Hisham Rashid

The impact of arterial pedal arch quality and angiosome revascularization on foot tissue loss healing and infrapopliteal bypass outcome

OBJECTIVE This study evaluated the effect of pedal arch quality on the amputation-free survival and patency rates of distal bypass grafts and its direct impact on the rate of healing and time to healing of tissue loss after direct angiosome revascularization in patients with critical limb ischemia (CLI). METHODS Between 2004 and 2011, patients undergoing distal bypass for CLI (Rutherford 4-6) were divided in groups taking into consideration the state of the pedal arch and direct angiosome revascularization (DAR) and non-DAR. Angiography was used to divide the pedal arch into three groups: complete pedal arch (CPA), incomplete pedal arch (IPA), and no pedal arch (NPA). The primary end points were patency rates at 12 months, amputation-free survival at 48 months, and the rate of healing and time to healing of foot tissue loss. RESULTS A total of 154 patients (75% men) with CLI underwent 167 infrapopliteal bypasses. Patients were a median age of 75 years (range, 46-96 years). Diabetic mellitus was present in 76%, chronic renal failure in 28%, and ischemic heart disease in 44%. The primary patency rates at 1 year in the CPA, IPA, and NPA groups were 58.4%, 54.6%, and 63.8%, respectively (P = .5168), the secondary patency rates were 86.0%, 84.7%, and 88.8%, respectively (P = .8940), and the amputation-free survival at 48 months was 67.2%, 69.7%, and 45.9%, respectively (P = .3883). Tissue loss was present in 141 of the 167 bypasses. In the CPA group, 83% of tissue loss with DAR healed compared with 92% in the non-DAR (median time to healing, 66 vs 74 days). Similarly in the IPA group, 90% with DAR healed compared with 81% in the non-DAR (median time to healing, 96 vs 86 days). In the NPA group, only 75% with DAR healed compared with 73% in the non-DAR (median time to healing, 90 vs 135 days). There was a significant difference in healing and time to healing between the CPA/IPA and NPA groups (P = .0264). CONCLUSIONS The quality of the pedal arch did not influence the patency or the amputation-free survival rates. However, the rates for healing and time to healing were directly influenced by the quality of the pedal arch rather than the angiosome revascularized.

Improving limb salvage rate in diabetic patients with critical leg ischaemia using a multidisciplinary approach.

Background:  Diabetic patients are more likely to develop critical leg ischaemia (CLI) and subsequently major amputation than the general population. Major amputation rate in this group is reported to be high compared with non‐diabetic patients with a devastating outcome.

Cerebral monitoring in patients undergoing carotid endarterectomy using a triple assessment technique

OBJECTIVES Selective shunting during carotid endarterectomy (CEA) is advocated to reduce shunt related stroke. Cerebral monitoring is essential for temporary carotid shunting. Many techniques are available for cerebral monitoring, however, none is superior to monitoring the patients neurological status (awake testing) while performing the procedure under local anaesthesia (LA). Cerebral oximetry (CO) and trans-cranial Doppler (TCD) has previously been used to show the adequacy of cerebral circulation in patients undergoing CEA. The aim of this study is to assess the reliability of CO and TCD in predicting the need for shunting compared to the awake testing. METHODS Patients scheduled for CEA under LA were included. Patients converted to general anaesthesia (GA) and patients with no TCD window were excluded from the study. The Somanetics INVOS(®) CO was used for ipsilateral cerebral monitoring in all patients, in addition to TCD and awake testing. The percentage fall in CO regional oxygen saturation (rSO(2)), and decline in the mean flow velocity (FVm) in TCD following carotid artery clamping recorded. A drop in rSO(2) of ≥20% or FVm of ≥50% was considered an indicator of cerebral ischaemia that may predict the need for carotid shunting. Patients only shunted based on awake testing. RESULTS Forty-nine patients underwent triple assessment. The median clamp time was 24 min. 8/49 patients (16.3%) needed carotid shunting based on awake testing. In this group, six patients had ≥20% drop in rSO(2), and ≥50% drop in FVm. However, two patients had a non-significant drop in both rSO(2) and FVm (false negative). In the non-shunted group (41/49), one patient had a significant drop in rSO(2) (false positive) while 10/41 patients had a >50% drop in FVm. This represents sensitivity of 75%, and specificity of 97.5% for CO compared to sensitivity of 75% and specificity of 75% for TCD in prediction of shunting. The positive predictive value and negative predictive value were 85.7 and 95.2%, respectively for CO, compared to 37.5 and 93.9% for TCD. CONCLUSIONS TCD is less accurate than CO in predicting the need for carotid shunting during CEA. A combination of both methods does not add to the accuracy of detecting the need for carotid shunting.

The role of cerebral oximetry in combination with awake testing in patients undergoing carotid endarterectomy under local anaesthesia.

INTRODUCTION The aim of this study is to analyse the role of cerebral oximetry in combination with awake testing in detecting cerebral ischaemia in patients undergoing carotid endarterectomy (CEA) under local anaesthesia (LA). METHODS One hundred consecutive patients scheduled for CEA under LA were investigated. Regional oxygen saturation (rSO(2)) was measured with a cerebral oximeter. Cerebral ischaemia was assessed by awake testing in conjunction with rSO(2). Shunting was based solely on deterioration in conscious state assessed by awake testing. The correlation between awake testing and percentage fall in rSO(2) levels was statistically analysed. RESULTS Patients requiring general anaesthesia were excluded from analysis (n = 17). Seven patients developed deterioration in conscious state and an immediate drop in rSO(2) ≥20% following carotid cross-clamping. Two patients requiring shunting for non-neurological reasons were excluded from analysis. Two patients had a drop in rSO(2) ≥20%, but remained conscious and were not shunted. There were no permanent neurological deficits postoperatively. Statistical analysis showed a sensitivity of 100% with a specificity of 96% yielding a positive predictive value of 81% and negative predictive value of 100% for a ≥19% drop in rSO(2). CONCLUSION Cerebral oximetry using a cut off ≥19% drop in rSO(2) has a high sensitivity and specificity when compared with awake testing.

Distal versus Ultradistal Bypass Grafts: Amputation-free Survival and Patency Rates in Patients with Critical Leg Ischaemia

OBJECTIVES Compare the outcome of distal (bypass to the crural arteries) versus ultradistal (bypass to the pedal arteries) bypasses in patients with critical leg ischaemia (CLI). DESIGN Retrospective analysis of prospectively collected data of patients with CLI undergoing infra-popliteal bypass surgery is performed. MATERIALS AND METHODS Patients undergoing infra-popliteal bypass at a single institution between 2004 and 2010 are included. Patency rates at 1-year and amputation-free survival at 12 and 48 months are analysed. RESULTS Two hundred and thirty bypasses were performed in 209 consecutive patients (156 men, median age; 76 years, range; 19-96 years). One hundred and seventy nine (78%) bypass were classified as distal and 51 (22%) as ultradistal. The incidence of diabetes mellitus was significantly higher in the ultradistal group (p=0.0025). At 1-year, the distal group primary, assisted-primary and secondary patency rates were 61.7%, 83.1% and 87.4% compared to 61.9%, 87.4% and 87.4% in the ultradistal group respectively. Amputation-free survival at 12 and 48 months was 82.9% and 61.5% in the distal group compared to 83.0% and 64.9% in the ultradistal group. CONCLUSIONS This study show that both distal and ultradistal bypass have comparable outcome regardless of the co-morbidities. The authors believe that elderly patients should be offered ultradistal bypass if indicated to avoid major amputation.

Outcome of infra-inguinal bypass grafts using vein conduit with less than 3 millimeters diameter in critical leg ischemia

OBJECTIVE The purpose of this study was to evaluate the difference in amputation-free survival and patency rates of infra-inguinal bypass grafts in patients with critical leg ischemia (CLI) with vein conduits with an internal diameter <3 mm compared to those with vein conduits with a diameter of ≥ 3 mm. METHODS Retrospective analysis of all consecutive patients with CLI undergoing infra-inguinal bypass. Preoperative duplex scan mapping and measurement of potential vein grafts were performed on all patients. Patients were recruited in a 1-year duplex scan graft surveillance program. Primary end points were amputation-free survival and patency rates at 1 year postoperatively. Kaplan-Meier and χ(2) test were used for statistical analysis. RESULTS Between January 2004 and April 2010, 157 consecutive patients with CLI underwent 171 bypasses using vein conduits (111 men, 46 women; median age, 75 years; range, 45-96 years). Ninety-three bypasses (54.4%) were performed for tissue loss, 44 (25.7%) for gangrene, and for rest pain. Of the 157 patients, 113 (72.0%) had diabetes mellitus, 40 (25.5%) had renal impairment, 131 (83.4%) had hypertension, and 64 (40.8%) had ischemic heart disease. Femoro-popliteal bypass was performed in 38 cases (22.2%), whereas 133 (77.8%) of the bypasses were femoro-distal. Autogenous great saphenous vein (GSV) was used in all cases. All grafts were reversed. The diameter of 31 (18%) vein conduits measured <3 mm (range, 2-2.9 mm) on preoperative duplex scan. One hundred thirty-four grafts had at least 1-year follow-up. The primary, assisted primary, and secondary patency rates at 1 year for vein conduits <3 mm were 51.2%, 82.6%, and 82.6%, respectively, compared to 68.4%, 93.3%, and 95.2%, respectively, in the ≥ 3 mm group. This was only significant for the secondary patency (P = .0392). The amputation-free survival at 48 months was 70.8% for vein conduits <3 mm and 57.3 for vein conduits ≥ 3 mm. CONCLUSION This series has shown that primary and assisted primary patency rates in small veins are not significantly different at 1 year but the secondary patency rates are better in the larger veins. Similarly, the amputation-free survival was also comparable. The authors would, therefore, advocate the use of small veins >2 mm in diameter in patients with CLI. Duplex scan surveillance followed by early salvage angioplasty for threatened grafts is needed to achieve good patency rates in both groups.

Transformation of the Multidisciplinary Diabetic Foot Clinic Into a Multidisciplinary Diabetic Foot Day Unit Results From a Service Evaluation

The natural history of the diabetic foot is aggressive and complex. To counteract this, we describe the transformation of a Multidisciplinary Diabetic Foot Clinic into a Multidisciplinary Diabetic Foot Day Unit, which delivers an emergency open access system for patients, with a “one-stop,” same day service in which investigations are performed, results reviewed and treatment implemented. It also provides joint clinics with vascular, orthopaedic, and plastic surgeons and specialized clinics for casting of complex neuropathic feet and for the administration of intravenous or intramuscular antibiotics on the same day. The aim was to document these increasingly wide-ranging facilities by undertaking a retrospective evaluation over a 6-week period, with analysis of notes, investigations, and an anonymous patient satisfaction survey. The clinic was visited by 597 patients who attended in 1076 appointments, of which 112 (10.4%) were emergency visits; these patients attended the clinic without a booked appointment but via an open access policy, 93 of whom were known to the clinic, but 19 were new self-referred patients to the service. Furthermore, 197 (18%) were seen in a Joint Vascular Diabetic Foot Clinic and 98 (9%) were seen in a Joint Orthopaedic Plastic Diabetic Foot Clinic, 570 (53%) were seen in an Active Ulcer Clinic and 97 (9%) in a Total Contact Casting Clinic. Forty-five percent of patients were prescribed antibiotics, including 188 (76%) as oral and 45(18%) as intravenous antibiotics and 15(6%) as intramuscular injections. Of the 1076 appointments, 150 (14%) patients were in the foot clinic for more than 4 hours. Sixty (10%) patients were reviewed 4 or more times over the 6-week period. Only 22 (2%) were admitted to hospital. Of the 125 survey responders, 98% were satisfied with this service, which has evolved from a Diabetic Foot Clinic into a Multidisciplinary Diabetic Foot Day Unit.

Case Report: Microbubble Contrast-Enhanced Ultrasound Characteristics of Multiple Biliary Hamartomas (von Meyenberg Complexes)

Multiple biliary hamartomas (von Meyenberg complexes) are an uncommon benign biliary neoplasm detected incidentally on imaging. To our knowledge the appearances of multiple biliary hamartomas on microbubble contrast-enhanced ultrasound have not been previously described. We report a case using Coherent Contrast Imaging® and Agent Detection Imaging® techniques with the contrast agents Sonovue®and Levovist®. While both methodologies failed to differentiate these focal liver lesions from malignant neoplasms, they enhanced the conspicuity of the hamartomas. Radiologically-guided biopsy and histological analysis remain the reference standard in the diagnosis of multiple biliary hamartomas.

Multimodal intraoperative monitoring: An observational case series in high risk patients undergoing major peripheral vascular surgery

Recent guidelines from the National Institute of Health and Care Excellence (NICE) and the UK National Health Service (NHS) have stipulated that intraoperative flow monitoring should be used in high-risk patients undergoing major surgery to improve outcomes and reduce costs. Depth of anaesthesia monitoring is also recommended for patients where excessive anaesthetic depth is poorly tolerated, along with cerebral oximetry in patients with proximal femoral fractures. The aims of this descriptive case series were to evaluate the impact of a multimodal intraoperative strategy and its effect on mortality and amputation rate for patients with critical leg ischaemia. In an observational case series, 120 elderly patients undergoing major infra-inguinal bypass between 2007 and 2012 were included in this retrospective analysis of prospectively collected data. Nominal cardiac output (nCO, LiDCOrapid, LiDCO Ltd, UK), bispectral index to monitor depth of anaesthesia (BIS, Covidien, USA) and cerebral oxygenation, rSO2 (Invos, Covidien, USA) readings were obtained before induction of general anaesthesia and throughout surgery. 30 day, 1-year mortality and amputation rates were analysed. Demographics and physiological parameters including correlation with V-POSSUM, age, gender and other co-morbidities were statistically analysed. Thirty-day mortality rate was 0.8% (n = 1). V-POSSUM scoring indicated a predicted mortality of 9%. Amputation rate was less than 2% at one year. Only 8% of patients (10 of 120) were admitted to a high dependency unit (HDU) postoperatively. 30-day mortality in our case series was lower than predicted by V-POSSUM scoring. Use of multimodal intraoperative monitoring with the specific aim of limiting build-up of oxygen debt should be subjected to a randomised controlled study to assess the reproducibility of these results.

Occult carotid artery disease in patients who have undergone coronary angioplasty.

OBJECTIVES The aim was to evaluate the prevalence of asymptomatic mild (30-49%), moderate (50-69%) and severe (70-99%) ICA stenosis in patients who underwent previous coronary angioplasty (PTA). METHODS After obtaining ethics committee approval, 144 consecutive patients aged between 65 and 75 years were invited for carotid Duplex evaluation with a linear 6 MHz array transducer by trained vascular sonographers within a single unit. A peak systolic velocity >230 cm/s in the ICA was considered as significant (>70% stenosis). RESULTS Of the 144 patients approached, 117 (81%) attended (male:female ratio 3.2:1, age range 65-75 years, median age 71 years). Duplex ultrasound revealed one occlusion, 70% or more ICA stenosis in three patients (2.6%), 50-69% stenosis in 12 patients (10.3%) and 30-49% stenosis in 29 patients (24.8%). CONCLUSIONS Carotid artery disease with a luminal stenosis of 30% or more is common in patients who underwent previous PTA. The yield of significant ICA stenosis (70% or more), which would benefit from carotid endarterectomy according to the Asymptomatic Carotid Surgery Trial is low. Recommendation for initial screening and subsequent follow-up Duplex examination for evaluation of disease progression of such cohorts remains debatable.