The International journal of artificial organs
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Comparative Study Clinical Trial
Effects of predeposit and intentional perioperative haemodilution on blood saving program in major orthopaedic surgery.
In this study we evaluated the effects of predeposit and intentional perioperative haemodilution on a blood saving program in major orthopaedic surgery. We demonstrated that autologous blood phlebotomy and maintenance of optimal levels of perioperative haemodilution by delaying blood transfusion, even autologous, are efficient techniques in reducing homologous, red blood cell (HRBC) transfusion. ⋯ In conclusion, predeposit and intentional haemodilution obtained by delaying blood transfusions, even autotransfusional, is a correct way of conducting a blood saving program (BSP) in major orthopaedic surgery. These techniques are clinically effective in avoiding or reducing HRBC transfusion.
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Comparative Study
Ozonation of blood during extracorporeal circulation. I. Rationale, methodology and preliminary studies.
We investigated whether exposure of blood ex-vivo to oxygen-ozone (O2-O3) through a gas exchanger is feasible and practical. We first evaluated the classical dialysis-type technique but we soon realized that semipermeable membranes are unsuitable because they are hydrophilic and vulnerable to O3. We therefore adopted a system with hydrophobic O3-resistant hollow fibers enclosed in a polycarbonate housing with a membrane area of about 0.5 m2. ⋯ Finally, we performed several experiments in sheep and defined optimal anticoagulant dose (sodium citrate, ACD), priming solution, volume of blood flow per min, volume and concentration of O2-O3 mixture flowing countercurrent with respect to blood and the time necessary for perfusion in vivo. The biochemical parameters showed that an O3 concentration as low as 10 microg/ml is effective; this means that gas exchange and O3 reactivity are rapid and capable of inducing biological effects. The sheep showed no adverse effects even after 50 min of extracorporeal circulation at higher O3 concentrations (20 to 40 microg/ml) but the exchanger became less effective (low pO2 values) due to progressive clogging with cells.