ASAIO transactions / American Society for Artificial Internal Organs
-
A simple, colorimetric protamine titration method was developed for rapid and precise estimation of the protamine dose required for clinical heparin reversal. The method employs azure A dye as the titration indicator, and has replaced the time consuming clotting assay in the conventional protamine titration method with a rapid colorimetric assay. ⋯ In a similar manner, the colorimetric assay can also be employed with a heparin titration procedure to quickly assess the heparin dose required for protamine reversal. This would allow physicians to exercise a quick and accurate heparin back-titration to patients who are overdosed with protamine.
-
Improvements in percutaneous coronary angioplasty (PTCA) have broadened the scope of this therapy to higher risk patients. The authors used an extracorporeal membrane oxygenator (ECMO) system during seven PTCA procedures to provide rapid, safe, cardiopulmonary support for high-risk patients. Six patients underwent femoral cutdown and placement of arteriovenous cannulae before PTCA; one patient was cannulated percutaneously. ⋯ One patient died of retroperitoneal hemorrhage unrelated to the ECMO cannulation site. Six patients survived. This system can be rapidly deployed while providing satisfactory cardiopulmonary support.
-
Extracorporeal techniques for respiratory support in the newborn are feasible, as the growth of neonatal extracorporeal membrane oxygenation (ECMO) has demonstrated. It has been shown, however, that even in severely damaged lungs, sufficient oxygenation and gas exchange can be maintained only by removing CO2 in an extracorporeal circuit, i.e., extracorporeal CO2 removal (ECCO2R). To demonstrate the effectiveness of CO2 removal in a bicarbonate-free hemodialysis procedure, CO2 removal was measured during routine acetate hemodialysis in 22 patients on renal replacement therapy for end-stage renal disease. ⋯ To use bicarbonate-free hemodialysis for total metabolic CO2 removal, acetate dialysate was modified with lactate, phosphate buffer, and sodium hydroxide to compensate for the bicarbonate loss. In sheep, apneic oxygenation could be achieved with blood flow rates as low as 10-15 ml/kg/min for 4-6 hours. These preliminary data suggest that a hemodialysis procedure for bicarbonate and CO2 elimination (ECBicCO2R) could be an efficient method for CO2 removal requiring much lower blood flow rates than techniques presently in use.