Does acid-base equilibrium correlate with remnant liver volume during stepwise liver resection?

Abstract

Small for size and flow syndrome (SFSF) is one of the most challenging complications following extended hepatectomy (EH). After EH, hepatic artery flow decreases and portal vein flow increases per 100 g of remnant liver volume (RLV). This causes hypoxia followed by metabolic acidosis. A correlation between acidosis and posthepatectomy liver failure has been postulated but not studied systematically in a large animal model or clinical setting. In our study, we performed stepwise liver resections on nine pigs to defined SFSF limits as follows: step 1: segment II/III resection, step 2: segment IV resection, step 3: segment V/VIII resection (RLV: 75, 50, and 25%, respectively). Blood gas values were measured before and after each step using four catheters inserted into the carotid artery, internal jugular vein, hepatic artery, and portal vein. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. EH correlated with reduced BE in the hepatic artery. Pco values increased after 75% resection in the jugular vein. In contrast, arterial Po increased after every resection, whereas the venous Po decreased slightly. There were differences in venous [Formula: see text], BE in the hepatic artery, and Pco in the jugular vein after 75% liver resection. Because 75% resection is the limit for SFSF, these noninvasive blood evaluations may be used to predict SFSF. Further studies with long-term follow-up are required to validate this correlation. This is the first study to evaluate acid-base parameters in major central and hepatic vessels during stepwise liver resection. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. Extended hepatectomy correlated with reduced BE in the hepatic artery. Because 75% resection is the limit for small for size and flow syndrome (SFSF), postresection blood gas evaluations may be used to predict SFSF.

Establishing a Porcine Model of Small for Size Syndrome following Liver Resection

“…Therefore, it is necessary to establish experimental models that are similar to the human condition. The anatomy and physiology of pigs are similar to humans [ 9 , 10 ]; therefore porcine models of EH are well-suited to studying the pathophysiology and prediction of SFSS [ 11 – 16 ]. However, SFSS has not been prospectively evaluated following EH with regard to the clinical, laboratory, and histopathological findings.…”

Establishing a Porcine Model of Small for Size Syndrome following Liver Resection

“…Therefore, it is necessary to establish experimental models that are similar to the human condition. The anatomy and physiology of pigs are similar to humans [9,10]; therefore porcine models of EH are well-suited to studying the pathophysiology and prediction of SFSS [11][12][13][14][15][16]. However, SFSS has not been prospectively evaluated following EH with regard to the clinical, laboratory, and histopathological findings.…”

Response to: Comment on “Establishing a Porcine Model of Small for Size Syndrome following Liver Resection”

“…Resection that causes early death without the possibility for potential compensation (irreversible) is not an optimal SFSF model. To establish and understand a proper animal model, enough experience with the anatomy and physiology of the animal is required, especially in the respective field [18–24]. …”