Effects of Injection Site on the Accuracy of Thermal Washout: Discussion (7)
We did not have any data as to how this respiratory pattern would affect RVEF during the patients’ respiratory cycles; however, we injected the cold water irrespective of respiratory cycle. It is unlikely that the cold water was always injected at any one point of a respiratory cycle and our data could be evaluated as representing the mean at various points through a respiratory cycle. Thermal washout method is based on the theory that successive stroke volumes are relatively constant, and thereby, it is inappropriate to investigate fluctuations in RVEF beat by beat. Further investigation with the aid of other than thermal washout methods is needed. buy ventolin inhalers
What Was Clarified by Comparison of Clinical and Model Experiments?
We did not intend to construct an analogue close to an actual heart, but a sufficient model for investigating what factors affect the thermal washout curve under the condition of complete mixing in a chamber with good heat-insulating properties and known preset EFs and our model was sufficient for these purposes. As clearly shown in Figure 3, EF1 or EF2 obtained from chamber (ventricular) injection was the closest to the actual value, inflow tract (atrial) injection apparently underestimated, and the use of EFmean also resulted in underestimation within the range investigated (EF = 0.4 to 0.62). A possible explanation for this has already been postulated above.