An Improved Model of Isolated Hemoperfused Porcine Livers Using Pneumatically Driven Pulsating Blood Pumps

Abstract

Existing liver perfusion models are largely limited by high degrees of ischemic and reperfusion injury and the lack of standardization. To establish a highly standardized perfusion model and minimize reperfusion injury, a porcine liver perfusion model was developed using an artificial heart pump (Buecherl Artificial Heart). This model is characterized by pneumatically driven and pressure controlled blood pumps with pulsating flow characteristics. The perfusion parameters and the integrity of the perfused organ were assessed using hemodynamic and hepatic function tests. In eight porcine liver perfusion experiments the system allowed maintaining stable and physiologic organ function over 3 hours by bile production (5.5 +/- 3.1 ml/30 minutes, resp. 22.9 +/- 8.4 ml cumulative at 180 minutes), oxygen consumption (2.2 +/- 0.2 ml/min/100 g overall mean) and significantly better liver enzyme levels (AST 19.5 +/- 10.1 U/l/100 g, ALT 2.1 +/- 0.8 U/l/min, LDH 57.8 +/- 24.2 U/l/100 g) compared to previous studies. It was also possible to reduce the circulating blood volume to 1,000 ml and to create a compact perfusion system that is adoptable to other organ systems such as the kidneys. The compact size and the absence of magnetic components also allow a use for advanced imaging techniques. In conclusion this optimized perfusion system provides a sound basis for future studies in the area of hepatotoxicity and pharmacology.

Haemoperfused liver as an ex vivo model for organ invasion of Candida albicans

“…3a). Therefore, our set-up was comparable with previously perfused organs (Butler et al, 2002;Nagel et al, 2005).…”

“…Organ harvesting. All organs were harvested under general anaesthesia as described previously (Nagel et al, 2005). Directly after preparation of the blood vessels and after blood harvesting, the liver was flushed via the aorta with 4 l pre-warmed (37 uC) electrolyte infusion solution 153 (Berlin-Chemie) to wash residual blood from the organ.…”

Perfusion settings and additives in liver normothermic machine perfusion with red blood cells as oxygen carrier. A systematic review of human and porcine perfusion protocols

“…The porcine study by Nagel et al . controlled the perfusion with pressure in HA and PV and reported total liver flow rate of 60 ml/min per 100 g liver wet weight, which is far below than reference. The human study by Liu et al .…”

Methods of training using pelvic trainers

“…Recently, the use of perfused isolated organs in box trainers was introduced. This technology was developed originally to investigate homodynamic, enzymatic, and pharmacologic changes in isolated hearts or livers connected to an artificial pump and oxygenator [29]. Currently, laparoscopic training courses using isolated and perfused segments of bowel, liver, gallbladder, or kidneys are available commercially, allowing the surgeon to practice on a bleeding field and get acquainted with the essentials of hemostasis [30].…”