Surgical complications after pancreas transplantation with portal-enteric drainage

Gray-scale, Doppler and contrast-enhanced ultrasound in pancreatic allograft surveillance: A systematic literature review

BACKGROUND

Gray scale ultrasound (US), Doppler and Contrast Enhanced Ultrasound (CEUS) represent important surveillance tools in the early post-operative period after pancreas transplantation (PTx), when complications are more common. This review summarizes the available evidence on their clinical application in this setting.

METHODS

We searched the Pub-Med database from inception to October 2018 for English literature on the clinical use of US, Doppler and CEUS in the post-PTx surveillance. Article selection was carried out according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses criteria (PRISMA).

RESULTS

Twenty-nine articles concerning the clinical applications of US, Doppler and CEUS were identified, 13 of which, involving 264 patients, were focused on the sonographic findings in immunologic rejection, whereas 11 studies reporting on 887 patients were focused on post-PTx vascular complications. The remaining five articles, involving a total of 196 patients, described US or CEUS applied in the study of pancreatic morphology and texture to diagnose peri-graft fluids collections or to obtain experimental data on allograft endocrine function.

CONCLUSIONS

US, Doppler and CEUS have proven to be valuable assets in post-PTx follow up, thanks to the combination of their non-invasiveness with a high accuracy in the detection of early abnormalities, in particular regarding vascular complications. Preliminary experiences are directing towards functional research; however, future prospective trials are necessary to precisely correlate organ perfusion, early abnormalities and allograft function.

Early reexploration for suspected thrombosis after pancreas transplantation

BACKGROUND

Graft thrombosis is the most common cause of early graft loss after pancreas transplantation. Early reexploration may permit salvage or timely removal of the thrombosed graft.

METHODS

This was a retrospective review of 345 pancreas transplants performed at a single center between January 2003 and December 2009. Early reexploration was defined as within 1 week of pancreas transplantation.

RESULTS

Of the 345 transplants, there were 35 early reexplorations. The graft was compromised in 20 cases (57%): 10 venous thromboses, 3 arterial thromboses, 2 combined arterial and venous thrombosis, 2 thromboses secondary to allograft pancreatitis, and 3 cases of positional ischemia without thrombosis. Of these allografts, three reperfused once repositioned and six were successfully thrombectomized for a graft salvage rate of 45%. One of the thrombectomized grafts remained perfused but never functioned and was removed at retransplantation. The 10 remaining compromised grafts that were deemed unsalvageable and required allograft pancreatectomy. Nine of these recipients were retransplanted (eight within 2 weeks) and one was not a retransplantation candidate.

CONCLUSIONS

Reexploration for suspected graft thrombosis after pancreas transplantation resulted in a negative laparotomy rate of 43%, but permitted graft salvage in 45% of compromised grafts.

Pancreas transplantation: advantages of both enteric and bladder drainage combined in a two-step approach

BACKGROUND

Although there is a tendency to perform enteric drainage of pancreas transplants in simultaneous pancreas-kidney (SPK) transplantation, bladder drainage is still preferable in pancreas transplantation alone (PTA) or after a previous kidney transplantation (PAK). Our hypothesis was that enteric conversion of a bladder drained pancreas is an effective and safe procedure. We studied the complication rate and physiological effects of enteric conversion in patients with primary bladder-drained SPK transplantation.

PATIENTS

We performed 51 enteric conversions in bladder-drained SPK transplant recipients. As we observed a low complication rate, with time enteric conversions were also performed for less strict and severe indications.

RESULTS

The main indications for conversion were urological problems, metabolic complications and reflux-pancreatitis. The median transplantation-conversion interval was 12 months (range 2-40 months). Post-operative complications consisted of seven urinary tract infections, two low-grade superficial wound infections, one minor bleeding, one phlebitis and one paralytic ileus. In two patients, a relaparotomy was necessary. No graft rejection following enteric conversion was found. Long-term renal and pancreatic function were not affected by the enteric conversion. Three-year patient, kidney and pancreas survival rates after enteric conversion were 93, 97 and 93%, respectively (censored data).

CONCLUSION

Enteric conversion after pancreas transplantation is an effective and safe procedure. Therefore, we suggest a policy of a two-step approach of primary bladder drainage followed by an enteric conversion of the pancreas in a selected group of SPK patients.

Analysis of late operations in transplant patients

OBJECTIVE

The charts of 174 consecutive patients were analyzed for incidence, etiology, and outcome of late operations (1 month or more posttransplant) following liver (OLT), kidney (KT), or pancreas-kidney (SPK) transplantation.

MATERIALS AND METHODS

Clinical and demographic data were analyzed by chi-square analysis and Fisher exact tests to compare subpopulations. All P values <.05 were considered statistically significant.

RESULTS

Censured data revealed 155 patients who did not suffer death or organ loss within 30 days of transplant. Late operations were performed on 89 occasions in 57 patients (65% occurred within 1 year posttransplant) with 20 patients having two or more late operations. Of these 89 procedures, 40% were emergent, 37% were related to the transplant operation, 38% were related to the initial disease, and 73% were major interventions. Fifty-six procedures were performed by the transplant surgery team and all occurred in the same facility as the transplant.

CONCLUSIONS

Transplant recipients have a high incidence (36%) of late operations, most within the first year and most related to either the transplant or the original disease. This heavy operative load is important in planning resource allocation. Oversight by and involvement of the transplantation service in these procedures may contribute to the favorable outcome of these operations.

High levels of C-reactive protein after simultaneous pancreas-kidney transplantation predict pancreas graft-related complications and graft survival

BACKGROUND

Although pancreas graft-related complications are frequent after simultaneous pancreas-kidney transplantation (SPK), there are no parameters predicting the risk for these complications.

METHOD

A two-center retrospective study was performed in 97 patients who underwent SPK to investigate the peak serum value of c-reactive protein (CRP) during the first 72 hr after SPK in view of graft-related complications and graft survival.

RESULTS

Mean peak CRP was 115.6 +/- 71.5 mg/L. Mean peak CRP was higher in patients needing relaparotomy (n=31) (136.4 vs. 105.8 mg/L, P=0.048), especially when postoperative bleeding was excluded (P=0.015); in patients with graft pancreatitis (P=0.03); and in patients with graft loss (n=19; P<0.001) compared with patients without these complications. With a cut-off of peak CRP at the level of mean plus 1 SD (187.05 mg/L), there was a significantly higher incidence of relaparotomies (P=0.01; bleedings excluded: P=0.003), graft pancreatitis (P=0.03), and pancreas graft loss (P<0.0001) in patients with high peak CRP compared with patients with low peak CRP. No differences were noticed with regard to rejection rate, mortality, and kidney graft loss.

CONCLUSION

Our findings suggest that peak CRP is a helpful parameter in predicting pancreas graft-related complications and pancreas graft survival after SPK. Our results also stress the importance of early graft damage in pancreas transplantation.

Vascularized islet-cell transplantation in miniature swine. I. Preparation of vascularized islet kidneys

BACKGROUND

Whereas clinical pancreatic transplantation has been highly successful in correcting the hyperglycemia of insulin-dependent diabetes mellitus (type 1), the results of islet transplantation have been disappointing. This discrepancy may be because of, at least in part, nonspecific loss of islets during the time required for revascularization. To test this hypothesis, we have designed composite kidney grafts containing vascularized autologous islets that can be used to compare the engraftment potential of vascularized versus nonvascularized islet tissue.

METHODS

(1) Islet-cell isolation: miniature swine underwent either partial pancreatectomy to isolate autologous islets or total pancreatectomy to isolate minor antigen-mismatched islets. Islets were purified from excised pancreatic tissue by enzymatic digestion and discontinuous density gradient purification. Isolated islets were cultured for 3 days before transplant. (2) Creation of vascularized islet kidneys (IK): autologous islets alone (n=6), minor-mismatched islets alone (n=3), and minor-mismatched islets plus simultaneous autologous thymic tissue (n=3) were transplanted beneath the renal capsule of juvenile miniature swine. Minor antigen-mismatched islets were also transplanted into both the vascularized thymic graft of a thymokidney (to produce a thymo-islet kidney [TIK]) and the contralateral native kidney (n=3) and both the host thymus and beneath the renal capsule (n=2). All recipients receiving minor-mismatched islets were treated with a 12-day intravenous (IV) course of either cyclosporine A (CsA) at 10 mg/kg per day or FK506 at 0.15 mg/kg per day. (3) Assessment of Function: to evaluate the function of the transplanted islets, three animals bearing TIK and IK underwent total pancreatectomy 3 months following islet transplantation.

RESULTS

(1) Islet-cell yields: an average of 254,960+/-51,879 (4,452+/-932 islet equivalents [IEQ]/gram of pancreas) and 374,410+/-9,548 (4,183+/-721 IEQ/gram of pancreas) viable islets were obtained by partial pancreatectomy and complete pancreatectomy, respectively. (2) Creation of IK: autologous islets engrafted indefinitely, whereas recipients of minor-mismatched islets alone rejected the islets within 2 months. However, when minor-mismatched islets were implanted into both the thymokidney and the contralateral kidney of animals bearing a thymokidney, the islets engrafted indefinitely in both sites (>3 months). Simultaneous implantation of islets into the host thymus and under the renal capsule also led to permanent engraftment of minor-mismatched islets. (3) Function of vascularized islets: three animals with both a TIK and an IK in place for 3 months underwent total pancreatectomy. All three animals maintained normoglycemia thereafter. In two of these animals, the IKs were removed 2 months after the pancreatectomy, and in both cases normoglycemia was maintained thereafter by the TIK.

CONCLUSIONS

The implantation of islets beneath the autologous renal capsule permitted the establishment of a vascular supply and thereby supported normal islet-cell growth and function. The presence of thymic tissue beneath the autologous renal capsule facilitated the engraftment of minor-mismatched islets, and such grafts achieved results similar to autologous islet transplants. Therefore, the ability to create vascularized islet grafts may provide a strategy for successful islet transplantation across allogeneic and potentially across xenogeneic barriers.

[Arterial reconstruction with detubulated aortic patch in simultaneous kidney-pancreas transplantation]

Simultaneous pancreas kidney transplantation has become an accepted therapy for the treatment of patients with insulino-dependant diabetes and renal chronic failure. The arterial arrangement of the pancreatic graft is necessary in order to avoid surgical complications of vascular thrombosis. We reported three cases of simultaneous pancreas kidney, a simple procedure using aortic arterial patch preleved with the superior mesenteric artery and detubulated, than the splenic artery is directly anastomosed to the patch.