Estimation of brachial artery volume flow by duplex ultrasound imaging predicts dialysis access maturation

Objective:We developed a duplex ultrasound simulator and used it to assess accuracy of volume flow measurements in dialysis access fistula (DAF) models.Methods:The simulator consists of a mannequin, computer, and mock transducer. Each case is built from a patient’s B-mode images that are used to create a 3-dimensional surface model of the DAF. Computational fluid dynamics is used to determine blood flow velocities based on model vessel geometry. The simulator displays real-time B-mode and color-flow images, and Doppler spectral waveforms are generated according to user-defined settings. Accuracy was assessed by scanning each case and measuring volume flow in the inflow artery and outflow vein for comparison with true volume flow values.Results:Four examiners made 96 volume flow measurements on four DAF models. Measured volume flow deviated from the true value by 35 ± 36%. Mean absolute deviation from true volume flow was lower for arteries than veins (22 ± 19%, N = 48 vs. 58 ± 33%, N = 48, p < 0.0001). This finding is attributed to eccentricity of outflow veins which resulted in underestimating true cross-sectional area. Regression analysis indicated that error in measuring cross-sectional area was a predictor of error in volume flow measurement (β = 0.948, p < 0.001). Volume flow error was reduced from 35 ± 36% to 9 ± 8% ( p < 0.000001) by calculating vessel area as an ellipse.Conclusions:Duplex volume flow measurements are based on a circular vessel shape. DAF inflow arteries are circular, but outflow veins can be elliptical. Simulation-based analysis showed that error in measuring volume flow is mainly due to assumption of a circular vessel.

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Giant brachial artery aneurysm as a rare complication of a dialysis shunt

The Journal of Vascular Access ◽

10.1177/1129729819886746 ◽

2019 ◽

Vol 21 (5) ◽

pp. 799-802 ◽

Cited By ~ 1

Author(s):

Elisa Maria Schilling ◽

Malte Weinrich ◽

Thomas Heller ◽

Sebastian Koball ◽

Andreas Neumann

Keyword(s):

Brachial Artery ◽

Rare Complication ◽

Artery Aneurysm ◽

Giant Aneurysm ◽

Magnetic Resonance Imaging Scan ◽

Dialysis Access ◽

Large Tumor ◽

Arteriovenous Fistulas ◽

Arteriovenous Shunts ◽

Ongoing Care

Our patient exhibited a large tumor on his right upper arm where his former dialysis access site had been. X-ray, Doppler ultrasound, and magnetic resonance imaging scan could not fully reveal the nature of that tumor. Eventually, a surgical approach showed a giant aneurysm of the inflowing brachial artery to a partially obliterated arteriovenous fistula. This case highlights the importance of ongoing care for patients with arteriovenous shunts. Even arteriovenous fistulas, that are obliterated or no longer in use, can, especially when immunosuppressant therapy and other vascular risk factors are added to the overall cardiovascular risk, transform and endanger the health of our patients.

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Treatment of pediatric supracondylar humerus fractures accompanied with pink pulseless hands

BMC Musculoskeletal Disorders ◽

10.1186/s12891-020-03877-z ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Li-wei Xie ◽

Juan Wang ◽

Zhi-qiang Deng

Keyword(s):

Brachial Artery ◽

Closed Reduction ◽

Duplex Ultrasound ◽

Humeral Fractures ◽

Percutaneous Pinning ◽

Radial Pulse ◽

Color Flow ◽

Surgical Exploration ◽

Close Observation ◽

Supracondylar Humeral Fractures

Abstract Background The optimal treatment for pediatric supracondylar humeral fractures accompanied with a pink pulseless hand is controversial. Some clinicians recommend close observation after closed reduction and percutaneous pinning of the fractures, while some recommend surgical exploration if the radial pulse is unpalpable. The present study aimed to analyze the benefits and outcomes of close observation for treating pediatric supracondylar humeral fractures with a pink pulseless hand. Methods Thirteen consecutive children presenting with a pink pulseless hand following supracondylar humeral fracture were enrolled in this study. Preoperative and postoperative color-flow Duplex ultrasound detection was used to assess brachial artery compromise in most cases. Urgent closed reduction and percutaneous pinning of the fractures were attempted first. Close observation was carried out when the hand was pink and pulseless with an absent radial pulse. Results Preoperative color-flow Duplex ultrasound showed no disruption of the brachial artery in cases detected. Compression of the artery by the proximal fragment was observed in most cases, with one case of entrapment of the artery between fragments, and thrombus considered in two cases. All cases underwent urgent surgery, after which nine experienced immediate return of the radial pulse. The remaining four without a palpable pulse were managed with close observation and no deterioration of the vascular status was observed; therefore, no surgical exploration was performed. Postoperative color-flow Duplex ultrasound revealed continuity of the artery and rich collateral circulation. Patients completed an average of 4.5 years of follow-up, during which no major complications occurred. All patients achieved excellent limb function. Conclusions Our study demonstrates that close observation after urgent closed reduction and percutaneous pinning is a sufficient approach for the treatment of pediatric supracondylar humeral fractures accompanied with a pink pulseless hand. Surgical exploration is not necessary as long as the hand is warm and well perfused. Color-flow Duplex ultrasound is beneficial for assessing vascular compromise and determining treatment strategies.

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