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INTRODUCTION Radiocephalic arteriovenous fistula (RCAVF) creation is the preferred first line hemodialysis access procedure. Analysis of diabetic rat arteriovenous fistula model indicates improved vascular function with HMG-CoA-Reductase Inhibitor (statin) use. We predict similar outcomes in diabetic patients undergoing primary RCAVF placement. METHODS A Veterans Administration Hospital dialysis access database over a fifteen-year period was queried identifying all RCAVF placements in diabetic patients. Patients were stratified into statin medication usage or not at RCAVF creation. Outcomes examined include rate of successful cannulation, functional patency duration, interventions per access, and rates of access thrombosis. Thrombosis-free survival of cannulated RCAVFs were compared using Kaplan-Meier method with log-rank analysis followed by univariate, stepwise logistic regression and ROC curve analysis. RESULTS Total number of 123 RCAVF cases were performed in 122 diabetic male patients. At the time of RCAVF placement, 92 cases were performed on patients that were taking statin medication and 31 cases were performed on patients that were not taking statin medication. There was no difference in terms of rate of successful cannulation, functional patency duration, and number of interventions per access between the statin and non-statin groups. However, rate of RCAVF thrombosis once accessed was significantly lower in the statin group compared to the non-statin group (p=0.0005). Kaplan-Meier survival curve for each group were compared using log-rank test to reveal that diabetic patients who were on statin therapy at the time of operation had significantly higher access survival over time against thrombosis once it was cannulated for dialysis treatment compared to those who were not on statin therapy (p=0.0003). Univariate, stepwise logistic regression model indicated statin use as the only significant factor associated with lack of thrombosis (p=0.05). CONCLUSIONS Statins appear to have protective effects against RCAVF thrombosis as predicted in animal models for diabetic patients undergoing primary RCAVF placements. There were similar functional outcomes in terms of rate of successful cannulation, functional patency duration, and number of interventions per access. These data should encourage further investigation of statins and their role in hemodialysis access.

Background The proximal radial artery fistula (PRA) has been established as an early viable surgical option for arteriovenous fistula creation. The overall assisted primary patency reported in the literature approaches 100% at 1 year. We hypothesize that this excellent patency does not represent a functional result when seen in light of successful cannulation and fistula utilization. Methods We retrospectively queried our Veterans Administration Hospital operative database to identify 284 male patients who had 571 access procedures performed by a senior vascular surgeon attending (R.K.D.) from January 1, 2003, to December 31, 2008. Operative details, patient comorbidities, fistula maturation time (time to first cannulation), functional patency (date of access to abandonment, revision to another fistula type, conversion to a prosthetic graft, thrombosis of the fistula, conversion to peritoneal dialysis, renal transplant, or patient death), and total duration (creation of the fistula to the end of its functional patency) were collected and analyzed. Results A total of 144 PRAs were placed during the study period. In all, 87 patients underwent primary proximal radial artery fistula (P-PRA) placement in a limb without previous access; 57 patients had a secondary proximal radial artery fistula (S-PRA) after a failed previous fistula or graft in the same limb. There were no differences between the 2 groups in terms of age, comorbidities, and operative details. A total of 91 patients (63.2%) were receiving hemodialysis at the time of P-PRA or S-PRA placement. Outcomes of P-PRA and S-PRA populations on hemodialysis were examined. There was increased cannulation success (33% vs. 55%; P = 0.00354, Fisher's exact test), functional patency (755.2 ± 661.2 days vs. 405.4 ± 531.9 days; P = 0.0220, Wilcoxon two-sample test), and total duration (859.5 ± 650.7 days vs. 516.8 ± 547.2 days; P = 0.0361, Wilcoxon two-sample test) of S-PRA over P-PRA. There was no difference in endovascular interventions between the 2 groups (1.6 ± 1.0 interventions per access versus 1.1 ± 0.7 interventions per access; P = 0.2109, Wilcoxon two-sample test). Subgroup analysis (analysis of variance) of the S-PRA group indicated that a patent but failing previous access in the same arm was not superior in terms of successful cannulation, functional patency, or total duration when compared with a thrombosed previous access. Conclusions The PRA remains a viable first access procedure undertaken at our institution. Compared with the reported 12-month assisted primary patency of this fistula type, we found a small percentage of PRAs actually being accessed for successful hemodialysis treatment. The S-PRA appears to have a significantly higher successful cannulation rate, functional patency, and total duration time when compared with the P-PRA in patients receiving hemodialysis treatments. The mechanism of these improved outcomes is not known; considering patency or thrombosis of a previous access in the S-PRA group did not predict future access success in the same extremity.

Purpose: The purpose of this study was to evaluate the results of infrainguinal reconstructions with arm vein, lesser saphenous vein, and remnants of greater saphenous vein (ectopic vein grafts). Methods: The records of 222 patients who underwent 257 bypasses were retrospectively reviewed. Most of the grafts were placed for rest pain or tissue loss (88%) and were secondary reconstructions (70%) to the infrapopliteal level (90%). Single-length vein grafts were constructed in 66% of cases, whereas 34% were composite vein grafts. Results: Secondary graft patency was 70%, 52%, and 43% at 1, 3, and 5 years. Single-length grafts had significantly better patency rates at all intervals: 78% versus 56% at 1 year ( p = 0.001), 60% versus 39% at 3 years ( p = 0.004), and 52% versus 29% at 5 years ( p = 0.002). The limb salvage rate was 69% at 5 years. Conclusions: Ectopic vein grafts with primarily arm vein are an acceptable alternative for infrainguinal reconstruction in the absence of suitable ipsilateral greater saphenous vein. (J VASC SURG 1994;20:451-7.)

BACKGROUND The objective of the current metaanalysis was to evaluate the expression patterns of matrix metalloproteinases (MMPs) in patients with head and neck squamous cell carcinoma (HNSCC), to evaluate reported series, and to determine whether there is an expressed value to quantitate the risk of metastasis. METHODS A review of the published literature was conducted according to defined selection criteria. Fixed and random effects models were applied for estimation of the summarized odds ratio and 95% confidence intervals, including a test for homogeneity of the odds ratios of the studies. Finally, forest plots were created to allow for visual comparison of the results and an estimation of heterogeneity. RESULTS The heterogeneity of data collection and statistical methods did not allow final judgments on the significance of immunohistochemical MMP expression analysis in patients with HNSCC or the impact of MMPs in predicting metastatic behavior. Fourteen studies with 710 patients for 5 different MMPs (MMP-1, MMP-2, MMP-3, MMP-9, and MMP-14) were included in the current metaanalysis. The results indicated that MMP-2, MMP-3, MMP-14 possibly played a role in the metastatic behavior of HNSCC tumors. CONCLUSIONS The authors recommended the standardization of staining procedures and evaluation protocols as a necessary step to allow for valid comparisons of the multitude of results published by different study groups. Cancer 2005. © 2005 American Cancer Society.

We examined pulmonary gas exchange in 19 anesthetized dogs during the induction of acute pulmonary edema by intravenous infusion of dextran in saline. We monitored pulmonary capillary pressure by a left atrial catheter, and arterial blood Po2 by an indwelling electrode. PaOO2 remained near normal until just before pulmonary edema was grossly apparent, when it fell precipitously; left atrial pressure mounted to a peak and then declined. The apparent “steady-state” DlCO was reduced as much as 61%, but the dominant cause of hypoxemia was an increased venous admixture (shunt flow) on O2 breathing. Since the shunt was reversible by forcible inflation of the lungs, induced pulmonary edema was probably associated with closure of alveolar units. pulmonary venous admixture (shunt flow) and diffusing capacity; alveolar closure; arterial blood oxygen; tension in vivo; hypoxemia Submitted on August 14, 1963

Metastatic breast carcinoma surrounding the esophagus is rare. Forty-six cases have been reported. Dysphagia is the major symptom. The typical x-ray appearance is extrinsic obstruction of a short segment of esophagus. A patient is presented with total esophageal obstruction which extended from the thoracic outlet to the inferior pulmonary ligament. Problems were encountered in diagnosis and management. Radiation appears to be the treatment of choice for metastatic breast carcinoma which obstructs the esophagus.