Abstract
Although the routine use of alkali buffer is not recommended in patients with respiratory acidosis, some patients may benefit from its administration. A 42-year-old man was treated with venovenous extracorporeal membrane oxygenation (VV-ECMO) and continuous venovenous hemodiafiltration (CVVHDF) due to necrotizing pneumonia and emphysematous cystitis with Klebsiella pneumoniae. Although the sweep gas flow rate of the VV-ECMO was gradually reduced, he failed to wean off VV-ECMO due to respiratory acidosis, followed by tachycardia and tachypnea on the 63rd day of VV-ECMO. Therefore, we mixed sodium bicarbonate in the replacement fluid of CVVHDF for 5 days to avoid an intolerable decrease in blood pH after discontinuing the VV-ECMO sweep gas. When the serum bicarbonate concentration was >30 mmol/L and pH was maintained at >7.30 with a PCO2 of >60 mmHg, VV-ECMO was finally decannulated. Sodium bicarbonate buffer through the replacement of CVVHDF fluid facilitated VV-ECMO weaning in a patient with hypercapnic respiratory failure.