Abstract
Background
Swan-Ganz catheters are routinely used for monitoring of critically ill patients. These catheters can become knotted during the process of insertion, which can pose a challenge for removal.
Case Summary
A 63-year-old man underwent placement of a Swan-Ganz catheter, which was knotted and could not be removed. Ultimately, removal was achieved by tightening the knot in the Swan-Ganz catheter against the inlet of its sheath. The catheter and sheath were then pulled together out of the skin in a single motion.
Discussion
Multiple methods have been described to remove such knotted catheters although no consensus exists.
Take-Home Message
A knotted Swan-Ganz catheter can be safely removed by tightening the knot against the inlet of its sheath to reduce the knot size and then simply pulling the catheter and sheath together out of the skin.
Key Words: complication, imaging, x-ray fluoroscopy
Graphical Abstract
History of Presentation
This is a 63-year-old man who underwent coronary artery bypass grafting surgery. As per institutional standards, he had a Swan-Ganz catheter inserted before surgery after administration of general anesthesia in the operating room. Insertion of the catheter was guided with echocardiography (no fluoroscopy), and it was placed in the right jugular vein. Placement of the catheter was challenging although the final waveform tracing was satisfactory. Postoperatively, a routine chest radiograph in the cardiac surgery intensive care unit showed a knot in the Swan-Ganz catheter.
Take-Home Message
-
•
A knotted Swan-Ganz catheter can be safely removed by tightening the knot against the inlet of its sheath to reduce the knot size and then simply pulling the catheter and sheath together out of the skin.
Past Medical History
His past medical history includes coronary artery disease, dyslipidemia, and a remote smoking history.
Investigations and Differential Diagnosis
The diagnosis was made by a chest radiograph (Figure 1). This was confirmed on unsuccessful withdrawal of the pulmonary artery catheter into the sheath. Although the mechanism for knot formation may be multifactorial, it was thought that the knot developed because of looping within the right atrium or ventricle.
Figure 1.
Chest Radiographs Showing the Knotted Swan-Ganz Catheter
Management Options
There are multiple case reports of knotted Swan-Ganz catheters. Published methods of removal include both percutaneous and open surgical methods.1, 2, 3, 4, 5, 6, 7 Some have attempted injecting the Swan-Ganz catheter with cold saline to try uncoiling the knot based on the hydrostatic pressure of the injected fluid and its increased rigidity when cold.2 Insertion of a stiff wire through the lumen of the catheter to straighten it out and remove the knot has also been described.3 Some describe performing more invasive percutaneous methods such as inserting a wire through femoral venous access and inflating angioplasty balloons to 8 mm, 15 mm, and then 23 mm to progressively expand and undo the knot.1
Percutaneous snaring techniques have also been described.1,4,5 Mima et al4 describe inserting a new 5-F sheath in the right internal jugular vein and using a 10-mm Amplatz Goose Neck snare (Medtronic) to grasp the distal tip of the Swan-Ganz catheter through the loop of the knot and pulling it to untangle the knot. This was done after first placing a 0.014-inch guidewire (Cruise; Asahi Intecc) through the knot and using a 6-mm balloon (Rx-Genity; Kaneka) to expand the knot to allow enough space for the snare to go through the knot and grab the tip of the knotted catheter.4 Shang et al5 describe attempting a similar method but being unsuccessful at untangling the knot with that method. They resorted to obtaining femoral venous access and introducing a 14-F septal occluder delivery sheath (ODS-A-14F; Shanghai Shape Memory Alloy) into the right atrium.5 A snare was then introduced though the sheath to capture the knot of the catheter and then pull it into the sheath.5 Once the knot of the catheter was safely in the sheath, the proximal end of the Swan-Ganz catheter was cut at the skin in the neck, allowing the untangled top portion of the catheter to be removed at the neck, while the knotted portion was safely delivered into the septal occluder delivery sheath and removed through the femoral venous puncture site.5
Some of these case reports mention having unsuccessful attempts of catheter removal using percutaneous methods; however, a clear success rate of any one method cannot be ascertained because of the low frequency of this complication. In general, percutaneous procedures have low procedural risk, but they are not benign. Access site complications after percutaneous venous access for cardiovascular interventions have been reported to be 1.2% to 1.5%, with the most common complication being pseudoaneurysms, followed by arteriovenous fistulas, hematomas, and infections.6 The use of percutaneous interventions to remove knotted catheters also exposes the patient and medical staff to increased radiation due to the fluoroscopy used for these procedures. Using percutaneous interventions for knotted Swan-Ganz catheters is also likely to increase the amount of sedation the patient receives during their hospital stay and is likely to increase their overall recovery time.
The option of just pulling the Swan-Ganz catheter along with its sheath in the neck has also been described. Akkerhuis et al7 were able to do so by cutting out the original sheath and replacing it with a 12-F tracheostomy dilator (Cook, Ciaglia percutaneous tracheostomy introducer set, C-PTS-100; William Cook Europe AIS), then pulling on the Swan-Ganz catheter until the knot tightened at the tip of the dilator, and subsequently pulling both the catheter and dilator out simultaneously.7 Surgical exploration with either a surgical cutdown of the internal jugular vein or chest reopening with direct retrieval through the right atrium has also been described and is sometimes used because of failure of previously attempted percutaneous methods.1,8,9
Case Management
An initial attempt was made to remove the catheter in the intensive care unit. There was resistance as soon as the knot reached the tip of the sheath and it could not be removed. A multidisciplinary group of interventional radiology, interventional cardiology, and anesthesiology specialists reviewed the case to assess for percutaneous options to remove the catheter, but none were deemed suitable. A decision was made to take the patient back to the operating room to try to remove the knotted catheter in a controlled setting with the option of surgical intervention if needed. The patient was sedated, and local anesthetic was injected at the sheath insertion site. A 0.5-cm incision with a No. 11 blade scalpel was made at the insertion site of the sheath. The Swan-Ganz catheter was then pulled firmly against the sheath with adequate counter traction to reduce the outer diameter of the knot. With the catheter under maximal tension, a hemostat instrument was placed on the catheter against the sheath to maintain that tension. The catheter and sheath were then pulled together out of the skin. There was minimal resistance, and the Swan-Ganz catheter was successfully removed. Pressure and a suture were applied to the puncture insertion site. There was no bleeding or bruising at the puncture site after suture placement.
Discussion
The outcome was ideal as minimal intervention was needed with a simple noninvasive approach. The initial concern with simply pulling the Swan-Ganz catheter is that it would create a larger uneven hole in the jugular vein with the possibility of avulsing surrounding branches. However, the technique described here was able to significantly decrease the size and profile of the knot of the catheter to avoid this potential complication. To quantify the decrease in the size of the knot, we recreated the knot on the Swan-Ganz catheter that was initially seen on the chest radiograph and then measured the oval cross-sectional area along the axis of catheter removal (Figure 2). Before final tightening, the catheter had an oval shape with a 7.6 mm maximal diameter and 4.5 mm minimal diameter. The tightened knot removed from the patient had an oval cross-sectional area with a 4.9 mm maximal diameter and a 4.5 mm minimal diameter (Figure 3). This reduced knot diameter is much closer to the external diameter of the sheath, which was measured at 3.7 mm. This resulted in a knot profile much closer resembling that of the sheath, which was pulled out together with the Swan-Ganz catheter. The decreased knot size made it less likely to have the possible complication of avulsing surrounding venous branches during catheter removal.
Figure 2.
Images Showing Recreated and Actual Knots of the Swan-Ganz Catheter
The top image shows a recreated knot based on the chest radiograph images. This was used to measure a predicted knot size before tightening. The bottom image shows the actual knot of the Swan-Ganz catheter removed from the patient.
Figure 3.
Image of the Swan-Ganz Catheter Removed From the Patient
Conclusions
Swan-Ganz catheters have been reported to get knotted after insertion. This can result in difficulty in their removal with multiple reported methods. This case report describes the relative safety and simplicity in the method of tightening the knot in the catheter against the inlet of its sheath and removing the catheter and sheath together. In this case report, the Swan-Ganz catheter was easily and safely removed using this method.
Funding Support and Author Disclosures
The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
Footnotes
The authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the Author Center.
References
- 1.Matta A., Boudou N., Ohayon P., Carrié D. Angioplasty inflated balloon to unknot an entrapped Swan-Ganz catheter. Eur Heart J Case Rep. 2019;3(4):1–2. doi: 10.1093/ehjcr/ytz190. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Pugin D., Schmitz M., Bendjelid K. Difficult removal of a kinked swan-ganz catheter. J Cardiothorac Vasc Anesth. 2018;32(2):e41–e42. doi: 10.1053/j.jvca.2017.07.015. [DOI] [PubMed] [Google Scholar]
- 3.Katsikis A., Karavolias G., Voudris V. Transfemoral percutaneous removal of a knotted Swan-Ganz catheter. Catheter Cardiovasc Interv. 2009;74(5):802–804. doi: 10.1002/ccd.22201. [DOI] [PubMed] [Google Scholar]
- 4.Mima H., Enomoto S., Tamaki Y., Miyake M., Kondo H., Tamura T. Percutaneous removal of a knotted Swan-Ganz catheter. Cardiovasc intervention Ther. 2022;37(3):595–596. doi: 10.1007/s12928-021-00822-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Shang X.K., Yan Y., Wang B. Successful retrieval of a knotted Swan-Ganz catheter using interventional approach in an adult: a case report. Anaesthesiology Intensive Ther. 2016;48(5):367–370. doi: 10.5603/AIT.a2016.0048. [DOI] [PubMed] [Google Scholar]
- 6.Hetrodt J., Engelbertz C., Gebauer K., et al. Access site related vascular complications following percutaneous cardiovascular procedures. J Cardiovasc Dev Dis. 2021;8(11):136. doi: 10.3390/jcdd8110136. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Akkerhuis M.J.O., Bauland C.G., Voets A.J. Case report: percutaneous removal of a knotted pulmonary artery catheter using a tracheostomy dilator. Crit Care. 1999;3:131. doi: 10.1186/cc359. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.de Jesus Peixoto Camargo J., Marcantonio Camargo S., Noguchi Machuca T., Wagner P. Intraoperative removal of a knotted Swan-Ganz catheter during lung transplantation. Interactive Cardiovasc Thorac Surg. 2008;7(5):861–862. doi: 10.1510/icvts.2008.181339. [DOI] [PubMed] [Google Scholar]
- 9.Cohen S.M., Gold A.K., Augoustides J.G.T. Removal of a knotted swan ganz catheter in the superior vena cava after heart transplant-revisiting A rare complication of pulmonary artery catheter placement. J Cardiothorac Vasc Anesth. 2022;36(11):4221–4222. doi: 10.1053/j.jvca.2022.06.017. [DOI] [PubMed] [Google Scholar]