Aims of the Study: Assessment of the safety and complication rates of different surgical techniques helps to reduce the surgical risks involved in clinical islet allotransplantation. Percutaneous transhepatic (PT) portal vein infusion and mini-laparotomy (MLap) mesenteric vein infusion are two techniques used at our institution during islet transplantation. We reviewed the safety, complications, and technical aspects of the two techniques, with particular attention to the PT technique for tract closure that involves a “sandwich technique” of alternating coils and gelfoam.  
Methods: We performed a retrospective chart review of 49 adult patients who underwent pancreatic islet allotransplantation at our center. We analyzed and compared the demographics, clinical variables, perioperative measures, and serious adverse event (SAE) associated with the PT and MLap groups (Table 1).
Results: A total of 70 islet allotransplants (19 PT and 51 MLap) were performed in 49 recipients (35 female, 14 male). Demographic, clinical, and perioperative variables such as age, BMI, coagulation profiles, LFT’s, RFT’s, ASA scores, and estimated <span>blood loss did not differ between the two groups (all p values>0.1). There were no significant differences between the median durations of anesthesia or surgery for both procedures. The monitored anesthesia care (MAC) to general anesthesia (GA) conversion rates for the PT and MLap groups were 5.6% and 15.2%, respectively. In the PT group, the portal vein was successfully cannulated on the first attempt 78.9% of the time, and required >3 attempts in 10.5%. Three SAE’s occurred in the PT group: one case of symptomatic bleeding and two cases of cholecystitis. One SAE occurred in the MLap group: a non-incarcerated incisional hernia. A partial left portal vein thrombus was noted in the MLap; this was not considered an SAE. All SAE were successfully managed and resolved. The symptomatic bleeding in the PT group resulted from multiple punctures to the liver due to difficulties in tracking the needle tip. No transhepatic tract bleeding occurred in this group.
Conclusion: Both PT and MLap approaches are safe methods for clinical allogeneic islet cell transplantation. Although complications for both procedures were minimal, the MLap group had a significantly lower SAE rate (p=0.02) compared to the PT group at our institution. Though PT is considered less invasive, the MLap technique may reduce injury to the liver and permit direct surgical control of bleeding.