Improved right heart function with a compliant inflow artificial lung in series with the pulmonary circulation.
BACKGROUND
We previously reported a 50% incidence of immediate right heart failure using a rigidly housed, noncompliant inflow artificial lung in series with the pulmonary circulation in a healthy ovine survival model. Three device modifications resulted: (1) an inflow cannula compliance chamber, (2) an inlet blood flow separator, and (3) modification of the artificial lung outlet geometry, all to reduce resistance and mimic the compliance of the pulmonary vascular bed.


METHODS
In 7 sheep, arterial grafts were anastomosed end-to-side to the proximal and distal main pulmonary artery, with the paracorporeal artificial lung interposed. A pulmonary artery snare between anastomoses diverted full pulmonary blood flow through the artificial lung for up to 72 hours.


RESULTS
Six of 7 sheep exhibited good cardiac function throughout the test period: mean central venous pressure was 6.8 mm Hg (range, 4 to 11 mm Hg), mean cardiac output, 4.17 +/- 0.12 L/min (range, 2.4 to 6.3 L/min); before and after device mean pulmonary arterial pressure, 21.8 and 18.5 mm Hg, and left atrial pressure, 10.8 mm Hg.


CONCLUSIONS
This modified artificial lung prototype with an inflow compliance chamber, blood flow separator, and modified outlet geometry has greatly improved cardiac function and initial survival in our healthy ovine model.
Lick
S D
SD
Department of Surgery, The University of Texas Medical Branch, Galveston, USA. slick@utmb.edu
Zwischenberger
J B
JB
Wang
D
D
Deyo
D J
DJ
Alpard
S K
SK
Chambers
S D
SD
D000714:Anastomosis, Surgical; D000818:Animals; D001187:Artificial Organs; D001794:Blood Pressure; D002302:Cardiac Output; D002496:Central Venous Pressure; D018056:Hemorheology; D020007:Implants, Experimental; D008168:Lung; D008170:Lung Compliance; D011474:Prosthesis Design; D011651:Pulmonary Artery / Q000601:surgery; D011652:Pulmonary Circulation; D011659:Pulmonary Gas Exchange; D012756:Sheep; D016278:Ventricular Function, Right