Cho JY et al. (2006) Outcome of donors with a remnant liver volume of less than 35% after right hepatectomy. Liver Transpl 12: 201–206

Chan SC et al. (2006) Long-term biological consequences of donor right hepatectomy including the middle hepatic vein in adult-to-adult live donor liver transplantation. Liver Transpl 12: 259–263

Living donor liver transplantation has increased tremendously in popularity since the technique was introduced in 1996, partly because right-lobe hepatectomy allows large grafts to be obtained—up to two-thirds of the donor's liver volume—that make adult-to-adult transplantation feasible. The benefits of large graft volumes are obvious for the recipient, but the long-term sequelae for the donor are still unknown.

Cho et al. transplanted right-lobe grafts without the middle hepatic vein, and found that over the 12 months after surgery, the outcome of 74 donors whose remnant liver volume was <35% of their original liver volume as assessed by CT was no poorer than that of 72 donors whose remnant liver volume was ≥35%. Adequate safety margins would be provided by a lower limit for remnant liver volume of 30%, they suggest.

Chan et al. transplanted right-lobe grafts including the middle hepatic vein, and found that at long-term follow-up (a median of 47.4 months after surgery) the 29 donors' regenerated livers were measurably (although not statistically significantly) smaller than their preoperative volume, as assessed by CT. Interestingly, there was an inverse relationship with remnant liver volume: donors with the biggest liver remnant after hepatectomy had the greatest regeneration deficit.

Even minor donor morbidities should not be ignored, say Cho et al., because a second insult in the setting of hepatic insufficiency after liver donation could initiate a potentially fatal cycle of complications.