The International journal of artificial organs
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Comparative Study
Complete extracorporeal removal of metabolic carbon dioxide by alkali administration and dialysis in apnea.
The high mortality rate of patients afflicted with adult respiratory distress syndrome (ARDS) may be due, in part, to the hemodynamic changes and the barotrauma accompanying mechanical ventilation, especially when high positive pressure and oxygen tension are used. Recent experimental evidence suggests that prognosis may be improved by suspending ventilation: in the apneic condition, oxygenation can be maintained by transalveolar oxygen diffusion, while extracorporeal carbon dioxide removal (ECCO2R), achieved with membrane lungs, assures CO2 homeostasis. This technology, however, requires high blood flow rates, and is available only to very few specially equipped centers. ⋯ Sodium and fluid balance were maintained by ultrafiltration. Observations in five dogs confirm that systemic pCO2, TCO2, and pH can be maintained well within physiologic ranges, and that prolonged apnea followed by full recovery can be achieved with this methodology. Because of the wide availability of dialysis equipment and expertise, and of lower extracorporeal blood flow requirements, ECCO2R by alkali administration and hemodialysis offers a potentially attractive alternative approach to the use of membrane lungs in the apneic therapy of ARDS.