EXPERIMENTAL AND CLINICAL TRANSPLANTATION

As the scarcity of transplantable organs continues to rise, compounded with an aging donor population, transplant surgeons are increasingly confronted with organ offers from less than ideal donors. The presence of a celiomesenteric aneurysm involving the vascular supply of a donor allograft may predispose to vascular complications in the transplanted liver. We present a 61-year-old brain-dead donor who was discovered to have a celiac artery aneurysm during organ recovery. After gross atherosclerotic or mycotic involvement was ruled out and after careful consideration of the vascular reconstructive options, the donor common hepatic artery was divided distal to the aneurysmal dilatation and anastomosed to the recipient bifurcation of the left and right hepatic artery in an end-to-end beveled anastomosis. The postoperative course was unre-markable, with normal blood flow through the anastomosis and no significant com-plications. The recipient is doing well 6 months after transplant. The presence of a celiomesenteric aneurysm should not discourage the use of an otherwise adequate liver graft. Careful vascular reconstruction is encouraged to increase the rate of marginal graft utilization and minimize vascular complications. Liberal postoperative imaging can enable early detection of vascular com-plication and prompt intervention. Through this case, we demons-trate the remarkable potential of less-than-ideal grafts with acceptable posttransplant outcomes.

Key words : Celiomesenteric aneurysm, Extended criteria donor, Liver transplant

Splanchnic artery aneurysms (SAA) are rare vascular pathologic entities involving the celiac artery, superior mesenteric artery, inferior mesenteric artery, and their branches.^1-4 Splanchnic artery aneurysms have a reported incidence ranging from 0.1% to 2% and were previously only diagnosed following rupture or during autopsies.^1,5 However, with the increased utility of diagnostic and therapeutic abdominal procedures, more vascular anomalies are being incidentally diagnosed, although up to 22% of SAAs still present as clinical emergencies.^4-7 Splanchnic artery aneurysms are more common in men; however, when found in women, they are most likely to involve the splenic artery, which is the most common site (60% to 80%) of SAAs in general.^2,4,8 Hepatic arteries are the second most common site (20%), followed by the celiac artery and superior mesenteric artery, which make up 4% to 6% of SAAs.^1,2,8 Arteriosclerosis is a frequently cited cause of SAAs, especially in older men, although its histopathologic cause has been suggested to be more of a secondary rather than a primary process.^2,3,9 The presence of an aneurysm may complicate the arterial anastomosis of the liver transplant, leading to posttransplant vascular complications like hepatic artery thrombosis and hepatic artery stenosis. Careful arterial reconstruction of this vascular anomaly may reduce this risk of vascular complications and improve utilization of a graft that would have been discarded. Herein, we present a case of celiac artery aneurysm (CAA) incidentally found during brain-dead donor liver recovery; the liver was subsequently successfully transplanted after adequate management of the CAA.

A 61-year-old African American man with medical history significant for hypertension, hypercho-lesterolemia, chronic renal disease, chronic substance abuse since age 21, and smoking 1 pack per day since 17 years old was found unresponsive in a hypertensive crisis with fixed, dilated pupils. A head computed tomography showed an intracranial hemorrhage, cerebral edema, and subfalcine herniation. He was pronounced brain dead 24 hours after admission, and his family decided to pursue organ donation. A noncontrast abdominal computed tomography scan showed a prominent celiac trunk (Figure 1).

During liver recovery, we identified a CAA 18 mm in diameter, with the common hepatic, splenic, and left gastric arteries originating from the aneurysm (Figure 2). There was no gross evidence of athe-rosclerotic or mycotic degeneration, and the liver graft was deemed appropriate for transplant.

The recipient was a 55-year-old man with end-stage liver disease secondary to Laennec cirrhosis. His Modified End-Stage Liver Disease score at the time of transplant was 32 based on a creatinine level of 1.26 mg/dL, a bilirubin level of 17.3 mg/dL, and international normalized ratio of 2.86. The recipient hepatectomy was unremarkable. Venovenous bypass was not used during the hepatectomy. We performed a side-to-side vena caval anastomosis. The liver portal vein was flushed with 750 mL of cold 5% albumin. We performed an end-to-end anastomosis of the portal vein. Once the venous reconstruction was performed, the recipient’s proper hepatic artery was dissected down to the level of the hepatic artery bifurcation to create the anastomosis. The donor’s hepatic artery was divided away from the aneurysmal dilatation to the level of the common hepatic artery. The hepatic artery reconstruction was performed in an end-to-end fashion using a Carrel patch from the recipient’s proper hepatic artery bifurcation to donor’s common hepatic artery.

The recipient had good postoperative recovery. His transplant liver ultrasonography scan showed good flow throughout the liver, and the arterial anastomosis flow was 64 cm/s on postoperative day 1. He was extubated on postoperative day 2. His postoperative course was remarkable for acute blood loss anemia and steroid-induced hyperglycemia, which were adequately managed. The patient was started on oral feeding on postoperative day 3 and began ambulating on the same day. With a pro-gressive improvement in his condition and liver function, he was discharged home on postoperative day 10. Since discharge, the recipient has had 2 episodes of cholestasis-induced pruritus at 7 weeks and 2 months posttransplant, which were managed by endoscopic retrograde cholangiopancreatography with sphincterectomy, dilation, and stent placement. At his last (3 months posttransplant) follow-up visit, his ascites and encephalopathy had completely resolved, and abdominal imaging (Doppler ultraso-nography and computed tomography) showed normal flow through the hepatic artery, hepatic veins, and portal vein. The flow through the arterial anastomosis has demonstrated optimal post-operative flow patterns since transplant.

The demand for donor organs far outnumbers available grafts. In the past 10 years, an annual average of 2700 patients in the United States either died waiting for a donor liver or had to be removed from the transplant wait list because they became too sick to undergo liver transplant, accounting for 20% to 26% of all removals from the wait list.¹⁰ Thus, it is incumbent on the transplant community to utilize every accessible graft as long as recipient outcomes are not compromised. Surgeons are now increasingly presented with organ offers from traditionally deemed high-risk or extended criteria donors; these include grafts from elderly donors, donors with hepatis B virus or hepatitis C virus infection, and donors with high body mass index.^11,12

Despite success shown with liver transplant, vascular complications remain the Achilles heel of the operation. They often occur at the site of anastomosis, with hepatic artery thrombosis (shown in up to 20% of recipients13), hepatic artery stenosis (shown in 11% of recipients¹⁴), and other vascular complications associated with high morbidity and mortality. These complications may lead to endothelial necrosis, biliary tree necrosis, or even graft loss, necessitating retransplant.^14,15 Vascular variations or anomalies that require reconstruction predispose to technical errors and risk for vascular complications.^13,16

The presence of an aneurysm in a donor graft may complicate the vascular reconstruction, distor-ting the arterial supply of the graft. However, a thorough work-up for causes of the aneurysm, with specific attention to infectious sources, should render otherwise discarded grafts adequate for transplant. Our review of literature for CAAs in liver donors yielded only 2 case reports, illustrating the apprehension by transplant surgeons to utilize these grafts, which have the potential to achieve good results.^17,18

Herein, we illustrate that a CAA should not dissuade the use of a liver graft if there is no compromise to the integrity of the vessel or vascular reconstruction. It is critical that abnormalities in vessel wall integrity be evaluated in the operating room and infectious sources excluded. We believe that concerns about the risk of vascular com-plications may be addressed by liberal use of ultrasonographic imaging in the immediate posto-perative period to enable early diagnosis of vascular complications and prompt intervention. Flint and associates had a 92% sensitivity in the use of Doppler studies to diagnose hepatic artery thrombosis,¹⁹ whereas Langnas and associates had positively diagnosed 91% of patients with hepatic artery thrombosis, 100% of patients with portal vein thrombosis, and 100% of patients with combined hepatic artery thrombosis and portal vein thrombosis using Doppler imaging.¹⁵ Thus, our case demons-trates the potential that less-than-ideal liver grafts can possess, which can only be achieved by thorough evaluation of all accessible donor sources.

Volume: 19 Issue: 10 October 2021

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