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R C Kester

Publications and source records attributed to R C Kester.

At least 19 recordsLinked to original sources

Does angioplasty improve the quality of life for claudicants?: A prospective study.

This study aims to analyze the impact of percutaneous transluminal angioplasty (PTA) for claudication on patients' quality of life (QOL). The patients in this study included 108 claudicants, 74 men and 34 women, with a median age of 67 years (range 40-87 years), who were assessed prior to and at 1, 3, and 6 months following PTA. This is the first report to demonstrate that the previously well-documented improvements in the clinical indicators of lower-limb ischemia are accompanied by improvements in individual QOL domains and in overall global QOL. These findings are detectable within a month following PTA and last at least 6 months. The results of this study may go some way to provide proof of efficacy for the procedure and thus help justify the recently questioned widespread use of PTA in clinical practice.

Aged

A comparison of teicoplanin versus cephradine plus metronidazole in the prophylaxis of post-operative infection in vascular surgery.

A total of 272 patients were enrolled into this prospective, unblinded, randomized comparison of single-dose teicoplanin vs three doses of cephradine plus metronidazole as prophylaxis for vascular surgery at St James's and Seacroft Hospitals, Leeds, UK. In all, 71.3% of patients (194/272) were enrolled at St James's University Hospital. Patients received either a single dose of teicoplanin, 6 mg/kg i.v., or cephradine, 1 g i.v. with metronidazole, 1 g rectally, at induction of anaesthesia followed by two further 1 g doses of cephradine and metronidazole 8 and 16 hours later. There were 136 patients in each treatment group. The most common operations were femoropopliteal grafts (96) and aortic aneurysm repairs (47). In the 'intention-to-treat' analysis, primary wound infections were seen in 4.4% of patients (6/136) receiving teicoplanin and 5.9% of patients (8/136) receiving cephradine plus metronidazole (95% CI -6.7%, +3.8%). Other disturbances to wound healing occurred in 23 patients (11 in the teicoplanin and 12 in the cephradine plus metronidazole group). Secondary respiratory tract infections occurred in 17 patients (8 receiving teicoplanin and 9 receiving cephradine plus metronidazole). In the evaluable patients analysis, primary wound infections occurred in 3.5% of patients (4/114) receiving teicoplanin and 5.1% of patients (6/117) receiving cephradine plus metronidazole. Staphylococcus aureus and Proteus sp. were the most common pathogens in primary wound infections. Despite the absence of Gram-negative cover in the teicoplanin group, Gram-negative infections occurred more often in the cephradine plus metronidazole group. Surgery of the lower extremities carried the highest risk of post-operative infection. Rates of infection were significantly higher at Seacroft Hospital (P = 0.001), and significantly higher for cephradine plus metronidazole between the two hospitals (P = 0.0008). Adverse events occurred in 40 patients receiving teicoplanin (29.4%) and 39 patients receiving cephradine plus metronidazole (28.7%). In 19 patients receiving teicoplanin (14%) and 15 receiving cephradine plus metronidazole (11%) these events were considered to be related to the study drugs. The most often reported events were infections, cardiac events and vascular phenomena (haematoma or emboli). Marked changes in haematological parameters and liver function tests were noted seven days after operation in patients in each treatment group, but these resolved quickly as the effects of the operation subsided. ESR remained elevated in both groups at the six-month follow-up assessment. It is concluded from this two-centre study that a single dose of teicoplanin shows similar efficacy to a three-dose regimen of cephradine plus metronidazole as prophylaxis for wound infection in vascular surgery. Both regimens were well tolerated, and there was an equal incidence of adverse events in the two regimens, which reflected the poor general health status of this elderly study population.

Adolescent

Does soluble intercellular adhesion molecule-1 (ICAM-1) affect neutrophil activation and adhesion following ischaemia-reperfusion?

OBJECTIVES: To examine the effect of reperfusion plasma and sICAM-1 on neutrophil integrin expression and neutrophil adhesion to determine if sICAM-1 has a potential role in the regulation of neutrophil adhesion. MATERIALS: Twenty-seven patients, 17 men and 10 women undergoing femorodistal surgery. Blood was taken preoperatively and from the femoral vein following the release of the cross-clamp. Neutrophils were obtained from five volunteers and incubated with phosphate buffered saline (PBS), preoperative plasma or reperfusion plasma with and without sICAM-1. Neutrophil expression of CD11b and adhesion were measured. MAIN RESULTS: Neutrophil CD11b expression did not change following incubation in the three media. Neutrophil adhesion increased significantly following exposure to reperfusion plasma compared to PBS or preoperative plasma (45.5 adhesion vs. 12.75%, p < 0.01 Mann-Whitney U-test). Soluble ICAM-1 decreased CD11b expression and adhesion in neutrophils exposed to reperfusion plasma only (CD11b expression fell from 15.9 to 3.4 mcf, p < 0.01 Mann-Whitney U-test and adhesion fell to 11.6% cells adhered, p < 0.01). CONCLUSION: An increase in CD11b expression is not required for an increase in neutrophil adhesion. The change in neutrophil adhesion produced by reperfusion plasma can be blocked by sICAM-1. Soluble ICAM-1 may have a physiological role in the regulation of neutrophil adhesion.

Aged

Duplex-derived evidence of reflux after varicose vein surgery: neoreflux or neovascularisation?

BACKGROUND: Recurrent varicose veins remain a problem in surgical practice despite improvements to the preoperative investigation of, and surgery for varicose veins. Neovascularisation accounts for some cases of recurrence within a few years of surgery, but other factors relating to disease progression must also play a part. We investigated whether new venous reflux (neoreflux) could occur in the early postoperative period (within 6 weeks) following successful varicose vein surgery. METHODS: Eighteen-month prospective observational study in the dedicated vascular surgery unit of a university teaching hospital. Forty-six patients, with primary saphenofemoral junction reflux, awaiting varicose vein surgery were chosen consecutively from the waiting list. All saphenofemoral surgery was performed in a standardised fashion. Assessments were performed prior to, at 6 weeks and at 1 year after surgery. Duplex ultrasound was used to identify and locate sites of reflux. RESULTS: Neoreflux was present at the 6-week postoperative scan in nine limbs after varicose vein surgery (19.6%), and resolved in 55.6% of patients within 1 year. Neovascularisation was noted in two limbs at the 1-year scan. CONCLUSION: New sites of reflux, which may resolve spontaneously, occur in the early postoperative period despite adequate varicose vein surgery. It is our hypothesis that this is a manifestation of the effect of altered venous haemodynamics in a system of susceptible veins.

Adult

The hand arm vibration syndrome: a review.

Since its first description over eight decades ago, the hand arm vibration syndrome-- vibration white finger as it was previously known--has become one of the most common prescribed diseases in the industrialized world. This article is intended to provide a broad review of existing evidence and knowledge regarding a disease which, for medicolegal reasons, demands attention from all medical personnel. Detailed discussion is presented regarding: the multifactorial aetiology of the syndrome; suggestions for clinical assessment, laboratory investigations and classification of disease severity; and strategies for the prevention and treatment of the syndrome.

Fingers

The aetiology of Raynaud's phenomenon.

The literature on Raynaud's phenomenon (RP) describes a complex and confusing picture of abnormalities that has suggested a multifactorial aetiology. Current research suggests that the underlying disorder is related to a local fault at the level of the digital microcirculation. It is likely that many of the biological changes described in RP are secondary manifestations of this primary abnormality. The strong familial relationship of RP suggests a genetic link although this has not yet been characterized. An overactivity of the sympathetic nervous system appears less likely as a candidate for the primary abnormality and dysfunction at the level of the nerve, and vessel wall may be more important. Digital cutaneous neurones show a deficient release of the vasodilatory calcitonin gene related peptide in PR. This may represent a primary fault that is confounded by other factors, which are influenced by cold or emotional triggers. Vasoconstricting substances such as catecholamines, endothelin-1 and 5-hydroxytryptamine, which may all be released in response to cold exposure, could cause digital artery closure and the associated symptoms of RP. In some cases, this would trigger a cascade of neutrophil and platelet activation, which through the release of inflammatory mediators, contribute to the endothelial damage seen with more severe RP. It is hypothesised that disturbance to the intricate functioning of the endothelium, and secondary compensation at local or systemic level, may appear over time. There is, therefore, still a need to differentiate the true aetiological factors from those that are causal associations with Raynaud's phenomenon. Progress is slowly being made with better understanding of the intricacies between these factors and the microcirculation. Deepening our comprehension of the 'normal' mechanisms that influence microvascular blood flow is necessary to develop a better understanding of the pathophysiology of Raynaud's phenomenon.

Blood Platelets

Exercise-induced neutrophil activation in claudicants: a physiological or pathological response to exhaustive exercise?

OBJECTIVES: To assess the effect of exhaustive exercise on neutrophil activation and degranulation in claudicants and controls. We investigated the hypothesis that neutrophil activation and degranulation are normal responses to exhaustive exercise in healthy patients. DESIGN: This was a controlled experimental two-group study. MATERIALS: Exercise was performed using a fixed workload treadmill test. Neutrophil activation was assessed by flow cytometry of whole blood labelled with anti-CD11b mouse IgG, and neutrophil degranulation in terms of plasma elastase measured by enzyme-linked immunosorbent assay. METHODS: Twenty-eight claudicants with stage 1 chronic leg ischaemia, and 22 healthy controls were recruited. Blood and urine samples were collected before and after treadmill exercise. Claudicants exercised to their maximum walking distance, and controls at a higher "fatigue" workload for a maximum of 20 min. RESULTS: Exercise produced a brief but significant neutrophilia in both groups. Neutrophil CD11b expression increased significantly after exercise only in the claudicants, and was associated with a significant rise in plasma neutrophil elastase. These indices remained unchanged in the control group at all time points despite exercise at a fatigue level. CONCLUSION: The inflammatory response associated with exercise in claudicants is not simply a physiological response to exhaustive exercise.

Aged

Percutaneous transluminal angioplasty for intermittent claudication: evidence on which to base the medicine.

OBJECTIVES: This study aims to assess the impact of PTA on the quality of life (QoL) of claudicants and to analyse which patients and which arterial lesions derive the most benefit. DESIGN: A prospective observational study. MATERIALS: One hundred and seventeen claudicants undergoing PTA were studied; 35 patients had bilateral disease, whilst 82 had unilateral disease and underwent PTA to a solitary iliac lesion, solitary superficial femoral or a iliac lesion above a diseased superficial femoral artery in 24, 39 and 19 cases, respectively. METHODS: Patients completed the Short Form 36 (SF36) and EuroQol (EQ) QoL assessment instruments prior to and at 1, 3, 6, and 12 months following intervention. The SF36 produces a QoL profile, whilst the EQ produces two QoL indices. RESULTS: Claudication has a deleterious effect on QoL, especially in patients with multi-segment disease. PTA results in an immediate and lasting improvement in the QoL of claudicants. Unilateral claudicants undergoing PTA to a solitary iliac lesion demonstrate the most marked QoL benefits and 12 months post PTA report a QoL approaching that of an age-matched population. Patients with bilateral claudication undergoing unilateral PTA and unilateral claudicants undergoing PTA to a solitary SFA lesion demonstrate some QoL benefits, but at 12 months post PTA do not approach the QoL scores of an age-matched population. Unilateral claudicants undergoing iliac PTA above a diseased SFA demonstrate minimal QoL changes. CONCLUSIONS: These results should influence decision making in the management of claudication and it may be possible to prioritise PTA waiting lists to ensure patients with greatest potential benefit are treated with most urgency.

Adult

Reduced total antioxidant capacity predicts ischaemia-reperfusion injury after femorodistal bypass.

BACKGROUND: Antioxidant defence systems are essential to protect the body from harmful free radicals released following ischaemia-reperfusion. The aim of this study was to examine the total antioxidant capacity (TAC) of patients with chronic critical leg ischaemia undergoing femorodistal bypass and to correlate this with lipid peroxidation, changes in capillary permeability and clinical outcome. METHODS: Twenty-five patients, 15 men and ten women of median age 71 (range 62-79) years, and 15 matched controls were studied. Blood was taken before operation and after reperfusion, with assays performed for malondialdehyde (a product of lipid peroxidation) and total antioxidant capacity. Changes in capillary permeability were measured by changes in the urinary albumin:creatinine ratio (ACR) following reperfusion of the ischaemic leg and expressed as a percentage increase from the preoperative value. Clinical outcome in terms of the systemic inflammatory response syndrome (SIRS) was recorded. RESULTS: Vascular patients who developed clinical evidence of a systemic inflammatory reaction following revascularization had a significantly reduced TAC compared with the controls (490 versus 860 mumol/l; P < 0.01, Mann-Whitney U test). These patients also demonstrated an increase in lipid peroxidation (0.5 versus 0.25 mumol/l, P < 0.05) and vascular permeability, as measured by the percentage increase in ACR (365 versus 130 per cent, P < 0.01). CONCLUSION: Vascular patients with a lower TAC developed increased capillary permeability as a result of ischaemia-reperfusion, which progressed to SIRS. TAC may provide a test to identify 'at risk' patients. It may be possible to augment their defence with exogenous antioxidants.

Aged

Comparison of POSSUM and the Portsmouth predictor equation for predicting death following vascular surgery.

BACKGROUND: The Physiological and Operative Severity Score for enUmeration of Mortality and morbidity (POSSUM) scoring system has been proposed as an accurate predictor of death which takes account of case mix. It appears to overpredict death, and may have drawbacks which prevent accurate individual or subgroup analysis. An alternative system, the Portsmouth predictor equation for mortality (P-POSSUM) may have overcome these problems, but its apparent advantage could be related to inappropriate analysis of POSSUM predictions. METHODS: Some 312 patients having arterial procedures were studied. POSSUM and P-POSSUM scores were used to predict death and compared with actual outcomes. The observed:predicted (O:E) mortality ratios were calculated by two methods for each of the scoring systems. First the analysis devised by the inventors of POSSUM was used and second the method devised for P-POSSUM. RESULTS: The O:E ratio for POSSUM using its recommended 'exponential' method of analysis was 1.14, but it was 0.59 if the P-POSSUM 'linear' analysis was used. The O:E ratio for P-POSSUM using its correct method of analysis was 0.89, but it was 0.67 if the method of analysis devised for POSSUM was used. CONCLUSION: The O:E ratios for POSSUM and P-POSSUM were close to unity when the appropriate analysis was performed. Both POSSUM and P-POSSUM overpredicted death if the incorrect analysis was used.

Aged

Prospective analysis of quality of life in patients following infrainguinal reconstruction for chronic critical ischaemia.

BACKGROUND: The aims of this prospective study were to analyse the health-related quality of life (QOL) changes associated with infrainguinal arterial reconstruction for chronic critical limb ischaemia (CLI) and to assess the impact of graft patency and limb salvage. METHODS: Fifty-five consecutive patients, 28 women and 27 men of median age 71 (range 41-86) years, undergoing infrainguinal arterial reconstruction for CLI, consented to participate in the study. QOL was assessed using the Short Form 36 (SF36) health survey questionnaire, which was completed before and at 1, 3, 6 and 12 months following surgery. Graft patency was assessed by duplex imaging at the same postoperative intervals. RESULTS: CLI severely impaired QOL. Cumulative graft patency at 1, 3, 6 and 12 months after surgery was 82, 78, 76 and 64 per cent respectively. Reconstruction resulted in significant improvements in the SF36 domains Physical Functioning, Pain, Vitality and Social Functioning (P< 0.01). With a patent graft these improvements began soon after surgery and were maintained for the 12 months studied. Following irredeemable graft occlusion, patients who had secondary amputation also described some QOL improvements. CONCLUSION: A patent graft following infrainguinal arterial reconstruction for critical ischaemia results in an immediate and lasting improvement in health-related QOL.

Activities of Daily Living

The role of leukocytes in the pathogenesis of vibration-induced white finger.

Vibration white finger (VWF) is an occupational disorder associated with long-term exposure to hand-transmitted vibration. The condition exhibits features of secondary Raynaud's phenomenon. The etiology is unknown. The aim of this study was to examine the role of leukocyte rheology in the pathogenesis of VWF. Fifty-two male subjects divided into two groups were exposed to controlled acute hand-transmitted vibration. One group consisted of 29 workers who have all had occupational exposure to handheld vibration and all suffered from VWF (mean age 46.9 years, range 22-66). The second group consisted of 23 controls. Venous blood was analyzed from the dorsum of the hand before and after vibration to determine granulocyte deformability, granulocyte morphology, and white blood cell count with differential. There was a subpopulation of hard and poorly deformable granulocytes in the VWF group when compared with controls (p < 0.05). Acute hand-transmitted vibration had no in vitro effect on leukocyte rheology in either group. Leukocyte rheology may play a role in the pathogenesis of microvascular disease and tissue ischemia in VWF, although whether this is a cause or an effect of the disorder is not clear.

Adult

Five years' experience of PAS Port intravenous access system in adult cystic fibrosis.

An implantable venous access system provides a reliable and painless entry site for intravenous treatment. This study reports the authors' experience with such a system in adult patients with cystic fibrosis. Sixty five (87%) of 75 PAS Ports were placed successfully in 57 patients with cystic fibrosis. Because of early difficulties in advancing the catheter in patients whose veins had been traumatized by repeated courses of intravenous antibiotics, a technique was developed whereby venous entry was gained by direct subclavian puncture. This catheter insertion method was used in 53 (82%) attempts and the catheter was then passed by subcutaneous tunnelling to the port site on the ventral aspect of the upper arm. Fifty seven (88%) insertions were successful under local anaesthetic. The major early and late complications were iatrogenic pneumothorax (six cases) and infection (five cases), respectively. Late complications were more common when there was coexisting disease, e.g. diabetes mellitus, or an acute severe respiratory exacerbation, or when the Port was used for parenteral feeding. In conclusion, the PAS Port can be inserted safely by direct subclavian puncture. It was well tolerated and universally liked by the patients.

Adult

Randomized, double-blind, placebo-controlled study evaluating the efficacy and safety of AS-013, a prostaglandin E1 prodrug, in patients with intermittent claudication.

BACKGROUND: Intermittent claudication due to peripheral arterial occlusive disease (PAOD) is a common cause of pain and disability in the middle-aged. Clinical trials of the potent vasodilator prostaglandin E1 have been disappointing. This is the first report of a controlled clinical trial of AS-0:3, a novel prodrug of prostaglandin E1 incorporated into lipid microspheres that has been developed to improve delivery of the active compound to blood vessel walls. METHODS AND RESULTS: Eighty patients with stenosis or occlusion, symptoms of intermittent claudication, and maximum walking distance of > or = 30 and < or = 300 m on a standard treadmill test were randomized to placebo or one of three dosage regimens of AS-013. Drug was administered by intravenous injection 5 d/wk for 4 weeks. Treadmill tests and other assessments were completed at weeks 0, 4, and 8. A statistically significant increase in maximum walking distance was observed at 4 weeks (for placebo: median, 4.5 m; interquartile range [IQR], 20; for active treatment: median, 28.0 m; IQR, 81; P < .01, Mann-Whitney test). A similar response was seen at 8 weeks (for placebo; median, -11.2 m; IQR, 35; for active treatment: median, 35 m; IQR, 68; P < .01, Mann-Whitney test). Dose-related improvements in pain-free walking distance and quality of life were observed. No serious safety issues were noted. CONCLUSIONS: These promising clinical data indicate that AS-013, a new prodrug of prostaglandin E1, could provide an effective and acceptable treatment for patients with intermittent claudication. Studies to investigate the optimal dosing regimen, duration of clinical benefit, and effects in more severe forms of peripheral arterial disease are warranted.

Aged

Correlating clinical indicators of lower-limb ischaemia with quality of life.

The objectives of the study were to analyse the impact of increasing lower-limb ischaemia upon quality of life and to assess the correlation between clinical indicators of lower-limb ischaemia and such quality. A prospective observational study of a consecutive series of 235 patients (144 men and 91 women; median age 68 (range 41-87) years presenting with varying degrees of lower-limb ischaemia graded according to ISCVS criteria was performed. Data was collected at interview before any intervention. Clinical indicators of lower-limb perfusion included: intermittent claudication and maximum walking distance on standardized treadmill testing; ankle:brachial pressure indices and isotope limb blood flow. Quality of life analysis was performed using the EuroQol (EQ) questionnaire. This is a standardized generic instrument for describing health-related quality of life and consists of a descriptive system of five dimensions, each measured on three levels. Thus, a profile and two single indices of quality of life were derived using different methods. Increasing lower-limb ischaemia results in a statistically significant deterioration in both global quality of life and in all EQ-measured quality of life dimensions (P < 0.01 Kruskal-Wallis, ANOVA). The correlation between clinical indicators and quality of life is statistically significant but not sufficiently close (correlation coefficients < 0.6) to assume that variations in clinical indicators result in reciprocal variations in quality of life. In conclusion, as might be expected, a significant correlation exists between clinical indicators of lower-limb ischaemia and health-related quality of life. However, the low correlation coefficients emphasize how tenuous the association is. Thus, a significant improvement in the clinical indicators of lower-limb ischaemia cannot be assumed to impart a similar benefit on quality of life. The latter concept must therefore be analysed independently.

Activities of Daily Living

Quality of life analysis in patients with lower limb ischaemia: suggestions for European standardisation.

INTRODUCTION AND OBJECTIVES: In this era of evidence-based medicine and limited resources we seem obliged, on clinical and economic grounds, to demonstrate that we improve not only patient survival but also the quality of patients' lives. This study aims to determine the impact of increasing lower limb ischaemia on quality of life (QOL) and which of three commonly used generic QOL instruments is the most valid, reliable, and responsive to change in patients with lower limb ischaemia. PATIENTS AND METHODS: Two hundred and thirty-five patients, 144 men and 91 women, median age 68 years (range 41-87 years) were graded according to ISCVS suggested reporting standards, i.e. 16 mild, 116 moderate and 25 severe claudicants; 33 patients had rest pain and 45 tissue loss. Patients completed Short Form 36 (SF36), EuroQol (EQ-5D) and Nottingham Health Profile (NHP) questionnaires at interview. Additional copies of questionnaires were posted to 80 patients prior to attendance. Correlation between the two sets of responses reflects test-retest reliability. Correlation between domains measured by the three instruments reflects convergent and divergent validity. Kruskal Wallis ANOVA detected QOL changes across the whole group. Spearman Rank was used to analyse validity and reliability. Responsiveness was analysed using the Mann-Whitney U-test. RESULTS: Increasing lower limb ischaemia confers significant (p < 0.05) deterioration in: SF36 measured: physical functioning, physical role, pain, general health, vitality, social functioning and mental health. EQ-5D measured: mobility, self-care, usual activities, pain and anxiety/depression. NHP measured: energy, pain, emotional reaction, sleep, social isolation and physical mobility. All three instruments are significantly reliable (rs > 0.7). The validity of SF36 and NHP (rs = 0.68-0.78) is superior to EQ-5D (rs = 0.37-0.7). SF36 & NHP are equally responsive to changes in physical activity and pain. SF36 and EQ-5D are most responsive to changes in social activity. SF36 is most responsive to changes in psychological status. CONCLUSIONS: QOL deteriorates markedly with increasing lower limb ischaemia. The SF36 would appear to be the most appropriate generic QOL analysis tool for these patients. We recommend its widespread adoption throughout Europe, thus providing a standardised tool for reporting generic QOL.

Activities of Daily Living

The regulation of neutrophil activation and adhesion during femorodistal bypass surgery.

OBJECTIVE: To determine the effect that revascularising chronic critically ischaemic legs has no neutrophil activation and adhesion. DESIGN: Prospective clinical study. SETTING: University Hospital. MATERIALS: Twenty-five patients, 16 men and nine women undergoing femorodistal surgery. CHIEF OUTCOME MEASURES: Venous blood assays for neutrophils expression of CD11b, neutrophil adhesion, and the plasma concentration of the shed endothelial adhesion receptor, soluble intracellular adhesion molecule 1 (sICAM-1). Urinary microalbuminaemia was measured and expressed as an albumin/creatinine ratio (ACR), as a marker of vascular permeability and plasma neutrophil elastase as evidence of neutrophil activation. Venous blood was taken preoperatively, during surgery and for the first 7 days postoperatively. MAIN RESULTS: Neutrophil CD11b expression fell following reperfusion of the limb (21.4 mcf to 9.7 mcf, p < 0.02 Mann Whitney U-test) as did neutrophil adhesion (preop. 75% adhesion, postop. 28% p < 0.01). However, the plasma elastase levels rose from 95 micrograms/l to 345 micrograms/l at 4 h and the ACR increased from 5.3 mg/ml to 304.2 mg/ml. The concentration of sICAM-1 fell following reperfusion (p < 0.04). CONCLUSION: The change in CD11b, sICAM-1 and adhesion may represent a normal immunological response to ischaemia/reperfusion.

Aged