SFSS is a catastrophic complication that can lead to graft failure and retransplantation [10]. The classic postoperative course is graft dysfunction within the first 2 post-transplant weeks with two of the following: prolonged functional cholestasis (serum total bilirubin levels > 5.0 mg/dL), intractable ascites (1000 mL/day), and/or coagulopathy (INR > 2) [10,11,12,13]. SFSS should be differentiated from graft dysfunction due to other pathological abnormalities [14]. For instance, technical (e.g., arterial or portal occlusion, venous outflow congestion, bile leak), immunological (e.g., acute rejection after LDLT), and infectious (e.g., cholangitis, sepsis) abnormalities can lead to graft dysfunction and overlapped clinical presentation [11, 12]. Moreover, recent studies have documented that GRWR less than 0.8% or GV/SLV less than 40% do not necessarily lead to SFSS [15,16,17,18,19]. Indeed, multiple variables are attributed including preoperative recipient disease severity, donor age, portal pressure and/or flow, graft type, and graft regeneration [3, 17, 20, 21].
This case presents a patient who underwent ABOi-LDLT using extended left with caudate lobe graft that was relatively insufficient as the GV/SLV 35.7% and at high risk of SFSS after the surgery. Early graft dysfunction was imminent giving progressive hyperbilirubinemia and intractable ascites. Radiological evaluation excluded technical problems that may be the cause of the clinical presentation. Liver transaminases were initially high; however, along the 1st postoperative week, a progressive decline towards near normal levels precludes possible acute rejection. Therefore, along with a high postoperative portal flow, SFSS diagnosis was highly suspected. Coagulopathy, represented by high prothrombin time and INR, may be along the clinical presentation of SFSS [10, 14]. However, in their series, Gruttadauria et al. reported that coagulopathy was not a reliable indicator of SFSS [7]. In the present case, though INR values showed a slight increase before splenic artery embolization SAE, they were kept below 1.5 before as well as after portal flow modulation.
High post-perfusion PVP had been reported to negatively impact graft outcome [22, 23]. In the setting of small-for-size graft after LDLT, persistent elevation of PVP causes direct hepatocyte injury due to sinusoidal shear stress, congestion, hemorrhage, and endothelial activation [24,25,26]. Indeed, secondary ischemic changes occur due to adaptive hepatic artery vasoconstriction [27]. A key management strategy is portal flow modulation with partially diverting portal flow via portosystemic shunt [28] and/or portal decompression by splenectomy [3, 29, 30], splenic artery ligation [29, 31], or splenic artery embolization [7, 32, 33]. Following LDLT, maintaining adequate portal inflow is crucial for boosting graft regeneration [34]. In the setting of portal hypertensive liver cirrhosis, high sinusoidal resistance diverts portal flow, via portosystemic collaterals, which may jeopardize the graft [35]. Portal steal phenomenon can also occur due to hepatofugal diversion of portal flow through major (> 1 cm) portosystemic shunts [36, 37] with subsequent graft ischemic injury and possible post-transplantation PV thrombosis [28, 38, 39].
We [40, 41] previously reported the beneficial effects of simultaneous splenectomy for recipients with PVP more than 15 mmHg following graft reperfusion. In addition, we previously described that en bloc division of large portosystemic shunts along with splenectomy should simplify and normalize portal hemodynamics with the best graft outcome [42, 43]. On the contrary, the Tokyo University group reported that splenectomy was an independent predictor for postoperative hemorrhage and sepsis; hence, they restricted simultaneous splenectomy in strictly indicated recipients [44]. Moon et al. compared simultaneous splenectomy to an innovative technique, splenic devascularization in adult LDLT. A higher incidence of procedural-related complications was observed in the splenectomy group, as pancreatic fistula, abscess, and hemorrhage, though, did not reach statistical significance [45]. In the setting of LDLT, simultaneous splenectomy often leads to higher morbidity. In the present case, extensive peri-splenic adhesions put the patient at high risk for simultaneous splenectomy. Attempts to ligate the main splenic artery also make the patient at high risk for distal pancreatic injury which can lead to post-transplant catastrophic pancreatic complications. Moreover, following PV thrombectomy and reperfusion, as we previously described, PVP was relatively adequate [46]; however, PV flow was 520 mL/s. As we have the postoperative optional procedures that are accessible for portal flow modulation, then additional intraoperative procedures were not performed during LDLT until postoperative assessment of graft function and PV flow. For instance, SAE can be an alternative for portal decompression [7, 32, 33] and BRTO can be used for boosting portal hypoperfusion salvaging against portal steal preventing graft ischemia [47]. Postoperative portal hemodynamics were disturbed as PV inflow kept high along with marked intractable ascites and serum hyperbilirubinemia, then postoperative SFSS ensued. SAE effectively reversed early allograft dysfunction and impending SFSS.
Previous reports have already pointed to SAE for post-transplant portal modulation. For instance, Gruttadauria et al. [7] reported a series of six patients; however, all were right lobe graft with mean GRWR 1.282 ± 0.276%. Although the clinical presentation was nearly similar to this report, they did not refer to portal pressure nor flow in the peritransplant management. In the present case, the graft of extended left with caudate lobe was low as GRWR 0.67%. After graft reperfusion, finally, PVP was relatively high as 20 mmHg, while PV flow was relatively low as 520 mL/min. Therefore, we choose to monitor portal hemodynamics and decide further management giving accessible angiographic options postoperatively.
Reported rates of complications after SAE, as splenic abscesses, splenic infarction, infections, bleeding, pancreatitis, or postembolization syndrome (abdominal pain, fever, and increased levels of pancreatic enzymes), widely vary [48, 49]. In the setting of post-transplant SFSS, SAE is a safe and feasible option. Among 54 patients who underwent post-transplant SAE, Presser et al. [32] reported one case of post-splenectomy syndrome (transient leukocytosis and fever which resolve spontaneously shortly after SAE). The present case did not develop any post SAE complications.
Giving post-transplantation portal modulation dilemma [6, 9, 32, 50], postoperative portal modulation can be an alternative to high-risk intraoperative procedures. As portal hyperperfusion is contributed by splenic flow [7], an angiographic intervention can aid and may be more effective in post-transplant portal inflow modulation when necessary. For instance, the present case emphasizes that in the setting of relatively small-for-size graft, post-transplant portal decompression with splenic artery embolization can safely rescue from impending SFSS in case of increased portal inflow postoperatively.
