Evaluation of Clinical Outcomes Following Minor Amputations in Australia - An Important Consideration for Timing of Revascularisation.

BACKGROUND: Vascular patients with tissue loss requiring minor amputations could be an early sign of a terminal event. The long-term outcomes and timing of revascularisation for these patients are not well-studied. The aim of this study was to determine the clinical outcomes following minor amputations. Primary outcomes were functional status, limb loss, and mortality. Secondary outcomes compared immediate and delayed revascularisation. METHODS: A retrospective analysis of 200 vascular patients who required minor amputations at Austin Hospital, Melbourne was performed over 5 years. Demographics, details of revascularisation, functional status, and clinical outcomes such as recurrent tissue loss, limb loss and death were recorded. RESULTS: Of the entire cohort requiring minor amputations, 118 (59%) patients underwent revascularisation. 111 (94%) revascularisation procedures were performed within 90 days of minor amputation. Over all 5-year limb preservation was 89.9%. Patients who required revascularisation were not statistically significantly more at risk for limb loss at 5 years [13.6% vs. 6.6%; P=0.08]. Limb salvage at 1 year was not different between groups revascularized before and after amputation [89.5% vs. 90.9%; P=0.70]. Over all 5-year mortality rate was 50%. In the diabetic subset, those who had revascularisation after minor amputation had a greater 5-year mortality [67.9% vs. 50%; P=0.03]. A scoring system based on risk factors was developed but was not reliable based on the study data. CONCLUSIONS: The data from this study suggest that patients with diabetes who undergo revascularisation after minor amputation have worse outcomes than those revascularised prior to minor amputation. A predictive model applied at presentation could help detect high-risk patients but requires further work.

Acute Upper Limb Ischemia Due to Delayed Presentation of a Brachial Artery Pseudoaneurysm Post-Venipuncture.

Brachial artery pseudoaneurysms (BAPs) are rare but could lead to complications of high morbidity. We report a case of a BAP presenting with hand ischemia and median nerve neuropathy nearly a decade after the inciting iatrogenic trauma, successfully treated with excision and direct repair. This report highlights that untreated pseudoaneurysms can be indolent and present late with both symptoms of embolization and local compression.

A Fine Needle Recanalization Technique for Iliac Artery Occlusions in Endovascular Surgery.

BACKGROUND: Endovascular intervention for chronic total occlusions (CTOs) in aortoiliac occlusive disease (AIOD) poses technical challenges. In this manuscript, our experience of fine needle recanalization for the treatment of iliac artery CTO is described. METHOD: A prospective database recorded treatment of 11 limbs in 11 patients since 2011 using this technique. The majority of these CTO were of the common iliac artery (n = 9). RESULTS: Technical success rate was 91% (n = 10). One failed case was due to tortuous iliac anatomy. There was no restenosis of the treated segments at 8 weeks and no major complications, perforations, major limb loss, or periprocedural mortality. CONCLUSIONS: This technique is a safe and viable adjunct for difficult CTO in AIOD with suitable anatomy. It benefits from being a simple, low-profile, low-cost coaxial system and should be part of the armamentarium with other advanced endovascular techniques.

Vein diameter is a predictive factor for recanalization in treatment with ultrasound-guided foam sclerotherapy.

OBJECTIVE: Ultrasound-guided foam sclerotherapy (UGFS) is a low-cost and minimally invasive treatment option for varicose veins. There is a relative paucity of outcome reports. METHODS: UGFS procedures at a tertiary public hospital between 2010 and 2017 were studied. Either the great saphenous vein (GSV) or small saphenous vein (SSV) was treated. Pretreatment, in-treatment, 6-week, and 1-year post-treatment ultrasound reports were analyzed. The primary outcome was to determine whether vein diameter predicts obliteration failure. RESULTS: There were 457 treatments completed in 290 patients. The GSV was targeted in 372 (81%). Mean vein diameters of the GSV were not different from those of the SSV (GSV, 5.7 mm; SSV, 6.2 mm; P = .18); 109 (24%) had a Clinical, Etiology, Anatomy, and Pathophysiology score of at least 4. Of the 457 UGFS procedures, 360 (78.8%) were for primary veins. Baseline information, including vein diameter, was not different between primary and recurrent veins. At 6 weeks, complete obliteration, partial recanalization, and complete recanalization rates were 54.9%, 29.1%, and 16%, respectively. Of those with complete obliteration at 6 weeks, the recanalization rate at 1 year was 25%. Increasing vein diameter was associated with recanalization at 1 year (obliteration, 4.9 mm; recanalization, 5.7 mm; P = .03), especially for primary veins (4.8 vs 5.8 mm; P = .009). Multivariate analysis showed similar outcome. Vein diameter of >6 mm had good specificity (88%) but poor sensitivity (43%) for predicting obliteration failure. There were 15 (3%) new-onset deep venous thromboses reported on follow-up, all of which were from treatment of primary veins (P = .049). CONCLUSIONS: Only 44% of UGFS procedures were observed to have complete obliteration at 1 year after a single intervention. Significant recanalization developed at 1 year. Increased vein diameter was associated with recanalization. The impact on clinical recurrence is unknown.

Clinical Evaluation of Portable Wound Volumetric Measurement Devices.

OBJECTIVE: Wound dimensional assessments are important in determining the progress of a wound and the effect of interventions on wound healing. The FastSCAN (FS; Polhemus Inc, Colchester, Vermont) and Silhouette Mobile (SM; ARANZ Medical, Christchurch, New Zealand) are portable devices that quantify surface area, depth, and volume of wounds. This study evaluated their reliability in producing accurate wound measurements. DESIGN AND SETTING: This study was conducted at the Waikato Hospital, Hamilton, New Zealand. PATIENTS AND INTERVENTION: Eleven vascular patients with a combined total of 16 wounds underwent simultaneous wound measurements using three-dimensional computed tomography (CT) reconstruction, FS, and SM. MAIN OUTCOME MEASURE: The validity of FS and SM was tested against CT. Additionally, the interoperator reliability and intraoperator reliability of FS and SM were determined. MAIN RESULTS: The intraoperator reliability and interoperator reliability for volume recordings of the SM were 0.97 and 0.97, respectively, and for the FS were 0.96 and 0.97, respectively. The FS and SM measurements were not significantly different from CT. The SM consistently produced smaller wound volume and depth measurements compared with CT. In contrast, overestimation was observed for FS when compared with CT. However, the volume measurements in one wound were anomalous, being 10 times larger than CT measurements. Excluding this wound, there were strong correlations in wound volumes for SM and CT (r = 0.81; P ≤ .0001), for FS and CT (r = 0.99; P ≤ .001), and for SM and FS (r = 0.99; P ≤ .0001). CONCLUSIONS: Measurements from FS and SM were comparable to CT. Therefore, SM and FS devices both offer the benefit of being noncontact portable devices that produce reproducible and reliable readings.

Measuring Transcutaneous Oxygenation to Validate the Duration Required to Achieve Electrode Equilibration.

OBJECTIVE: The transcutaneous oxygenation measurement (TCOM) system is useful in assessing tissue viability. There are no clear recommendations regarding the duration required for the electrode to equilibrate and reliably evaluate tissue oxygenation values. The objective of this study was to validate the duration required to achieve electrode equilibration in a clinical setting. METHODS: Minute-by-minute recordings using TCOM (TCOM3; Radiometer Medical ApS, Brønshøj, Copenhagen) were obtained for 82 limbs in 50 participants. Twenty-five limbs were in patients with peripheral vascular disease; 30 were in patients with no known peripheral vascular disease; and 27 were in healthy volunteers. Transcutaneous partial pressure of oxygen and carbon dioxide (TcPO2 and TcPCO2) were recorded over a 15-minute period. RESULTS: Participants' TcPO2 decreased and TcPCO2 increased over time. Both changed in a nonlinear fashion, eventually settling at an "equilibrium" where the measurements became stable. The difference in proportional change of TcPO2 between minutes 14 and 15 was 0.8%, and for TcPCO2was 2.9%. Changes in TCOM measurements over time were similar among the 3 groups. CONCLUSIONS: This is the first study to target minute-by-minute variation in TcPO2 and TcPCO2 measurements. Recording for a minimum of 15 minutes allows a reliable period for the TCOM electrode to equilibrate to record absolute values and determine wound healing potential.

A Novel Technique for Sutureless Proximal Aortic Endograft Revision in Type 1A Endoleak.

Management of type 1A endoleaks can be challenging. In the endovascular era, this condition is expected to become more frequent. Conventionally, surgical explant of the endograft remains the "last-resort" surgical treatment when all endovascular or other open options are exhausted. Endograft removal is a difficult and morbid procedure. An alternative technique is described that involves cinching the endograft after disengagement of the proximal fixation hooks. The endograft is redeployed within a prosthetic aortic replacement graft with an overlapping zone. This can reduce complications such as from additional anastomoses, graft bleeding, prolonged clamping, operative time, and associated comorbidities.

Epidemiology and Outcomes of Abdominal Aortic Aneurysms in New Zealand: A 15-Year Experience at a Regional Hospital.

INTRODUCTION: Abdominal aortic aneurysms (AAA) account for approximately 400 deaths per year in New Zealand (NZ). Waikato Hospital caters to a diverse population comprising a high proportion of the indigenous Maori ethnic group considered to be at higher risk of mortality and morbidity. Despite these population factors, there is no screening program for AAA. The aim of this study was to further define the epidemiology and outcomes of AAA repairs in NZ to investigate the utility of implementing a population-specific screening program. METHODS: A retrospective study of all AAA repairs at Waikato Hospital between July 1996 and November 2010 was performed comparing long-term outcomes between Europeans and Maori considering acuity of presentation, age, gender, and type of repair. Perioperative and overall mortality data were obtained to generate Kaplan-Meier survival curves. RESULTS: 1,036 AAA repairs were performed. Maori presented younger (69.1 vs. 74.5, P < 0.001), had lower male predominance (1.6:1 vs. 3.5:1, P < 0.001), less elective repairs (44% vs. 67%, P < 0.001), and more ruptured AAA (RAAA) (40% vs. 21%, P < 0.001) despite the overall incidence of RAAA decreasing from 26% to 7.8% (P = 0.01). Maori had a lower postoperative 10-year survival compared to Europeans (17.4% vs. 36.5%, P < 0.001). There was an initial survival benefit for endoluminal over open repair but this converged at 4.9 years post repair. CONCLUSIONS: This study highlights the epidemiological trends and survival outcomes of AAA management in Maori and Europeans over 15 years. It provides further evidence supporting the consideration of a population-specific screening program in future.

Perioperative warming, oxygen, and Ilomedin on oxygenation and healing in infrainguinal bypass surgery.

BACKGROUND: Perioperative adjuncts are utilized across surgical specialities with the goal of improving patient outcomes. High-dose oxygen and extended warming are shown to increase wound collagen deposition during abdominal surgery. Prostacyclin is shown to improve limb salvage and patency rate in infrainguinal bypass (IIB) surgery. This study evaluated the impact of these adjuncts on healing and perfusion post IIB surgery. METHODS: This randomized controlled study allocated patients undergoing IIB surgery into three treatment arms (perioperative high-dose oxygen, extended warming, and a synthetic prostacyclin) or a control group. The primary outcome was accumulation of hydroxyproline (OHP, collagen surrogate marker) as collected in polytetrafluoroethylene implants on day 5. Secondary outcomes included levels of growth factors and cytokines, and tissue oxygenation of the wound and foot as measured by hyperspectral technology and ankle-brachial pressure index. Clinical outcomes were observed to day 30, with long-term follow-up of 12 mo. RESULTS: Seventy-one patients completed the study. Comparing treatment groups with the control at day 5, there were no differences in OHP, growth factors or cytokines levels, or improvement in tissue oxygenation at the surgical incision. However, there was more flow to the foot (HT-SUM (%) change) in the Ilomedin group compared to control (0% versus -14.6%, P = 0.045). HT-deoxy was higher at the peripheries in the oxygen and temperature groups, suggesting decreased tissue oxygenation. CONCLUSIONS: The perioperative treatments did not dramatically improve oxygenation or healing of the surgical wound in IIB surgery; however, Ilomedin may result in greater flow to the peripheries.

Effects of topical negative pressure therapy on tissue oxygenation and wound healing in vascular foot wounds.

OBJECTIVE: Topical negative pressure (TNP) therapy is widely used in the treatment of acute wounds in vascular patients on the basis of proposed multifactorial benefits. However, numerous recent systematic reviews have concluded that there is inadequate evidence to support its benefits at a scientific level. This study evaluated the changes in wound volume, surface area, depth, collagen deposition, and tissue oxygenation when using TNP therapy compared with traditional dressings in patients with acute high-risk foot wounds. METHODS: This study was performed with hospitalized vascular patients. Forty-eight patients were selected with an acute lower extremity wound after surgical débridement or minor amputation that had an adequate blood supply without requiring further surgical revascularization and were deemed suitable for TNP therapy. The 22 patients who completed the study were randomly allocated to a treatment group receiving TNP or to a control group receiving regular topical dressings. Wound volume and wound oxygenation were analyzed using a modern stereophotographic wound measurement system and a hyperspectral transcutaneous oxygenation measurement system, respectively. Laboratory analysis was conducted on wound biopsy samples to determine hydroxyproline levels, a surrogate marker to collagen. RESULTS: Differences in clinical or demographic characteristics or in the location of the foot wounds were not significant between the two groups. All patients, with the exception of two, had diabetes. The two patients who did not have diabetes had end-stage renal failure. There was no significance in the primary outcome of wound volume reduction between TNP and control patients on day 14 (44.2% and 20.9%, respectively; P = .15). Analyses of secondary outcomes showed a significant result of better healing rates in the TNP group by demonstrating a reduction in maximum wound depth at day 14 (36.0% TNP vs 17.6% control; P = .03). No significant findings were found for the other outcomes of changes in hydroxyproline levels (58.0% TNP vs 94.5% control; P = .32) or tissue perfusion by tissue oxyhemoglobin saturation (19.4% TNP vs 12.0% control; P = .07) at day 14. At 1 year of follow-up, there were no significant outcomes in the analysis of wound failure, major amputation, and overall survival rates between the two groups. CONCLUSIONS: In this pilot study, applying TNP to acute high-risk foot wounds in patients with diabetes or end-stage renal failure improved the wound healing rate in reference to wound depth. This suggests that TNP may play a role in enhancing wound healing. This study sets the foundation for larger studies to evaluate the superiority of TNP over traditional dressings in high-risk foot wounds.

Evaluation of hyperspectral imaging technology in patients with peripheral vascular disease.

BACKGROUND: Hyperspectral imaging technology is a novel method of using transcutaneous measurement of oxyhemoglobin (HT-Oxy) and deoxyhemoglobin (HT-Deoxy) concentrations to create a two-dimensional, color-coded "oxygen map." The aims of this study were to compare the use of a hyperspectral imaging device with the transcutaneous oxygen measurement (TCOM), ankle-brachial index (ABI), and severity of peripheral vascular disease (PVD) and to assess their correlations. METHODS: This prospective study recruited 294 participants divided into three distinct groups composed of healthy volunteers and patients with PVD. Patients underwent measurements of lower limbs at a standardized point over the head of the first metatarsal on the plantar aspect using the hyperspectral imaging device, generating four outputs including HT-Oxy, HT-Deoxy, oxygen saturation (HT-Sat), and skin temperature, and the TCOM system, generating transcutaneous partial pressure of oxygen (TcpO2) and carbon dioxide (TcpCO2). Demographic data, severity of PVD, ABI, and other pertinent information were obtained from both the participants and medical records. RESULTS: Interoperator reliability ranged from 86% to 94% across the four hyperspectral imaging device outputs, whereas intraoperator reliability ranged from 92% to 94%. The HT-Oxy, HT-Sat, TcpCO2, and ABI of the diseased limb correlated significantly with the severity of PVD. HT-Sat significantly correlated with TcpO2 (R = 0.19), TcpCO2 (R = -0.26), ABI (R = 0.42), and skin temperature (R = 0.56). HT-Deoxy also correlated with TcpCO2 (R = 0.27). CONCLUSIONS: This study demonstrates the reliability of hyperspectral imaging in comparison to TCOM, ABI, skin temperature, and severity of PVD in a series of patients. Its correlation to other established modalities and low interoperator and intraoperator variability could enable this modality to be a useful screening tool in PVD.

Comparison of FLIXENE™ and standard PTFE arteriovenous graft for early haemodialysis.

PURPOSE: The purpose is to compare the outcomes of FLIXENE™ arteriovenous graft (AVG) to standard polytetrafluoroethylene (PTFE) AVG for early haemodialysis. METHODS: This is a prospective observational study of all AVGs placed over a 40-month period between 2008 and 2011 at our vascular unit. Primary outcome was to examine early cannulation rates for FLIXENE™. Secondary outcomes included patency rates, usability of grafts, complications in particular infections, interventions and death in comparison to standard PTFE grafts. RESULTS: Forty-five FLIXENE™ and 19 standard PTFE AVGs were placed in the study period; 89% of FLIXENE™ grafts were used for dialysis, with 78% cannulated within 3 days. At 18 months, primary patency (FLIXENE™ 34% vs standard PTFE 24%), primary assisted patency (35% vs 36%) and secondary patency rate (51% vs 48%) were not statistically different; 20.2% of FLIXENE™ grafts were infected at 18 months requiring explantation compared with 40.3% of standard PTFE grafts (p=0.14). CONCLUSIONS: FLIXENE™ can be cannulated for dialysis within 3 days. It has similar patency and complication rates as other prosthetic grafts in the market. In patients who have no access and require urgent dialysis, FLIXENE™ is a viable option.

Evaluation of surgical performance using V-POSSUM risk-adjusted mortality rates.

Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (V-POSSUM) is a risk-adjusted scoring system for predicting 30-day mortality in patients undergoing vascular surgery. It can assess surgical performance by comparing predicted deaths with observed deaths. The aim of this analysis was to assess trends in surgical performance over time using risk-adjusted 30-day mortality as the primary outcome. Major vascular surgery procedures (n = 454) were prospectively scored for V-POSSUM between 1995 and 2006. Procedures were divided into 11 consecutive time bands. Observed and predicted deaths were compared using the logistic regression equation derived for V-POSSUM. The observed death rates decreased over time, as did the predicted number of deaths calculated from the V-POSSUM scores. The overall predicted mortality rate was 17.2% and the rate varied with the 12-month period, with a high of 23.9% and a low of 9.2%. The downward trend in the predicted rate shows that the patient risk factors have changed over time and that the risk of dying has declined by almost 50% (from 21.6 to 11.1%). There was a trend towards improved surgical performance over time, with a drop in the observed to predicted ratios of deaths. Observed and predicted deaths changed over the study periods. There was a trend towards improved performance compared with the risk-adjusted predicted mortality. V-POSSUM is a useful tool in the longitudinal assessment of performance in major vascular surgery.