Frasco, Peter E.

Background: Normothermic machine perfusion (NMP) may reduce preservation injury in donation-after-circulatory-death (DCD) liver transplantation, but its association with patient-centered recovery and longer-term graft survival remains uncertain. Study Design: We retrospectively analyzed 306 consecutive adult DCD liver transplant recipients at a single center from January 2019 through December 2022, comparing NMP (n=95) with static cold storage (SCS; n=211). The primary endpoint was days alive and out of hospital at 365 days (DAOH365). Quasi-Poisson regression evaluated factors associated with DAOH365, and Cox regression evaluated graft survival. Propensity-matched and calendar-year sensitivity analyses assessed measured confounding. Results: Median DAOH365 was 357.0 (352.0, 360.0) days with NMP versus 353.0 (336.0, 359.0) with SCS (p<0.001), but preservation strategy was not independently associated with DAOH365 (adjusted rate ratio 1.02; p=0.331). NMP recipients had less early allograft dysfunction (35.8% vs 59.7%; p<0.001), ischemic cholangiopathy (4.2% vs 23.7%; p<0.001), and retransplantation within 2 years (0.0% vs 6.6%; p=0.007). Two-year patient survival did not differ significantly. NMP was associated with improved twoF-year graft survival (HR 2.9, 95% CI 1.23–6.87; p=0.015), an association maintained in propensity-matched and calendar-year sensitivity analyses. Adjusted total 1-year costs did not differ (p=0.512). Conclusions: In this single-center DCD cohort, NMP was associated with superior 2-year graft survival but not independently with DAOH365. These hypothesis-generating findings support multicenter prospective evaluation of NMP using both graft survival and patient-centered recovery endpoints.

BACKGROUND: Although most transplant centers preferentially offer minimally invasive approaches to donor nephrectomies, there remains less standardization specific to the kidney extraction site. This study aimed to evaluate incisional hernia occurrence in living kidney donors based on kidney extraction site location. STUDY DESIGN: This was a retrospective study of all donors who underwent minimally invasive living donor nephrectomies at the Mayo Clinic Arizona between 2011 and 2023 with a 2-year external validation cohort from Mayo Clinic Florida and Mayo Clinic Minnesota. The cohort was divided into 2 groups based on the kidney extraction site type: midline infraumbilical and Pfannenstiel. RESULTS: In the primary cohort, incisional hernia occurrence was observed in 1.2% of donors with an infraumbilical midline kidney extraction site compared with 0.1% with a Pfannenstiel extraction site (p = 0.04). Donors with an infraumbilical midline kidney extraction site were more likely to be men (50.8% vs 23.3%, p < 0.0001), have a higher BMI (mean 27.2 vs 26 kg/m2, p < 0.0001), and have current or former tobacco use (p = 0.002). There were no differences in incisional hernia occurrence when comparing minimally invasive surgical techniques (p = 0.52). In the external validation cohort, hernia occurrence was observed in 4.5% of donors with a midline incision compared with 0.0% with a Pfannenstiel incision (p = 0.09). Using combined data from the 3 sites, the use of a Pfannenstiel incision as the extraction site was associated with significantly lower odds of developing a hernia compared with the infraumbilical midline incision (odds ratio 0.06, 95% CI 0.008 to 0.456). CONCLUSIONS: Although the risk of hernia in living kidney donors is generally low, the use of a Pfannenstiel incision for kidney extraction appears to offer an additional incremental reduction in risk.

Importance Normothermic machine perfusion (NMP) has been shown to reduce peritransplant complications. Despite increasing NMP use in liver transplant (LT), there is a scarcity of real-world clinical experience data. Objective To compare LT outcomes between donation after brain death (DBD) and donation after circulatory death (DCD) allografts preserved with NMP or static cold storage (SCS). Design, Setting, and Participants This single-center, retrospective observational cohort study included all consecutive adult LTs performed between January 2019 and December 2023 at the Mayo Clinic in Arizona. Data analysis was performed between February 2024 and June 2024. Outcomes of DBD-SCS, DBD-NMP, DCD-SCS, and DCD-NMP transplants were compared. Exposure DBD and DCD livers preserved on NMP or SCS. Main Outcomes and Measures The primary outcomes were early allograft dysfunction (EAD), intraoperative transfusion, and post-LT hospital resource use, including length of stay (LOS) and readmissions. Secondary outcomes included acute kidney injury (AKI) and 1-year graft and patient survival. Results A total of 1086 LTs were included in the following 4 groups: DBD-SCS (n = 480), DBD-NMP (n = 63), DCD-SCS (n = 264), and DCD-NMP (n = 279). Among LT recipients, median (IQR) age was 60.0 years (52.0-66.0); 399 LT recipients (36.7%) were female. DCD-NMP had the lowest EAD rate (17.5%), followed by DCD-SCS (50.0%), DBD-NMP (36.8%), and DBD-SCS (27.3%) ( P &amp;lt; .001). DCD-NMP had the lowest intraoperative transfusion requirement compared to all other groups. Hospital and intensive care unit (ICU) LOS were shortest in DCD-NMP (median [IQR] hospital LOS, 5.0 days [4.0-7.0]; P = .01; median [IQR] ICU LOS, 1.5 days [1.2-3.1]; P = .01). One-year cumulative readmission probability was 86% lower for DCD-NMP vs DCD-SCS (95% CI, 0.09-0.22; P &amp;lt; .001) and 53% lower for DBD-NMP vs DBD-SCS (95% CI, 0.26-0.87; P &amp;lt; .001). AKI events were lower in DCD-NMP (31.1%) vs DCD-SCS (47.4%) ( P = .001). Compared to SCS, the NMP group had a 78% overall reduction in graft failure (hazard ratio [HR], 0.22; 95% CI, 0.10-0.49; P &amp;lt; .001). For those receiving DCD allografts, the risk reduction was even more pronounced, with an 87% decrease in graft failure (HR, 0.13; 95% CI, 0.05-0.33; P &amp;lt; .001). NMP was significantly protective from patient mortality vs SCS (HR, 0.31; 95% CI, 0.12-0.80; P = .02). Conclusions and Relevance In this observational high-volume cohort study, NMP significantly improved LT clinical outcomes and reduced hospital resource use, especially in DCD allografts. NMP may enhance access to LT by addressing the challenges historically linked with DCD liver use.

BACKGROUND: During orthotopic liver transplantation, allograft reperfusion is a dynamic point in the operation and often requires vasoactive medications and blood transfusions. Normothermic machine perfusion (NMP) of liver allografts has emerged to increase the number of transplantable organs and may have utility during donation after circulatory death (DCD) liver transplantation in reducing transfusion burden and vasoactive medication requirements. METHODS: This is a single-center retrospective study involving 226 DCD liver transplant recipients who received an allograft transported with NMP (DCD-NMP group) or with static cold storage (DCD-SCS group). Veno-venous bypass was not used in any patients. Infusion doses of norepinephrine, epinephrine, and vasopressin as well as bolus doses of vasoactive medications during reperfusion were recorded. Blood component therapy was recorded according to phase of liver transplantation and during the first 24 hours postprocedure. RESULTS: A total of 103 recipients in the DCD-NMP group and 123 patients in the DCD-SCS group were included. Post-reperfusion syndrome (PRS) incidence was reduced in the DCD-NMP group compared to the DCD-SCS group (10.7% [95% confidence interval, CI, 5.5%–18.3%] vs 42.3% [95% CI, 33.4%–51.5%]; P < .001). During the reperfusion period, patients in the DCD-SCS group required increased bolus doses of epinephrine and vasopressin compared to the DCD-NMP group (24.6 vs 7.5 µg; P < .001) and (5.4 vs 2.4 units; P < .001), respectively. The DCD-SCS group received a higher infusion dose of epinephrine during anhepatic phase, at reperfusion, and up to 90 minutes after reperfusion. In the postreperfusion period, there were significant increases in the transfusion of red blood cells (RBCs; 5.3 vs 3.7 units; P = .006), fresh frozen plasma (FFP; 3.4 vs 1.9 units; P < .001), cryoprecipitate (2.7 vs 1.8 pooled units; P = .015) and platelets (0.9 vs 0.4 units; P = .008) in the DCD-SCS group compared to the DCD-NMP group. During the first 24 hours postprocedure, transfusion of RBCs, FFP, and cryoprecipitate in the DCD-SCS group was increased compared to the DCD-NMP group ([2.6 vs 1.7 units; P = .028], [1.6 vs 0.8 units; P < .001], [1.5 vs 0.9 pooled units; P = .031]) respectively. Administration of tranexamic acid was more frequent in the DCD-SCS group during the post-reperfusion period compared to the DCD-NMP group (13% [95% CI, 5.7%–17.4%] vs 3.9% [95% CI, 1.1%–9.6% 95%]; P = .018). CONCLUSIONS: In DCD liver transplantation, use of NMP was associated with reduced incidence of PRS and decreased vasopressor and inotrope requirements at the time of allograft reperfusion compared to using SCS. Additionally, NMP was associated with reduced transfusion of all blood product components as well as antifibrinolytic agent administration in the post-reperfusion period. Reduced transfusion burden in the DCD-NMP group also occurred during the first 24 hours posttransplant.

The estimation of surgical blood loss is routinely performed during and after surgical procedures and has morbidity and mortality implications related to the risk of under- and over-resuscitation. The strategies for estimating surgical blood loss include visual estimation, the gravimetric method, the colorimetric method, formula-based methods, and other techniques (e.g., cell salvage). Currently, visual estimation continues to be the most widely used technique. In addition, unique considerations exist when these techniques are applied to various clinical settings such as massive transfusion, cardiac surgery, and obstetrics. Ultimately, when using estimated surgical blood loss to guide perioperative fluid management and transfusion thresholds, it is also important to mitigate the risks associated with resuscitation by targeting a goal-directed fluid therapy approach by utilizing markers of fluid-responsiveness to optimize stroke volume (cardiac output) and delivery of oxygen.

The use of normothermic machine perfusion (NMP) over static cold storage in liver transplantation has been shown to reduce posttransplant risks of early allograft dysfunction, primary nonfunction, and ischemic cholangiopathy, and its increasing use has played a role in the expanded utilization of marginal livers. While studies have demonstrated improved clinical outcomes using NMP over static cold storage preservation, real-time intraoperative data reflecting the quality and viability of NMP livers is limited. This retrospective, single-center study compared NMP versus static cold storage livers in first-time recipients of liver transplants through the evaluation of synthetic coagulation function as measured by thromboelastography and conventional coagulation testing. Secondarily, transfusion utilization between the 2 cohorts was reviewed. One hundred eighty-six recipients of liver transplants receiving allografts from donors after circulatory death were included in the study, of which 99 (53%) allografts were preserved in static cold storage, and 87 (47%) allografts were placed on the TransMedics Organ Care System. Study findings showed NMP livers supported with the TransMedics Organ Care System were associated with increased synthetic coagulation function and less excess fibrinolysis in the postreperfusion period compared to static cold storage livers, and that these findings were better reflected in real-time with thromboelastography monitoring versus conventional coagulation testing. Following reperfusion, there was a significant decrease in the transfusion of blood products in the NMP group compared with that in the static cold storage group. Overall, we determined that the use of intraoperative thromboelastography can provide real-time data to assess one aspect of reperfusion liver quality and viability.

OBJECTIVES Transesophageal echocardiography (TEE) is being increasingly utilized during orthotopic liver transplantation to guide perioperative management. Obstacles of improving TEE utilization include the challenge of becoming familiar with the TEE machine, optimizing TEE images, and translating skills acquired in didactic or simulator center-based training into clinical use. METHODS In an effort to expand TEE utilization and improve workflow among the liver transplantation (LT) anesthesiologists at our institution, a LT-specific TEE guide was created to serve as a reference and educational tool during LT. A 26-question survey was distributed to all LT anesthesiologists before and 6 months after implementation of the LT-specific TEE guide. RESULTS All seven LT anesthesiologists completed the survey questions during the study period. No statistically significant difference was detected in participant-reported confidence in optimizing targeted TEE views, performing technical aspects of the exam, navigating the knobs on the TEE machine, or in ability to identify abnormal cardiac pathology during the study period. One participant became basic-TEE certified during the study period. CONCLUSIONS Implementing a liver transplant-specific TEE guide is a strategy to expand TEE utilization, encourage longitudinal TEE education and reinforce concepts learned from hands-on education sessions; however, we did not detect a difference in participant-reported confidence of performing a TEE exam, ability to identify abnormal cardiac pathology or altering workflow. Further studies with larger sample sizes will be needed to evaluate the effectiveness of a LT-specific TEE guide.

The continued citation of retracted publications from the medical literature is a well-known and persistent problem. We describe the contexts of ongoing citations to manuscripts that have been retracted from a selection of anesthesiology journals. We also examine how bibliographic databases and publisher websites document the retracted status of these manuscripts. The authors performed an analysis of retracted publications from anesthesiology journals using the Retraction Watch database. We then examined how the retraction information was displayed on bibliographic databases, search engines, and publisher websites. The primary outcome was the context of continued citation after retraction of flawed publications within the specialty of anesthesiology. Secondary outcomes included comparison of the documentation, bibliographic databases, search engines, and publisher websites used in identifying the retracted status of these publications and provision of access to the respective retraction notices. A total of 245 original publications were retracted over a 28-year period from 9 anesthesiology journals. PubMed, compared to the other databases and search engines, was the most consistent (98.8%) in documenting the retracted status of the publications examined, as well as providing a direct link to the retraction notice. From the 211 publications retracted before January 2020, there were 1307 postretraction citations accessed from Scopus. The median number of postretraction citations was 3.5 (range, 0–88, with at least 1 citation in 164 publications) in Scopus. Of the postretraction citations, 80% affirmed the validity of the retracted publications, while only 5.2% of citations acknowledged the retraction or misconduct. In 10.2% of the citations from original research studies, retracted manuscripts appeared to influence the decision to pursue or the methods used in subsequent original research studies. The frequency of citation of the 15 most cited retracted publications declined in a similar pattern during the 10 years after retraction. Citation of manuscripts retracted from anesthesiology journals remains a common occurrence. Technological innovations and application of standards for handling retracted publications, as suggested by coalitions of researchers across the spectrum of scientific investigation, may serve to reduce the persistence of this error.