The impact of endovascular repair of ruptured abdominal aortic aneurysm on the gastrointestinal and renal function.

Introduction. Systemic effects of ruptured abdominal aortic aneurysm (rAAA) may be altered by the mode of surgery. This study aimed to determine systemic effects of endovascular aneurysm repair (EVAR) compared to open repair (OR). Patients and Methods. Consecutive patients with rAAA were repaired by OR or EVAR according to computerised tomographic (CT) findings. Renal function was monitored by estimated glomerular filtration rate (eGFR), serum urea and creatinine, and urinary albumin creatinine ratio (ACR). Hepatic function was assessed postoperatively for 5 days. Intestinal function was determined by the paracetamol absorption test. Intestinal permeability was assessed by urinary lactulose/mannitol ratio. Results. 30 rAAA patients were included. Fourteen had eEVAR and sixteen eOR. Serum urea were higher in eOR, while creatinine was similar between groups. Hepatic function showed no intergroup difference. Paracetamol absorption was increased in eEVAR group at day 3 compared to day 1 (P = 0.03), with no similar result in eOR (P = 0.24). Peak lactulose/mannitol ratio was higher in eOR (P = 0.03), with higher urinary L/M ratio in eOR at day 3 (P = 0.02). Clinical intestinal function returned quicker in eEVAR (P = 0.02). Conclusion. EVAR attenuated the organ dysfunction compared to open repair. However, a larger comparative trial would be required to validate this. The clinical trial is registered with reference number EUDRACT: 2013-003373-12.

The inflammatory response to ruptured abdominal aortic aneurysm is altered by endovascular repair.

Introduction. Ruptured abdominal aortic aneurysm (rAAA) causes a significant inflammatory response. The study aims to investigate this response following endovascular and open repair of ruptured AAA. Patients and Methods. Consecutive rAAA patients had either endovascular aneurysm repair (EVAR) or open repair (OR). Blood samples were taken for cytokines, lipid hydroperoxides (LOOH), antioxidants, and neutrophil elastase/ α 1-anti-trypsin complexes (NE/AAT) before surgery, 6 hours after clamp release and 1, 3, 5 days postoperatively. Results. 30 patients were included in the study, with 14 undergoing eEVAR and 16 eOR, with comparable baseline comorbidities, age, and parameters. IL-6 peaked higher in eOR patients (P = 0.04), while p75TNFr was similar between groups except at day 5 (P = 0.04). The NE/AAT concentrations were higher in eOR patients (P = 0.01), particularly in the first postoperative day, and correlated with blood (r = 0.398, P = 0.029) and platelet (r = 0.424, P = 0.020) volume transfused. C-reactive protein rose and lipid hydroperoxide fell in both groups without significant intergroup difference. Vitamins C and E, lycopene, and ß -carotene levels were similar between groups. Conclusion. EVAR is associated with lower systemic inflammatory response compared to OR. Its increased future use may thereby improve outcomes for patients.

Determinants of radiation exposure during EVAR.

OBJECTIVES: Endovascular aneurysm repair (EVAR) is an established method of aortic aneurysm repair, in favourable anatomical configurations. It does however expose patients to radiation. The study aim was to determine if the aneurysm neck morphology influenced radiation exposure. PATIENTS AND METHODS: All elective and emergency EVAR patients were identified. Elective patients had a bifurcated stent-graft deployed, while emergency patients were repaired with an aorto-uni-iliac stent-graft and fem-fem crossover bypass. Proximal and distal aortic neck diameters, neck length, neck angles and sac diameter were recorded, with the radiation dose, screening time and contrast volume. The two subgroups of elective and emergency patients were compared and correlation between anatomical and radiological parameters calculated by using Pearson's correlation coefficient. RESULTS: 320 (270 male) elective patients and 64 (55 male) emergency patients from October 1998 to October 2008 underwent EVAR. The mean proximal (p = 0.004) and distal (p = 0.01) neck diameters were smaller and mean sac diameter (p < 0.0001) was greater in emergencies. No difference between groups existed in the neck length (p = 0.36) and suprarenal diameter (p = 0.30), sagittal (p = 0.05) and coronal (p = 0.62) neck angles. The screening time (p = 0.053) and contrast volume (p = 0.04) were lower, with a slightly higher radiation dose (p = 0.12) in emergencies. There was no definite correlation between the seven anatomical and three radiological parameters. CONCLUSION: While radiation exposure is different in emergency patients, this is thought due to surgical technique rather than the aneurysm neck morphology.

The vascular and biochemical effects of cilostazol in diabetic patients with peripheral arterial disease.

OBJECTIVES: Cilostazol improves walking in patients with peripheral arterial disease (PAD). We hypothesized that cilostazol reduces diabetic complications in PAD patients. METHODS: Diabetic PAD patients were prospectively recruited to a randomized double-blinded, placebo-controlled trial, using cilostazol 100mg twice a day. Clinical assessment included ankle-brachial index, arterial compliance, peripheral transcutaneous oxygenation, treadmill walking distance and validated quality of life (QoL) questionnaires. Biochemical analyses included glucose and lipid profiles. All tests were at baseline, 6, and 24 weeks. RESULTS: 26 diabetic PAD patients (20 men) were recruited. Cilostazol improved absolute walking distance at 6 and 24 weeks (86.4% vs. 14.1%, P = .049; 143% vs. 23.2%, P = .086). Arterial compliance and lipid profiles improved as did some QoL indices for cilostazol at 6 and 24 weeks. Blood indices were similar at baseline and at follow-up points for both treatment groups. CONCLUSIONS: Cilostazol is a well-tolerated and efficacious treatment, which improves claudication distances in diabetic PAD patients with further benefits in arterial compliance, lipid profiles, and QoL.

Smoking impairs endothelial function in human saphenous vein in an ex vivo model.

The aim of this ex vivo experimental study was to assess the effect of smoking, diabetes mellitus, and hypertension on endothelial function in human saphenous vein, a commonly used conduit for coronary and peripheral arterial bypass surgery. A segment of long saphenous vein harvested during infrainguinal bypass surgery was mounted in an organ bath for isometric tension studies. Vein rings were precontracted to submaximal contraction with phenylephrine, followed by endothelium-dependent relaxation with acetylcholine. Long saphenous vein segments were collected from 26 patients, including five females, with a mean age of 66.4 years (range 48-92). Current smokers had impaired endothelium-dependent relaxation compared to ex- and nonsmokers (10.2%, n=13, vs. 32.9%, n=13; p<0.010). However, ex-smokers and nonsmokers did not have a significant difference in relaxant responses to acetylcholine (29.1%, n=8, vs. 24.6%, n=5; p=nonsignificant [ns]). Similarly, diabetic and nondiabetic patients did not show a significant difference in endothelium-dependent relaxation (23.1%, n=10, vs. 15.6%, n=16; p=ns). The relaxant responses in hypertensive and normotensive patients were not different (20.4%, n=12, vs. 22.5%, n=14; p=ns). Smoking has a deleterious effect on the endothelial function of saphenous vein, and smoking cessation may improve the long-term durability of saphenous vein used as a bypass graft in patients undergoing arterial reconstruction.

The effects of cilostazol on exercise-induced ischaemia-reperfusion injury in patients with peripheral arterial disease.

OBJECTIVES: Cilostazol improves walking distance in peripheral arterial disease (PAD) patients. The study objectives were to assess the effects of cilostazol on walking distance, followed by the additional assessment of cilostazol on exercise-induced ischaemia-reperfusion injury in such patients. METHODS: PAD patients were prospectively recruited to a double-blinded, placebo-controlled trial. Patients were randomised to receive either cilostazol 100mg or placebo twice a day. The primary end-point was an improvement in walking distance. Secondary end-points included the assessment of oxygen-derived free-radical generation, antioxidant consumption and other markers of the inflammatory cascade. Initial and absolute claudication distances (ICDs and ACDs, respectively) were measured on a treadmill. Inflammatory response was assessed before and 30 min post-exercise by measuring lipid hydroperoxide, ascorbate, alpha-tocopherol, beta-carotene, P-selectin, intracellular and vascular cell-adhesion molecules (I-CAM and V-CAM), thromboxane B(2) (TXB(2)), interleukin-6, interleukin-10, high-sensitive C-reactive protein (hsCRP), albumin-creatinine ratio (ACR) and urinary levels of p75TNF receptor. All tests were performed at baseline and 6 and 24 weeks. RESULTS: One hundred and six PAD patients (of whom 73 were males) were recruited and successfully randomised from December 2004 to January 2006. Patients who received cilostazol demonstrated a more significant improvement in the mean percentage change from baseline in ACD (77.2% vs. 26.6% at 6 weeks, p=0.026 and 161.7% vs. 79.0% at 24 weeks, p=0.048) as compared to the placebo. Cilostazol reduced lipid hydroperoxide levels compared to a placebo-related increase before and after exercise (6 weeks: pre-exercise: -11.8% vs. +5.8%, p=0.003 and post-exercise: -12.3% vs. +13.9%, p=0.007 and 24 weeks: pre-exercise -15.5% vs. +12.0%, p=0.025 and post-exercise: -9.2% vs. +1.9%, p=0.028). beta-Carotene levels were significantly increased in the cilostazol group, compared to placebo, before exercise at 6 and 24 weeks (6 weeks: 34.5% vs. -7.4%, p=0.028; 24 weeks: 34.3% vs. 17.7%, p=0.048). Cilostazol also significantly reduced P-selectin, I-CAM and V-CAM levels at 24 weeks as compared to baseline (p<0.05). There was no difference between treatment groups for ascorbate, alpha-tocopherol, interleukin-6 and -10, hsCRP and p75TNF receptor levels. CONCLUSIONS: Cilostazol significantly improves ACD, in addition to attenuating exercise-induced ischaemia-reperfusion injury, in PAD patients.

The Immediate Management of the Patient with Rupture: Open Versus Endovascular repair (IMPROVE) aneurysm trial--ISRCTN 48334791 IMPROVE trialists.

BACKGROUND: Systematic reviews have suggested a survival advantage for patients with ruptured abdominal aortic aneurysm (AAA), who are managed by endovascular repair. These reviews are based on single centre experiences of selected patients. OBJECTIVE: To determine whether a policy of endovascular repair improves the survival of all patients with ruptured AAA. METHODS: A randomized controlled trial, IMPROVE (ISRCTN 48334791) will randomize patients with a clinical diagnosis of rAAA, made in hospital, either to immediate CT scan and endovascular repair whenever anatomically suitable (endovascular first), or to open repair, with CT scan being optional (normal care), The trial is set on a background of guidelines for emergency care, CT scanning and anaesthesia, which incorporate the protocol of permissive hypotension. Recruitment started in October 2009 and 600 patients are required to show a 14% survival benefit at 30 days (primary outcome) for the endovascular first policy. Recruitment will be from the UK and Europe. Secondary outcomes include 24h, in-hospital and 1 year survival, complications, major morbidities, costs and quality of life. DISCUSSION: This is a "real life" trial that will answer the fundamental relevant clinical dilemma, namely, do patients who present with ruptured AAA derive benefit from treatment in a system, which offers a preferential strategy of endovascular repair? The trial addresses whether the anticipated reduced mortality and morbidity associated with endovascular repair is offset by the relatively greater ease of access and speed to conventional surgery. This issue is pivotal to future patient care and provision of services.

Systematic review of utilities in abdominal aortic aneurysm.

INTRODUCTION: Two main treatments exist for the repair of abdominal aortic aneurysm (AAA). Open surgical repair has been the standard treatment, but more recently endovascular aneurysm repair (EVAR) has been introduced as a less invasive technique. To compare the long-term outcomes of these, utility outcomes have been suggested to be relevant. OBJECTIVE: To review studies comparing the utility outcomes of open repair and EVAR treatment for AAA. DESIGN: database search with strict inclusion and exclusion criteria. MATERIALS AND METHODS: The search was performed in PubMed and EMBASE covering terms relating to AAA and utility. Studies were analysed qualitatively. RESULTS: 10 studies of AAA met the review criteria. The comparative utility scores for the different treatments varied considerably between studies. A Canadian cohort study estimated EVAR as more favorable than open repair, while randomised controlled trials reported lower utilities with EVAR, except for one month post-surgery in the EVAR 1 trial. Furthermore, after screening for AAA, patients testing positive gave similar QoL-5D scores, but worse visual analogue scores than those testing negative. CONCLUSION: There were few studies calculating utilities in AAA, with inconsistent findings. The limited reporting of data prevents in-depth analysis to explain the differences.

Role of endovenous laser treatment in the management of chronic venous insufficiency.

Endovenous laser therapy (EVLT) is a recognized option in the treatment of uncomplicated varicose veins. This uncontrolled case series evaluates its effectiveness in the management of chronic venous insufficiency. Patients with a history of active or healed ulcers were selected for EVLT. The procedure was carried out in an outpatient setting over a period of 12 months. Assessment was carried out for evidence of ulcer healing and recurrence, long saphenous vein occlusion, and patient satisfaction at 3, 12, and 22 months. Results are expressed as means with range. EVLT was used to treat 23 limbs in 20 patients with a median age of 59 years (range 32-76) including 12 females and eight males. All patients had evidence of chronic venous insufficiency, graded at C5 or greater on the CEAP classification (C5 16, C6 7). Patients with long saphenous vein insufficiency were included, whereas those with either deep or combined deep and superficial venous incompetence were excluded. The cumulative 3-, 12-, and 22-month healing rates were 87% (20/23), 100% (23/23), and 95% (21/22), respectively. The only patient having a recurrence of ulcers at 22 months' follow-up (CEAP 6) had mid-calf perforator incompetence with recanalized long saphenous vein. Duplex scan demonstrated long saphenous vein occlusion in 100% (23/23), 96% (22/23), and 91% (20/22) at 3, 12, and 22 months, respectively. In all, 84% (16/19) of patients were satisfied with the results of treatment without any major procedure-related complication. These results demonstrate that EVLT, carried out in an outpatient setting, is effective in the treatment and prevention of chronic venous ulcers, with good patient satisfaction and no major complication.

The low prevalence of abdominal aortic aneurysm in relatives in Northern Ireland.

INTRODUCTION: Mortality from ruptured abdominal aortic aneurysm (AAA) remains high and has given impetus to screening. Targeted screening towards high-risk groups would increase efficacy. Relatives of previous AAA patients have been suggested as one such group. The aim of this study was therefore to determine the prevalence of AAA in relatives of previous patients in Northern Ireland. PATIENTS AND METHODS: All living AAA patients, who underwent surgery between August 2001 and December 2005 in our unit, or were attending for follow-up of small aneurysms were contacted and asked for details of siblings and their family history. Screening by ultrasound was offered to the siblings and children over 50 years, with a defining threshold diameter for an aneurysm of 3.0 cm. Overall prevalence of AAA in the relatives was calculated. Separate prevalence rates were calculated according to relationship and gender of the patient and relative. RESULTS: 513 previous patients were contacted. 132 gave details of living relatives, resulting in a total of 405 relatives suitable for screening. 105 declined a scan, leaving 300 in the study. Overall mean age of the group was 63.0+/-8.7 years and 68% were siblings of male patients. Overall ten AAAs were detected by screening, giving a prevalence of 3.3%. No aneurysms were found in the subgroup of children, while the highest prevalence (12.5%) was found in brothers of female patients. 20 additional AAAs were reported in these 132 families, resulting in 14 of the 132 families (10.6%) having two or more members with AAA. CONCLUSION: The prevalence of screening detected AAA in this study is lower than anticipated. The reason is unclear, but demonstrates the multifactorial nature of the aetiology and genetic complexities yet to be unravelled by future research.

Validity of the Hardman index to predict outcome in ruptured abdominal aortic aneurysm.

This study assessed the validity of the Hardman index in predicting outcome following open repair of ruptured abdominal aortic aneurysm and whether this scoring system can be used reliably to select patients for surgical repair. Patients undergoing open repair of ruptured abdominal aortic aneurysm in two university teaching hospitals over a 5-year period were identified from a computerized hospital database. Thirty-day mortality was the main outcome measure. Five Hardman index factors were calculated and related to outcome retrospectively. There were 178 patients with a mean age of 73.9 years (range 51-94) and a male to female ratio of 5.4:1. The overall in-hospital mortality was 57.3% (102/178). Univariate analysis of risk factors showed that age >76 years (P = 0.007, odds ratio [OR] 2.34, 95% confidence interval [CI] 1.26-4.37) and electrocardiograghic evidence of ischemia on admission (P = 0.002, OR 3.75, 95% CI 1.57-8.93) were associated with high mortality. However, loss of consciousness (P = 0.155, OR 1.56, 95% CI 0.85-2.86), hemoglobin <9 g/dL (P = 0.118, OR 1.89, 95% CI 0.85-4.22), and serum creatinine >0.19 mmol/L (P = 0.691, OR 1.25, 95% CI 0.42-3.70) were not significant predictors of mortality. Using a multivariate analysis, age >76 years (P = 0.043, OR 2.29, 95% CI 1.03-5.11) and myocardial ischemia (P = 0.029, OR 2.93, 95% CI 1.12-7.67) were again found to be the significant predictors of mortality. The operative mortality was 44%, 46%, 68%, 79%, and 100% for Hardman scores of 0, 1, 2, 3, and 4, respectively. No patient had a score of 5. The Hardman index is not a reliable predictor of outcome following repair of ruptured abdominal aortic aneurysm. High-risk patients may still survive and should not be denied surgical repair based on the scoring system alone. Further evaluation of the risk factors is required to reliably and justifiably exclude those patients in whom the intervention is inappropriate.

Endovascular repair of abdominal aortic aneurysms in patients with severe angulation of the proximal neck using a flexible stent-graft: European Multicenter Experience.

AIM: The aim of this paper was to report the results of a multicenter study on endovascular repair of abdominal aortic aneurysms (AAA) in patients with important angulation of proximal neck using a flexible stent-graft (Aorfix). METHODS: Endovascular repair of AAA using a flexible stent-graft was performed at 16 centers in 29 patients with angulation of proximal neck greater than 45 degrees. Twenty-three patients (79%) had angulation greater than 60 degrees and were therefore contraindicated for repair with other contemporary devices. RESULTS: Technical success was achieved in all but one case (96%). There was one postoperative death due to multiorgan failure following revision of groin wound for hemorrhage. No patients were converted to open repair. One patient had persisting proximal endoleak despite placement of proximal extension. One patient in whom wireform fractures had been detected died from ruptured aneurysm at nearly 4 year follow-up. CONCLUSION: Endovascular repair using a flexible stent-graft is feasible in patients with highly angulated necks. This stent-graft allows the possibility of a to offer repair for patients un-suitable for the currently available commercial grafts. Mid-term results are acceptable and need to be confirmed by longer follow-up and larger series.

Endovenous laser treatment for long saphenous vein incompetence.

BACKGROUND: Endovenous laser treatment is a percutaneous technique used for the treatment of long saphenous vein (LSV) incompetence. This paper presents the results of an uncontrolled case series undertaken to assess the feasibility, safety and efficacy of this technique. METHODS: Some 145 incompetent LSVs in 136 patients with saphenofemoral reflux were treated with endovenous laser. The data were evaluated prospectively. Assessment was carried out at 1 week, 3 and 12 months for LSV occlusion and symptomatic relief. RESULTS: Primary procedural success was achieved in 124 (85.5 per cent) of 145 LSVs. Reasons for primary failure included failed cannulation, failure to pass the guidewire and patient discomfort. At 3 months' follow-up, 105 (89.7 per cent) of 117 veins were totally and nine (7.7 per cent) were partially occluded. At 12 months, 63 (76 per cent) of 83 veins were totally and 15 (18 per cent) were partially occluded. At this stage 73 (88 per cent) of 83 patients remained satisfied, but 26 (31 per cent) had residual or recurrent varicosities. Of these, only five required further treatment. Complications included saphenous nerve injury in one patient and superficial skin burns in a second. CONCLUSION: Endovenous laser treatment for LSV reflux is safe and can be carried out under local anaesthesia in an outpatient setting with good patient satisfaction and low complication rates.

The effect of pravastatin on intima media thickness of the carotid artery in patients with normal cholesterol.

OBJECTIVE: Carotid intima media thickness (IMT) is a good indicator of the severity of atherosclerotic disease. Statins have been found to reduce carotid IMT in patients with hypercholesterolaemia. The aim of this study was to investigate if pravastatin is effective in reducing IMT in normocholesterolaemic patients with carotid artery disease. METHODS: Patients with carotid artery stenosis and normal cholesterol levels who were not on a statin, were recruited. Patients were randomised to receive pravastatin or placebo daily. Serum concentration of cholesterol and IMT of common carotid arteries were measured before randomisation and at 3 monthly intervals thereafter, for 9 months. IMT was analysed to give the mean of a standardised 2 cm of the common carotid artery (CCA). Results are expressed as median (IQR) and comparison made using the Wilcoxon signed ranks test. RESULTS: Fifty-four patients were examined. Twenty-eight patients were randomised to active treatment. There was no difference in demographic details and co-morbid states between the two groups. A significant reduction in cholesterol concentration was observed from 3 months in patients randomised to the pravastatin group [5.14(4.72-5.88) vs. 4.11(3.44-5.33), p < 0.05], while there was also a significant decrease in combined IMT form 6 months [1.53(1.36-1.87) vs. 1.41 (1.33-1.78), p < 0.05]. CONCLUSIONS: The results demonstrate that pravastatin reduces intima media thickness of the common carotid artery in normocholesterolaemic patients with moderate carotid stenosis.

Endovascular repair of abdominal aortic aneurysm in a patient with renal transplant.

Patients with functioning renal transplant who develop abdominal aortic aneurysm can safely be treated with endovascular repair. Endovascular repair of aneurysm avoids renal ischemia associated with cross-clamping of aorta.

Intra-mucosal acidosis as a predictor of cardiac outcome following abdominal aortic aneurysm surgery.

OBJECTIVE: To assess if sigmoid ischaemia is a prognostic indicator of early and late post-operative cardiac morbidity and mortality. MATERIALS AND METHODS: Patients undergoing elective abdominal aortic aneurysm repair (AAAR) were included in the study. Demographic details and risk factors for heart disease were recorded. Sigmoid pHi was measured at the time of surgery using a silicone tonometer and perioperative morbidity and mortality were recorded in all patients. Seven years following surgery the patients and their general practitioners were contacted to determine the patient's health. RESULTS: Thirty-eight patients were included in the study. Within the follow-up period, 22 (58%) had died. Eight patients died of cardiac failure or myocardial infarction. The pHi in patients with cardiac related deaths [6.99 (6.84-7.10)] was significantly lower than those with non-cardiac related deaths [7.11 (7.04-7.21), p<0.05]. Similarly, patients who suffered acute cardiac events (within 30 days following AAA repair) had lower pHi [7.01 (6.88-7.12)] compared to those who did not [7.09 (6.90-7.19), p<0.05]. CONCLUSION: The results show that sigmoid ischaemia is more frequent amongst patients that develop cardiac events after AAAR and is associated with a worse long term outcome. This suggests that global hypoperfusion as a result of an under performing heart may be partly responsible for the sigmoid ischaemia in patients following AAAR. Therefore, low sigmoid pHi may predict an increased risk of cardiac complications in these patients.

The effect of lower limb ischaemia-reperfusion on intestinal permeability and the systemic inflammatory response.

OBJECTIVES: a relationship has been demonstrated between increased intestinal permeability, endotoxaemia and the development of the systemic inflammatory response syndrome (SIRS) after aortic surgery. The aim of this study was to evaluate whether isolated lower limb ischaemia-reperfusion (I/R) injury affects intestinal mucosal barrier function and cytokine release. PATIENTS AND METHODS: four groups of patients were investigated, group I, patients with critical limb ischaemia (CLI) undergoing infra-inguinal bypass surgery (n=18); group II, patients with intermittent claudication (IC) undergoing infra-inguinal bypass surgery (n=14); group III, patients with CLI unsuitable for arterial reconstruction, undergoing major amputation (n=12); and group IV, patients undergoing carotid endarterectomy for symptomatic carotid stenosis (n=13). Intestinal permeability, endotoxaemia and urinary soluble tumour necrosis factor receptors were assessed (p55TNF-R). RESULTS: an increase in intestinal permeability was observed on the 3rd postoperative day only in CLI group. This was found to correlate with arterial clamp time. Patients who had a femoro-distal bypass had significantly higher intestinal permeability compared to those who had femoro-popliteal bypass. Endotoxaemia was not detected in any of the groups. Postoperative urinary p55TNF-R concentrations were significantly higher in CLI group compared to the other groups. These did not correlate with the increased intestinal permeability. CONCLUSIONS: our results support the hypothesis that revascularisation of critically ischaemia limbs leads to intestinal mucosal barrier dysfunction and cytokine release. They also suggest that the magnitude of the inflammatory response following I/R injury is related to the degree of initial ischaemia.

Accentuated oxidative stress following reperfusion injury in diabetic rats.

BACKGROUND: This study investigates whether diabetes mellitus accentuates hind limb ischemia-reperfusion injury. METHODS: Male Wistar rats rendered diabetic (n=40) following injection of streptozotocin were compared to non-diabetic control rats (n=30). Each group was divided into sham, 4 hrs of hind limb ischemia, 4 hrs of ischemia followed by 10, 30 or 60 min of reperfusion. Plasma concentrations of an end-product of lipid peroxidation [malondialdehyde (MDA)] and antioxidants (vitamins A and E) were measured together with the resting membrane potential (RMP) of the gastrocnemius muscle. RESULTS: Following reperfusion, the diabetic group showed greater and more persistent elevation of MDA and greater reduction of antioxidants. This was associated with reduction in the RMP only in the diabetic group. There was significant correlation between MDA level and the RMP in both groups of animals. CONCLUSIONS: These results indicate that oxidative stress following reperfusion injury is greater in the presence of diabetes mellitus. This may lead to a decrease in the RMP and increase in the vascular permeability, which may be associated with more complications.