Short term physiological changes secondary to exercise in intermittent claudication : short term physiological changes in claudication

Background: In patients with intermittent claudication (IC), supervised exercise programmes (SEP) improve walking distance and quality of life (QoL); however the mechanisms by which these benefits are achieved remain unclear.Endothelial dysfunction is recognised as a trigger of the atheroinflammatory cascade and subsequent cardiovascular disease. In health, training improves cardiorespiratory physiology, inflammation and endothelial function. Changes in cardiorespiratory physiology, inflammatory markers and endothelial function are contradictory in IC.Objectives: This thesis aimed to assess the impact of SEP on cardiopulmonary physiology, endothelial function and athero-inflammatory markers in patients with IC.Methods: Following local research ethics committee and R & D approval, patients with IC were recruited from outpatient clinic. After providing informed written consent, patients underwent baseline assessment on two separate days.Session 1: participants completed a constant load treadmill test with pre and post exercise ankle brachial pressure indices.Session 2: measured QoL, endothelial function (EndoPAT2000, Itamar, Israel), venepuncture and a cardiopulmonary exercise test (CPET) using cycle ergometry. Participants then underwent a 12 week period of SEP which consisted of circuit training, with re-assessments at six and twelve weeks. The primary outcome measure was a 1.5ml/kg/min improvement in peak VO₂ after six weeks of exercise. Secondary outcomes included changes in endothelial function, quality of life, walking distance and inflammatory markers at both six and twelve weeks.Results: No significant improvements in CPET measurements, endothelial function or inflammation were demonstrated at any time point. Traditional markers of walking ability and QoL demonstrated an improvement by 12 weeks.Conclusions: The underlying mechanism through which exercise improves walking distance remains un-identified. Further work regarding the changes at the cellular level within the muscle is of importance

Percutaneous transluminal angioplasty results in improved physical function but not balance in patients with intermittent claudication

Objective The aim of this study was to identify whether revascularization by percutaneous transluminal angioplasty (PTA) for patients with intermittent claudication improved measures of functional performance including balance. Methods A prospective observational study was performed at a single tertiary vascular center. Patients with symptomatic intermittent claudication (Rutherford grades 1-3) were recruited to the study. Participants were assessed at baseline (pre-PTA) and then 3, 6, and 12 months post-PTA for markers of (1) lower limb ischemia (treadmill walking distances and ankle-brachial pressure index), (2) physical function (6-minute walk, Timed Up and Go, and chair stand time), (3) balance impairment using computerized dynamic posturography with the Sensory Organization Test, and (4) quality of life (VascuQoL and Short Form Health Survey [SF-36]). Results Forty-three participants underwent PTA. Over 12 months, a significant improvement was demonstrated in initial (P = .04) and maximum treadmill walking distance (P = .019). Physical functional ability improved across all outcome measures (P < .02), and some domains of both generic (P < .03) and disease-specific quality of life (P < .01). No significant improvement in balance was demonstrated by the Sensory Organization Test (P = .24). Conclusions Balance impairment is common in claudicants and does not improve with revascularization. Further research regarding effective treatment of balance impairment is required in this specific group of patients

Factors affecting the patency of arteriovenous fistulas for dialysis access

BackgroundThe autologous arteriovenous fistula (AVF) is the accepted gold standard mode of repeated vascular access for hemodialysis in terms of access longevity, patient morbidity, and health care costs. This review assesses the current evidence supporting the role of various patient and surgeon factors on AVF patency.MethodsThe literature was searched to identify the current evidence available for patient characteristics, methods of AVF planning, and anatomic factors that may affect patency outcomes after AVF formation. The use of adjuvant medications, surgical techniques, and policies for AVF maintenance are discussed in relation to AVF patency.ResultsCurrent literature supports patient factors, such as increasing age, presence of diabetes, smoking, peripheral vascular disease, predialysis hypotension, and vessel characteristics, as directly influencing AVF patency. Vessels of small caliber (<2 mm) or demonstrating reduced distensibility are unlikely to create a functional AVF. Current evidence does not support altered patency due to sex or raised body mass index (<35 kg/m2). Factors such as early referral for AVF, preoperative ultrasound vessel mapping, use of vascular staples, and intraoperative flow measurements affected AVF patency, but the use of medical adjuvant therapies did not. Programs of surveillance and various needling techniques to maintain patency are not supported by current evidence. Novel techniques of infrared radiotherapy and topical glyceryl trinitrate are possible future strategies to increase AVF patency rates. The limitations of available evidence include a lack of large, randomized controlled trials and meta-analysis data to support current practice.ConclusionsThere is a complex interaction of factors that may affect the patency of an individual AVF. These need to be carefully considered when selecting surgical site or technique, adjuvant treatments, and follow-up protocols for AVFs

Electrical stimulation vs. standard care for chronic ulcer healing: a systematic review and meta-analysis of randomised controlled trials

BackgroundWe conducted a systematic review to investigate the effect of electrical stimulation on ulcer healing compared to usual treatment and/or sham stimulation. This systematic review also aimed to investigate the effect of different types of electrical stimulation on ulcer size reduction.Materials and MethodsMEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to October 2013 on randomised controlled trials (RCTs), in English and on human subjects, which assessed the effect of electrical stimulation on ulcer size as compared to standard care and/or sham stimulation. Data from included RCTs were pooled with use of fixed and random effects meta-analysis of the weighted mean change differences between the comparator groups. Heterogeneity across studies was assessed with the I2 statistic.ResultsTwenty-one studies were eligible for inclusion in the meta-analysis. In six trials (n = 210), electrical stimulation improved mean percentage change in ulcer size over total studies periods by 24·62%, 95% confidence interval (CI) 19·98–29·27, P < 0·00001 with no heterogeneity. In three trials (n = 176), electrical stimulation insignificantly improved mean weekly change in ulcer size by 1·64%, 95% (CI) −3·81 to 7·09, P = 0·56 with significant heterogeneity (I2 = 96%, P < 0·00001). In six trials (n = 266), electrical stimulation decreased ulcer size by 2·42 cm2, 95% (CI) 1·66–3·17, P < 0·00001, with significant heterogeneity. In one trial (n = 16), electrical stimulation also insignificantly improved the mean daily percentage change in ulcer size by 0·63%, 95% (CI) −0·12 to 1·37, P = 0·10, with significant heterogeneity.ConclusionsElectrical stimulation appears to increase the rate of ulcer healing and may be superior to standard care for ulcer treatment

A comparison of the effectiveness of treating those with and without the complications of superficial venous insufficiency

Objective: To test the hypothesis that patients with soft tissue changes related to superficial venous insufficiency (SVI) have greater benefits from treatment than those with only symptomatic varicose veins.Background: A commonly held view is that SVI is only a minor ailment, yet randomized clinical trials (RCTs) show that treatment improves quality of life (QoL) and is cost-effective. In an effort to curb the treatment costs of this common disorder, rationing is applied in many health care systems, often limiting the reimbursement of treatment to those with soft tissue changes.Methods: This cohort study draws its data from an interventional RCT. After informed consent, consecutive patients with symptomatic unilateral SVI were randomized to receive surgical ligation and stripping or endovenous laser ablation. This analysis differentially studies the outcomes of patients with simple varicose veins (C2: n = 191) and soft tissue complications (C3-4: n = 76). Effectiveness outcomes measured up to 1 year included the following: Qol [short form 36 (SF36), EuroQol, and the Aberdeen Varicose Veins Questionnaire], clinical recurrence, and the need for secondary procedures. Multivariable regression analysis was used to control for potential confounding factors.Results: Both groups saw significant improvements in QoL. All improvements were equal between groups apart from the SF36 domain of Bodily Pain, where C2 saw an improvement of 12.8 [95% confidence interval (CI): 4.8-20.8] points over C3-4 participants (P = 0.002), who also suffered more recurrence [odds ratio (OR) = 2.7, 95% CI: 1.2-6.1, P = 0.022] and required more secondary procedures (OR = 4.4, 95% CI: 1.2-16.3, P = 0.028).Conclusions: This study suggests that rationing by clinical severity contradicts the evidence. Delaying treatment until the development of skin damage leads to a degree of irreversible morbidity and greater recurrence

Computerized dynamic posturography for postural control assessment in patients with intermittent claudication.

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic conditions. As part of a diagnostic assessment, the early detection of postural deficits is important so that appropriate and targeted interventions can be prescribed. The Sensory Organization Test (SOT) on the EquiTest determines an individual's use of the sensory systems (somatosensory, visual, and vestibular) that are responsible for postural control. Somatosensory and visual input are altered by the calibrated sway-referenced support surface and visual surround, which move in the anterior-posterior direction in response to the individual's postural sway. This creates a conflicting sensory experience. The Motor Control Test (MCT) challenges postural control by creating unexpected postural disturbances in the form of backwards and forwards translations. The translations are graded in magnitude and the time to recover from the perturbation is computed. Intermittent claudication, the most common symptom of peripheral arterial disease, is characterized by a cramping pain in the lower limbs and caused by muscle ischemia secondary to reduced blood flow to working muscles during physical exertion. Claudicants often display poor balance, making them susceptible to falls and activity avoidance. The Ankle Brachial Pressure Index (ABPI) is a noninvasive method for indicating the presence of peripheral arterial disease and intermittent claudication, a common symptom in the lower extremities. ABPI is measured as the highest systolic pressure from either the dorsalis pedis or posterior tibial artery divided by the highest brachial artery systolic pressure from either arm. This paper will focus on the use of computerized dynamic posturography in the assessment of balance in claudicants

Balance impairment, physical ability, and its link with disease severity in patients with intermittent claudication

BackgroundTo determine whether increasing claudication severity is associated with impaired balance and physical functional ability.MethodsA prospective observational study in claudicants was performed. Disease severity was determined according to Rutherford's criteria. Patient's balance was assessed objectively using computerized dynamic posturography (CDP-Sensory Organization Test [SOT]; NeuroCom). "Bedside" assessment of balance was performed using the Timed Up and Go (TUG) test (dynamic balance) and the Full Tandem Stance test (static balance). Physical function was assessed using the Summary Physical Performance Battery (SPPB) score.Results185 claudicants were assessed (median age of 69 [IQR 63-74] years; 137 [74.1%] men). Fourteen claudicants were classified as Rutherford grade 0, 26 as grade I, 76 as grade II, and 69 as grade III. All Rutherford groups were comparable for age, gender, BMI, and comorbidities.Increasing Rutherford grade was associated with a significant deterioration in objective balance as determined by a failed SOT test: 3 (21.4%) in grade 0; 9 (34.6%) in grade I; 39 (52.7%) in grade II; and 41 (59.4%) in grade III (chi-squared 9.693, df 3, P = 0.021). A significant difference was also found with dynamic balance (TUG test), but not static balance (full tandem stance).Increasing claudication severity was also associated with significantly worse physical function: SPPB score.ConclusionsSpecific objective tests demonstrate impaired balance and physical function are common in claudicants and become more frequent with increasing severity of claudication. Simple "bedside" measures may be sufficiently sensitive to detect this