Delayed kidney transplantation in combined liver-kidney transplantation, compared with the simultaneous approach, had better survival rates and overall outcomes, especially among cases with a lower kidney donor profile index, researchers reported in a recently published study.
“It is well known that peri-operative kidney dysfunction is a well-established risk factor for recipient mortality in patients undergoing [liver transplantation],” Burcin Ekser, MD, PhD, from the Indiana University School of Medicine, and colleagues wrote. “With this in mind, we introduced a novel approach of delaying the [kidney transplantation] until the recipient of LT have an opportunity to resolve coagulopathy, reduce or stop pressor support, decompress varices, and to clear post liver reperfusion debris that could compromise kidney function.”
To assess the effect of kidney quality — based on kidney donor profile index (KDPI) — and delayed kidney transplantation on patient survival, the researchers retrospectively reviewed the medical records of 130 patients who underwent combined liver-kidney transplantation.
Sixty-nine patients underwent simultaneous transplantation and 61 underwent kidney transplantation that was delayed up to 81 hours.
Additionally, the researchers categorized donors into three KDPI percentiles (1-33%, 34-66% and 67-99%). While donor and recipient demographics were comparable in both groups, donors in the higher KDPI percentiles in both groups had higher MELD scores, were older, more often died of stroke, and were more likely an extended criteria donor than donation after circulatory death (P < .001)
Patients who underwent delayed kidney transplantation received more extended criteria donor kidneys (15% vs. 6%; P < .01) and had longer kidney cold ischemia time (50.2 vs. 9.9 hours; P < .001) than those who underwent simultaneous transplantation. Simultaneous transplantation recipients received significantly more donation after circulatory death kidneys than delayed transplantation patients (11% vs. 1%; P < .01).
Among simultaneous transplantation recipients, kidney loss and death rates within 90 days and within 1 year posttransplant were higher in the higher KDPI groups. According to the researchers, this was strongly attributed to delayed graft function. Kidney loss among the delayed transplantation recipients, however, was most frequently due to patient death related to cardiogenic or other reasons.
“The impact of KDPI was obvious on patient survival regardless of whether [combined liver-kidney transplantation] was performed simultaneously in the first era, or with the delayed approach in the second era,” the researchers wrote.
Patients in the lowest KDPI percentile who received simultaneous transplantation had a 3-year posttransplant survival rate of 90%, whereas those in the mid percentile had a survival rate of 65% and survival decreased to 55% in the highest percentile (P = .0191). Similarly, the 3-year survival rates among delayed transplantation recipients were 100% in the lowest KDPI percentile and decreased as KDPI increased (P = .01), though outcomes were still better compared with simultaneous transplantation.
“With further evidence of the recent and current study and by other high-volume transplant centers, we believe that delayed [kidney transplant] in [combined liver-kidney transplant] should be the preferred approach whenever possible,” the researchers concluded. “The delayed approach to [kidney transplant] certainly facilitates expansion of the donor pool by allowing the use of more [extended criteria donor] and [donation after circulatory death] kidneys with similar or even better outcomes.” – by Talitha Bennett
Disclosure: The researchers report no relevant financial disclosures.