Digital Brachial Index Research Articles

Hand Acceleration Time is a Valuable Ultrasonographic Tool in Hand Perfusion as Adjuvant Evaluation for Diagnosing Chronic Upper Limb Ischemia

Diagnosis of chronic upper limb ischemia is mainly clinical. Although hand perfusion can be evaluated by different noninvasive methods (e.g., digital-brachial index, digital pressures, oxygen saturation measurements, and plethysmography), these have not been standardized for the diagnosis of chronic upper limb ischemia. Initial reports suggested that the hand acceleration time (HAT) measured by duplex ultrasound could be a useful diagnostic tool. However, the HAT has neither been properly characterized nor validated. This study aimed to provide evidence that HAT is a sensitive diagnostic tool for chronic upper limb ischemia. We conducted a prospective, single-center, cross-sectional study with adult patients diagnosed with chronic upper limb ischemia and healthy adult volunteers without cardiovascular risk factors. Hand vascular duplex ultrasound and HAT measurement were performed in 4 artery locations: princeps pollicis artery, radialis indicis artery, first common digital palmar artery, and third common digital palmar artery. It was also measured in the ulnar and radial arteries. Descriptive and exploratory analyses were performed between patients and healthy volunteers. Thirty participants were included, being 15 patients (median [standard deviation] age: 51 [18] years; 47% women) and 15 healthy volunteers (median [standard deviation] age: 35 [10] years; 60% women). In total, 15 ischemic and 30 nonischemic hands were analyzed. Humeral artery stenosis/occlusion (n=6, 40.0%) and distal artery stenosis (n=5, 33.3%) were the main causes of ischemia. Median (interquartile range) HAT measurements were significantly different between patients and healthy volunteers in the 4 hand arterial locations, the radial artery, and ulnar artery: princeps pollicis artery: 164 (124-252) vs. 60 (40-88), P<0.001; radialis indicis artery: 176 (140-348) vs. 60 (36-80), P<0.001; first common digital palmar artery: 180 (92-320) vs. 64 (36-88), P<0.001; third common digital palmar artery: 180 (104-240) vs. 56 (44-92), P<0.001; radial artery: 156 (120-248) vs. 68 (55-76), P<0.001; and ulnar artery: 152 (76-220) vs. 61 (48-76), P<0.001. Vascular duplex ultrasound with HAT measurement seems to be an easy-access, sensitive diagnostic tool for chronic upper limb ischemia. HAT provides valuable information on hand perfusion and may be complementary to current noninvasive methods.

Safety of bilateral arm pressure measurements in the diagnostic workup of dialysis-associated steal syndrome.

Although bilateral brachial pressure measurement is routinely included in the diagnostic work-up of upper extremity ischemia, it is generally avoided in the presence of hemodialysis access due to fears of inducing access thrombosis. This study evaluated the safety of bilateral brachial pressure measurement in patients with clinical suspicion of dialysis-associated steal syndrome (DASS). Patients undergoing non-invasive testing for steal syndrome between September 2015 and December 2021 were included in this study. The diagnostic workup was performed by certified vascular sonographers in an outpatient vascular lab and consisted of bilateral brachial pressures, photoplethysmography, and duplex ultrasonography of the access. Interarm differential (IAD) was defined as systolic blood pressure (SBP) in the contralateral arm minus SBP in the access arm. The primary endpoint was immediate access thrombosis. The study sample consisted of 331 subjects with a mean age of 61 ± 13 and a median access age of 9 months (3-31 months) with radiocephalic fistulas present in 29%. Many patients (68%) presented with paresthesia and 4% presented with tissue loss. The mean brachial systolic pressure was 152 ± 37 mmHg on the ipsilateral arm versus 143 ± 34 mmHg on the contralateral (p-value <0.001), with an inter-arm differential (IAD) of -8.4 ± 19 mmHg. A total of 16 subjects (5%) presented a differential ⩾20 mmHg. A positive thrill was noted in all the accesses immediately following blood pressure measurement and no occurrence of access thrombosis was noted at 30 days. Proximal arterial revascularization interventions were performed in 11 cases (3%). Subjects who presented an IAD ⩾20 mmHg had lower ipsilateral digital-brachial index (0.39 ± 0.18 vs 0.68 ± 0.26; p = 0.037), a higher tendency of being referred for angiograms (37.5% vs 10.5%, p = 0.006), and more proximal arterial revascularization procedures (25.0% vs 2.2%, p = 0.001). Bilateral arm pressure measurement in the context of dialysis access-associated steal syndrome (DASS) appears safe and useful for identifying subjects whose symptoms are due to proximal arterial inflow disease. We therefore recommend this test be considered in the diagnostic algorithms of DASS.

The Role of Ultrasound Examination in the Assessment of Suitability of Calcified Arteries for Vascular Access Creation-Mini Review.

Arterial calcifications are present in 20-40% of patients with end-stage kidney disease and are more frequent among the elderly and diabetics. They reduce the possibility of arterio-venous fistula (AVF) formation and maturation and increase the likelihood of complications, especially distal ischemia. This review focuses on methods for detecting arterial calcifications and assessing the suitability of calcified arteries for providing inflow before the construction of an AVF. The importance of a clinical examination is stressed. A grading system is proposed for quantifying the severity of calcifications in the arteries of the arm with B-mode and Doppler ultrasound exams. Functional tests to assess the suitability of the artery to provide adequate inflow to the AVF are discussed, including Doppler indices (peak systolic velocity and resistive index during reactive hyperemia). Possible predictors of the development of distal ischemia are discussed (finger pressure, digital brachial index, acceleration and acceleration time), as well as the outcomes of AVFs placed on calcified arteries. It is concluded that a noninvasive ultrasound examination is probably the best tool for a morphologic and functional assessment of the arteries. An arterial assessment is of utmost importance if we are to create distal radiocephalic AVFs in our elderly patients whenever possible without burdening them with futile surgical attempts.

The Iatrogenic Injury Potential of Self-adherent, Elastic Bandages in Finger Injuries.

The use of a self-adherent, elastic bandage is a practical way to dress finger injuries. Multiple reports describe iatrogenic injuries from elastic bandages, ranging from skin necrosis to finger gangrene, necessitating amputations. This study investigated whether elastic bandages can compromise digital perfusion by occluding arterial blood flow in healthy volunteers and evaluated the utility of pulse oximetry as a monitoring tool for digital perfusion. A technique for safe bandage application is proposed. A commercially available elastic bandage was wrapped around the index finger of 20 healthy volunteers at varying degrees of stretch. Digital perfusion measurements were carried out using photoelectric pulse transduction, laser Doppler flowmetry, and pulse oximetry. Intracompartmental pressure measurements were recorded using a separate in vitro experimental model. Elastic bandages applied at maximum stretch did not change digital brachial index or pulse oximetry values, suggesting arterial blood flow was preserved distal to the bandage. Intracompartmental pressure measurements at maximum stretch remained below the systolic digital pressure. In contrast, superficial dermal perfusion fell to 32% of normal as measured by laser Doppler flow, at 100% bandage stretch. This study suggests a risk for iatrogenic injury when using elastic bandages for finger dressings. While arterial inflow was never compromised, pressures were high enough to occlude superficial venous outflow, which may begin at 20% bandage stretch. Pulse oximetry failed to detect changes distal to applied dressings, and we do not recommend it to detect digital vascular compromise in this setting.

An Abnormal Pre-Operative Digital Brachial Index is Associated With a Lower Two Year Access Patency: Vascular Access

Introduction: Sufficient brachial artery pressure (Pbrachial) is important for adequate maturation of an arteriovenous fistula (AVF) for haemodialysis (HD). Finger pressures (Pdig) or digital brachial index (DBI; Pdig/Pbrachial) are used to quantify deficits in hand perfusion or to determine the efficacy of surgery for HD access induced distal ischaemia (HAIDI). The aim of this study was to assess whether a single measurement of DBI in patients scheduled to receive an AVF predicted access patency rates.

Approximation of the Ankle-Brachial Index in the Setting of Medial Arterial Calcific Sclerosis

The presence of medial arterial calcific sclerosis is known to cause inaccuracy in the interpretation of noninvasive vascular testing. This substantially limits the utility of an important baseline diagnostic test for peripheral arterial disease. Therefore, the objective of this investigation was to derive a method to effectively factor out calcification in the interpretation of the ankle and digital brachial indices. The noninvasive vascular testing results of 160 subjects were stratified into the absence of calcification, mild calcification, moderate calcification, and severe calcification based on plain film radiographic findings of the infrageniculate vessels. Measurements were then performed of the pulse volume recording (PVR) waveforms at brachial, ankle and digital anatomic levels to include PVR wavelength and PVR upstroke length, with a calculation of the ratio of PVR upstroke length to PVR wavelength. These measurements were compared between groups and then correlated to the ankle and digital brachial indices. A significant difference was observed in the PVR upstroke ratio between the 3 anatomic levels (0.1818 vs 0.2622 vs 0.3191; p < .001), but not between the 4 calcification groups (0.2457 vs 0.2363 vs 0.2694 vs 0.2631; p = .242). A significant negative correlation was observed between the PVR upstroke ratio and the ankle brachial index (ABI) (Pearson -0.454; p = .002) with linear regression indicating the relationship is defined by the formula: Effective ankle brachial index = 1.17 – (1.33 × PVR upstroke ratio at ankle level). A significant negative correlation was also observed between the PVR upstroke ratio and the digital brachial index (Pearson -0.553; p < .001) with linear regression indicating the relationship is defined by the formula: Effective toe brachial index = 1.04 – (1.61 × PVR upstroke ratio at digital level). The results of this investigation demonstrate the feasibility of, and provide equations to approximate, the effective ankle brachial and toe brachial indices in the setting of medial arterial calcification.

Abnormal preoperative digital brachial index is associated with lower 2-year arteriovenous fistula access patency

ObjectiveThe aim of the present study was to assess whether a single measurement of the digital brachial index (DBI; systolic finger pressure/systemic pressure ratio), reflecting the arm's circulation, was associated with access patency in patients with severe chronic kidney disease scheduled for arteriovenous fistula (AVF) creation. MethodsA bilateral DBI was obtained using digital plethysmography just before construction of the patient's first AVF from January 2009 to December 2017 at one center. A DBI of 80% to 99% was considered normal, and a DBI of <80% (low) or DBI of ≥100% (high) were considered abnormal. DBI values ipsilateral to the AVF were used for analysis. The primary and secondary access patency rates were calculated using reported standards and compared using standard statistical techniques. ResultsData sets of 163 patients were obtained (69 women; age, 71 ± 12 years). The median follow-up was 40 weeks (range, 0-104 weeks; follow-up index, 99% ± 1%). Patients with abnormal preoperative DBI values had lower 2-year primary patency rates (low DBI, 25% ± 11%; high DBI, 28% ± 6%; normal DBI, 49% ± 8%; P = .018). After correction for age, sex, hypertension, diabetes mellitus, cardiovascular disease, smoking status, and a history of ipsilateral central venous catheter use, an adjusted model demonstrated that abnormal DBI values conferred an increased risk of primary patency failure (low DBI [<80%]: hazard ratio [HR], 2.25; 95% confidence interval [CI], 1.13-4.48; high DBI [≥100%]: HR, 1.74; 95% CI, 1.06-2.85; P < .030 for both). Patients with a low preoperative DBI had also had diminished secondary patency (HR, 2.86; 95% CI, 1.08-7.59; P = .035). In contrast, the diameters of the outflow veins did not determine access patency. ConclusionsPatients with abnormal DBI values before AVF construction for hemodialysis had lower 2-year access patency rates compared with patients with a normal DBI. Plethysmographic finger measurements might have a role in the preoperative counseling of patients with severe chronic kidney disease requiring an AVF.

Abnormal digital brachial index prior to hemodialysis access construction and cardiovascular mortality.

An abnormal ankle-brachial index indicating presence of peripheral arterial disease (PAD) is known to predict mortality in end-stage renal disease (ESRD). Hand ischemia, reflected by low finger pressures, is also a factor associated with increased mortality in patients undergoing hemodialysis (HD). The Aim of the present study is to determine whether an abnormal digital brachial index in ESRD patients prior to HD access surgery is related to lower survival rates. A digital brachial index (DBI, systolic finger pressure/systolic brachial arterial pressure) was obtained using digital plethysmography in ESRD patients before construction of a primary HD access between January 2009 and December 2018 in a single center. Patients were grouped based on categories of DBI (low <80%, normal 80-99%, high ≥100%). Overall and cardiovascular mortality were assessed with the ERA-EDTA classification system (ERA-EDTA codes 11, 14-16, 18, and 22-26, 29). Factors potentially influencing survival rates were analyzed using standard statistics. Follow-up was available in 199 patients (female n = 80; age 70 years ±12; follow-up index 99% ±1). Overall, 2 and 4 years survival were similar among DBI groups Moreover, 2 and 4 years freedom from cardiovascular death were also not different (low DBI 80% ±8 and 58% ±11; normal DBI 86% ±4 and 75% ±6; high DBI 74% ±6 and 61% ±7). Following correction for age, diabetes mellitus, cardiovascular disease and smoking, a high DBI conferred a significantly increased risk of cardiovascular mortality (HR 2.09 [1.06-4.13], P = 0.03) and a trend toward higher overall mortality (HR 1.69 [0.98-2.93], P = 0.06). ESRD patients with an abnormally elevated DBI before HD access creation have an increased risk of cardiovascular mortality in the first four postoperative years.

Comparison of the digital brachial pressure index and skin perfusion pressure as tools for diagnosing dialysis access steal syndrome

Comparison of the digital brachial pressure index and skin perfusion pressure as tools for diagnosing dialysis access steal syndrome

Correlation of Hand Ischemic Questionnaire with Digital Brachial Index In Patient with Upper Arm Native Arteriovenous Fistula

Introduction: Steal syndrome is one of the most feared complications in maintaining arteriovenous fistula (AVF) for hemodialysis. The incidence of steal syndrome in worldwide is estimated to be 0.5-5%. There are various non-invasive examinations to assess the degree of stealing, one of which is the digital brachial index (DBI). In this study, subjects with brachiocephalic AVF were assessed by the hand ischemic questionnaire (HIQ) to assess the manifestations of steal syndrome complained by the patient, which are the sensation of cold, pain, the decrease in sensation and strength, and cramps. The literature about the correlation of DBI with other assessment is still limited. Method: The subjects of this study were all patients undergoing hemodialysis with upper arm AVF at Cipto Mangunkusumo Hospital in the period May – June 2019. Patients will be asked about various symptoms of stealing syndrome, the severity, and also frequency, according to HIQ. The scores were then calculated, followed by scores of DBI measurements using a plethysmograph. The DBI values that considered to be meaningful as stealing syndrome were &lt;0.6. The correlation between the two parameters was then analyzed. Results: From demographic data, characteristics of patients with native AVF by sex were 37 (46.2%) men and 43 (53.8%) women with an average age of 53 years. The minimum value of the HIQ score was 0, and the maximum value was 70, with a median value of 3. The correlation test between the total value of the HIQ questionnaire score and the DBI value found a significant correlation (r = -0.0798, p &lt;0.001). A diagnostic tests was performed between HIQ scores using a cut-off value ≥50 with a DBI value &lt;0.6 as a reference. It was obtained a sensitivity value of 15.3% and a specificity value of 100%, with a diagnostic accuracy of 58.75%. Conclusion: There was a good correlation between HIQ and DBI in patients undergoing hemodialysis using upper arm native AVF. The use of HIQ as a screening tool in native upper arm AVF patients is less recommended, but its use for patients who are suggestive of stealing syndrome has good specificity results. Keywords: digital brachial index, hand ischemic questionnaire, native arteriovenous fistula upper arm.

Digital pressure in haemodialysis patients with brachial arteriovenous fistula.

Background & objectives:The pathophysiological mechanisms involved in distal pressure changes following arteriovenous fistula (AVF) creation in patients with end-stage renal disease (ESRD) are not completely understood. This study was aimed to assess digital pressure changes post-AVF creation and to identify the factors that might influence these changes in ESRD patients.Methods:In this prospective study, 41 patients with ESRD underwent AVF creation. Basal digital pressure (BDP), digital brachial index (DBI), calcium, phosphorus and blood urea levels were assessed preoperatively. BDP, DBI, vein and artery diameters, and AVF blood flow were also evaluated at one and two month(s) post-AVF creation.Results:Mean BDP significantly decreased from 131.64±25.86 mmHg (baseline) to 93.15±32.14 and 94.53±32.90 mmHg at one and two months post-AVF creation, respectively (P<0.001). Mean DBI significantly decreased one month post-AVF creation versus baseline (0.70±0.18 vs. 0.89±0.17 mm, P<0.001) and remained similar at two versus one month(s) postoperatively (0.70±0.23 vs. 0.70±0.18 mm). At both postoperative timepoints, no correlation between DBI decrease and increased artery and vein diameters or fistula blood flow was observed. Mean DBI difference between patients with previous ipsilateral access versus those without was not significant from pre to one month postoperatively. No correlation was observed between baseline phosphorus, calcium and blood urea nitrogen and DBI changes.Interpretation & conclusions:Our findings suggest that decrease in distal pressure following AVF creation may not be influenced by the arterial remodelling degree, vein diameter or fistula flow. In uraemic patients, those with low calcium and/or increased phosphorus, no association between these parameters and DBI changes could be observed.

Quantitative evaluation of the systemic effects of transposed basilic vein to brachial artery arteriovenous fistula: a prospective study.

The transposed basilic vein to brachial artery arteriovenous fistula (BBAVF) constitutes an alternative autogenous vascular access (VA) site for chronic hemodialysis (HD); however, the hemodynamic effects of this procedure have not been adequately studied. The purpose of this study is to evaluate the effects of BBAVF on systemic arterial pressure, cardiac function, and upper limb ischemia (ischemic steal syndrome) utilizing reproducible quantitative methods. Ten consecutive patients (eight males; mean age: 65.10+/-2.87 yrs) scheduled to undergo a brachial-basilic vein transposition were included, excluding patients with cardiac failure. Blood flow volume at the level of the AVF, systemic arterial pressure (SAP), cardiac output (CO) and digital brachial index (DBI) were measured intra-operatively, before and after the creation of the BBAVF, and post-operatively on the 30th post-operative day and on the 3rd post-operative month. SAP and DBI at 30 days and 3 months post-operatively were significantly lower compared to baseline. CO at 30 days and 3 months post-operatively was significantly higher compared to baseline; however, none of the patients developed cardiac failure. DBI remained >or=0.6 at 3 months, except in one case (0.59). Blood flow volume at the level of the AVF was positively correlated with CO levels on the 30th post-operative day. Mean clinical follow-up was 12 months (range: 4-15 months). In two cases (20%) the AVF was thrombosed (4th and 10th post-operative month). This prospective quantitative study proves that the BBAVF does impact significantly upon SAP, CO, and DBI; however, it is safe in terms of high-output cardiac failure and ischemic steal syndrome. The authors state that they do not have any commercial, proprietary, or financial interest in any products or companies described in this article.

Basilic vein transposition for unsuitable upper arm hemodialysis needle access segment may attenuate concurrent hand ischemia

Some hemodialysis patients with a brachial arteriovenous fistula (AVF) have an unsuitable upper arm needle access segment (NAS) necessitating basilic vein transposition (BVT). It was frequently observed that a portion of these patients spontaneously experienced a warmer and less painful dialysis hand after BVT. Aim of this study was to determine whether BVT for an inadequate NAS attenuated hemodialysis access-induced distal ischemia in patients with a brachial AVF. Patients with a brachial AVF and an unsuitable NAS also reporting hand ischemia and scheduled to undergo BVT between 2005 and 2016 in a single facility were studied. Hand ischemia was graded as proposed in a 2016 consensus meeting. Hand ischemic questionnaire (HIQ-) scores (0 points, no ischemia-500 points, maximal ischemia), digital brachial index (DBI, ischemia <0.6) and access flow (mL/min) before and after BVT were compared. The cephalic vein and all side branches of the basilic vein were ligated during the BVT. Ten patients were studied (8 males, 61 [54-75] years). BVT was performed 8 [4-10] months following the initial AVF construction. HIQ-scores dropped from 220 [71-285] to 9 [0-78] (P = 0.043) postoperatively, whereas DBI increased from 0.51 [0.39-0.67] to 0.85 [0.68-0.97] (P = 0.012). DBI and HIQ-scores were inversely correlated (R2 =71%, P = 0.001). Access flows dropped significantly (Flowpre 1120 mL/min [1100-2300] vs. Flowpost 700 mL/min [600-1760]; P = 0.018). Surgery-associated complications were absent and dialysis continued uninterruptedly. Eight patients reported total recovery from hand ischemia six weeks postoperatively. Basilic vein transposition for an unsuitable upper arm needle access segment may attenuate hand ischemia in patients with a brachial AVF previously reporting hemodialysis access-induced distal ischemia.

Upper Extremity Arterial Testing: The Diagnostic Criteria for the Physiologic Examination

Upper extremity arterial disease is relatively uncommon compared with lower extremity disease, but presents a unique diagnostic challenge for physicians and technologists. It affects approximately 5–10% of the population. The most common causes of upper extremity arterial disease are atherosclerosis and embolic disease. Some common symptoms of upper arterial disease include dysesthesia, paresthesia, pallor, cold intolerance, ulceration, pain, or weakness in one or both extremities. The vascular system plays a vital role in the delivering of nutrients and clearing metabolic waste products from the peripheral tissues and also helps maintain an individual's systemic core temperature. In a majority of patients, the deep and superficial palmar arches provide the dominant blood supply to the hand. The arches are a continuation of the radial and ulnar arteries. These arches are typically connected in approximately 80% of patients. In order to accurately diagnose upper extremity arterial disease, a noninvasive upper extremity physiologic examination is of importance to determine treatment options for patients. The physiologic examination includes upper extremity segmental pressures known as wrist-brachial index, Doppler waveforms; digital evaluations include photoplethysmography and pressures of the digits known as the digital-brachial index. Physiologic tests are indirect examinations. The upper extremity arterial physiologic examination is always completed bilaterally in order to determine if the disease is present in one or both extremities and also assists in the diagnosis of disease severity. The vascular physiologic examination should focus on the symptoms presented by the patient during the history. However, a complete vascular examination is appropriate given the diffuse nature of the atherosclerotic disease process.

A comparison of revision using distal inflow and distal revascularization-interval ligation for the management of severe access-related hand ischemia

Access-related hand ischemia (ARHI) is a potentially limb-threatening complication of arteriovenous access for dialysis. The distal revascularization-interval ligation (DRIL) and revision using distal inflow (RUDI) procedures both allow treatment of ischemic symptoms while maintaining fistula patency. Although outcomes with the DRIL are well established, experience with the RUDI for ARHI remains preliminary. We compared outcomes in these procedures with respect to cumulative patency, resolution of symptoms, and patient survival. A large, prospectively maintained database was used to identify all patients after autogenous arteriovenous fistula construction at two hospitals between 2005 and 2015. Patients with severe Society for Vascular Surgery grade 3 ARHI were included for analysis. A total of 2035 autogenous accesses were created during the study period, and 58 (3%) developed grade 3 ARHI. Of this cohort, RUDI was performed in 20 and DRIL in 21. The indication for intervention was tissue loss (61%) or ischemic rest pain (39%). Mean age was 57.5years, and 54% of patients were female. Most patients had diabetes (86%) and symptomatic peripheral arterial disease (63%). The mean preoperative digital-brachial index was 0.25± 0.12. There were no preoperative differences in patient comorbidities between the RUDI and DRIL cohorts. Primary patency between the RUDI and DRIL cohorts at 12months (58%± 11% vs 55%± 12%) and 36months (51%± 12% vs 41%± 12%) were similar (P= .841). Cumulative secondary patency at 12months (84%± 8% vs 94%± 6%) and 36months (78%± 9% vs 86%± 9%) showed no significant difference (P= .398). Resolution of ischemic symptoms, including resolution or improvement in pain or healing ofischemic ulcers or amputations, occurred in 90% with RUDI and in 81% with DRIL (P= .131). Survival for patients who underwent RUDI or DRIL procedures at 1 and 3years was 85% vs 86% (P= .948) and 55% vs 49% (P= .278). In this preliminary study, the RUDI demonstrated similar patency, symptom resolution, and survival compared with the DRIL for patients with severe ARHI. All-cause mortality after any procedure for severe steal syndrome is high, and the particular intervention for management of steal must account for anatomic-, patient-, and disease-related considerations.

Venous Side Branch Ligation as a First Step Treatment for Haemodialysis Access Induced Hand Ischaemia: Effects on Access Flow Volume and Digital Perfusion

Haemodialysis access induced distal ischemia (HAIDI) induced by an autogenous arteriovenous fistula (AVF) is caused by loss of blood pressure somewhere along the arterial blood supply of the arm. In some patients, side branches of the access' venous outflow tract may contribute to this blood pressure loss. Beneficial effects of side branch ligation (SBL) as a first step approach to ischemic symptoms have been reported. However, effects on access flow and AVF function after prolonged follow up are unknown. Prior to SBL, HAIDI patients with a brachial artery based AVF were studied using a questionnaire quantifying hand ischemia, digital brachial index (DBI, finger plethysmography), and Duplex analysis. Access flow volume, patency rates, hand perfusion, and complications were determined during a 12 month observation period following SBL. In 9 years, SBLs were performed in 20 haemodialysis patients, either as a single operative procedure (n=10) or supplemented (n=10) with additional surgical techniques during the same procedure (banding, n=5; basilic vein transposition, n=4; DRIL, n=1). Follow up data after 12 months were available in 18 patients. One patient with progressive hand ischemia required access ligation 3 months after SBL. Hand ischemia was attenuated or abolished in the remaining 17 patients (94% clinical success rate). DBI improved from 0.51±0.05 (pre-operative) to 0.68±0.04 (immediate post-operative) and 0.83±0.07 (at 1 year follow up). One year primary, assisted primary, and secondary patency rates were 67% (12/18), 83% (15/18), and 94% (17/18), respectively, while mean access flows remained acceptable at 710±70mL/min. Ligation of non-functional venous side branches of an autogenous brachial artery AVF causing hand ischemia leads to prolonged attenuation of hand ischemia whereas access flow volumes are maintained after 1 year of follow up. Side branch ligation must be considered prior to embarking on more invasive surgery for HAIDI.

Digital pressure and oxygen saturation measurements in the diagnosis of chronic hemodialysis access-induced distal ischemia

Hemodialysis access-induced distal ischemia (HAIDI) can be classified as acute (on the first postoperative day), subacute (≤1 month), or chronic (>1 month), based on the time of onset after access creation. The diagnosis is mainly clinical. However, performing additional tests is beneficial in further assessment of patients. The purpose of this study was to evaluate the use of finger pressure and oxygen saturation measurements for the diagnosis of chronic HAIDI. A total of 20 patients with chronic HAIDI (cases) and 40 asymptomatic hemodialysis patients (controls) were matched for age, sex, etiology of end-stage renal disease, and type of arteriovenous access. Basal digital pressure (BDP), digital pressure during manual compression of access, digital brachial index (DBI), change in digital pressure with access compression (CDP), digital pressure of the contralateral side, and bilateral oxygen saturation (O2 Sat) were measured in all patients. In the case group, compression of the arteriovenous fistula (AVF) increased mean BDP from 61 ± 26 to 118 ± 28 mm Hg (P < .001), which failed to reach the non-AVF side mean digital pressure of 151 ± 25 mm Hg (P < .001). In addition, O2 Sat of the AVF side was significantly lower than the contralateral side (92.9% ± 2.1% vs 95.6% ± 1.4%; P = .001). Among the controls, manual AVF compression raised the mean BDP from 114 ± 36 mm Hg to 133 ± 29 mm Hg (P < .001), which was still significantly lower than the contralateral side mean digital pressure of 141 ± 30 mm Hg (P = .002). In addition, O2 Sat values of the two sides were different (96.7% ± 2.1% vs 97.1% ± 1.9%; P = .01). Comparing the cases and controls, the mean BDP (61 ± 26 mm Hg vs 114 ± 36 mm Hg; P < .001), DBI (0.44 ± 0.16 vs 0.82 ± 0.19; P < .001), and O2 Sat (92.9% ± 2.1% vs 96.7% ± 2.1%; P < .001) were significantly lower and CDP (57 ± 24 mm Hg vs 19 ± 17 mm Hg; P < .001) was significantly higher in the cases than in the controls. The optimal discriminatory thresholds of 80 mm Hg for BDP, 0.7 for DBI, 40 mm Hg for CDP, and 94% for O2 Sat were determined. Digital pressure and O2 Sat measurements are useful additional methods to assist in the clinical evaluation of hemodialysis patients with access-related hand ischemia. BDP <80 mm Hg, DBI <0.7, CDP >40 mm Hg, and O2 Sat <94% are associated with chronic HAIDI.

Blood flow dynamics in patients with hemodialysis access-induced hand ischemia

Hand ischemia may occur in the presence of a hemodialysis arteriovenous fistula (AVF), but its pathophysiology is partly unclear. The aim of this observational study was to investigate flow characteristics of forearm arteries in patients with a brachial artery-based AVF suffering from hemodialysis access-induced distal ischemia (HAIDI). A questionnaire scored hand ischemia in patients with HAIDI scheduled for revisional surgery (no symptoms of ischemia, 0 points; maximal ischemia, 500 points). Systolic index finger pressures (Pdig) and digital brachial index (DBI) were determined with open and compressed AVF. Blood flow direction and peak systolic velocity (PSV) were measured in radial and ulnar arteries using Doppler ultrasonography. Age- and sex-matched hemodialysis patients without HAIDI served as controls (CONT). Questionnaire scores were 258 ± 30 in patients with HAIDI (n = 10) compared with 31 ± 16 in CONT (n = 10; P < .01). Pdig and DBI with open AVF were lower in the HAIDI group than the CONT group (Pdig 22 ± 10 vs 102 ± 10 mm Hg; DBI 0.18 ± 0.08 vs 0.70 ± 0.04; both P < .01). Ulnar artery PSV was lower in HAIDI compared with CONT patients (38 ± 4 vs 56 ± 3 cm/s; P < .01). Mean ulnar artery PSV was significantly correlated to Pdig (r = 0.87; P < .01) in contrast to mean radial artery PSV (r = 0.06; P = .81). Ulnar artery blood flow direction was always toward the ischemic hand (n = 20). However, blood flow was reversed in just a short segment of the proximal radial artery in one HAIDI patient but also in two CONT patients. Hand ischemia in hemodialysis patients with a brachial artery-based AVF is not caused by a reversed blood flow direction in forearm arteries. However, forearm blood flow is diminished in these patients leading to critically reduced arterial pressures in the hand.

Prediction of graft patency and mortality after distal revascularization and interval ligation for hemodialysis access-related hand ischemia

The treatment goals of access-related hand ischemia (ARHI) are to reverse symptoms and salvage the access. Many procedures have been described, but the optimal treatment strategy remains unresolved. In an effort to guide clinical decision making, this study was undertaken to document our outcomes for distal revascularization and interval ligation (DRIL) and to identify predictors of bypass patency and patient mortality. A retrospective review was performed of all patients who underwent DRIL at the University of Florida from 2002 to 2011. Diagnosis of ARHI was based primarily upon clinical symptoms with noninvasive studies used to corroborate in equivocal cases. Patient demographics, procedure-outcome variables, and reinterventions were recorded. Bypass patency and mortality were estimated using cumulative incidence and Kaplan-Meier methodology, respectively. Cumulative incidence and Cox regression analysis were performed to determine predictors of bypass patency and mortality, respectively. A total of 134 DRILs were performed in 126 patients (mean [standard deviation] age, 57 [12] years) following brachial artery-based access. The postoperative complication rate was 27% (19% wound), and 30-day mortality was 2%. The wrist-brachial index and digital brachial index increased 0.31 (0.25) and 0.25 (0.29), respectively. Symptoms resolved in 82% of patients, and 85% continued to use their access. Cumulative incidences (± standard error of the mean) of loss of primary and primary-assisted patency rates were 5%± 2% and 4%± 2% at 1 year and 22%± 5% and 18%± 5% at 5 years, respectively, with mean follow-up of 14.8 months. Univariate predictors of primary patency failure were DRIL complications (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.2-8.9; P= .02), configuration other than brachiobasilic/brachiocephalic autogenous access (OR, 3.4; 95% CI, 1.4-8.3; P= .009), and two or more prior access attempts (OR, 4.1; 95% CI, 1.6-10.4; P= .004). Brachiocephalic access configuration (OR, 0.2; 95% CI, 0.04-0.8; P=.02) and autogenous vein conduit (OR, 0.2; 95% CI, 0.06-0.58; P= .004) were predictors of improved bypass patency. All-cause mortality was 28% and 79% at 1 and 5 years, respectively. Multivariable predictors of mortality were age >40 (hazard ratio [HR], 8.3; 95% CI, 2.5-33.3; P= .0004), grade 3 ischemia (HR, 2.6; 95% CI, 1.5-4.6; P= .0008), complication from DRIL (HR, 2.4; 95% CI, 1.3-4.5; P= .004), and smoking history (HR, 2.2; 95% CI, 1.3-4; P=.007). Patients with no prior access attempts had lower predicted mortality (HR, 0.5; 95% CI, 0.3-0.9; P= .02). The DRIL procedure effectively improves distal perfusion and reverses the symptoms of ARHI while salvaging the access, but the long-term survival of these patients is poor. Given the poor survival, preoperative risk stratification is critical. Patients at high risk for DRIL failure and mortality may be best served with alternate remedial procedures.

Side Branch Ligation for Haemodialysis-access-induced Distal Ischaemia

ObjectiveChronic hand ischaemia is occasionally observed in haemodialysis patients with a brachiocephalic fistula using the Gracz technique. Open venous side branches of the access may contribute to lower peripheral perfusion pressures. This study reports on the effects of access side branch ligation (SBL) on ischaemia in patients with haemodialysis access induced distal ischaemia (HAIDI). Design, materials and methodsHand ischaemia was quantified using a published questionnaire (HIQ, minimal 0 points: no ischaemia, maximal 500: excruciating ischaemia). Finger pressures (Pdig, mmHg), digital brachial index (DBI) and access flow were measured before and after SBL. ResultsTwenty-two patients were operated for grade 2–4 HAIDI during 7 years, and 12 underwent SBL (as single procedure n = 5, preceeding banding/DRIL n = 7). Hand ischaemia was attenuated after SBL only (n = 5, HIQ 216 ± 39 vs. 73 ± 26, P = 0.04). A 25% increase was observed in both Pdig (n = 12, before SBL: 57 ± 8 mmHg, after: 72 ± 8 mmHg, P = 0.012) and DBI (before SBL: 0.49 ± 0.06, after: 0.61 ± 0.04, P = 0.006). Access flow did not change. All patients successfully resumed dialysis. ConclusionSBL may be effective as single or adjunctive surgical procedure in the treatment of HAIDI in the presence of a Gracz fistula.