Hypophosphatemia after live donor right hepatectomy

It is known that hypophosphatemia can frequently develop after hepatectomy and may result from an increased renal phosphate leak. However, its clinical significance has not been well defined in live donor right hepatectomy (LDRH). The purpose of this study was to investigate the correlation between postoperative hypophosphatemia and both donor morbidity and the degree of hepatic resection in LDRH.

In all, 88 live liver donors were enrolled, who had undergone right hemihepatectomy between January 2002 and December 2005. Based on the severity of the postoperative hypophosphatemia, we divided the donors into 3 groups: mild (1.5-2.5 mg/dL, n = 30), moderate (1.0-1.5 mg/dL, n = 41), and severe (<1.0 mg/dL, n = 17), and we compared the incidence of complications among these groups. In addition, we investigated the possible correlation between the nadir phosphorus levels and both remnant liver volume and alkaline phosphate (ALP) levels.

All donors developed hypophosphatemia postoperatively. The mean value of the nadir phosphorus levels was 1.4 +/- 0.04 mg/dL. However, no significant difference was observed in the incidence of postoperative complications among the hypophosphatemia groups. The phosphorus level was positively correlated with the remnant liver volume (r = 0.389, P < 0.001), but it was negatively correlated with a postoperative increase in the ALP (r = -0.276, P = 0.014).

Hypophosphatemia developed very frequently after LDRH. However, transient hypophosphatemia was unlikely to lead to severe complications in healthy donors. Therefore, based on the serum level, oral or intravenous phosphorus replacement treatment might be more appropriate than routine aggressive replacement by TPN. In addition, although the factors responsible for posthepatectomy hypophosphatemia have not been identified, they might be substances that are associated with hepatic regeneration.