Fetal cardiac bypass using an in-line axial flow pump to minimize extracorporeal surface and avoid priming volume

Multiresolution Analysis of Heart Rate Variability as Investigational Tool in Experimental Fetal Cardiac Surgery

“…The drive cable of the Hemopump, brought out from the side of the connector, was inserted into the external drive unit of the axial pump. The aim of the design of this extra-corporeal circuit was to reduce fluid dynamic energy loss, with respect to the Y connector previously used with the Hemopump, 9,21 and to require less volume of blood for the priming. The arteriovenous cannulation was achieved by placing arterial and venous cannulae, both primed by means of retrograde fetal blood filling, into the proximal main pulmonary artery and the right appendix respectively.…”

Cardiopulmonary Bypass in Ewe’s Fetus: Advances and Setbacks in Our Learning Curve

“…11,12 Troublesome issues include intervention at an advanced gestational age when benefit is not optimal, difficult access to the cardiac outflow sites, persistent cardiac hypoplasia despite some favorable short-term results, intrauterine growth retardation, premature delivery, fetal death, and placental hypoperfusion. From a technical standpoint, the major challenges to cardiac surgery, specifically in younger fetuses, relate to the necessity of designing a special bypass setup and the danger of fetoplacental impairment.…”

“…From a technical standpoint, the major challenges to cardiac surgery, specifically in younger fetuses, relate to the necessity of designing a special bypass setup and the danger of fetoplacental impairment. 12 The main objective of this study was to examine the feasibility of surgery with fetal bypass, specifically at an early stage of gestation, using different hemodynamic pumps. Our approach paralleled that being used in the neonatal cardiac surgery unit.…”

Hydraulic properties of the Hemopump HP31: a study of the downstream pressure distribution

“…The pressure field at pump's outlet, for each afterload level and for each speed level, was investigated as a measure of the Hemopump's capability to convert kinetic energy into pressure; we demonstrated that this capability depends on the hydraulic characteristics of the circuit in which the pump is investigated. The data suggest that in vitro behaviours can be used to accurately set the experimental assistance and to correctly evaluate the results as in [9,10]. The results presented in this paper also showed how for high afterload and low speed levels the fluid flow can even become negative, indicating a retrograde flow through the axial pump.…”

“…Fixing the constant head at the inlet of the Hemopump and varying the constant head at its outlet, it was possible to draw the characteristic flow curves versus delivered pressure for all the available pump rotating speed levels, to be used as a control grid in defining experimental procedures (cannulation, circuit length, etc.) such as in [9,10].…”