1
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Sousa CN, Teles P, Ribeiro OMPL, Sousa R, Lira MN, Delgado E, Oliveira D, Campos L, Fernandes F, Moura SCM, Delgado MF, Sá TG, Teixeira SMP, Souza LH, Ribeiro RCHM, Oliveira GFN, Mendonça AEO, Ozen N. How to choose the appropriate cannulation technique for vascular access in hemodialysis patients. Ther Apher Dial 2023; 27:394-401. [PMID: 36717974 DOI: 10.1111/1744-9987.13973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 02/01/2023]
Abstract
The cannulation technique is important for the survival of the arteriovenous access. Choosing the appropriate technique is a complex decision. Such choice must be customized to patients, considering their characteristics, the type of arteriovenous access and the experience of the hemodialysis team. We describe seven items that can help nurses to identify the appropriate cannulation technique: type of arteriovenous access; drainage vein; hygienic self-care profile; experience of the nursing staff in the cannulation technique and nurse-to-patient ratio; hemodialysis treatment method; patient's condition; and patient's decision. Such items can help nurses in decision-making on the "ideal" cannulation technique for each patient.
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Affiliation(s)
- Clemente Neves Sousa
- S Francisco Dialysis Unit, Porto, Portugal.,CINTESIS-Center for Health Technology and Services Research Faculty of Medicine, Porto University, Porto, Portugal.,Nursing School of Porto, Porto, Portugal
| | - Paulo Teles
- School of Economics and LIAAD-INESC Porto LA, Porto University, Porto, Portugal
| | - Olga Maria Pimenta Lopes Ribeiro
- CINTESIS-Center for Health Technology and Services Research Faculty of Medicine, Porto University, Porto, Portugal.,Nursing School of Porto, Porto, Portugal
| | - Rui Sousa
- CINTESIS-Center for Health Technology and Services Research Faculty of Medicine, Porto University, Porto, Portugal
| | | | | | | | | | | | - Sandra Cristina Mendo Moura
- CINTESIS-Center for Health Technology and Services Research Faculty of Medicine, Porto University, Porto, Portugal.,Mogadouro Dialysis Unit-TECSAM; Unidade de Local Saúde Nordeste, Bragança, Portugal
| | - Millena Freire Delgado
- CINTESIS-Center for Health Technology and Services Research Faculty of Medicine, Porto University, Porto, Portugal
| | | | | | - Lara Helk Souza
- Medical School of São José do Rio Preto (FAMERP), São Paulo, Brazil
| | | | | | | | - Nurten Ozen
- Florence Nightingale Hospital School of Nursing, Demiroglu Bilim University, Istanbul, Turkey
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2
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Gelfand SL, Hentschel DM. Dialysis Access Considerations in Kidney Palliative Care. Semin Nephrol 2023; 43:151397. [PMID: 37579517 DOI: 10.1016/j.semnephrol.2023.151397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
In this review, we discuss common challenges at the interface between dialysis access planning, prognostication, and patient-centered decision making. Particularly for patients whose survival benefit from dialysis is attenuated by advanced age or other serious illness, knowing the potential complications and anticipated frequency of access procedures is essential for patients and families to be able to conceptualize what life on dialysis will look like. Although starting dialysis with a functioning graft or fistula is associated with reduced infection rates, mortality, hospitalizations, and cost compared with a central venous catheter, these benefits must be weighed against the chance that early access placement in an elderly or seriously ill patient is an unnecessary surgery because the chronic kidney disease never progresses, the patient dies before developing an indication to start dialysis, or, the patient prefers conservative kidney management over dialysis. Kidney palliative care is a growing subspecialty of nephrology focused on helping seriously ill patients navigate complex medical decisions, and may be useful for intensive goals-of-care discussions about treatment and access options for patients with limited anticipated survival because of age or other serious illness.
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Affiliation(s)
- Samantha L Gelfand
- Department of Medicine, Renal Division, Brigham and Women's Hospital, Boston MA; Department of Medicine, Division of Palliative Care, Brigham and Women's Hospital, Boston, MA; Department of Psychosocial Oncology and Palliative Care, Dana-Farber Cancer Institute, Boston, MA; Department of Medicine, Interventional Nephrology, Brigham and Women's Hospital, Boston, MA; Harvard Medical School, Boston, MA.
| | - Dirk M Hentschel
- Department of Medicine, Renal Division, Brigham and Women's Hospital, Boston MA; Department of Medicine, Interventional Nephrology, Brigham and Women's Hospital, Boston, MA; Harvard Medical School, Boston, MA
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3
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Mishra S, Mohanty S, Ramadoss A. Functionality of Flexible Pressure Sensors in Cardiovascular Health Monitoring: A Review. ACS Sens 2022; 7:2495-2520. [PMID: 36036627 DOI: 10.1021/acssensors.2c00942] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
As the highest percentage of global mortality is caused by several cardiovascular diseases (CVD), maintenance and monitoring of a healthy cardiovascular condition have become the primary concern of each and every individual. Simultaneously, recent progress and advances in wearable pressure sensor technology have provided many pathways to monitor and detect underlying cardiovascular illness in terms of irregularities in heart rate, blood pressure, and blood oxygen saturation. These pressure sensors can be comfortably attached onto human skin or can be implanted on the surface of vascular grafts for uninterrupted monitoring of arterial blood pressure. While the traditional monitoring systems are time-consuming, expensive, and not user-friendly, flexible sensor technology has emerged as a promising and dynamic practice to collect important health information at a comparatively low cost in a reliable and user-friendly way. This Review explores the importance and necessity of cardiovascular health monitoring while emphasizing the role of flexible pressure sensors in monitoring patients' health conditions to avoid adverse effects. A comprehensive discussion on the current research progress along with the real-time impact and accessibility of pressure sensors developed for cardiovascular health monitoring applications has been provided.
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Affiliation(s)
- Suvrajyoti Mishra
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
| | - Smita Mohanty
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
| | - Ananthakumar Ramadoss
- School for Advanced Research in Petrochemicals: Laboratory for Advanced Research in Polymeric Materials (LARPM), Central Institute of Petrochemicals Engineering and Technology (CIPET), Bhubaneswar-751024, India
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4
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Sánchez Tocino ML, López González A, Villoria González S, González Sánchez MI, García Macías M, González Horna A, Puente González AS, Handel Blanc M, Furaz Czereak K, Sánchez Tocino H. Validation of the inverse method for the determination of the access flow with thermodilution. Nefrologia 2022; 42:56-64. [PMID: 36153900 DOI: 10.1016/j.nefroe.2022.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 11/11/2020] [Accepted: 01/17/2021] [Indexed: 06/16/2023] Open
Abstract
INTRODUCTION Thermodiluction is a widely used method for measuring vascular access flow (QA). Among the possibilities of TD, the reverse method (MI) can be beneficial in the execution time, without impact on the dialysis efficacy (Kt). However, it is not a sufficiently studied technique. METHOD Transversal study of 117 arteriovenous fistulas (AVF). Two QA measurements were taken with the method described by the manufacturer (MR) and another with MI. MI is bases in the obtention of an inverted recirculation registry at the beginning of the session and a single subsequent recirculation measurement with the lines in normal position. In the concordance analysis, the Bland-Altman method and Cohen's Kappa index were used. RESULTS Very good concordance between MR and MI was evidenced for QA below 700 ml/min, but it worsens as flow increases. The median variability between the MR measurements (intra-method variability) was 3.4% (-17.13). This value did not differ from the median variability generated between MR and MI (inter-method variability), which was 2% (-14, 12) (P = 0.287). The degree of agreement between the two to identify AVFs susceptible to intervention was very good (K = 0.834). The time spent using the MI was significantly shorter (P = 0.000) without evidence of variations in the Kt of the measurement sessions (P = 0.201). CONCLUSIONS The thermodiluction MI is valid to determine the flow of the vascular access, especially in Qa lower than 700 ml/min, with great time savings, simplification of the procedure and without modifying the dialysis efficiency. The variability between the measurement by MR and MI is similar to that of MR. The concordance between methods in identifying potentially pathological AVFs is very good.
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5
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Astor BC, Hirschman K, Kennedy J, Frinak S, Besarab A. Development and validation of a risk score to prioritize patients for evaluation of access stenosis. Semin Dial 2021; 35:236-244. [PMID: 34642963 PMCID: PMC9292738 DOI: 10.1111/sdi.13026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/23/2021] [Indexed: 11/28/2022]
Abstract
Background Access flow dysfunction, often associated with stenosis, is a common problem in hemodialysis access and may result in progression to thrombosis. Timely identification of accesses in need of evaluation is critical to preserving a functioning access. We hypothesized that a risk score using measurements obtained from the Vasc‐Alert surveillance device could be used to predict subsequent interventions. Methods Measurement of five factors over the preceding 28 days from 1.46 million hemodialysis treatments (6163 patients) were used to develop a score associated with interventions over the subsequent 60 days. The score was validated in a separate dataset of 298,620 treatments (2641 patients). Results Interventions in arteriovenous fistulae (AVF; n = 4125) were much more common in those with the highest score (36.2%) than in those with the lowest score (11.0). The score also was strongly associated with interventions in patients with an arteriovenous graft (AVG; n = 2,038; 43.2% vs. 21.1%). There was excellent agreement in the Validation datasets for AVF (OR = 2.67 comparing the highest to lowest score) and good agreement for AVG (OR = 1.92). Conclusions This simple risk score based on surveillance data may be useful for prioritizing patients for physical examination and potentially early referral for intervention.
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Affiliation(s)
- Brad C Astor
- Department of Medicine, Division of Nephrology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, USA
| | | | | | - Stan Frinak
- Department of Internal Medicine, Henry Ford Hospital, Henry Ford Health System, Detroit, Michigan, USA
| | - Anatole Besarab
- Department of Medicine, Division of Nephrology, Stanford University School of Medicine, Stanford, California, USA
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6
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Preka E, Shroff R, Stronach L, Calder F, Stefanidis CJ. Update on the creation and maintenance of arteriovenous fistulas for haemodialysis in children. Pediatr Nephrol 2021; 36:1739-1749. [PMID: 33063165 DOI: 10.1007/s00467-020-04746-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 08/02/2020] [Accepted: 08/26/2020] [Indexed: 11/27/2022]
Abstract
Arteriovenous fistulas (AVFs) are widely used for haemodialysis (HD) in adults with stage 5 chronic kidney disease (CKD 5) and are generally considered the best form of vascular access (VA). The 'Fistula First' initiative in 2003 helped to change the culture of VA in adults. However, this cultural change has not yet been adopted in children despite the fact that a functioning AVF is associated with lower complication rates and longer access survival than a central venous line (CVL). For children with CKD 5, especially when kidney failure starts early in life, there is a risk that all VA options will be exhausted. Therefore, it is essential to develop long-term strategies for optimal VA creation and maintenance. Whilst AVFs are the preferred VA in the paediatric population on chronic HD, they may not be suitable for every child. Recent guidelines and observational data in the paediatric CKD 5 population recommend switching from a 'Catheter First' to 'Catheter Last' approach. In this review, recent evidence is summarized in order to promote change in current practices.
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Affiliation(s)
- Evgenia Preka
- Southampton Children's Hospital and University of Southampton School of Medicine, Tremona Road, Southampton, SO16 6YD, UK.
| | - Rukshana Shroff
- UCL Great Ormond Street Hospital for Children Institute of Child Health, London, UK
| | - Lynsey Stronach
- UCL Great Ormond Street Hospital for Children Institute of Child Health, London, UK
| | - Francis Calder
- UCL Great Ormond Street Hospital for Children Institute of Child Health, London, UK.,Evelina London Children's Hospital NHS Foundation Trust, London, UK
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7
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Sánchez Tocino ML, López González A, Villoria González S, González Sánchez MI, García Macías M, González Horna A, Puente González AS, Handel Blanc M, Furaz Czereak K, Sánchez Tocino H. Validation of the inverse method for the determination of the access flow with thermodilution. Nefrologia 2021; 42:S0211-6995(21)00089-8. [PMID: 34148666 DOI: 10.1016/j.nefro.2021.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 11/11/2020] [Accepted: 01/17/2021] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION Thermodilution is a widely used method for measuring vascular access flow (QA). Among the possibilities of thermodilution, the reverse method (RM) can be beneficial in the execution time, without impact on the dialysis efficacy (Kt). However, it is not a sufficiently studied technique. METHOD Transversal study of 117 arteriovenous fistulas. Two QA measurements were taken with the method described by the manufacturer (MR) and another with RM. RM is based on the obtention of an inverted recirculation registry at the beginning of the session and a single subsequent recirculation measurement with the lines in normal position. In the concordance analysis, the Bland-Altman method and Cohen's Kappa index were used. RESULTS Very good concordance between MR and RM was evidenced for QA below 700ml/min, but it worsens as flow increases. The median variability between the MR measurements (intra-method variability) was 3.4% (-17.13). This value did not differ from the median variability generated between MR and RM (inter-method variability), which was 2% (-14,12) (P=.287). The degree of agreement between the 2 to identify arteriovenous fistulas susceptible to intervention was very good (Kappa=0.834). The time spent using the RM was significantly shorter (P=.000) without evidence of variations in the Kt of the measurement sessions (P=.201). CONCLUSIONS The thermodilution RM is valid to determine the flow of the vascular access, especially in QA lower than 700ml/min, with great time savings, simplification of the procedure and without modifying the dialysis efficiency. The variability between the measurement by MR and RM is similar to that of MR. The concordance between methods in identifying potentially pathological arteriovenous fistulas is very good.
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8
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Ekart R, Varda L, Vodošek Hojs N, Dvoršak B, Piko N, Bevc S, Hojs R. Early Detection of Arteriovenous Fistula Stenosis in Hemodialysis Patients through Routine Measurements of Dialysis Dose (Kt/V). Blood Purif 2021; 51:15-22. [PMID: 33784665 DOI: 10.1159/000514939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 02/01/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Monitoring of arteriovenous (AV) fistula to detect hemodynamically important stenosis is crucial for the prevention of AV fistula thrombosis. The aim of our study was to analyze the importance of dialysis dose (Kt/V) during online postdilution hemodiafiltration (HDF) for early detection of AV fistula stenosis. METHODS Hemodialysis patients with AV fistula were included in this study. We compared a group of 44 patients who have undergone fistulography and subsequently percutaneous transluminal angioplasty (PTA) of significant AV fistula stenosis (active group) with a group of 44 age- and sex-matched patients without PTA (control group). Observational time in both groups was the same. RESULTS All patients had postdilution online HDF using a F5008 dialysis machine, which can measure online single-pool Kt/V. All data were analyzed during the performance of 2056 HDF procedures. In the active group, we found statistically significantly lower values of Kt/V, all 8 weeks before PTA. In the active group, there was a significant improvement in Kt/V in the first (p < 0.001) and second week (p = 0.049) after PTA. Three and 8 weeks after PTA, we did not find any statistically significant difference in Kt/V between both groups (p = 0.114; p = 0.058). Patients in the active group had statistically significantly lower substitution volumes and blood pump flow rates during HDF over the whole observation period before and after PTA. In contrast, there were no differences in venous pressure in the dialysis circuit between both groups throughout the observation period. CONCLUSION In hemodialysis patients with AV fistula, treated with online HDF, routine measurements of Kt/V during each HDF are a beneficial, quick, and straightforward method for early detection of hemodynamically significant AV fistula stenosis.
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Affiliation(s)
- Robert Ekart
- Department of Dialysis, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia.,Medical Faculty, University of Maribor, Maribor, Slovenia
| | - Luka Varda
- Medical Faculty, University of Maribor, Maribor, Slovenia
| | - Nina Vodošek Hojs
- Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia
| | - Benjamin Dvoršak
- Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia
| | - Nejc Piko
- Department of Dialysis, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia
| | - Sebastjan Bevc
- Medical Faculty, University of Maribor, Maribor, Slovenia.,Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia
| | - Radovan Hojs
- Medical Faculty, University of Maribor, Maribor, Slovenia.,Department of Nephrology, Clinic for Internal Medicine, University Medical Centre Maribor, Maribor, Slovenia
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Caro Acevedo P, Marchante R, Thuissard IJ, Sanz-Rosa D, Amann R, Hernandez B, Delgado R. A systematic follow-up protocol achieving a low hemodialysis graft thrombosis rate. J Vasc Access 2019; 20:683-690. [PMID: 31002279 DOI: 10.1177/1129729819838795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Graft is an alternative to native arteriovenous fistula to ensure permanent vascular access in hemodialysis patients. The most common complication is significant stenosis, which frequently causes thrombosis and graft loss. Periodic monitoring and surveillance with elective correction of stenotic lesions can prolong graft survival. OBJECTIVE To describe the effect of early diagnosis of significant stenosis on the rate of thrombosis and graft patency. METHODS Retrospective, observational study of a cohort of 86 prevalent patients undergoing hemodialysis with a graft as their vascular access. We applied a systematic follow-up protocol of 115 grafts based on various screening methods of monitoring (clinical monitoring, pre-pump arterial pressure, dynamic venous pressure, percentage of recirculation, and dose of dialysis) in conjunction with surveillance (normalized intra-access venous pressure and access flow). The annual rates of thrombosis, and primary, primary-assisted, and secondary patency were assessed. RESULTS The incidence of significant stenosis and thrombosis was 57.4% (65/115) and 39.0% (45/115), respectively. Of all screening procedures, normalized intra-access venous pressure was the best predictor of significant stenosis (hazards ratio, 7.71; 95% confidence interval, 3.06-19.46). The annual rate of thrombosis fluctuated from 0 to 0.26 thromboses/patient/year, with an average rate of 0.14 thromboses/patient/year. Primary, primary-assisted, and secondary patency were 74%/79%/82%, 50%/60%/66%, and 23%/35%/37% at 1, 2, and 5 years, respectively. CONCLUSION The implementation of a systematic graft follow-up protocol combined with monitoring and surveillance enabled early diagnosis and elective correction of significant stenosis, prolonged graft patency, and a low thrombosis rate.
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Affiliation(s)
| | - Rosa Marchante
- Department of Nephrology, Hospital Ruber Juan Bravo, Madrid, Spain
| | - Israel J Thuissard
- School of Doctoral Studies and Research, Universidad Europea, Madrid, Spain
| | - David Sanz-Rosa
- School of Doctoral Studies and Research, Universidad Europea, Madrid, Spain
| | - Raquel Amann
- Department of Nephrology, Hospital Ruber Juan Bravo, Madrid, Spain
| | | | - Ramón Delgado
- Department of Nephrology, Hospital Ruber Juan Bravo, Madrid, Spain
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10
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Spanish Clinical Guidelines on Vascular Access for Haemodialysis. Nefrologia 2018; 37 Suppl 1:1-191. [PMID: 29248052 DOI: 10.1016/j.nefro.2017.11.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 06/21/2017] [Indexed: 12/26/2022] Open
Abstract
Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.
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11
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Hwang SD, Lee JH, Lee SW, Kim JK, Kim MJ, Song JH. Comparison of ultrasound scan blood flow measurement versus other forms of surveillance in the thrombosis rate of hemodialysis access: A systemic review and meta-analysis. Medicine (Baltimore) 2018; 97:e11194. [PMID: 30045249 PMCID: PMC6078674 DOI: 10.1097/md.0000000000011194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The benefit of access flow surveillance in preventing vascular access thrombosis and failure remains controversial, as many randomized clinical trials (RCTs) have failed to demonstrate consistent results. The aim of this study was to perform a meta-analysis including newly published RCTs with a subgroup analysis for arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs). METHODS A systematic review of the available literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. An electronic search was conducted using the MEDLINE, EMBASE, and Cochrane Library databases of RCTs conducted from 1970 to 2017 that involved access flow surveillance. As a result, 9 RCTs met our criteria. The control group was defined by indirect and various surveillance methods such as dynamic venous pressure measurement and physical examination. Conversely, the interventional group was defined as a noninvasive duplex ultrasound scan (USS) or ultrasound dilution that directly measured the flow of vascular access. RESULTS The studies included 990 patients comprising 658 native AVFs and 332 AVGs. The prevalence of diabetes was 29.3%and 30.5% in the interventional and control groups, respectively. The estimated overall pooled risk ratio (RR) of thrombosis was 0.782 [95% confidence interval (95% CI), 0.553-1.107; P = .17], favoring interventional group, although this was not statistically significant. In the subgroup analysis, the pooled RR of thrombosis was .562 (95% CI, 0.346-0.915; P = .02) for AVFs, which significantly favored the interventional group. Conversely, the pooled RR for AVGs was 1.104 (95% CI, 0.672-1.816; P = .70). CONCLUSION The surveillance method to measure access flow through USS showed a significant benefit for reducing thrombosis in AVFs. The result encourages adherence to the current guidelines for AVFs. However, no benefit was found regarding AVGs. Recent guidelines with a "one-size-fits-all" approach may be revised to a "tailored-to-risk" approach.
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Affiliation(s)
- Seun Deuk Hwang
- Division of Nephrology and Hypertension, Department of Internal Medicine, Inha University School of Medicine, Incheon
| | - Jin Ho Lee
- Division of Nephrology, Department of Internal Medicine, Bongseng-Memorial Hospital, Busan, Korea
| | - Seoung Woo Lee
- Division of Nephrology and Hypertension, Department of Internal Medicine, Inha University School of Medicine, Incheon
| | - Joong kyung Kim
- Division of Nephrology, Department of Internal Medicine, Bongseng-Memorial Hospital, Busan, Korea
| | - Moon-Jae Kim
- Division of Nephrology and Hypertension, Department of Internal Medicine, Inha University School of Medicine, Incheon
| | - Joon Ho Song
- Division of Nephrology and Hypertension, Department of Internal Medicine, Inha University School of Medicine, Incheon
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12
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Adding access blood flow surveillance reduces thrombosis and improves arteriovenous fistula patency: a randomized controlled trial. J Vasc Access 2017; 18:352-358. [DOI: 10.5301/jva.5000700] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2017] [Indexed: 02/03/2023] Open
Abstract
Purpose Stenosis is the main cause of arteriovenous fistula (AVF) failure. It is still unclear whether surveillance based on vascular access blood flow (QA) enhances AVF function and longevity. Methods We conducted a three-year follow-up randomized, controlled, multicenter, open-label trial to compare QA-based surveillance and pre-emptive repair of subclinical stenosis with standard monitoring/surveillance techniques in prevalent mature AVFs. AVFs were randomized to either the control group (surveillance based on classic alarm criteria; n = 104) or to the QA group (QA measured quarterly using Doppler ultrasound [ M-Turbo®] and ultrasound dilution [Transonic®] added to classic surveillance; n = 103). The criteria for intervention in the QA group were: 25% reduction in QA, QA<500 mL/min or significant stenosis with hemodynamic repercussion (peak systolic velocity [PSV] more than 400 cm/sc or PSV pre-stenosis/stenosis higher than 3). Results At the end of follow-up we observed a significant reduction in the thrombosis rate in the QA group (0.025 thrombosis/patient/year in the QA group vs. 0.086 thrombosis/patient/year in the control group [p = 0.007]). There was a significant improvement in the thrombosis-free patency rate (HR, 0.30; 95% CI, 0.11-0.82; p = 0.011) and in the secondary patency rate in the QA group (HR, 0.49; 95% CI, 0.26-0.93; p = 0.030), with no differences in the primary patency rate between the groups (HR, 0.98; 95% CI, 0.57-1.61; p = 0.935). There was greater need for a central venous catheter and more hospitalizations associated with vascular access in the control group (p = 0.034/p = 0.029). Total vascular access-related costs were higher in the control group (€227.194 vs. €133.807; p = 0.029). Conclusions QA-based surveillance combining Doppler ultrasound and ultrasound dilution reduces the frequency of thrombosis, is cost effective, and improves thrombosis free and secondary patency in autologous AVF.
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13
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Martínez Carnovale L, Esteve Simó V, Yeste Campos M, Artigas Raventós V, Llagostera Pujol S. Utilidad del mapeo ecográfico preoperatorio para los accesos vasculares de hemodiálisis. ANGIOLOGIA 2016. [DOI: 10.1016/j.angio.2016.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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The Impact of Access Blood Flow Surveillance on Reduction of Thrombosis in Native Arteriovenous Fistula: A Randomized Clinical Trial. J Vasc Access 2015; 17:13-9. [DOI: 10.5301/jva.5000461] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2015] [Indexed: 12/22/2022] Open
Abstract
Purpose The usefulness of access blood flow (QA) measurement is an ongoing controversy. Although all vascular access (VA) clinical guidelines recommend monitoring and surveillance protocols to prevent VA thrombosis, randomized clinical trials (RCTs) have failed to consistently show the benefits of QA-based surveillance protocols. We present a 3-year follow-up multicenter, prospective, open-label, controlled RCT, to evaluate the usefulness of QA measurement using Doppler ultrasound (DU) and ultrasound dilution method (UDM), in a prevalent hemodialysis population with native arteriovenous fistula (AVF). Methods Classical monitoring and surveillance methods are applied in all patients, the control group (n = 98) and the QA group (n = 98). Besides this, DU and UDM are performed in the QA group every three months. When QA is under 500 ml/min or there is a >25% decrease in QA the patient goes for fistulography, surgery or close clinical/surveillance observation. Thrombosis rate, assisted primary patency rate, primary patency rate and secondary patency rate are measured. Results After one-year follow-up we found a significant reduction in thrombosis rate (0.022 thrombosis/patient/year at risk in the QA group compared to 0.099 thrombosis/patient/year at risk in the control group [p = 0.030]). Assisted primary patency rate was significantly higher in the QA group than in control AVF (hazard ratio [HR] 0.23, 95% confidence interval [CI] 0.05-0.99; p = 0.030). In the QA group, the numbers unddergoing angioplasty and surgery were higher but with no significant difference in non-assisted primary patency rate (HR 1.41, 95% CI 0.72-2.84; p = 0.293). There was a non-significant improvement in secondary patency rate in the QA group (HR 0.510, 95% CI 0.17-1.50; p = 0.207). Conclusions The measurement of QA combining DU and UDM shows a reduction in thrombosis rate and an increased assisted primary patency rate in AVF after one-year follow-up. Trial registration ClinicalTrials.gov Identifier: NCT02111655.
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Muchayi T, Salman L, Tamariz LJ, Asif A, Rizvi A, Lenz O, Vazquez-Padron RI, Tabbara M, Contreras G. A meta-analysis of randomized clinical trials assessing hemodialysis access thrombosis based on access flow monitoring: where do we stand? Semin Dial 2015; 28:E23-9. [PMID: 25644548 DOI: 10.1111/sdi.12342] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommends the routine use of hemodialysis arteriovenous (AV) access surveillance to detect hemodynamically significant stenoses and appropriately correct them to reduce the incidence of thrombosis and to improve accesses patency rates. Access blood flow monitoring is considered as one of the preferred surveillance method for both AV fistulas (AVF) and AV grafts (AVG); however, published studies have reported conflicting results of its utility that led healthcare professionals to doubt the benefits of this surveillance method. We performed a meta-analysis of the published randomized controlled trials (RCTs) of AV access surveillance using access blood flow monitoring. Our hypothesis was that access blood flow monitoring lowers the risk of AV access thrombosis and that the outcome differs between AVF and AVG. The estimated overall pooled risk ratio (RR) of thrombosis was 0.87 (95% confidence interval [CI], 0.67-1.13) favoring access blood flow monitoring. The pooled RR of thrombosis were 0.64 (95% CI, 0.41-1.01) and 1.06 (95% CI, 0.77-1.46) in the subgroups of only AVF and only AVG, respectively. Our results added to the uncertainty of access blood flow monitoring as a surveillance method of hemodialysis accesses.
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Kraemer M. Physiological monitoring and control in hemodialysis: state of the art and outlook. Expert Rev Med Devices 2014; 3:617-34. [PMID: 17064247 DOI: 10.1586/17434440.3.5.617] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Medical devices for monitoring and feedback control of physiological parameters of the dialysis patient were introduced in the early 1990s. They have a wide range of applications, aiming at increasing the safety and ensuring the efficiency of the treatment, and at an improved restoration of physiological conditions, leading to an overall reduction in morbidity and mortality. Such devices include sensors for the measurement of temperature, optical parameters and sound speed in blood, and electrical characteristics of the human body, and other parameters. Essential for the development of these devices is a detailed understanding of the pathophysiological background of a therapeutical problem. There is still a large potential to introduce new devices for further therapy improvement and automation. Also, the size of the hemodialysis market appears attractive; however, a new product has to meet several specific requirements in order to also become commercially successful. This review describes the therapeutic and technical principles of several available devices, reports on concepts for possible future devices, and presents a short overview on the market environment.
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Affiliation(s)
- Matthias Kraemer
- Fresenius Biotech GmbH, Borkenberg 14, 61440 Oberursel, Germany.
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Vascular access for hemodialysis: postoperative evaluation and function monitoring. Int Urol Nephrol 2013; 46:403-9. [PMID: 24046176 DOI: 10.1007/s11255-013-0564-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 09/06/2013] [Indexed: 10/26/2022]
Abstract
Vascular access (VA) survival is a crucial issue associated with morbidity and mortality of patients undergoing maintenance hemodialysis. The development of stenosis is the major factor that leads to VA failure. Strategies for early detection of lesions within a VA system before serious complications arise are therefore crucial. The implementation of a VA surveillance program could lead to timely detection of VA dysfunction and referral for correction, reduction in central venous catheter use and decrease in hospitalization and VA-related cost. Suggested methods for arteriovenous fistulae and grafts surveillance include blood flow measurement, static pressure evaluation and duplex ultrasonography. Physical examination is an accepted method in contrast to nonstandardized dynamic pressure measurement for grafts. Access recirculation (not urea based) and dynamic pressure measurements are accepted methods for fistulae. Decreasing URR or Kt/V (otherwise unexplained) and increased (negative) arterial pressure in the dialysis machine are methods of limited sensitivity and specificity for both fistulae and grafts. Measurement of access blood flow has been proposed as the gold standard for the screening of all types of VA. Access flow can be measured by various techniques which are direct or indirect. Several studies about VA surveillance programs have demonstrated conflicting results. Larger, randomized controlled trials need to be carried out in order to clarify whether surveillance programs are necessary and which is the best surveillance strategy for each type of VA.
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Park HS, Kang SH, Chung BH, Choi BS, Park CW, Yang CW, Kim YS. Effect of intradialytic change in blood pressure and ultrafiltration volume on the variation in access flow measured by ultrasound dilution. Kidney Res Clin Pract 2013; 32:16-20. [PMID: 26889432 PMCID: PMC4716113 DOI: 10.1016/j.krcp.2012.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 09/29/2012] [Accepted: 10/09/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Prospective access flow measurement is the preferred method for vascular access surveillance in hemodialysis (HD) patients. We studied the effect of intradialytic change in blood pressure and ultrafiltration volume on the variation in access flow measured by ultrasound dilution. METHODS Access flow was measured 30 minutes, 120 minutes, and 240 minutes after the start of HD by ultrasound dilution in 30 patients during 89 HD sessions and evaluated for variation. RESULTS The mean age of the 30 patients was 62±11 years: 19 were male. The accesses comprised 16 fistulae and 14 grafts. The mean access flow over all sessions decreased by 6.1% over time (1265±568 mL/min after 30 minutes, 1260±599 mL/min after 120 minutes, and 1197±576 mL/min after 240 minutes, P<0.01 by repeated measures ANOVA). In addition, a≥5% decrease in mean arterial pressure during HD significantly reduced access flow (P=0.014). However, no other variable (ultrafiltration volume, sex, age, presence of diabetes, type or location of access, body surface area, hemoglobin, serum albumin level) interacted significantly with the effect of time on access flow. Furthermore, mean arterial pressure did not correlate with ultrafiltration volume. CONCLUSION We conclude that the variation in access flow during HD is relatively small. Decreased blood pressure is a risk factor for variation in access flow measured by ultrasound dilution. In most patients whose blood pressures are stable during HD, the access flow can be measured at any time during the HD treatment.
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Affiliation(s)
- Hoon Suk Park
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Seok Hui Kang
- Department of Internal Medicine, Yeungnam University Hospital, Daegu, Korea
| | - Byung Ha Chung
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Bum Soon Choi
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Cheol Whee Park
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Chul Woo Yang
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Yong-Soo Kim
- Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
- Corresponding author. Department of Internal Medicine, The Catholic University of Korea College of Medicine, 505 Banpo-dong, Seocho-gu, Seoul, 137-040, Korea.
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Abstract
A mature, functional arteriovenous (AV) access is the lifeline for a hemodialysis (HD) patient as it provides sufficient enough blood flow for adequate dialysis. As the chronic kidney disease (CKD) and end-stage renal disease (ESRD) population is expanding, and because of the well-recognized hazardous complications of dialysis catheters, the projected placement and use of AV accesses for HD is on the rise. Although a superior access than catheters, AV accesses are not without complications. The primary complication that causes AV accesses to fail is stenosis with subsequent thrombosis. Surveying for stenosis can be performed in a variety of ways. Clinical monitoring, measuring flow, determining pressure, and measuring recirculation are all methods that show promise. In addition, stenosis can be directly visualized, through noninvasive techniques such as color duplex imaging, or through minimally invasive venography. Each method of screening has its advantages and disadvantages, and several studies exist which attempt to answer the question of which test is the most useful. Ultimately, to maintain the functionality of the access for the HD patient, a team approach becomes imperative. The collaboration and cooperation of the patient, nephrologist, dialysis nurse and technician, vascular access coordinator, interventionalist, and vascular surgeon is necessary to preserve this lifeline.
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Affiliation(s)
- William L Whittier
- Department of Internal Medicine, Division of Nephrology, Rush University Medical Center, Chicago, Illinois
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Abstract
The Centers for Medicare and Medicaid Services (CMS) recently revised the requirements that end-stage renal disease (ESRD) dialysis facilities must meet to be certified under Medicare. The CMS ESRD Interpretive Guidance Update states that the dialysis facility must now have an ongoing program of hemodialysis vascular access surveillance. Surveillance usually refers to monthly access blood flow or static dialysis venous pressure measurements combined with preemptive correction of stenosis. However, surveillance as currently practiced does not accurately predict synthetic graft thrombosis or prolong graft life. There is limited evidence that monthly surveillance may reduce native arteriovenous fistula thrombosis without prolonging fistula life, but the effect on thrombosis awaits further confirmation. Thus, the CMS surveillance requirement is not evidence based. We recommend the following changes to the ESRD Interpretive Guidance Update: only monitoring (e.g., physical examination) is required, whereas the proper role of surveillance awaits the results of further research. Such changes would allow nephrologists to apply the clinical judgment and individualized care that is most beneficial to their patients.
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Hollenbeck M, Mickley V, Brunkwall J, Daum H, Haage P, Ranft J, Schindler R, Thon P, Vorwerk D. Gefäßzugang zur Hämodialyse. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11560-009-0281-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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The Society for Vascular Surgery: Clinical practice guidelines for the surgical placement and maintenance of arteriovenous hemodialysis access. J Vasc Surg 2008; 48:2S-25S. [DOI: 10.1016/j.jvs.2008.08.042] [Citation(s) in RCA: 385] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 08/15/2008] [Accepted: 08/18/2008] [Indexed: 11/20/2022]
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Ram SJ, Nassar R, Work J, Abreo K, Dossabhoy NR, Paulson WD. Risk of Hemodialysis Graft Thrombosis: Analysis of Monthly Flow Surveillance. Am J Kidney Dis 2008; 52:930-8. [DOI: 10.1053/j.ajkd.2008.07.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Accepted: 07/22/2008] [Indexed: 11/11/2022]
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Wijnen E, van der Sande FM, Tordoir JHM, Kooman JP, Leunissen KML. Effect of online haemodialysis vascular access flow evaluation and pre-emptive intervention on the frequency of access thrombosis. Clin Kidney J 2008; 1:279-84. [PMID: 25983912 PMCID: PMC4421281 DOI: 10.1093/ndtplus/sfn136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2007] [Accepted: 08/01/2008] [Indexed: 11/17/2022] Open
Abstract
Introduction. Guidelines advocate surveillance of vascular access to reduce incidences of thrombosis. However, the value of online vascular access flow monitoring is still under debate. Methods. Through a systematic literature search, the effect of online access flow surveillance combined with pre-emptive intervention on thrombosis frequency is reviewed. Results. Due to methodological differences, adequate comparison of the individual study results is not possible. Moreover, the methodological quality of most of the included studies is not suitable for an adequate statistical analysis of the results. Conclusion. Until now, there is no conclusive evidence that online access flow evaluation has a significant effect on the rate of thrombosis. Future large-scale studies with adequate study design, adequate surveillance and intervention protocols and, possibly, better pre-emptive intervention alternative(s) are necessary.
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Affiliation(s)
- Edwin Wijnen
- Department of Internal Medicine, Division of Nephrology
| | | | - Jan H M Tordoir
- Department of Surgery , University Hospital Maastricht , Maastricht , The Netherlands
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Paulson WD, Ram SJ, Work J, Conrad SA, Jones SA. Inflow stenosis obscures recognition of outflow stenosis by dialysis venous pressure: analysis by a mathematical model. Nephrol Dial Transplant 2008; 23:3966-71. [DOI: 10.1093/ndt/gfn400] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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A novel simple hemoglobin dilution technique to measure hemodialysis vascular access flow. Kidney Int 2008; 73:1082-6. [DOI: 10.1038/ki.2008.10] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Soman S, Zasuwa G, Yee J. Automation, decision support, and expert systems in nephrology. Adv Chronic Kidney Dis 2008; 15:42-55. [PMID: 18155109 DOI: 10.1053/j.ackd.2007.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Increasing data suggest that errors in medicine occur frequently and result in substantial harm to the patient. The Institute of Medicine report described the magnitude of the problem, and public interest in this issue, which was already large, has grown. The traditional approach in medicine has been to identify the persons making the errors and recommend corrective strategies. However, it has become increasingly clear that it is more productive to focus on the systems and processes through which care is provided. If these systems are set up in ways that would both make errors less likely and identify those that do occur and, at the same time, improve efficiency, then safety and productivity would be substantially improved. Clinical decision support systems (CDSSs) are active knowledge systems that use 2 or more items of patient data to generate case specific recommendations. CDSSs are typically designed to integrate a medical knowledge base, patient data, and an inference engine to generate case specific advice. This article describes how automation, templating, and CDSS improve efficiency, patient care, and safety by reducing the frequency and consequences of medical errors in nephrology. We discuss practical applications of these in 3 settings: a computerized anemia-management program (CAMP, Henry Ford Health System, Detroit, MI), vascular access surveillance systems, and monthly capitation notes in the hemodialysis unit.
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White JJ, Jones SA, Ram SJ, Schwab SJ, Paulson WD. Mathematical model demonstrates influence of luminal diameters on venous pressure surveillance. Clin J Am Soc Nephrol 2007; 2:681-7. [PMID: 17699482 DOI: 10.2215/cjn.01070307] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND The reliability of dialysis venous pressure (VP) in detecting stenosis is controversial. A mathematical model may help to resolve the controversy by providing insight into the factors that influence static VP. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS This study used inflow artery and outflow vein luminal diameters from duplex ultrasound studies of 94 patients. These diameters were applied to a mathematical model, and how they affect the relation among VP, mean arterial pressure (MAP), blood flow, and stenosis was determined. Whether VP/MAP is a valid adjustment for the influence of MAP on VP, and whether the standard VP/MAP referral threshold of 0.50 is valid, were also determined. RESULTS It was found that there is an approximate one-to-one relation between MAP and VP, so VP/MAP is a valid adjustment. Also, the 0.50 threshold successfully identifies most grafts with stenosis of 65% or more. However, the ratio of artery/vein diameters varied widely between patients, and the ratio independently influences VP/MAP. When the inflow artery is relatively narrow, the VP/MAP increase is delayed followed by a more rapid increase as critical stenosis is reached. CONCLUSIONS VP/MAP is a valid adjustment for the influence of MAP on VP, and the standard VP/MAP threshold of 0.50 warns of the transition to critical stenosis. However, relatively narrow arteries cause a delay followed by a rapid increase in VP/MAP that may not be detected before thrombosis unless measurements are very frequent. Clinical trials that emphasize trend analysis with frequent measurements are needed to evaluate the efficacy of VP surveillance.
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Affiliation(s)
- John J White
- Augusta VA Medical Center, and Section of Nephrology, Hypertension, and Renal Transplantation, Medical College of Georgia, Augusta, Georgia 30912, USA
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Ross J. Pro/Con Prophylactic AV Graft Angioplasty: Worth Doing?: Data Shows it has Value. J Vasc Access 2006. [DOI: 10.1177/112972980600700431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- J. Ross
- University of California Davis Medical Center, Sacramento, CA - USA
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