The use of vascular homografts in pediatric small bowel transplantation: Single-center experience over a decade

Protective Effects of Different Hypothermal Preservation Solutions on Structure and Function of Isolated Rat Arteries

OBJECTIVE

With the increasing application of vascular reconstruction in surgical procedures, allogeneic vessels are becoming more popular in clinical practice due to their abundant sources, precise diameter matching, improved histocompatibility, and higher long-term patency rate. This study aimed to investigate the protective effect of various preservation solutions on the function and structure of the isolated rat abdominal aorta preserved under hypothermal conditions.

METHODS

The study utilized a total of 150 Sprague-Dawley (SD) rats, with 144 rats allocated to the experimental groups and 6 rats allocated to the control groups. The abdominal aorta of the rats was chosen as the subject of our research. The aorta in the experimental groups were randomly assigned to 4 groups: University of Wisconsin (UW) solution group, histidine-tryptophan-ketoglutarate (HTK) solution group, normal saline (NS) group, and sodium lactate Ringer's solution (RS) group. Samples were subjected to examination after preservation periods of 1 day, 3 days, 5 days, 7 days, 14 days, 30 days, and 90 days. Evaluation of vascular physiological function involved detecting and assessing vasoconstriction ability and measuring cell viability through the MTT test. Evaluation of the vascular wall structure involved tension tolerance tests and pathological staining.

RESULTS

The pathogen-positive rate in the HTK group and NS group at 1 month was 16.7%. Regarding the vascular skeleton structure, both the UW group and HTK group exhibited intact structures after 2 weeks of preservation, with slightly edematous collagen and elastic fibers, which was significantly better than that of the NS group and RS group. In terms of cell activity and contractile function, all preservation groups showed similar effects within 2 weeks. However, after 2 weeks, the UW group showed the most favorable preservation effect (P<0.05). In terms of vascular tension, different groups exhibited similar effects within 1 week. However, after 2 weeks, the UW group showed the best preservation effect (P<0.05).

CONCLUSION

All 4 types of preservation solution had a preservation effect on the structure and function of isolated blood vessels during short-term hypothermal preservation. However, after 2-week preservation, the UW solution was found to be the most suitable solution for the preservation of blood vessels.

Vascular reconstruction of segmental intestinal grafts using autologous internal iliac vessels

Background

The aim of this study was to assess whether the autologous internal iliac artery and vein could be used as an interpositional graft for vascular reconstruction in segmental intestinal allografts and autografts.

Methods

Thirty-four intestinal transplants (19 living-related allografts and 15 autografts) were conducted in our programs between January 2011 and January 2019. Patient characteristics, type of vascular reconstruction, and post-operative complications were reviewed.

Results

There were 20 males and 14 females with a median age of 35 years. Of 34 grafts, 22 (64.7%) (11 allografts and 11 autografts) were revascularized using the autologous internal iliac artery and vein for reconstruction. Vascular reconstruction on the back table took 21 ± 6 min to complete. Both total operative time and cold ischemia time tended to be longer in the vascular-reconstruction group than in the direct-anastomosis group (530 ± 226 vs 440 ± 116 and 159 ± 49 vs 125 ± 66 min, respectively), but these differences were not significant. The incidence of vascular thrombosis tended to be higher in the direct-anastomosis group than in the vascular-reconstruction group (16.7% vs 0%, P = 0.118). At a median follow-up of 36.9 months, no stenosis or pseudoaneurysms developed. In 19 allografts, acute rejection occurred in 4 (21.1%) and chronic rejection occurred in 1 (5.2%).

Conclusions

Our results indicate that the use of an autologous internal iliac interposition graft greatly facilitates intestinal graft implantation and minimizes the risk of vascular complications.

Limb sparing surgery with vascular reconstruction for nonrhabdomyosarcoma soft tissue sarcoma in infants: A novel solution using allogenic vein graft from the parent

Surgery continues to remain an integral component of treatment, especially for nonrhabdomyosarcoma soft tissue sarcoma as compared to rhabdomyosarcoma owing to their general insensitivity to chemotherapy. A key determinant of outcomes, particularly for extremity tumors includes complete tumor resection with negative margins; however, a significant limitation for limb salvage surgery is the adherence of sarcomas to vital vascular structures. Hitherto, vascular involvement constituted an adequate reason for amputation. However, modern reconstructive techniques and availability of prosthetic grafts in addition to autologous venous grafts have rendered limb salvage surgery possible in a substantial majority of patients. Vascular resection and reconstruction for extremity soft tissue sarcoma in children have not been used routinely for reasons like the small-caliber of native vessels, limited options for conduits and rapid somatic growth. The situation is inconceivable in infants owing to the contemporaneous diminutive caliber of the vessels. We report two infants with lower extremity nonrhabdomyosarcoma soft tissue sarcoma who underwent limb salvage surgery with resection of femoral vessels following which vascular reconstruction was successfully performed using the great saphenous vein allograft harvested from the father.

Current outcomes after pediatric and adult intestinal transplantation

PURPOSE OF REVIEW

In this article, we will review the outcomes of patients with intestinal transplant (ITx) with a focus on factors affecting long-term graft and patient survival.

RECENT FINDINGS

The most recent International Intestinal Transplant Registry reports a 1-, 5-, and 10-year graft survival of 71%, 50%, and 41% respectively, for ITx grafts transplanted since 2000. Over the past decades, significant improvements have been achieved in short-term graft and patient outcomes for ITx recipients. The improvement in short-term outcomes may be related to the focused treatment of antihuman leukocyte antigen antibodies, the use of induction immunotherapy protocols, refinements in surgical techniques, establishment of dedicated ITx units, and improved postoperative management.However, long-term graft and patient outcomes for ITx recipients remain stagnant. Issues impairing long-term outcomes of ITx include the challenges in the diagnosis and treatment of chronic rejection and antibody-mediated rejection, progressive decline in renal function, and long-term infectious and malignancy risks especially related to cytomegalovirus, Epstein-Barr virus and posttransplant lymphoproliferative disorder after ITx.

SUMMARY

Addressing and preventing early and late complications is the key to improving short-term and long-term outcomes after ITx.