Pre-operative regional block anesthesia enhances operative strategy for arteriovenous fistula creation.

PURPOSE: We aim to assess the effect of regional block anesthesia on vein diameter, type of AVF placement, and fistula size and flow volume. METHODS: 30 patients presenting for AV access procedures were followed prospectively. Vein diameters via venous ultrasound and planned location for AV access were documented. Supraclavicular brachial plexus block was followed by repeat ultrasound and alterations in operative plan were noted. Patients returned to clinic for duplex ultrasound assessment. RESULTS: Average increase from baseline vein diameter with regional block was most pronounced in the lower cephalic (34%), upper cephalic (24.2%), and basilic veins (31.3%) and less in the brachial vein (8.7%). Type of AVF was modified following regional block in 14%. The rate of native AVF placement improved from 89% to 93% with regional block. Twenty-three AVF patients were available for follow-up (mean 24 weeks). Average fistula size was 7.9 mm (CI 6.9-8.9) and all patent fistulas developed flow volume >600 mL/min. Primary patency was attained in 83%. One thrombosis occurred after a basilic artery was lacerated during dialysis access. The average fistula increased 0.33 cm from post-block diameter (SD 0.22, P<.05). CONCLUSIONS: Vein diameter increases significantly in the basilic and cephalic veins following regional block anesthesia and may improve the rate of native fistula placement. Propensity to dilate after regional block anesthesia does not predict size of the fistula.

Transmetatarsal amputation: predictors of healing.

The objective of this study is to determine the predictors of healing after transmetatarsal amputations (TMA) and factors leading to a higher level of amputation. A total of 33 TMA was performed in 31 patients during the 5 years between January 2000 and Jul 2005. All patients were men between the ages of 44 and 82 years (mean, 68 years). The mean follow-up period was 36 months (range, 1-65 months). Twelve (40%) TMA required a subsequent higher level of amputation. Seventeen (57%) TMA were successful. The average time until further proximal amputation after TMA was 3.5 months. Risk factors for subsequent higher amputation by univariate analysis included infrapopliteal arterial occlusion (P < 0.05), tobacco smoking greater than 20 years (P < 0.05), and further TMA debridement (P < 0.05). Upon multivariate analysis, only patients undergoing further TMA debridement were at risk for TMA failure (P = 0.01). The difference in ankle-to-brachial pressure ratio (ABI) between the higher amputation group (ABI = 0.51) and the successful TMA group (ABI = 0.54) was not significant. There were no perioperative deaths after TMA. Five (18%) deaths occurred at a mean of 8.2 months after the TMA. In patients who are walking preoperatively, aggressive TMA is warranted in an attempt to maintain ambulation, recognizing that requirement for further debridement, smoking history, and infrapopliteal occlusion may be predictors of nonhealing and subsequent higher amputation.

Predictors of mortality and management of patients with traumatic inferior vena cava injuries.

The aim of this study was to determine factors that predict mortality in patients with traumatic inferior vena cava (IVC) injuries and to review the current management of this lethal injury. A 7-year retrospective review of all trauma patients with IVC injuries was performed. Factors associated with mortality were assessed by univariate analysis. Significant variables were included in a multivariate regression analysis model to determine independent predictors of mortality. Statistical significance was determined at P < or = 0.05. A literature review of traumatic IVC injuries was performed and compared with our institutional experience. Thirty-six IVC injuries were identified (mortality, 56%; mechanisms of injury, 28% blunt and 72% penetrating). There was no difference in mortality based on mechanism of injury. Injuries with closer proximity to the heart were associated with increased mortality (P < 0.001). Univariate analysis demonstrated that nonsurvivors had a higher injury severity scale, a lower systolic blood pressure in the emergency department, a lower Glasgow coma score (GCS), and were more likely to have thoracotomies performed in the emergency department or operating room. Multivariate analysis revealed that only GCS (P = 0.03) was an independent predictor of mortality. Typical factors predicting mortality were identified in our cohort of patients, including GCS. The mechanism of injury is not associated with survival outcome, although mortality is higher with injuries more proximal to the heart. The form of management by IVC level is reviewed in our patient population and compared with the literature.

Predictors of troponin elevation after percutaneous coronary intervention.

The predictors of troponin release after percutaneous coronary intervention were prospectively assessed in 405 consecutive patients. Troponin release occurred frequently (27%) and was associated with complications during the procedure, including sapheneous vein graft interventions, multistent use, glycoprotein IIb/IIIa use, and a history of hypercholesterolemia.