guide wire during arteriography shows rapid arterial bleeding. Note how the lumen of the Wallstent fills with opacified blood (arrow).
|
|
View larger version (159K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 17b. Back bleeding from a biliary safety catheter following placement of a Wallstent. (a) Selective celiac arteriogram shows normal arterial anatomy with a biliary catheter, a Wallstent, and a guide wire in place. (b) Arteriogram obtained immediately after the catheter was drawn back over the guide wire during arteriography shows rapid arterial bleeding. Note how the lumen of the Wallstent fills with opacified blood (arrow).
|
|
Bleeding from the sinus tract is infrequently encountered following removal of a biliary catheter. Some interventional radiologists argue that prior to removal of a biliary catheter, pull-out tractography or cholangiography should be performed to examine the biliary tract and the sinus tract and to exclude a biliary-arterial communication. This is performed in a similar fashion to tractography. Contrast material is injected as the sheath is removed over the guide wire to determine if there is a communication between the biliary tract and the arterial or portal venous system. A portal venous communication is usually treatable by using pledgets to tamponade the tract peripheral to the communication. Arterial bleeding is usually more problematic and usually necessitates hepatic arteriography and selective segmental hepatic arterial embolization if active arterial bleeding is recognized.
Safety Catheters
Safety catheters are most frequently used in the biliary system following internal stent placement so that stent function can be assessed. Safety catheters are similarly used in the urinary tract following ureteric stent placement. Failure to place a safety catheter following stent placement predisposes the patient to the risk of biliary peritonitis or recurrent hydronephrosis or urinoma if the stent does not function satisfactorily. These safety catheters are usually left to gravity drainage for 24 hours following stent placement. At this stage, the stent is clamped and the patient is observed for signs of abdominal pain, fever, and drainage around the catheter. Should any of these findings be observed, the catheter is reopened. Safety catheters offer access to the ureter or biliary system for further intervention or can be left open permanently. Once a period of satisfactory clamping is completed, the catheter can be safely removed with the knowledge that the indwelling stent is functioning adequately.
When there is concern about the possible effects of catheter removal but on balance removal appears indicated (eg, a proximal biliary obstruction, high transpleural drainage), sealing the tract is a useful option. This can be done with absorbable gelatin sponge (Gelfoam; Pharmacia & Upjohn, Kalamazoo, Mich) delivered through a peel-away sheath or with opacified fibrin sealant (6) (Fig 18).
View larger version (132K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 18a. Sealing the tract of a biliary catheter with fibrin sealant in a patient with ascites. (a) Radiograph shows a Wallstent, which was placed transpleurally to palliate malignant obstruction of the distal common bile duct. An 8-F Mueller catheter was left in place as a safety catheter. The patient tolerated catheter clamping well. The catheter was removed within 48 hours. Because of the transpleural access and the ascites, radiopaque fibrin sealant (Tisseel; Baxter, Deerfield, Ill) was injected on an empirical basis. (b) Radiograph shows injection of the sealant between the point of entry to the biliary tract and the liver capsule and across the subphrenic space and chest wall. (c) Postprocedure radiograph shows satisfactory position of the sealant (arrow). There were no complications after catheter removal.
|
|
View larger version (112K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 18b. Sealing the tract of a biliary catheter with fibrin sealant in a patient with ascites. (a) Radiograph shows a Wallstent, which was placed transpleurally to palliate malignant obstruction of the distal common bile duct. An 8-F Mueller catheter was left in place as a safety catheter. The patient tolerated catheter clamping well. The catheter was removed within 48 hours. Because of the transpleural access and the ascites, radiopaque fibrin sealant (Tisseel; Baxter, Deerfield, Ill) was injected on an empirical basis. (b) Radiograph shows injection of the sealant between the point of entry to the biliary tract and the liver capsule and across the subphrenic space and chest wall. (c) Postprocedure radiograph shows satisfactory position of the sealant (arrow). There were no complications after catheter removal.
|
|
View larger version (130K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 18c. Sealing the tract of a biliary catheter with fibrin sealant in a patient with ascites. (a) Radiograph shows a Wallstent, which was placed transpleurally to palliate malignant obstruction of the distal common bile duct. An 8-F Mueller catheter was left in place as a safety catheter. The patient tolerated catheter clamping well. The catheter was removed within 48 hours. Because of the transpleural access and the ascites, radiopaque fibrin sealant (Tisseel; Baxter, Deerfield, Ill) was injected on an empirical basis. (b) Radiograph shows injection of the sealant between the point of entry to the biliary tract and the liver capsule and across the subphrenic space and chest wall. (c) Postprocedure radiograph shows satisfactory position of the sealant (arrow). There were no complications after catheter removal.
|
|
Snaring of an Adjacent Stent by the Pigtail
Particular caution needs to be taken when removing safety catheters located close to inter
Top
Abstract
LEARNING OBJECTIVES
