Statistics from Altmetric.com
A 60-year-old woman with stage IIIC invasive squamous cell carcinoma of the anal canal underwent implantation of the left subclavian venous access device in preparation for administration of concurrent chemotherapy and radiotherapy. On the day of her first infusion, the catheter was accessed, aspirated but without blood return. Additionally, severe resistance was encountered when the catheter was flushed with saline. Chemotherapy was postponed. Venographic examination revealed an intact device without fracture or malposition. Despite that, the device continued to be dysfunctional. Interestingly, it was noted that saline could be flushed easily when the arms and neck were flexed and a great resistance was encountered when they were extended. Additionally, some swelling was noted superior to the catheter when the catheter was flushed with saline. Chemotherapy was again held. A review of the previously performed chest X-ray and CT revealed a slight narrowing of the catheter as it runs within the thoracic outlet (figures 1 and 2). The diagnosis of the pinch-off syndrome (POS) was made and the device was removed. A new device was placed on the right side more laterally. The new catheter was functional and could easily be flushed.
POS is a rare disorder where the central venous catheter (CVC) within the subclavian vein is pinched within the thoracic outlet between the clavicle and the first rib (figure 2). POS is specifically associated with the infraclavicular approach of implantation, particularly when the catheter is placed more medially. It is thought to be less common on the left side due to the obtuse angle of the left subclavian vein. POS should be suspected when there is a positional change in catheter function with neck and arm movement as the thoracic outlet widens and narrows. Symptoms tend to occur earlier when the CVC is used for high-volume and/or continuous infusions. This small gap between the clavicle and the first rib is mechanically compressed in POS resulting in shearing forces that can result in catheter fragmentation.1 Although chest X-ray may display a catheter kink, narrowing or fracture, normal imaging does not rule out the diagnosis of POS. Catheter injection with contrast is recommended to identify any catheter leak or malposition.2 Mild POS can be asymptomatic, is often found incidentally and can be observed. In a more severe form, the catheter should be promptly removed to avoid serious complications. Unrecognised POS can result in catheter fracture, which can lead to fatal cardiac arrhythmias when the catheter fragments embolise the heart. POS can often be avoided when the CVC is placed more laterally or if the internal jugular approach is employed.1 2
Pinch-off syndrome (POS) is a rare and potentially life-threatening complication of implantable central venous catheters
POS should be suspected when the catheter function changes with neck and arm movements, which occurs due to compression of the subclavian vein within the thoracic outlet
When POS is clinically suspected, the catheter should be promptly removed to avoid life-threatening complications such as catheter fracture and embolisation of its fragments
Contributors TH: wrote the initial draft, reviewed, edited and submitted this this manuscript. he also cared for this patient. MH: reviewed and edited the manuscript and cared for the patient. AZ: reviewed and edited the manuscript and cared for the patient. NJ: prepared the images, cared for this patient and reviewed and edited this manuscript.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient consent for publication Obtained.
Provenance and peer review Not commissioned; externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.