Desmopressin impairs microcirculation in donor pancreas and early graft function after experimental pancreas transplantation

The Use of Vasopressors During Deceased Donor Pancreas Procurement Decreases the Risk of Pancreas Transplant Graft Failure

OBJECTIVES

The objective of this study was to identify the effect of various vasopressors on pancreas graft failure and patient survival.

METHODS

A retrospective analysis of the United Network for Organ Sharing database was performed between 2000 and 2019. Patient and graft survival rates were analyzed up to 5 years posttransplant.

RESULTS

The data included 17,348 pancreas transplant recipients: 12,857 simultaneous pancreas-kidney, 1440 pancreas transplant alone, and 3051 pancreas-after-kidney transplant recipients. Use of dopamine during deceased donor procurement increased graft failure by 18% (hazard ratio [HR], 1.18; P < 0.001). Absence of vasopressor caused graft failure to rise by 8% (HR, 1.08; P = 0.09). Dopamine increased the mortality rate by 37% (HR, 1.37; P < 0.001) and the absence of vasopressor increased the mortality rate by 14% (HR, 1.14; P = 0.02). Phenylephrine and norepinephrine reduced the mortality rate by 10% (HR, 0.90; P = 0.05) and 11% (HR, 0.89; P = 0.10), respectively.

CONCLUSIONS

The absence of vasopressor use or the use of dopamine is associated with a higher risk of both pancreas transplant graft failure and recipient mortality. The use of phenylephrine and norepinephrine reduces the risk of mortality. This information should guide deceased donor hemodynamic support management in anticipation of pancreas procurement for future transplantation.

Results after 13 years of kidney-pancreas transplantation in type 1 diabetic patients in Comunidad Valenciana

INTRODUCTION

Simultaneous pancreas-kidney (SPK) transplant is a proven option of treatment for patients with type 1 diabetes mellitus and related end-stage renal disease, who are candidates for kidney transplantation. The results from the beginning of SPK transplant program in Comunidad Valenciana are presented.

METHODS

Descriptive, retrospective, and single-center study of the pancreas transplant performed at the Hospital Universitari i Politècnic La Fe, from September 2002 to December 2015. Clinical variables from donors and recipients, peri-operative variables, patient survival, and pancreatic graft survival were collected.

RESULTS

Eighty-one patients with type 1 diabetes mellitus (48 males and 33 females, mean age 37.4 ± 5.7 years, mean BMI 24.1 ± 3.4 kg/m², mean duration of diabetes 25.5 ± 6.5 years) received SPK transplantation. The overall patient survival at one, 3, and 5 years were 91.3%, 91.3% and 89.5%, respectively. However, patient survival in the periods 2002-2008 and 2009-2015 were 88.2% and 93.6% at one year, 88.2% and 93.7% at 3 years, and 85.3% and 93.7% at 5 years, respectively (P = 1). The overall pancreatic graft survival at one, 3, and 5 years were 75.2%, 69.1% and 63.2%, respectively. On the other hand, pancreatic graft survival in the periods 2002-2008 and 2009-2015 were 67.5% and 80.6% at one year, 64.7% and 71.8% at 3 years, and 58.8% and 65.3% at 5 years, respectively (P = .0109). Post-transplant complications were: graft rejection 8.6%, venous graft thrombosis 7.4%, graft pancreatitis 4.9%.

CONCLUSIONS

In 13 years' experience of SPK transplantation, patient and pancreatic graft survival and the rate of complications after pancreas transplantation were similar to those of other larger series. The medical-surgical team experience improves pancreatic graft survival without influencing patient survival.

Results after 13 years of kidney-pancreas transplantation in type 1 diabetic patients in Comunidad Valenciana

INTRODUCTION

Simultaneous pancreas-kidney (SPK) transplant is a proven option of treatment for patients with type 1 diabetes mellitus and related end-stage renal disease, who are candidates for kidney transplantation. The results from the beginning of SPK transplant program in Comunidad Valenciana are presented.

METHODS

Descriptive, retrospective, and single-center study of the pancreas transplant performed at the Hospital Universitari i Politècnic La Fe, from September 2002 to December 2015. Clinical variables from donors and recipients, peri-operative variables, patient survival, and pancreatic graft survival were collected.

RESULTS

Eighty-one patients with type 1 diabetes mellitus (48 males and 33 females, mean age 37.4±5.7 years, mean BMI 24.1±3.4kg/m2, mean duration of diabetes 25.5±6.5 years) received SPK transplantation. The overall patient survival at one, 3, and 5 years were 91,3, 91,3 and 89,5%, respectively. However, patient survival in the periods 2002-2008 and 2009-2015 were 88.2 and 93.6% at one year, 88.2 and 93.7% at 3 years, and 85.3 and 93.7% at 5 years, respectively (P=1). The overall pancreatic graft survival at one, 3, and 5 years were 75.2, 69.1 and 63.2%, respectively. On the other hand, pancreatic graft survival in the periods 2002-2008 and 2009-2015 were 67.5 and 80.6% at one year, 64.7 and 71.8% at 3 years, and 58.8% and 65.3% at 5 years, respectively (P=.0109). Postransplant complications were: graft rejection 8.6%, venous graft thrombosis 7.4%, graft pancreatitis 4.9%.

CONCLUSIONS

In 13-year's experience of SPK transplantation, patient and pancreatic graft survival and the rate of complications after pancreas transplantation were similar to those of other larger series. The medical-surgical team experience improves pancreatic graft survival without influencing patient survival.

Pancreatic Blood Flow with Special Emphasis on Blood Perfusion of the Islets of Langerhans

The pancreatic islets are more richly vascularized than the exocrine pancreas, and possess a 5- to 10-fold higher basal and stimulated blood flow, which is separately regulated. This is reflected in the vascular anatomy of the pancreas where islets have separate arterioles. There is also an insulo-acinar portal system, where numerous venules connect each islet to the acinar capillaries. Both islets and acini possess strong metabolic regulation of their blood perfusion. Of particular importance, especially in the islets, is adenosine and ATP/ADP. Basal and stimulated blood flow is modified by local endothelial mediators, the nervous system as well as gastrointestinal hormones. Normally the responses to the nervous system, especially the parasympathetic and sympathetic nerves, are fairly similar in endocrine and exocrine parts. The islets seem to be more sensitive to the effects of endothelial mediators, especially nitric oxide, which is a permissive factor to maintain the high basal islet blood flow. The gastrointestinal hormones with pancreatic effects mainly influence the exocrine pancreatic blood flow, whereas islets are less affected. A notable exception is incretin hormones and adipokines, which preferentially affect islet vasculature. Islet hormones can influence both exocrine and endocrine blood vessels, and these complex effects are discussed. Secondary changes in pancreatic and islet blood flow occur during several conditions. To what extent changes in blood perfusion may affect the pathogenesis of pancreatic diseases is discussed. Both type 2 diabetes mellitus and acute pancreatitis are conditions where we think there is evidence that blood flow may contribute to disease manifestations. © 2019 American Physiological Society. Compr Physiol 9:799-837, 2019.

Cooperative Study of the Spanish Pancreas Transplant Group (GETP): Surgical Complications

Technical failure in pancreas transplant has been the main cause of the loss of grafts. In the last few years, the number of complications has reduced, and therefore the proportion of this problem.

OBJECTIVES

The Spanish Pancreas Transplant Group wanted to analyze the current situation with regard to surgical complications and their severity.

MATERIAL AND METHODS

A retrospective and multicenter study was performed. 10 centers participated, with a total of 410 pancreas transplant recipients between January and December 2013.

RESULTS

A total of 316 transplants were simultaneous with kidney, 66 after kidney, pancreas-only 10, 7 multivisceral and 11 retrasplants. Surgical complication rates were 39% (n=161). A total of 7% vascular thrombosis, 13% bleeding, 6% the graft pancreatitis, 12% surgical infections and others to a lesser extent. Relaparotomy rate was 25%. The severity of complications were of type IIIb (13%), type II (12%) and type IVa (8.5%). Graft loss was 8%. Early mortality was 0.5%. The percentage of operations for late complications was 17%.

CONCLUSIONS

The number of surgical complications after transplantation is not negligible, affecting one in 3 patients. They are severe in one out of 5 and, in one of every 10 patients graft loss occurs. Therefore, there is still a significant percentage of surgical complications in this type of activity, as shown in our country.

Anti-hemorrhagic agents in oral and dental practice: an update

Many oral surgeons in their daily practice have the problem of controlling postoperative bleeding. In surgical, oral and maxillofacial practice, standard anti-hemorrhagic protocols, especially in high risk patients, are obviously required and need to be continuously updated. The purpose of this review is to give a rational insight into the management of bleeding in oral and dental practice through modern drugs and medical devices such as lysine analogues and serine protease inhibitors, desmopressin, fibrin sealants, cyanoacrylates, gelatins, collagen and foams, protein concentrates, recombinant factors, complementary and alternative medicine and other compounds.

Intercellular adhesion molecule-1 blockade attenuates inflammatory response and improves microvascular perfusion in rat pancreas grafts

OBJECTIVES

After pancreas transplantation (PTx), early capillary malperfusion and leukocyte recruitment indicate the manifestation of severe ischemia/reperfusion injury (IRI). Oscillatory blood-flow redistribution (intermittent capillary perfusion, IP), leading to an overall decrease in erythrocyte flux, precedes complete microvascular perfusion failure with persistent blood flow cessation. We addressed the role of intercellular adhesion molecule-1 (ICAM-1) for leukocyte-endothelial interactions (LEIs) after PTx and evaluated the contribution of IP and malperfusion.

METHODS

Pancreas transplantation was performed in rats after 18-hour preservation, receiving either isotype-matched IgG or monoclonal anti-ICAM-1 antibodies (10 mg/kg intravenously) once before reperfusion. Leukocyte-endothelial interaction, IP, erythrocyte flux, and functional capillary density, respectively, were examined in vivo during 2-hour reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry.

RESULTS

In grafts of IgG-treated animals, IP was encountered already at an early stage after reperfusion and steadily increased over 2 hours, whereas erythrocyte flux declined continuously. In contrast, inhibition of ICAM-1 significantly improved erythrocyte flux and delayed IP appearance by 2 hours. Further, anti-ICAM-1 significantly reduced LEI and leukocyte tissue infiltration when compared to IgG; edema development was less pronounced in response to anti-ICAM-1 monoclonal antibody.

CONCLUSION

Intercellular adhesion molecule-1 blockade significantly attenuates IRI via immediate reduction of LEI and concomitant improvement of capillary perfusion patterns, emphasizing its central role during IRI in PTx.

Impact of intensive care on renal function before graft harvest: results of a monocentric study

Background

The aim of life-support measures in brain-dead donors is to preserve the functional value of their organs. In renal transplantation, serum creatinine level is one of the criteria for graft harvest. The aim of this study was to assess the impact of intensive care on donor renal function through two criteria: preharvesting serum creatinine level above 120 μmol/L and the elevation of serum creatinine level above 20% between intensive care unit (ICU) admission and graft harvest.

Methods

Between 1 January 1999 and 31 December 2005, we performed an observational study on 143 brain-dead donors. ICU chronology, hemodynamic, hematosis, and treatment data were collected for each patient from ICU admission to kidney removal.

Results

Twenty-two percent of the 143 patients had a serum creatinine level above 120 μmol/L before graft harvest. The independent factors revealed by multivariate analysis were the administration of epinephrine (odds ratio [OR]: 4.36, 95% confidence interval [CI]: 1.33 to 14.32; p = 0.015), oliguria (OR: 3.73, 95% CI: 1.22 to 11.36; p = 0.021), acidosis (OR: 3.26, 95% CI: 1.07 to 9.95; p = 0.038), the occurrence of disseminated intravascular coagulation (OR: 3.97, 95% CI: 1.05 to 15.02; p = 0.042), female gender (OR: 0.13, 95% CI: 0.03 to 0.50; p = 0.003), and the administration of desmopressin (OR: 0.12, 95% CI: 0.03 to 0.44; p = 0.002). The incidence of elevated serum creatinine level above 20% between admission and graft harvest was 41%. The independent risk factors were the duration of brain death greater than 24 hours (OR: 2.64, 95% CI: 1.25 to 5.59; p = 0.011) and the volume of mannitol (OR: 2.08, 95% CI: 1.03 to 4.21; p = 0.041).

Conclusion

This study shows that the resuscitation of brain-dead donors impacts on their renal function. The uses of epinephrine and mannitol are associated with impairment of kidney function. It seems that graft harvest should be performed less than 24 hours after brain death diagnosis.

Vasopressin in septic shock: effects on pancreatic, renal, and hepatic blood flow

Introduction

Vasopressin has been shown to increase blood pressure in catecholamine-resistant septic shock. The aim of this study was to measure the effects of low-dose vasopressin on regional (hepato-splanchnic and renal) and microcirculatory (liver, pancreas, and kidney) blood flow in septic shock.

Methods

Thirty-two pigs were anesthetized, mechanically ventilated, and randomly assigned to one of four groups (n = 8 in each). Group S (sepsis) and group SV (sepsis/vasopressin) were exposed to fecal peritonitis. Group C and group V were non-septic controls. After 240 minutes, both septic groups were resuscitated with intravenous fluids. After 300 minutes, groups V and SV received intravenous vasopressin 0.06 IU/kg per hour. Regional blood flow was measured in the hepatic and renal arteries, the portal vein, and the celiac trunk by means of ultrasonic transit time flowmetry. Microcirculatory blood flow was measured in the liver, kidney, and pancreas by means of laser Doppler flowmetry.

Results

In septic shock, vasopressin markedly decreased blood flow in the portal vein, by 58% after 1 hour and by 45% after 3 hours (p < 0.01), whereas flow remained virtually unchanged in the hepatic artery and increased in the celiac trunk. Microcirculatory blood flow decreased in the pancreas by 45% (p < 0.01) and in the kidney by 16% (p < 0.01) but remained unchanged in the liver.

Conclusion

Vasopressin caused marked redistribution of splanchnic regional and microcirculatory blood flow, including a significant decrease in portal, pancreatic, and renal blood flows, whereas hepatic artery flow remained virtually unchanged. This study also showed that increased urine output does not necessarily reflect increased renal blood flow.

Do inherited hypercoagulable states play a role in thrombotic events affecting kidney/pancreas transplant recipients?

BACKGROUND

Pancreas graft thrombosis remains the leading non-immunologic cause of graft loss after pancreas transplantation. We studied the role of hypercoagulable states (HCS) in pancreas graft thrombosis (pthx).

METHODS

Between January 1, 1994, and January 1, 2003, 131 pancreas transplant recipients experienced a pthx (n = 67) or other thrombotic events. Fifty-six recipients consented to have their blood drawn and tested for the HCS. These results were compared with a control group of pancreas transplant recipients who did not experience a thrombotic event. Fisher's exact test was used to compare the groups.

RESULTS

We found 18% of the recipients with pancreas thrombosis to have a HCS. Factor V Leiden (FVL) was found in 15% vs. 4% in the control group (p = ns) vs. 3-5% in the general white population. We found 3% of the pancreas thrombosis patients to have a prothrombin gene mutation (PGM) vs. 0% in the control group (p = ns) vs. 1-2% in the general white population.

CONCLUSIONS

Of pancreas transplant recipients with thrombosis, 18% had one or more of the most common factors associated with a HCS (FVL or PGM). This can be compared with 4% in a control group and 4-7% in the general white population, respectively. Although the differences are not statistically significant due to small numbers, we feel that the findings may be clinically relevant. While this is only a pilot study, it may be reasonable to screen select pancreas transplant candidates for HCS, especially FVL and PGM, until more data become available.

Pancreatico-renal composite transplant: a new technique designed to decrease pancreatic graft thrombosis

Pancreas graft thrombosis continues to be a major cause of graft loss. The removal of the donor spleen is accompanied by a significant reduction in pancreas graft blood flow. It is likely that reduced blood flow contributes to thrombosis in concert with other factors. We present a case of simultaneous pancreas and dual kidney transplantation wherein one donor kidney was anastomosed to the splenic vessels of the pancreas graft. The portal venous drainage of the pancreas graft was into the vena cava and duodenal segment was drained into the recipient's jejunum. Intraoperative blood flow determinations using an ultrasonic flow probe around the graft portal vein showed that the placement of the renal graft in the position of the donor spleen improved flow by approximately one-third (e.g. at 15 min after transplantation, 800 cc/min vs. 550 cc/min with the composite vascular pedicle clamped). The perfusion phase of a radionuclide scan on postoperative day 3 showed both transplanted kidneys had brisk and comparable visualization. The patient had an uneventful recovery and was discharged on the seventh postoperative day with normal blood glucose values and a serum creatinine of 1.2 mg/mL. A pancreatico-renal composite graft may decrease the incidence of thrombosis by improving pancreatic graft blood flow.

University of Wisconsion Solution Versus Celsior Solution in Clinical Pancreas Transplantation

INTRODUCTION

This study compared the safety and efficacy of University of Wisconsin solution (UW) and Celsior solution (C) in pancreas transplantation (PTx).

METHODS

A retrospective review of 154 PTx performed over a 61-month period included 77 grafts preserved with UW and 77 with C. The two groups were comparable for both donor and recipient characteristics.

RESULTS

After a mean cold ischemia time of 624 minutes (range 360 to 945 minutes) for UW versus 672 minutes (range 415 to 1005 minutes) for C (P = NS), no primary endocrine nonfunction occurred. Delayed endocrine function was diagnosed in two grafts in the UW group (2.6%) versus none in the C group (P = NS). After a minimum follow-up of 4 months (mean 26.5 +/- 15.2 months), 22 recipients (UW = 11 vs C = 11; P = NS) required relaparotomy. Overall, 18 pancreata were lost due to either patient death with functioning graft (UW = 4 vs C = 1; P = NS) or graft loss due to other reasons (UW = 8 vs C = 5; P = NS). Actuarial 1- and 5-year patient survival rates were 93.5% and 86.8% for UW compared with 98.7% and 98.7% for C (P = .04). Actuarial graft survival rates at the same times were 88.3% and 75.0% for UW compared with 90.4% and 90.4% for C (P = NS).

CONCLUSIONS

Within the range of cold ischemia times reported in this study, UW and C show similar safety and efficacy profiles for PTx.

Reduction of ischemia/reperfusion injury by antithrombin III after experimental pancreas transplantation

BACKGROUND

Graft pancreatitis is a major complication after pancreas transplantation. Antithrombin III (AT III) is an anticoagulatory and anti-inflammatory substance. The aim of our study was to evaluate a prophylactic application of AT III in experimental pancreas transplantation.

METHODS

Pancreas transplantation was performed in rats. Cold ischemia time (University of Wisconsin solution at 4 degrees C) was 12 hours. After 4 hours of reperfusion, pancreatic enzymes were assessed and the pancreas was evaluated by intravital microscopy and histologic and immunohistochemical examination. Recipients were allocated randomly to 2 groups: 1 control group (n = 6) and 1 group in which recipients received 125 IU AT III/kg 30 minutes before reperfusion (n = 6). Six animals that did not undergo transplantation served as healthy controls.

RESULTS

Enzyme levels showed no differences between the 2 transplantation groups but were significantly (P <.05) higher than in the control group. Histologic damage was significantly less evident in animals that received AT III compared with transplantation animals that did not receive AT III. During intravital microscopy, animals receiving AT III showed significantly higher capillary and venular erythrocyte velocities compared with untreated transplantation animals. The leukocyte-endothelium interaction in postcapillary venules was decreased significantly in animals with AT III treatment.

CONCLUSIONS

AT III pretreatment decreases tissue damage by attenuating microcirculatory disturbances and leukocyte adherence in experimental graft pancreatitis by its anti-inflammatory and anticoagulatory properties.

C1-inhibitor reduces hepatic leukocyte-endothelial interaction and the expression of VCAM-1 in LPS-induced sepsis in the rat

INTRODUCTION

Increased leukocyte-endothelial interaction (LEI) leading to hepatic microperfusion disorders is proposed as major contributor for hepatic failure during sepsis. Recently it has been demonstrated that complement inhibition by C1-inhibitor (C1-INH) is an effective treatment against microcirculatory disturbances in various diseases. The purpose of this study was to investigate the influence of C1-INH on microcirculation and LEI in the liver in a rat model of sepsis.

MATERIALS AND METHODS

Rats received lipopolysaccharides (LPS) from Escherichia coli intravenously. Controls received Ringer solution only. Ninety minutes after LPS infusion some animals were treated with C1-INH intravenously (LPS + C1-INH). Others (LPS + SC) and controls (Ringer + SC) received sodium chloride (SC). Hepatic LEI and mean erythrocyte velocity (MEV) were quantified by intravital microscopy (IVM) 90 min after LPS or Ringer infusion (0) and 30, 60, 90 and 120 min following treatment. VCAM-1 m-RNA in hepatic tissue, C3a, TNF-alpha and hepatic enzyme liberation in blood was analysed.

RESULTS

Leukocyte sticking to the endothelial wall in postsinusoidal venules was significantly reduced in the LPS + C1-INH vs. the LPS + SC group 30, 60, 90 and 120 min after treatment. VCAM-1 m-RNA expression in the hepatic tissue was markedly and C3a levels in plasma were significantly reduced in the LPS + C1-INH vs. the LPS + SC group. No differences in TNF-alpha levels were detected between these two groups. MEV was improved in the LPS + C1-INH vs. the LPS + SC group.

CONCLUSIONS

Our results indicate that even upon delayed treatment hepatic adhesion molecule expression and LEI can be reduced by C1-INH. The multifunctional regulator may reduce hepatic microcirculatory disturbances during sepsis under clinical conditions.

Hypercoagulable state associated with kidney-pancreas transplantation. Thromboelastogram-directed anti-coagulation and implications for future therapy

BACKGROUND

The clinical consequences of type 1 diabetes mellitus (IDDM) include diabetic triopathy: retinopathy, nephropathy, and neuropathy, as well as microangiopathy, accelerated atherosclerotic disease, and hypercoagulability. The etiology of the hypercoagulability is multifactorial, involving various clotting factors or pathways (for example platelets, fibrinogen, individual components of the clotting system and/or fibrinolysis in different studies). The development of end-stage renal disease (ESRD), with the uremia-related platelet effect has the potential to protect from the existing hypercoagulable state. This has important implications for surgery, particularly simultaneous pancreas-kidney (SPK) transplantation, where the pancreas has historically been prone to thrombosis. This has led us to perform intra-operative thromboelastograms (TEG's) to evaluate the patient's current coagulation status.

METHODS

A TEG was performed in 85 SPK recipients along with a control group of 54 non-diabetic kidney transplant (KT) recipients.

RESULTS

For each of the 4 TEG coagulation parameters, the SPK recipients were significantly more hypercoagulable than the non-diabetic KT recipients. The use of intra-operative heparin is based on the degree of hypercoagulability by TEG and degree of operative hemostasis. There has been one PT lost to thrombosis (1%) in the first week following transplantation during this time.

CONCLUSION

The use of TEG is a helpful adjunct to SPK surgery, demonstrating the patient's current coagulation status. Nearly all SPK recipients (type 1 IDDM with ESRD) have been demonstrated to be hypercoagulable. The TEG allows the judicious use of anti-coagulation at the time of surgery, and beyond.

Effects of organ preservation, ischemia time and caspase inhibition on apoptosis and microcirculation in rat pancreas transplantation

This study was undertaken to examine the impact of ischemia-reperfusion (I/R) injury on microcirculation and apoptosis in experimental pancreas transplantation. Pancreatic grafts were subjected to different preservation solutions and cold ischemia times (CITs): University of Wisconsin (UW), 6-h CITs (group U6); UW, 18-h CITs (group U18); normal saline, 6-h CITs (group S6); and normal saline, 6-h CITs with Z-Asp-2,6-dichlorobenzoyloxymethylketone (pan-caspase inhibitor; group S6 & CI). Nontransplanted animals served as controls. At 1- and 2-h reperfusion microcirculation was assessed by means of intravital microscopy. Apoptosis was detected by in situ nick end-labeling method (TUNEL) at 2-h reperfusion. Deterioration of microcirculation was lowest in group U6 and highest in groups S6 and S6 & CI compared with controls. The apoptotic index (cells per high power fields) of groups U6, U18 and S6 correlated well with functional capillary density (r=- 0,70, p < 0.0001) and leucocyte sticking (r= 0,69, p < 0.0001) at 1-h reperfusion. Caspase inhibition had no impact on microcirculation but significantly reduced AI compared with group S6 (p < 0.001). These data suggest that pancreatic I/R injury-induced apoptotic cell death well predicts the extent of [corrected] microcirculatory impairment. Caspase inhibition might be a promising strategy in reducing I/R injury in pancreas transplantation.

Does treatment of cadaveric organ donors with desmopressin increase the likelihood of pancreas graft thrombosis? results of a preliminary study

Desmopressin (DDAVP) is commonly used in cadaveric organ donors to treat diabetes insipidus. The thrombogenic potential of DDAVP is well known. Recent animal data have demonstrated that DDAVP impairs pancreas graft (PG) microcirculation and perfusion. The aim of this study was too evaluate the effect of DDAVP on the incidence of PG thrombosis in clinical pancreas transplantation. A retrospective review of simultaneous kidney-pancreas transplant (SKPT) entered in the Scientific Registry of Transplant Recipients (SRTR) between 10/5/87 and 9/27/02 was performed. Patients were included for analysis if there was definitive documentation as to whether DDAVP was (DDAVP-Y) or was not (DDAVP-N) administered to the donor. Both dose and duration of DDAVP treatment were not recorded by SRTR. A total of 2804 SKPTs were available for analysis. Mean follow-up was 1.75 years (range, 1 month to 8.4 years). A total of 1287 SKPT patients (46%) received a PG from a DDAVP-Y donor. Graft ischemia times, donor and recipient ages, recipient gender distribution, surgical techniques, and immunosuppressive regimens were similar in both groups. The overall incidence of PG thrombosis was 4.3%. The incidence of PG thrombosis in recipients of grafts from DDAVP-Y donors was 5.1% compared to 3.5% in recipients of grafts from DDAVP-N donors (P =.04). Fifty-eight percent of thrombosed PG came from DDAVP-Y donors compared to 42% from DDAVP-N donors (P =.04). We conclude that there appears to be a relationship between donor treatment with DDAVP and PG thrombosis. A prospective study is needed to verify these findings and to determine their clinical significance.

The influence of desmopressin and vasopressors in the donor management on graft function following pancreas transplantation

INTRODUCTION

The use of desmopressin and vasopressors in cadaveric organ donors is considered a risk factor for graft dysfunction following pancreas transplantation by influencing the microcirculation. The aim of this study was to investigate the influence of these substances on early graft function.

PATIENTS AND METHODS

This single-center retrospective trial included 59 patients who underwent simultaneous or solitary pancreas transplantation. The corresponding donor charts were reviewed for the use of vasopressors and desmopressin. Impaired graft function was determined as graft thrombosis or as insulin-dependence for more then 3 days posttransplant. Daily amylase and lipase concentrations from abdominal drains were measured to quantify reperfusion pancreatitis and fistula formation.

RESULTS

Overall, pancreas thrombosis was observed in 4 of 59 (6.8%) recipients. There were no significant differences in thrombosis rate whether the donors received desmopressin (3/38 vs 1/21, P >.1) or the needed vasopressors (3/53 vs 1/9, P >.1). The number of patients who required insulin for more than 3 days posttransplant was comparable whether the donors received desmopressin (9/38 vs 4/21, P >.1), or vasopressors (9/46 vs 3/8, P >.1). At present all recipients with functioning pancreatic grafts (ie, 92.7%) are free of exogenous insulin therapy at 2 to 80 months posttransplant. The amylase/lipase concentrations of peritoneal fluid were independent of the administration of desmopressin or vasopressors in the donors.

CONCLUSION

In this study donor desmopressin and vasopressor administration did not influence graft function after pancreas transplantation.

Brain death impairs pancreatic microcirculation

Brain death (BD) influences the quality of donor grafts in transplantation. To evaluate the impact of BD on pancreas grafts, we investigated the influence of BD on the microcirculation and histology of the pancreas in a rat model of explosive BD. A group of Wistar rats (n=7), rendered brain dead by inflating an intracranially inserted Fogarty catheter was compared with controls (CO) using intravital epifluorescence-microscopy over 4 h after BD induction; functional capillary density (FCD), leukocyte adherence (AL) in post-capillary venules, histology and pancreatic enzymes were investigated. Four hours after BD, FCD decreased (333 +/- 11 vs. baseline 444 cm/cm2 +/- 5 SEM; p<0.01) and showed lower values than CO (388 +/- 9 p<0.01). In BD, AL was increased (628 cells/mm2 +/- 110 SEM vs. baseline 123 +/- 32, and vs. CO 180 +/- 33; p<0.001). BD caused increased histological damage (CO 1.6 score-points +/- 0.7 SD vs. BD 8.3 +/- 7.1; p<0.05). Amylase was higher in BD (p<0.05) but did not reach pathological values. We show for the first time that BD causes relevant changes in pancreatic microcirculation, histology and leukocyte endothelial interaction which might have a serious impact on the function of grafts. New strategies for preventing this damage are therefore highly desirable in order to improve the outcome of pancreas transplantation.

Oxygen radicals promote ICAM-1 expression and microcirculatory disturbances in experimental acute pancreatitis

BACKGROUND/AIMS

The course of pancreatitis is paralleled by a drastic reduction in organ perfusion and increased ICAM-1-mediated leukocyte-endothelial interaction. We aimed to evaluate the effect of oxygen radicals on ICAM-1 expression and the microcirculation in severe acute pancreatitis using the oxygen radical scavenger dimethylsulfoxide (DMSO).

MATERIALS AND METHODS

Severe pancreatitis was induced in rats (n = 32) who were randomly assigned to one of two groups: either 4 ml/kg 50% DMSO/saline (v/v) started 3 h after induction of pancreatitis or 4 ml/kg saline (control). Microcirculation was evaluated by intermittent intravital microscopy. Serum amylase and lipase, histomorphometric changes, immunohistochemistry for ICAM-1 expression and 24-hour survival were investigated.

RESULTS

Leukocyte adherence was significantly reduced (4.4 +/- 0.47 vs. 5.58 +/- 0.69 sticker/100 micro m, p < 0.05), and mean capillary (0.96 +/- 0.06 vs. 0.45 +/- 0.13 mm/s; p < 0.01) and venous erythrocyte velocity (1.16 +/- 0.12 vs. 0.58 +/- 0.16 mm/s, p < 0.01) were significantly increased by DMSO treatment. Microcirculatory disturbances were paralleled by an increase in endothelial ICAM-1 expression, whereas DMSO reduced ICAM-1 expression.

CONCLUSION

DMSO improves pancreatic microcirculation and reduces ICAM-1 expression and subsequent leukocyte adhesion, suggesting an important role of oxygen free radicals in the pathway of endothelial ICAM-1 expression and microcirculatory disturbances in acute pancreatitis.

Characterization of ischemia/reperfusion injury after pancreas transplantation and reduction by application of monoclonal antibodies against ICAM-1 in the rat

BACKGROUND

Reperfusion injury contributes to early organ malfunction after transplantation. The aim of this study was to characterize the ischemia-reperfusion injury after pancreas transplantation and to evaluate the effect of monoclonal antibody therapy against ICAM-1.

METHODS

Twenty-five heterotopic pancreas transplantations were performed in syngenic rats in a no-touch technique. Microcirculation and leukocyte-endothelial interaction in the grafts were evaluated by intravital microscopy at 1 hour (I), 6 hours (II), 12 hours (III), and 24 hours (IV) after reperfusion, and 12 hours after reperfusion (V) in the therapeutic group. In (V) antibodies against ICAM-1 were applied as bolus at reperfusion and continuously for 6 hours. Next to intravital microscopy, histologic scores, myeloperoxidase levels, and ICAM-1 expression were determined.

RESULTS

Microcirculation was significantly reduced in capillaries and postcapillary venules in the time course after reperfusion (capillary: 0.96 +/- 0.08 mm/s [I] to 0.45 +/- 0.07 mm/s [IV] [P <.01]) and was improved significantly by therapy with ICAM-1 antibodies (0.98 +/- 0.06 mm/s, (P <.01). Leukocyte-endothelial interaction significantly increased 6 hours after reperfusion (II) (P <.01). These changes were paralleled by an increased endothelial expression of ICAM-1 in immunohistochemistry. Histologic evaluation showed increased inflammation at 12 hours after reperfusion (P <.01), which could be diminished by the administration of ICAM-1 antibodies (P <.05).

CONCLUSION

Increased endothelial expression of ICAM-1 after pancreas transplantation is positively correlated with microcirculatory impairment. Important steps of pancreatic inflammation take place approximately 6 hours after reperfusion. Prophylactic application of monoclonal antibodies against ICAM-1 reduces reperfusion injury and successfully prevents the occurrence of graft pancreatitis.

Desmopressin inhibits lung and lymph node metastasis in a mouse mammary carcinoma model of surgical manipulation

BACKGROUND AND OBJECTIVES

Desmopressin (DDAVP) is a synthetic derivative of vasopressin with hemostatic and fibrinolytic properties that has been used during surgery in patients with bleeding disorders. Our aim was to investigate the effect of DDAVP on lung and lymph node metastatic cell colonization using a preclinical mouse mammary carcinoma model of subcutaneous tumor manipulation and surgical excision.

METHODS

Female BALB/c mice bearing the highly aggressive F3II mammary carcinoma were subjected to repeated manipulations of primary tumors (0.5 kg/cm(2) during 2 min), followed (or not) by surgical excision. DDAVP was administered intravenously 30 min before and 24 h after each manipulation or surgery, at a dose of 2 microg/kg. At the end of the experiment, mice were sacrificed and necropsied.

RESULTS

Tumor manipulation induced dissemination to the axillary nodes and increased up to 6-fold the number of metastatic lung nodules. Perioperative treatment with DDAVP dramatically reduced regional metastasis. The incidence of lymph node involvement in manipulated animals was 12% with DDAVP and 87% without treatment (P < 0.02). Histopathological analysis of axillary nodes from DDAVP-treated animals showed sinusal histiocytosis and no evidence of cancer cells. Metastatic lung nodules were also reduced about 65% in animals treated with DDAVP (P = 0.026).

CONCLUSIONS

Our results suggest a potential clinical application of DDAVP in the management of breast cancer, as well as other aggressive solid tumors. DDAVP may be useful to reduce the risk of metastatic cell colonization both during and after surgical manipulation.