Unusual Capnography due to Incorrect Assembly of Spring with Absorber Valve into Breathing Circuit - Experience of Normocarbia: A Case Report / 대한구급학회지

ABSTRACT

A focus on patient safety has heightened the awareness of pateint mornitoring. The importantce of clinical application of capnography continues to grow, as reflected by the increasing number of medical societies recommending its use. We recently encountered an abnormal capnography undergoing gastrectomy. It was noted that the waveform was not sustained zero-baseline formation as seen during inspiratory phase, immediately upsloping for expiratory plateau followed by inspiratoy downsloping as like a shape of curare cleft. But PaCO2 was within normal range. We found that the source of the problem was the incorrect (bottom up) assembly of spring with absorber valve into the CUBE, the circle breathing system of Dameca Ventilator. Spring with absorber valve divides CUBE circle into inspiratory and expiratory space. We concluded that the unusual capnography was resulted from the incorrect assembly of it, subsequently mixing of inspiratory and exhaled gases and rebreathing was occurred with the block of a gas flow to CO2 canister. After correcting assembly, the capnography was normalized.