Quantification of the severity of outflow stenosis of hemodialysis fistulas with a pulse- and thrill-based scoring system

The knowledge, attitudes, and practices of arteriovenous access assessment among hemodialysis nurses: A multicenter cross-sectional survey

INTRODUCTION

Hemodialysis nurses' cannulation technique, monitoring, and management methods can affect patients' vascular access longevity. An arteriovenous access assessment comprises a medical history and vascular assessment through physical examination and surveillance. However, further exploration is needed to fully understand hemodialysis nurses' knowledge, attitudes, and practices (KAP) in this area.

METHODS

Between June and July 2023, we recruited hemodialysis nurses from 21 cities in Guangdong Province using a convenience sampling method. Four questionnaires-the General Data Questionnaire, the KAP Scale of Arteriovenous Access Assessment among Hemodialysis Nurses, the Utrecht Work Engagement Scale, and the NASA Task Load Index-were utilized for data collection through the Questionnaire Star platform.

FINDINGS

Of the 530 hemodialysis nurses participating in the study, 458 (86.4%) had a valid response. The participants demonstrated moderate knowledge and practice levels regarding arteriovenous access assessment and exhibited positive attitudes. We identified several factors related to arteriovenous access assessment that predict KAP in hemodialysis nurses. These factors included years of experience as a hemodialysis nurse, whether a nurse's knowledge of physical examination was sufficient to meet clinical needs, whether a nurse had received training in performing physical examination, whether a nurse's department regularly checked the quality of physical examination, and nurses' levels of work engagement and mental workload. All factors explained 32.4% of the variance in participants' KAP regarding arteriovenous access assessment.

DISCUSSION

Improving hemodialysis nurses' assessment of arteriovenous access is crucial to ensure optimal patient care. Dialysis center managers and educators should prioritize understanding hemodialysis nurses' KAP of arteriovenous access assessment and any factors influencing these areas.

Quantitative physical examination indicators to detect patients with stenosis at a high risk of thrombosis at hemodialysis vascular access sites: A retrospective case-control study

BACKGROUND

Quantitative physical examination (PE) indicators, including palpable pulsatility length and outflow scores, can be used to quantify stenosis severity at hemodialysis vascular access sites. It is known that the risk of high-shear-related thrombosis is increased when the minimal luminal diameter (MLD) of stenosis decreases. At present, MLD is measured using sonography or angiography. This study sought to determine the relationship between quantitative PE indicators and MLD and report their diagnostic performance in detecting patients with stenosis at a high risk of thrombosis.

METHODS

We performed a retrospective case-control study using routinely collected data. We used the post-stenosis palpable pulsatility length (sPPL) and pulse-and-thrill based outflow score to assess the severity of AVF inflow and outflow stenosis, respectively. We recorded paired quantitative PE indicators and MLD before and after angioplasty in patients enrolled over a 4-month period.

RESULTS

A total of 249 paired PE indicators and MLD measurements were obtained from 163 patients. A receiver operating characteristic curve analysis showed that an MLD cutoff value of <1.55 mm and an MLD of <1.95 mm discriminated sPPL = 0 and PESOS (physical examination significant outflow stenosis)/1- of the outflow score, respectively, from all other measurements, with the area under the curve values of 0.8922 and 0.9618, respectively. With sPPL = 0 and PESOS/1- of the outflow score as diagnostic tools to detect inflow stenosis with an MLD of ⩽1.5 mm and outflow stenosis with an MLD of ⩽1.9 mm at vascular access sites, sensitivity = 86.00% and 88.46%; specificity = 97.67% and 92.11%; positive predictive values of 97.73% and 92.00% and negative predictive values of 85.71% and 88.61%, respectively, were observed.

CONCLUSIONS

Our preliminary results showed that physical examination can potentially be a diagnostic tool in detecting patients with stenosis who are at a high risk of thrombosis at hemodialysis vascular access sites with high diagnostic accuracy.

Characterization of hemodialysis fistulas experienced abrupt thrombosis and determination of a proper follow-up protocol: A retrospective cohort study and an interventionist's perspective

Abrupt thrombosis is a form of thrombosis that occurs unexpectedly and without being preceded by hemodialysis fistula (AVF) dysfunction during dialysis. We found that AVFs with a history of abrupt thrombosis (abtAVF) appeared to have more episodes of thrombosis and required more frequent interventions than those without such history. Therefore, we sought to characterize the abtAVFs and examined our follow-up protocols to determine which one is optimal. We performed a retrospective cohort study using routinely collected data. The thrombosis rate, AVF loss rate, thrombosis-free primary patency, and secondary patency were calculated. Additionally, the restenosis rates of the AVFs under the follow-up protocol/sub-protocols and the abtAVFs were determined. The thrombosis rate, procedure rate, AVF loss rate, thrombosis-free primary patency, and secondary patency of the abtAVFs were 0.237/pt-yr, 2.702/pt-yr, 0.027/pt-yr, 78.3%, and 96.0%, respectively. The restenosis rate for AVFs in the abtAVF group and the angiographic follow-up sub-protocol were similar. However, the abtAVF group had a significantly higher thrombosis rate and AVF loss rate than AVFs without a history of abrupt thrombosis (n-abtAVF). The lowest thrombosis rate was observed for n-abtAVFs, followed up periodically under the outpatient or angiographic sub-protocols. AVFs with a history of abrupt thrombosis had a high restenosis rate, and periodic angiographic follow-up with a mean interval of 3 months was presumed appropriate. For selected populations, such as salvage-challenging AVFs, periodic outpatient or angiographic follow-up was mandatory to extend their usable lives for hemodialysis.

An eighth note

Venous stenosis is the most common cause of arteriovenous fistula (AVF) failure in hemodialysis patients. For patients with AVF stenosis, the pressure over the antecedent part of the AVF stenotic lesion will increase if arterial inflow is sufficient. We report a chronic hemodialysis patient who received an angiographic examination for the juxta-anastomosis stenosis of his AVF. A unique feature of a collateral venous branch antecedent to the stenotic lesion was noted, resembling a musical sign as the "eighth note." After percutaneous transluminal angioplasty, the eighth note attenuated markedly at once. Of note, the eighth note sign is not seen frequently, and thus we postulate that the formation of an eighth note sign on the radiocephalic fistula should fulfill the following requirements, including a sufficient arterial inflow, an adjacent collateral branch close enough to the arteriovenous anastomosis, a severe juxta-anastomotic stenotic lesion, and an intact ulnar venous drainage system.