Early predictors of prolonged intensive care utilization following liver transplantation.

INTRODUCTION: Creatinine, bilirubin, and fibrinolysis resistance are associated with multi-organ dysfunction and likely risk factors for prolonged intensive care unit (pICU) stay following liver transplantation (LT). We hypothesize postoperative day-1 (POD-1) labs will predict pICU. METHODS: LT recipients had clinical laboratories and viscoelastic testing with tissue plasminogen activator thrombelastography (tPA TEG) to quantify fibrinolysis resistance (LY30) on POD-1. pICU was defined as one week or longer in the ICU. Logistic regression was used to identify the relationship between POD-1 labs and pICU. RESULTS: Of 304 patients, 50% went to the ICU, with 15% experiencing pICU. Elevated creatinine (OR 6.6, P â€‹< â€‹0.001) and low tPA TEG LY30 (OR 3.7, P â€‹= â€‹0.004) were independent predictors of pICU after controlling for other risk factors. A 9-fold increase in the rate of 90-day graft loss (19% vs 2% p â€‹< â€‹0.001) was observed patients who had these risk factors for pICU. CONCLUSION: Elevated creatine and fibrinolysis resistance are associated with pICU and poor outcomes following LT.

A model for calculating the long-term estimated post-transplant survival of deceased donor liver transplant patients.

BACKGROUND: The estimated long-term survival (EPTS) score is used for kidney allocation. A comparable prognostic tool to accurately quantify EPTS benefit in deceased donor liver transplant (DDLT) candidates is nonexistent. METHODS: Using the Scientific Registry of Transplant Recipients (SRTR) database, we developed, calibrated, and validated a nonlinear regression equation to calculate liver-EPTS (L-EPTS) for 5- and 10-year outcomes in adult DDLT recipients. The population was randomly split (70:30) into two discovery (N = 26,372 and N = 46,329) and validation cohorts (N = 11,288 and N = 19,859) for 5- and 10-year post-transplant outcomes, respectively. Discovery cohorts were used for variable selection, Cox proportional hazard regression modeling, and nonlinear curve fitting. Eight clinical variables were selected to construct the L-EPTS formula, and a five-tiered ranking system was created. FINDINGS: Tier thresholds were defined and the L-EPTS model was calibrated (R2 = 0.96 [5-year] and 0.99 [10-year]). Patients' median survival probabilities in the discovery cohorts for 5- and 10-year outcomes ranged from 27.94% to 89.22% and 16.27% to 87.97%, respectively. The L-EPTS model was validated via calculation of receiver operating characteristic (ROC) curves using validation cohorts. Area under the ROC curve was 82.4% (5-year) and 86.5% (10-year). INTERPRETATION: L-EPTS has high applicability and clinical utility because it uses easily obtained pre-transplant patients characteristics to accurately discriminate between those who are likely to receive a prolonged survival benefit and those who are not. It is important to evaluate medical urgency alongside survival benefit and placement efficiency when considering the allocation of a scarce resource. FUNDING: There are no funding sources related to this project.

Choledochoduodenostomy continues to be a safe alternative for biliary reconstruction in deceased-donor liver transplantation.

Debate continues as to whether choledochoduodenostomy (CDD) can be used instead of Roux-en-Y choledochojejunostomy (CDJ) when duct-to-duct (DTD) is not an option. We hypothesized that CDD and CDJ had similar rates of complications. All deceased-donor liver transplantations from September 2011 to March 2020 were categorized by biliary reconstruction. Primary outcomes were bleeding, bile leak, anastomotic stricture, and cholangitis. Of the 1,086 patients, 812 (74.8%) received a DTD; 225 (20.7%) received a CDD; and 49 (4.5%) received a CDJ. Cholangitis was significantly higher in CDJ compared to DTD and CDD (26.5% vs 6% vs 13.8%, p < 0.0001). When controlling for significant confounders, CDJ had 10.2 higher odds of cholangitis (95% CI 4.4-23.2) compared to DTD, and 3.3 higher odds compared to CDD (95% CI 1.4-7.8). When compared to DTD, CDJ and CDD had significantly lower odds of stricture. CDD continues to be a safe alternative for biliary reconstruction in deceased-donor liver transplantation.

Surgical complications after living and deceased donor liver transplant: The NSQIP transplant experience.

This study used the prospective National Surgical Quality Improvement Program (NSQIP) Transplant pilot database to analyze surgical complications after liver transplantation (LT) in LT recipients from 2017to 2019. The primary outcome was surgical complication requiring intervention (Clavien-Dindo grade II or greater) within 90 days of transplant. Of the 1684 deceased donor and 109 living donor LT cases included from 29 centers, 38% of deceased donor liver recipients and 47% of living donor liver recipients experienced a complication. The most common complications included biliary complications (19% DDLT; 31% LDLT), hemorrhage requiring reoperation (14% DDLT; 9% LDLT), and vascular complications (6% DDLT; 9% LDLT). Management of biliary leaks (35.3% ERCP, 38.0% percutaneous drainage, 26.3% reoperation) and vascular complications (36.2% angioplasty/stenting, 31.2% medication, 29.8% reoperation) was variable. Biliary (aHR 5.14, 95% CI 2.69-9.8, P < .001), hemorrhage (aHR 2.54, 95% CI 1.13-5.7, P = .024) and vascular (aHR 2.88, 95% CI .85-9.7, P = .089) complication status at 30-days post-transplant were associated with lower 1-year patient survival. We conclude that biliary, hemorrhagic and vascular complications continue to be significant sources of morbidity and mortality for LT recipients. Understanding the different risk factors for complications between deceased and living donor liver recipients and standardizing complication management represent avenues for continued improvement.

Challenging the Traditional Paradigm of Supply and Demand in Pediatric Liver Transplantation Through Nondirected Living Donation: A Case Series.

A gap exists between the demand for pediatric liver transplantation and the supply of appropriate size-matched donors. We describe our center's experience with pediatric liver transplantation using anonymous nondirected living liver donors (ND-LLD). First-time pediatric liver transplant candidates listed at our center between January 2012 and June 2020 were retrospectively reviewed and categorized by donor graft type, and recipients of ND-LLD grafts were described. A total of 13 ND-LLD pediatric liver transplantations were performed, including 8 left lateral segments, 4 left lobes, and 1 right lobe. Of the ND-LLD recipients, 5 had no directed living donor evaluated, whereas the remaining 8 (62%) had all potential directed donors ruled out during the evaluation process. Recipient and graft survival were 100% during a median follow-up time of 445 (range, 70-986) days. Of ND-LLDs, 69% were previous living kidney donors, and 1 ND-LLD went on to donate a kidney after liver donation. Of the ND-LLDs, 46% were approved prior to the recipient being listed. Over time, the proportion of living donor transplants performed, specifically from ND-LLDs, increased, and the number of children on the waiting list decreased. The introduction of ND-LLDs to a pediatric liver transplant program can expand the benefit of living donor liver transplantation to children without a suitable directed living donor while achieving excellent outcomes for both the recipients and donors.

Understanding the Impact of Pneumonia and Other Complications in Elderly Liver Transplant Recipients: An Analysis of NSQIP Transplant.

Despite an increasing demand for liver transplantation in older patients, our understanding of posttransplant outcomes in older recipients is limited to basic recipient and graft survival. Using National Surgical Quality Improvement Program Transplant, we tracked early outcomes after liver transplantation for patients >65. METHODS: We conducted a retrospective analysis of patients in National Surgical Quality Improvement Program Transplant between March 1, 2017 and March 31, 2019. Recipients were followed for 1 y after transplant with follow-up at 30, 90, and 365 d. Data were prospectively gathered using standard definitions across all sites. RESULTS: One thousand seven hundred thirty-one adult liver transplants were enrolled; 387 (22.4%) were >65 y old. The majority of older recipients were transplanted for hepatocellular carcinoma. The older cohort had a lower lab Model for End-Stage Liver Disease and was less likely to be hospitalized at time of transplant. Overall, older recipients had higher rates of pneumonia but no difference in intensive care unit length of stay (LOS), total LOS, surgical site infection, or 30-d readmission. Subgroup analysis of patients with poor functional status revealed a significant difference in intensive care unit and total LOS. Pneumonia was even more common in older patients and had a significant impact on overall survival. CONCLUSIONS: By targeting patients with hepatocellular carcinoma and lower Model for End-Stage Liver Diseases, transplant centers can achieve nearly equivalent outcomes in older recipients. However, older recipients with poor functional status require greater resources and are more likely to develop pneumonia. Pneumonia was strongly associated with posttransplant survival and represents an opportunity for improvement. By truly understanding the outcomes of elderly and frail recipients, transplant centers can improve outcomes for these higher-risk recipients.

Dabigatran Reversal With Idarucizumab in 2 Patients With Portal Vein Thrombosis Undergoing Orthotopic Liver Transplantation.

There are limited data to guide the use of anticoagulation in cirrhotic patients prior to liver transplantation especially when using direct oral anticoagulants. In this article, we present 2 cases. The first is a 42-year-old male with cirrhosis complicated by portal vein thrombosis (PVT) treated with dabigatran who underwent orthotopic liver transplantation without complication. The second case is a 65-year-old man with alcoholic cirrhosis complicated by PVT treated with dabigatran who underwent orthotopic liver transplantation and required reoperation for surgical bleeding. Both patients were treated with dabigatran's reversal agent idarucizumab prior to incision. In this case series, we discuss the treatment of cirrhotic patients with various anticoagulants, considerations for anticoagulant selection and reversal prior to liver transplant, and questions for future investigation.

Extinguishing burnout: National analysis of predictors and effects of burnout in abdominal transplant surgery fellows.

Burnout among surgeons has been attributed to increased workload and decreased autonomy. Although prior studies have examined burnout among transplant surgeons, no studies have evaluated burnout in abdominal transplant surgery fellows. The objective of our study was to identify predictors of burnout and understand its impact on personal and patient care during fellowship. A survey was sent to all abdominal transplant surgery fellows in an American Society of Transplant Surgeons-accredited fellowship. The response rate was 59.2% (n = 77) and 22.7% (n = 17) of fellows met criteria for burnout. Fellows with lower grit scores were more likely to exhibit burnout compared with fellows with higher scores (3.6 vs 4.0, P = .026). Those with burnout were more likely to work >100 hours per week (58.8% vs 27.6%, P = .023), have severe work-related stress (58.8% vs 22.4%, P = .010), consider quitting fellowship (94.1% vs 20.7%, P < .001), or make a medical error (35.3% vs 5.2%, P = .003). This national analysis of abdominal transplant fellows found that burnout rates are relatively low, but few fellows engage in self-care. Personal and program-related factors attribute to burnout and it has unacceptable effects on patient care. Transplant societies and fellowship programs should develop interventions to give fellows tools to prevent and combat burnout.

Detection of early allograft dysfunction at 30 min of reperfusion in liver transplantation: An intraoperative diagnostic tool with real time assessment of graft function.

INTRODUCTION: During the anhepatic phase of liver transplantation (LT), fibrinolytic activity increases, since the liver clears tissue plasminogen activator (tPA). We hypothesize that patients who fail to reduce fibrinolytic activity following graft reperfusion will have an increased rate of early allograft dysfunction (EAD). METHODS: Assessment of fibrinolysis in liver transplant recipients was quantified with thrombelastography (TEG) LY30. Changes in LY30 were assessed after graft reperfusion. The 30-min post-reperfusion LY30 was subtracted from the anhepatic LY30 quantifying fibrinolytic changes (delta-LY30). RESULTS: Seventy-three primary LT patients were included in the analysis. Receiver operating characteristic curve (ROC) analysis identified an inflection point of delta-LY30-5.3% as a risk factor for EAD. EAD occurred in 44% of these patients compared to 5% in high delta-LY30 (p = 0.002). CONCLUSION: LT recipients that develop hyperfibrinolysis who fail to reduce fibrinolytic activity 30 min after graft reperfusion had an EAD rate 8-fold higher than patients who had a large reduction in LY30 following reperfusion.

A clinical coagulopathy score concurrent with viscoelastic testing defines opportunities to improve hemostatic resuscitation and enhance blood product utilization during liver transplantation.

BACKGROUND: An NIH clinical coagulopathy score has been devised for trauma patients, but no such clinical score exists in transplantation surgery. We hypothesize that that this coagulopathy score can effectively identify laboratory defined coagulopathy during liver transplantation and correlates to blood product utilization. METHODS: TEGs were performed and coagulopathy scores (1, normal bleeding - 5, diffuse coagulopathic bleeding) were assigned by the surgeons at 5 intra-operative time points. Blood products used during the case were recorded between time points. Statistical analyses were performed to identify correlations between coagulopathy scores, TEG-detected abnormalities, and blood product utilization. RESULT: Transfusions rarely correlated with the appropriate TEG measurements of coagulation dysfunction. Coagulopathy score had significant correlation to various transfusions and TEG-detected coagulopathies at multiple points during the case. High aggregate coagulopathy scores identified patients receiving more transfusions, re-operations, and longer hospital stays CONCLUSION: The combination of viscoelastic testing and a standardized clinical coagulopathy score has the potential to optimize transfusions if used in tandem as well as standardize communication between surgery and anesthesia teams about clinically evident coagulopathy.

The use of thromboelastography to assess post-operative changes in coagulation and predict graft function in renal transplantation.

BACKGROUND: End stage renal disease (ESRD) is associated with elevated fibrinogen levels and fibrinolysis inhibition. However, there is a paucity of data on how renal transplantation impacts coagulation. we hypothesize that renal transplantation recipients with good functioning grafts will have improved fibrinolytic activity following surgery. METHODS: Kidney recipients were analyzed pre-operatively and on post-operative day 1(POD1) using three different TEG assays with and without two concentration of tissue-plasminogen activator (t-PA). TEG indices and percent reduction in creatinine from pre-op to POD1 were measured, with >50% defining "good" graft function. Follow up was done at 6, 12, and 24 months. RESULTS: Percent lysis(LY30) on POD1 the t-PA TEG was significantly correlated to change creatinine from pre-op to POD-1(p = 0.006). A LY30 ≥ 23% was associated with good early graft function, and lower creatinine at 24-months(p = 0.028) compared to recipients with low POD1 LY30. CONCLUSIONS: Post-operative tPA-TEG LY30 is associated with favorable early and late outcomes in kidney transplant.

Reverse epidemiology and the obesity paradox for patients with chronic kidney disease: a Markov decision model.

BACKGROUND: Obesity has been associated with both increased progression of chronic kidney disease (CKD) as well as with a paradoxical improvement in survival among end-stage renal disease patients undergoing hemodialysis. As such, the optimal weight management strategy for obese CKD patients remains unclear. OBJECTIVE: To estimate the outcomes of obese, CKD stage 3b patients after 3 weight loss interventions, including medical weight management, sleeve gastrectomy (SG), and Roux-en-Y gastric bypass (RYGB), were followed to determine which strategy optimizes long-term survival. SETTING: University hospital, Aurora, Colorado. METHODS: A decision analytic Markov state transition model was created to simulate the life of 30,000 obese patients with CKD stage 3b, as they progressed to end-stage renal disease, transplantation, and death. Life expectancy after conservative medical weight management, RYGB, and SG were estimated. Base case patients were defined as being 50 years old and having a preintervention BMI of 40 kg/m2. Sensitivity analysis of initial BMI was performed. All Markov parameters were extracted from literature review. RESULTS: RYGB and SG were associated with improved survival for patients with preintervention body mass index of >38 kg/m2. Compared with conservative weight management, base case patients who underwent RYGB gained 10.6 months of life, and gained 8.3 months of life after SG. CONCLUSIONS: Balancing progression of CKD with improved survival on end-stage renal disease for obese patients requires selective use of weight management strategies. RYGB and SG improved survival for CKD patients with Class II and III obesity, but not for patients with Class I obesity. As such, aggressive weight loss interventions should be reserved for patients with Class II and III obesity, while more conservative methods should be offered to those with Class I obesity.

Sleeve Gastrectomy Compared with Gastric Bypass for Morbidly Obese Patients with End Stage Renal Disease: a Decision Analysis.

INTRODUCTION: The use of bariatric surgery has increased for morbidly obese patients with end stage renal disease (ESRD) for whom listing on the waitlist is often restricted until a certain BMI threshold is achieved. Effective weight loss for this population improves access to life-saving renal transplantation. However, it is unclear whether sleeve gastrectomy (SG) vs Roux-en-Y gastric bypass (RYGB) is a more effective therapy for these patients. METHODS: A decision analytic Markov state transition model was created to simulate the life of morbidly obese patients with ESRD who were deemed ineligible to be waitlisted for renal transplantation unless they achieved a BMI less than 35 kg/m2. Life expectancy following weight management (MWM), RYGB, and SG were estimated. Base case patients were defined as having a pre-intervention BMI of 45 kg/m2. Sensitivity analysis of initial BMI was performed. Markov parameters were extracted from literature review. RESULTS: RYGB improved survival compared with SG and MWM. RYGB patients had higher rates of transplantation, leading to improved mean long-term survival. Base case patients who underwent RYGB gained 1.3 additional years of life compared with patient's who underwent SG and 2.6 additional years of life compared with MWM. CONCLUSIONS: RYGB improves access to renal transplantation and thereby increases long-term survival compared with SG and MWM. The use of SG may be incongruent with the goal of improving access to renal transplantation for morbidly obese patients.

Offspring Versus Nonoffspring to Parent Living Donor Liver Transplantation: Does Donor Relationship Matter?

BACKGROUND: Offspring (donor) to parent (recipient) transplant is the most common form of living donor liver transplant in the United States. In kidney transplantation, it has been suggested that female recipients of offspring living donor kidney allografts have inferior outcomes. It is unknown whether such a phenomenon also occurs following living donor liver transplantation. METHODS: A retrospective analysis was completed of recipients of a living donor liver transplant from January 1998 to January 2018 in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database. Patients were grouped as having received a living donor liver allograft from either an offspring or a nonoffspring, with exactly 3 HLA matches, as would be expected between an offspring and parent. Graft and patient survival were analyzed using Cox proportional hazards modeling. RESULTS: A total of 279 offspring to parent and 241 nonoffspring donor liver transplants were included in the analysis. Female recipients of offspring liver allografts had both inferior 10-year graft (52% versus 72%; P < 0.001) and patient survival (52% versus 81%; P < 0.001) compared with female recipients of nonoffspring allografts. No such difference in outcomes was discovered among male recipients. A stratified analysis of sex of offspring donors to female recipients demonstrated that donor male gender was associated with graft failure (HR = 2.87; P = 0.04) and mortality (hazard ratio = 3.89; P = 0.03). Again, this association was not seen with male recipients. CONCLUSIONS: Among female recipients, offspring to parent living donor liver transplantation yields inferior long-term graft and patient survival. Furthermore, among offspring donors, male sex was strongly associated with inferior outcomes. These findings have significant implications for donor selection.

A Vascular Anastomosis Simulation Can Provide a Safe and Effective Environment for Resident Skills Development.

OBJECTIVE: Vascular anastomoses are complex surgical procedures, performed in time-sensitive circumstances, making intraoperative teaching more challenging. We sought to evaluate whether a vascular anastomosis simulation was effective in developing resident skills. DESIGN, SETTING, PARTICIPANTS: General surgery residents participated in a vascular anastomosis simulation for 1 to 2hours during their transplant rotation. An attending transplant surgeon at the University of Colorado guided the resident through end-to-end and end-to-side anastomoses using bovine carotid artery (Artegraft). The residents completed a presimulation and postsimulation survey which quantitated their confidence. They also completed the MiSSES scale, which assessed the validity of the simulation. RESULTS: Twenty residents participated in the simulation and completed the surveys. The residents reported increased understanding in how to set up an end-to-end anastomosis and an end-to-side anastomosis (p = 0.001 and p = 0.009, respectively). They reported increased ability to suture, forehand and backhand with a Castro-Viejo needle driver (both p < 0.001). The residents reported increased ability to manipulate the needle (p = 0.006), and increased ability to manipulate tissue without causing trauma (p = 0.021). They reported increased confidence in tying a surgical knot with 6-0 Prolene and in operating while wearing loupes (p = 0.002, and p < 0.001, respectively). Overall, the residents reported increased confidence when asked to perform part of a vascular anastomosis in the operating room (p < 0.001). Seventeen residents completed the MiSSES scale with median scores of "somewhat agree" to "strongly agree" on all domains of the scale. CONCLUSIONS: The use of a simple, inexpensive vascular anastomosis simulation is an effective and safe environment to improve residents' surgical skills and the residents felt that the simulation was valid.