Fellows' Forum Fellows’ Forum in Dialysis edited by Mark A. Perzella
Bedside Ultrasonography for Arteriovenous Fistula Cannulation Roshan A. Patel, Aaron S. Stern, Maritza Brown, and Saad Bhatti Elmhurst Hospital, Icahn School of Medicine at Mount Sinai, Elmhurst, New York
ABSTRACT Difficulty in accessing a new arteriovenous fistula (AVF) is a common technical issue in hemodialysis patients, which often leads to interventional radiology and/or vascular surgery referral. As a consequence, the patient who needs dialysis may require a temporary dialysis catheter with its known potential complications. We present a case where bedside ultrasonography facilitated successful cannulation of a difficult AVF. Ultrasonogra-
phy (US) training in this procedure may allow early cannulation of new AVFs when the venous diameter is large enough (>0.6 cm) but the fistula is too deep (>0.6 cm). Real-time, US-guided AVF cannulation may also decrease the number of failed venous punctures per hemodialysis (HD) session minimizing vessel wall damage and subsequent potential hematoma and aneurysm formation.
Published KDOQI guidelines have established that the goals for permanent HD access placement in hemodialysis patients include a prevalent functional AVF placement rate of greater than 65% (1). A new primary fistula should be allowed to mature for at least 1 month, and ideally for 3–4 months, prior to cannulation. Difficulty in cannulating a new AVF is a common clinical problem, which often delays the use of the fistula and leads to longer duration of in situ tunneled dialysis catheters and their associated complications. When this occurs, the patient is referred to vascular surgery or interventional radiology for fistula evaluation. These services are not always readily available, which impedes patient care. We present a case of successful use of bedside US for cannulation of a new AVF that could not be accessed by dialysis nurse. Bedside US has been used successfully for gaining vascular access and is considered the standard of practice for central venous catheter placement.
Case A 77-year-old male with a past medical history of hypertension, diabetes mellitus type 2, and cerebrovascular accident was initiated on hemodialysis via a tunneled dialysis catheter. He had an AVF created shortly thereafter. Several months later the patient was admitted with fever, chills, and malaise. Blood cultures grew Stenotrophomonas maltophilia and the catheter was removed. HD via the AVF access was planned but the dialysis nursing staff had difficulty with cannulation. Interventional radiology (IR) was consulted and cannulation was performed under ultrasonography guidance. At the next dialysis session, the nursing staff once again had difficulty in cannulating the fistula. IR was unavailable to intervene but the patient needed urgent dialysis. A nephrologist trained in critical care with expertise in US utilized bedside US to successfully cannulate the AVF. The patient was dialyzed without complications and achieved adequate blood flows. US demonstrated that venous aspect of the AVF was more than 1 cm deep, explaining difficulty associated with cannulation. In a process analogous to US-guided central venous catheter or arterial line placement, bedside US allowed the deep vein of the AVF to be easily visualized and cannulated (Fig. 1A and B).
Address correspondence to: Roshan A. Patel, 7901 Broadway, C-7, Renal office, Elmhurst, New York 11373, Tel.: +7183343930, or e-mail: [email protected], [email protected] Conflict of interest: None. Seminars in Dialysis—Vol 28, No 4 (July–August) 2015 pp. 433–434 DOI: 10.1111/sdi.12394 © 2015 Wiley Periodicals, Inc. 433
434
Patel et al.
A
B
Fig. 1. (A) Ultrasound image before cannulation showing venous tract of AVF which is 1 cm deep. (B) Ultrasound image after cannulation with needle tip in vein without any hematoma.
Discussion Fistula maturation is defined as a process by which the vein becomes suitable for cannulation and performance of hemodialysis. Failure to do so is considered as primary failure. According to the current opinion-based clinical practice, characteristics of an optimal fistula include the following: (I) 6 mm in diameter with discernible margins when a tourniquet is in place, (II) less than 6 mm deep, (III) blood flow greater than 600 ml/minute, and (IV) maturation allowing successful cannulation approximately 6 weeks after surgical creation. When the vein is more than 6 mm deep, the limitation to its use is practical (difficulty in successfully cannulating) rather than physical (needles can readily reach the vein). Real time US guidance could address this problem. Ultrasound guidance has become the standard of practice for central venous cannulation (2,3,4). As an AVF is also a subcutaneous blood vessel, the same principles for cannulating a vein for catheter placement using real-time ultrasonography can be applied. US has been used for AVF evaluation including measuring blood flow, searching for thrombosis, and examining aneurysms but not for real-time fistula cannulation (5,6). US can also allow cannulation of AVF when the venous diameter is sufficient but the vessel is deep (>0.6 cm). Furthermore, real-time, US-guided AVF cannulation may decrease the number of failed venous punctures per HD session, which will reduce vessel wall damage and release of tissue thrombogenic factor and potentially decrease complications such as thrombosis, hematoma, and aneurysm formation. Early fistula cannulation can ultimately decrease the
duration of tunneled dialysis catheter use. A possible obstacle to successful use of US includes equipment costs. However, earlier and complication-free AVF use limits the costs to the unit for catheterrelated infection (antibiotics and missed treatments from hospitalizations) in addition to the costs to other payers for infections and AVF-related complications ($17,000 USD to $32,000 USD per hospital admission for catheter-related infections). In conclusion, ultrasound guidance is a potentially cost-effective approach for AVF cannulation of fistulas that are difficult to access. Early cannulation of a new fistula has the advantage of reducing the duration of the in situ tunneled dialysis catheters and their associated complications. Bedside US may also provide diagnostic information regarding fistula complications. We are currently conducting a prospective study examining the routine use of ultrasound guidance for new AVF cannulation to define its role in outpatient hemodialysis units. References 1. Vascular Access Work Group: Clinical practice guidelines for vascular access. Am J Kidney Dis 48:248–73, 2006 2. Jaques PF, Mauro MA, Keefe B: US guidance for vascular access. Technical note. J Vasc Interv Radiol 3(2):427–30, 1992 3. Troianos CA, Jobes DR, Ellison N: Ultrasound-guided cannulation of the internal jugular vein: a prospective, randomized study. Anesth Analg 72:823–6, 1991 4. Farrell GM M: Ultrasound-guided cannulation versus the landmarkguided technique for acute hemodialysis access. Nephrol Dial Transplant; 12(6):1234–7, 1997 5. Malovrh M: Strategy for the maximal use of native arteriovenous fistulae for hemodialysis. Sci World J 6:808–15, 2006 6. Davidson CD, Dolmatch B, Hasan M, Nichols D, Saxena R, Shenoy S, Vazquez M, Gallieni M: Duplex ultrasound evaluation for dialysis access selection and maintenance: a practical guide. J Vasc Access 9 (1):1–9, 2008
Bedside Ultrasonography for Arteriovenous Fistula Cannulation Roshan A. Patel, Aaron S. Stern, Maritza Brown, and Saad Bhatti Elmhurst Hospital, Icahn School of Medicine at Mount Sinai, Elmhurst, New York
ABSTRACT Difficulty in accessing a new arteriovenous fistula (AVF) is a common technical issue in hemodialysis patients, which often leads to interventional radiology and/or vascular surgery referral. As a consequence, the patient who needs dialysis may require a temporary dialysis catheter with its known potential complications. We present a case where bedside ultrasonography facilitated successful cannulation of a difficult AVF. Ultrasonogra-
phy (US) training in this procedure may allow early cannulation of new AVFs when the venous diameter is large enough (>0.6 cm) but the fistula is too deep (>0.6 cm). Real-time, US-guided AVF cannulation may also decrease the number of failed venous punctures per hemodialysis (HD) session minimizing vessel wall damage and subsequent potential hematoma and aneurysm formation.
Published KDOQI guidelines have established that the goals for permanent HD access placement in hemodialysis patients include a prevalent functional AVF placement rate of greater than 65% (1). A new primary fistula should be allowed to mature for at least 1 month, and ideally for 3–4 months, prior to cannulation. Difficulty in cannulating a new AVF is a common clinical problem, which often delays the use of the fistula and leads to longer duration of in situ tunneled dialysis catheters and their associated complications. When this occurs, the patient is referred to vascular surgery or interventional radiology for fistula evaluation. These services are not always readily available, which impedes patient care. We present a case of successful use of bedside US for cannulation of a new AVF that could not be accessed by dialysis nurse. Bedside US has been used successfully for gaining vascular access and is considered the standard of practice for central venous catheter placement.
Case A 77-year-old male with a past medical history of hypertension, diabetes mellitus type 2, and cerebrovascular accident was initiated on hemodialysis via a tunneled dialysis catheter. He had an AVF created shortly thereafter. Several months later the patient was admitted with fever, chills, and malaise. Blood cultures grew Stenotrophomonas maltophilia and the catheter was removed. HD via the AVF access was planned but the dialysis nursing staff had difficulty with cannulation. Interventional radiology (IR) was consulted and cannulation was performed under ultrasonography guidance. At the next dialysis session, the nursing staff once again had difficulty in cannulating the fistula. IR was unavailable to intervene but the patient needed urgent dialysis. A nephrologist trained in critical care with expertise in US utilized bedside US to successfully cannulate the AVF. The patient was dialyzed without complications and achieved adequate blood flows. US demonstrated that venous aspect of the AVF was more than 1 cm deep, explaining difficulty associated with cannulation. In a process analogous to US-guided central venous catheter or arterial line placement, bedside US allowed the deep vein of the AVF to be easily visualized and cannulated (Fig. 1A and B).
Address correspondence to: Roshan A. Patel, 7901 Broadway, C-7, Renal office, Elmhurst, New York 11373, Tel.: +7183343930, or e-mail: [email protected], [email protected] Conflict of interest: None. Seminars in Dialysis—Vol 28, No 4 (July–August) 2015 pp. 433–434 DOI: 10.1111/sdi.12394 © 2015 Wiley Periodicals, Inc. 433
434
Patel et al.
A
B
Fig. 1. (A) Ultrasound image before cannulation showing venous tract of AVF which is 1 cm deep. (B) Ultrasound image after cannulation with needle tip in vein without any hematoma.
Discussion Fistula maturation is defined as a process by which the vein becomes suitable for cannulation and performance of hemodialysis. Failure to do so is considered as primary failure. According to the current opinion-based clinical practice, characteristics of an optimal fistula include the following: (I) 6 mm in diameter with discernible margins when a tourniquet is in place, (II) less than 6 mm deep, (III) blood flow greater than 600 ml/minute, and (IV) maturation allowing successful cannulation approximately 6 weeks after surgical creation. When the vein is more than 6 mm deep, the limitation to its use is practical (difficulty in successfully cannulating) rather than physical (needles can readily reach the vein). Real time US guidance could address this problem. Ultrasound guidance has become the standard of practice for central venous cannulation (2,3,4). As an AVF is also a subcutaneous blood vessel, the same principles for cannulating a vein for catheter placement using real-time ultrasonography can be applied. US has been used for AVF evaluation including measuring blood flow, searching for thrombosis, and examining aneurysms but not for real-time fistula cannulation (5,6). US can also allow cannulation of AVF when the venous diameter is sufficient but the vessel is deep (>0.6 cm). Furthermore, real-time, US-guided AVF cannulation may decrease the number of failed venous punctures per HD session, which will reduce vessel wall damage and release of tissue thrombogenic factor and potentially decrease complications such as thrombosis, hematoma, and aneurysm formation. Early fistula cannulation can ultimately decrease the
duration of tunneled dialysis catheter use. A possible obstacle to successful use of US includes equipment costs. However, earlier and complication-free AVF use limits the costs to the unit for catheterrelated infection (antibiotics and missed treatments from hospitalizations) in addition to the costs to other payers for infections and AVF-related complications ($17,000 USD to $32,000 USD per hospital admission for catheter-related infections). In conclusion, ultrasound guidance is a potentially cost-effective approach for AVF cannulation of fistulas that are difficult to access. Early cannulation of a new fistula has the advantage of reducing the duration of the in situ tunneled dialysis catheters and their associated complications. Bedside US may also provide diagnostic information regarding fistula complications. We are currently conducting a prospective study examining the routine use of ultrasound guidance for new AVF cannulation to define its role in outpatient hemodialysis units. References 1. Vascular Access Work Group: Clinical practice guidelines for vascular access. Am J Kidney Dis 48:248–73, 2006 2. Jaques PF, Mauro MA, Keefe B: US guidance for vascular access. Technical note. J Vasc Interv Radiol 3(2):427–30, 1992 3. Troianos CA, Jobes DR, Ellison N: Ultrasound-guided cannulation of the internal jugular vein: a prospective, randomized study. Anesth Analg 72:823–6, 1991 4. Farrell GM M: Ultrasound-guided cannulation versus the landmarkguided technique for acute hemodialysis access. Nephrol Dial Transplant; 12(6):1234–7, 1997 5. Malovrh M: Strategy for the maximal use of native arteriovenous fistulae for hemodialysis. Sci World J 6:808–15, 2006 6. Davidson CD, Dolmatch B, Hasan M, Nichols D, Saxena R, Shenoy S, Vazquez M, Gallieni M: Duplex ultrasound evaluation for dialysis access selection and maintenance: a practical guide. J Vasc Access 9 (1):1–9, 2008
