Effect of Remote Ischemic Preconditioning on the Incidence of Contrast-Induced Nephropathy in Patients Undergoing Endovascular Aneurysm Repair (Remote Ischemic Preconditioning-Endovascular Aneurysm Repair Study).

BACKGROUND: Contrast-induced nephropathy (CIN) is a major inconvenience in the use of iodinated contrast media (ICM) and it is associated with a significant increase in morbidity and mortality and cost of hospitalization. Remote ischemic preconditioning (RIPC) is a noninvasive and cost-effective tissue protection technique that has showed to be beneficial in decreasing renal insult in patients receiving intravascular contrast. AIM: The primary outcome of this study is to evaluate the impact of RIPC on the incidence of CIN in patients undergoing endovascular aneurysm repair. METHODS: Patients suffering from aortic aneurysm were recruited prior to the administration of ICM. Randomization was used to assign patients into the control/RIPC groups. Biochemical parameters determined renal function before and after surgery in immediate (24-72 hr) and at 30 days of follow-up. RESULTS: Of the 120 patients included in the study, 98,3% were male. Mean age was 73 years (range: 56-87 years). Diabetes and chronic renal failure (considering estimated glomerular filtration [eGFR] <60) was present prior to administration of ICM in 29.16% and 38.33%, respectively. RIPC was applied in 50% (n = 60) of the patients. A total of 24.17% developed CIN regardless of fluidotherapy, RIPC, and other protective strategies. RIPC did not influence outcomes in terms of incidence on CIN, serum creatinine, urea, eGFR, or microalbuminuria in immediate postoperative period. However, the group of RIPC patients showed a statistically significant benefit in renal function in terms of serum creatinine (1.46 ± 0.3 vs. 1.03 ± 0.5; P < 0.001), urea (61.06 ± 27.5 mg/dL vs. 43.78 ± 12.9 mg/dL; P = 0.003), and an increase in eGFR (56.37 ± 23.4 mL/min/1.73 m2 vs. 72.85 ± 17.7 mL/min/1.73 m2; P = 0.004) at 30 days of follow-up. CONCLUSIONS: RIPC seems to be a reasonable, effective, and low-cost technique to alleviate effects of ICM on the renal parenchyma in endovascular aneurysm repair procedures during short-term postoperative period.

Beneficial effects of intra-arterial and intravenous prostaglandin E1 in intestinal ischaemia-reperfusion injury.

OBJECTIVES: Ischaemia-reperfusion (I/R) injury is encountered in conditions that diminish intestinal blood flow. There is no clinically feasible technique available for mucosal preservation. METHODS: One hundred Wistar rats were subjected to intestinal ischaemia for 15 and 60 min (I15', I60'), followed by 1 and 7 days of reperfusion (R1d, R7d). Rats were subjected to ischaemia by clamping the superior mesenteric artery. Prostaglandin E1 (PGE1) (2.500 ng/kg intra-arterial bolus or 20 ng/kg intravenous infusion) was administered immediately prior to the commencement of the experimental period. Animals were divided into 20 groups: sham (laparotomy alone), sacrificed at 1 or 7 days; saline administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion; prostaglandin E1 administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion, each one for intra-arterial or intravenous administration. Ileal segments were excised and assessed for histopathological score, polymorphonuclear (PMN) leucocytes encountered and myeloperoxidase (MPO) activity measurement. RESULTS: I/R caused deterioration of histological characteristics. Prophylactic administration of PGE1 resulted in a significant decrease in the histological score compared with the respective saline group (analysis of variance, P < 0.005). In groups treated with PGE1, PMN leucocyte infiltration was lower for the 60 min of ischaemia group (I60'/R1d *P = 0.026; I60'/R7d P = 0.015). I15'/R7d did not lead to a significant reduction in PMN infiltration (P = 0.061). Pretreatment with PGE1 attenuates MPO levels after intestinal I/R injury (P < 0.05). No differences were encountered between types of administration. CONCLUSIONS: Results of this study showed that administration of prostaglandin E1 prevents I/R injury by diminishing histological damage parameters, inhibiting PMN leucocyte infiltration and attenuating MPO activity.

Low-molecular-weight heparin for prevention of venous thromboembolism after varicose vein surgery in moderate-risk patients: a randomized, controlled trial.

BACKGROUND: Deep vein thrombosis (DVT) after varicose vein surgery (VVS) is not well recognized. Observational studies have yielded variable estimates of the risk, but evidence from randomized trials is lacking. Our aim was to compare the use of thromboprophylaxis with and without low-molecular-weight heparin (LMWH). METHODS: We prospectively randomized moderate-risk patients scheduled for VVS in two arms. The first group of patients received bemiparin for 10 days at a prophylactic dose, early ambulation, and compression therapy for 3 months; the second group received early ambulation and compression therapy alone. The primary efficacy outcome was the composite of DVT (symptomatic or asymptomatic detected by mandatory, bilateral duplex scan). Secondary efficacy and primary safety end points were superficial venous thrombosis, postoperative bleeding, and clinical pulmonary embolism (PE). We assessed transient and permanent risk factors for venous thromboembolism. RESULTS: Two-hundred sixty-two patients were eligible for evaluation. There were no cases of DVT. There were also no cases of clinical PE, death, or major bleeding. No significant differences were seen between groups in the rates of bleeding episodes. CONCLUSION: The data show no superiority of a short-term regimen of LMWH and early ambulation and compression therapy, as compared with early ambulation and compression therapy alone, in patients undergoing VVS in a moderate-risk population.