Upper extremity swelling in the hemodialysis (HD) dependent patient may be the result of multiple conditions. The evaluation of a vascular fistula or graft placed for hemodialysis is commonly initiated early on to identify potential abnormality or emergency.
Ultrasound is often sufficient to evaluate peripheral causes of arm swelling; however, it may fail to identify more proximal etiologies, such as thoracic outlet syndrome (TOS). Familiarity with differentials for upper extremity swelling in the HD dependent patient may be helpful in the ED, as the prevalence of end-stage renal disease (ESRD) continues to rise in the United States and now approaches 786,000 individuals.1
CASE REPORT
A 60-year-old male with a history of ESRD on HD presented to the ED with a complaint of one month of right upper extremity (RUE) swelling. Initial vital signs were heart rate 72 beats per minute; respiratory rate 18 breaths per minute; blood pressure 168/98 millimeters of mercury; temperature 37.3° Celsius; and oxygen saturation 100% on room air. The patient had a mature arterio-venous fistula (AVF) in the right arm and was sent to the ED from the dialysis center as the arm swelling appeared to worsen with each session of HD. He was unable to receive dialysis for the past several weeks as the dialysis center was unwilling to access the fistula in fear of worsening a possible AVF complication. Prior to this visit, the patient had been evaluated twice at an outside emergency department with an upper extremity ultrasound showing no abnormality within the arm or fistula. The patient’s swelling had progressively increased, resulting in severe pain and +2 pitting edema involving the digits up to the axilla.
A repeat RUE venous doppler study in our ED again demonstrated a patent AVF without thrombus. The decision to obtain a computed tomography (CT) of the chest with intravenous (IV) contrast was made for additional diagnostic information.
Image 1. Right upper extremity swelling with ipsilateral HD fistula
The CT chest demonstrated “venous stent overlying the proximal right subclavian and distal right brachiocephalic vein with severe narrowing at the area of the first rib, which appears to be causing impingement of the stent.” These findings were relayed to the patient, which prompted him to recall that he had previously undergone venous stenting 3 months earlier at a nearby facility.
The patient was admitted to the medicine service, with the nephrology and vascular surgery teams following for the primary diagnosis of vascular TOS. During his hospital stay, he received HD and interventional radiology guided stenting with improvement in his right subclavian vein stenosis and a significant reduction in his RUE swelling. Vascular surgery recommended treatment with aspirin and clopidogrel and transfer to a hospital with cardiothoracic surgery capabilities for first rib resection as a definitive treatment for venous TOS.
DISCUSSION
TOS is a relatively rare condition that can lead to severe swelling of the extremity distal to the site of stenosis. Diagnosis of this condition may be difficult as the site of stenosis can be located much more proximally. This often leaves ultrasound studies inadequate and necessitates the use of IV contrast, which may be contraindicated specifically in oliguric patients such as ours. TOS encompasses a group of disorders that occur when structures running between the first rib and collarbone (thoracic outlet) are compressed. It can be subcategorized into neurogenic, venous, or arterial, with neurogenic TOS being the most common, representing about 95% of cases. Venous TOS accounts for 3-5% of cases, and arterial TOS accounts for the final 1-2%.2
TOS can be caused by a variety of mechanisms, including trauma, repetitive motions, and anatomic variations. Venous TOS is recognized as a potential complication associated with AVF formation and is exacerbated by conditions unique to HD.3 Vascular grafts are associated with neointimal hyperplasia, marked by increased smooth muscle cell proliferation and increased luminal stenosis, additional factors such turbulent flow, and endothelial dysfunction are also contributory.4,5
Treatment of venous TOS is often necessary for the salvage of the AVF and requires venous stenting followed by decompression of the thoracic outlet through first rib resection.
Image 2. Venous thoracic outlet syndrome with stenting at site of severe stenosis
CONCLUSION
TOS is an important cause of arm swelling and fistula failure amongst ESRD and should be considered in ED settings. Due to the increased risk of coagulopathy with a high flow fistula, patients on hemodialysis are more likely to experience thrombosis and stenosis due to endothelial dysfunction and neointimal hyperplasia.6 Although limited data is present, there have been several clinical incidents in which patients have required thoracic outlet decompression for venous TOS associated with hemodialysis.7 In the workup of a painful and swollen arm with AV-fistula differentials should include both peripheral and central sources of swelling. In cases such as these, an upper extremity ultrasound is helpful in the diagnosis of pathology within the arm, but may have limited efficacy if the disease process extends proximally into the torso. This case demonstrates the importance of broadening our differentials, using high-quality clinical judgment with respect to history taking and examination, and involving our consultants early in order to accelerate the timing in which patients are treated since prior studies have suggested that a prolonged duration of symptoms is associated with poorer outcomes.8
REFERENCES
- United States Renal Data System. 2020 USRDS Annual Data Report: Epidemiology of kidney disease in the United States. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases. Bethesda, MD, 2020.
- Freischlag J and Orion K. Understanding thoracic outlet syndrome. Scientifica (Cairo). 2014;2014:248163.
- Seamus MM, Mohamad AH, Badr A, et al. First rib removal and decompression of the thoracic outlet as an indication to facilitate hemodialysis. J Vasc Surg Cases. 2016;2(3):111-113.
- Roumeliotis S, Mallamaci F, Zoccali C. Endothelial Dysfunction in Chronic Kidney Disease, from Biology to Clinical Outcomes: A 2020 Update. J Clin Med. 2020;23;9(8):2359.
- Bonatti J, Oberhuber A, Schachner T, et al. Neointimal Hyperplasia in Coronary Vein Grafts: Pathophysiology and Prevention of a Significant Clinical Problem. Heart Surg Forum. 2004;7(1):72-87
- Peden EK, Andraos E. Thoracic Outlet Syndrome in Hemodialysis Patients. In: Illig, K.A., et al. Thoracic Outlet Syndrome. Springer, Cham 2021;529-534.
- Davies MG, Hart JP. Venous thoracic outlet syndrome and hemodialysis. Front Surg. 2023;10:1149644.
- Illig KA, Gober L. Optimal management of upper extremity deep vein thrombosis: Is venous thoracic outlet syndrome underrecognized? J Vasc Surg Venous Lymphat Disord. 2022;10(2):514-526.