Evaluation of distal anastomotic intimal hyperplasia: an experimental comparison by arteriography, duplex sonography, angioscopy, and intravascular ultrasound.

Routine follow-up investigation methods after peripheral arterial bypass surgery, such as arteriography and colour duplex sonography, do not always allow correct analysis of moderate alterations in the vessel wall, e.g. initial stages of distal anastomotic intimal hyperplasia (DAIH). The aim of this study was to evaluate the efficiency of angioscopy and intravascular ultrasound compared to the named routine methods regarding detection of early DAIH. Eight months after bilateral femoropopliteal bypass surgery with venous grafts in 18 sheep, we investigated the distal anastomotic sites using the named methods. The findings were then correlated to histologic specimens. Intravascular ultrasound presented the highest sensitivity followed by angioscopy, with results markedly different from the findings arrived at by conventional methods.

Recovery of intraoperatively shed blood in aortoiliac surgery: comparison of cell washing with simple filtration.

To regain blood shed intraoperatively, two different systems are clinically established: washing and centrifuging red blood cells to produce autologous erythrocyte concentrates and devices for immediate reinfusion of whole blood after mere filtration. In a prospective-randomised study to compare both methods regarding their efficiency, adverse effects, and economy, 20 patients of our department undergoing elective aortoiliac surgery received intraoperative autotransfusion by means of either cell-washing (CS) or salvage of whole blood (WB). Patients were preoperatively randomized into one of the two groups and were evaluated with respect to standard metabolic and haematological laboratory parameters preoperatively, during surgery, after transfer into the recovery room, 24 h after surgery, after transfer into the recovery room, 24 h after surgery, and at discharge. Both patient groups were well comparable in demographics, preoperative laboratory data, and indication for operation. Handling was easier, the set-up time was shorter with the whole blood filtration device (10.2 +/- 2.3 versus 21 +/- 1.9 min, p = 0.0023), and no additional personnel was needed to run the system. The whole blood device also allowed a greater percentage of aspirated blood to be returned intraoperatively compared to cell washing (73.5% +/- 7.2 versus 51.1% +/- 6.5, p = 0.03). Thrombocytopenia occurred in 7 (CS) and 3 (WB) patients intraoperatively with a significant difference in platelet count between the two groups (118 +/- 17 [CS] versus 170 +/- 12 [WB]*10(9)/L, p = 0.025). Expected changes in the perioperative course of the clotting parameters such as highly increased PTT levels and moderately prolonged prothrombin times occurred in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)