Valuing improvements in the ecological integrity of local and regional waters using the biological condition gradient.

Scientific knowledge related to quantifying the monetized benefits for landscape-wide water quality improvements does not meet current regulatory and benefit-cost analysis needs in the United States. In this study we addressed this knowledge gap by incorporating the Biological Condition Gradient (BCG) as a water quality metric into a stated preference survey capable of estimating the total economic value (use and nonuse) for aquatic ecosystem improvements. The BCG is grounded in ecological principles and generalizable and transferable across space. Moreover, as the BCG translates available data on biological condition into a score on a 6-point scale, it provides a simple metric that can be readily communicated to the public. We applied our BCG-based survey instrument to households across the Upper Mississippi, Ohio, and Tennessee river basins and report values for a range of potential improvements that vary by location, spatial scale, and the scope of the water quality change. We found that people are willing to pay twice as much for an improvement policy that targets their home watershed (defined as a four-digit hydrologic unit) versus a more distant one. We also found that extending the spatial scale of a local policy beyond the home watershed does not generate additional benefits to the household. Finally, our results suggest that nonuse sources of value (e.g., bequest value, intrinsic aesthetic value) are an important component of overall benefits.

Valuing water quality in the United States using a national dataset on property values.

High-quality water resources provide a wide range of benefits, but the value of water quality is often not fully represented in environmental policy decisions, due in large part to an absence of water quality valuation estimates at large, policy relevant scales. Using data on property values with nationwide coverage across the contiguous United States, we estimate the benefits of lake water quality as measured through capitalization in housing markets. We find compelling evidence that homeowners place a premium on improved water quality. This premium is largest for lakefront property and decays with distance from the waterbody. In aggregate, we estimate that 10% improvement of water quality for the contiguous United States has a value of $6 to 9 billion to property owners. This study provides credible evidence for policymakers to incorporate lake water quality value estimates in environmental decision-making.

A practical guide to real-world implementation of pre-emptive therapy for Cytomegalovirus disease prevention in high-risk seronegative liver transplant recipients with seropositive donors.

The Comparison of Antiviral Preventative Strategies In Liver Transplant (CAPSIL) study showed pre-emptive therapy (PET) to be superior to antiviral prophylaxis for Cytomegalovirus (CMV) disease prevention in high-risk CMV seronegative liver transplant recipients (LTRs) with seropositive donors (D+R-). Despite the statistical superiority of PET over prophylaxis in research settings, PET is perceived as a logistically more complex strategy that requires careful coordination of weekly CMV PCR testing, prompt initiation of CMV antivirals upon viremia detection, and timely cessation of antivirals following viremia resolution. Transplant centers may be hesitant to use PET for CMV disease prevention in D+R- LTRs out of concern that PET coordination is not feasible in clinical practice. We recently described our experience using PET in CMV D+R- LTRs in a real-world setting, and found it to be as effective for CMV disease prevention as PET performed as part of a clinical trial. Here, we describe a systematic approach for PET implementation in real-world settings and provide practical tools to address anticipated challenges. This framework can support transplant programs in overcoming logistical barriers to PET and incorporating an evidence-based and cost-effective CMV prevention strategy into routine care for high-risk CMV D+R- LTRs.

Integrated assessment modeling reveals near-channel management as cost-effective to improve water quality in agricultural watersheds.

Despite decades of policy that strives to reduce nutrient and sediment export from agricultural fields, surface water quality in intensively managed agricultural landscapes remains highly degraded. Recent analyses show that current conservation efforts are not sufficient to reverse widespread water degradation in Midwestern agricultural systems. Intensifying row crop agriculture and increasing climate pressure require a more integrated approach to water quality management that addresses diverse sources of nutrients and sediment and off-field mitigation actions. We used multiobjective optimization analysis and integrated three biophysical models to evaluate the cost-effectiveness of alternative portfolios of watershed management practices at achieving nitrate and suspended sediment reduction goals in an agricultural basin of the Upper Midwestern United States. Integrating watershed-scale models enabled the inclusion of near-channel management alongside more typical field management and thus directly the comparison of cost-effectiveness across portfolios. The optimization analysis revealed that fluvial wetlands (i.e., wide, slow-flowing, vegetated water bodies within the riverine corridor) are the single-most cost-effective management action to reduce both nitrate and sediment loads and will be essential for meeting moderate to aggressive water quality targets. Although highly cost-effective, wetland construction was costly compared to other practices, and it was not selected in portfolios at low investment levels. Wetland performance was sensitive to placement, emphasizing the importance of watershed scale planning to realize potential benefits of wetland restorations. We conclude that extensive interagency cooperation and coordination at a watershed scale is required to achieve substantial, economically viable improvements in water quality under intensive row crop agricultural production.

Real-world effectiveness of preemptive therapy (PET) for cytomegalovirus (CMV) disease prevention in CMV high-risk donor seropositive/recipient seronegative (D+R-) liver transplant recipients (LTxR).

BACKGROUND: Despite superiority of preemptive therapy (PET) compared to universal prophylaxis for prevention of cytomegalovirus (CMV) disease in the CAPSIL randomized trial among CMV D+R- liver transplant recipients (LTxRs), real-world effectiveness may be lower because of logistical concerns about feasibility of PET. METHODS: We retrospectively assessed PET as standard clinical care at a single transplant center among 50 consecutive adult CMV D+R- LTxRs undergoing a first liver transplant between 4/4/2019 and 5/18/2021 and compared outcomes and adherence to those randomized to PET in the CAPSIL study (N = 100). The primary outcome was CMV disease and secondary outcomes were biopsy-confirmed acute allograft rejection, retransplant, invasive fungal infections, and death, all assessed by 1-year post-transplant. Exploratory outcomes included virologic parameters and measures of adherence to protocol-specified CMV qPCR monitoring. RESULTS: Baseline characteristics were similar between groups. The cumulative incidence of CMV disease at 1-year post-transplant was 4/50 (8%) versus 9/100 (9%) in the real-world and CAPSIL cohorts, respectively, p = 1.0. The rate of breakthrough CMV disease during the 100-day PET period was low (2/50 [4%]) and similar to the PET cohort from the CAPSIL study (3/100 [3%]).  All secondary and exploratory outcomes were not significantly different between the real-world and CAPSIL PET cohorts. CONCLUSIONS: In this first reported study of real-world PET, the feasibility and effectiveness for CMV disease prevention and for other clinical outcomes in CMV D+R- LTxRs were similar to those reported with PET in a clinical trial. Additional studies to confirm feasibility and generalizability in other settings are warranted.

Conservation cobenefits from air pollution regulation: Evidence from birds.

Massive wildlife losses over the past 50 y have brought new urgency to identifying both the drivers of population decline and potential solutions. We provide large-scale evidence that air pollution, specifically ozone, is associated with declines in bird abundance in the United States. We show that an air pollution regulation limiting ozone precursors emissions has delivered substantial benefits to bird conservation. Our estimates imply that air quality improvements over the past 4 decades have stemmed the decline in bird populations, averting the loss of 1.5 billion birds, ∼20% of current totals. Our results highlight that in addition to protecting human health, air pollution regulations have previously unrecognized and unquantified conservation cobenefits.

Deceased donor kidneys are discarded at higher rates when labeled as high kidney donor profile index.

The kidney donor risk index (KDRI) and percentile conversion, kidney donor profile index (KDPI), provide a continuous measure of donor quality. Kidneys with a KDPI >85% (KDPI85 ) are referred to as "high KDPI." The KDPI85 cutoff changes every year, impacting which kidneys are labeled as KDPIHIGH . We examine kidney utilization around the KDPI85 cutoff and explore the "high KDPI" labeling effect. KDRI to KDPI Mapping Tables from 2012 to 2020 were used to determine the yearly KDRI85 value. Organ Procurement and Transplantation Network data was used to calculate discard rates and model organ use. KDRI85 varied between 1.768 and 1.888. In a multivariable analysis, kidney utilization was lower for KDPI 86% compared with KDPI 85% kidneys (p = .046). Kidneys with a KDRI between 1.785-1.849 were classified as KDPIHIGH in the years 2015-2017 and KDPILOW in the years 2018-2020. The discard rate was 44.9% when labeled as KDPIHIGH and 39.1% when labeled as KDPILOW (p < .01). For kidneys with the same KDRI, the high KDPI label is associated with increased discard. We should reconsider the appropriateness of the "high KDPI" label.

The low but uncertain measured benefits of US water quality policy.

US investment to decrease pollution in rivers, lakes, and other surface waters has exceeded $1.9 trillion since 1960, and has also exceeded the cost of most other US environmental initiatives. These investments come both from the 1972 Clean Water Act and the largely voluntary efforts to control pollution from agriculture and urban runoff. This paper reviews the methods and conclusions of about 20 recent evaluations of these policies. Surprisingly, most analyses estimate that these policies' benefits are much smaller than their costs; the benefit-cost ratio from the median study is 0.37. However, existing evidence is limited and undercounts many types of benefits. We conclude that it is unclear whether many of these regulations truly fail a benefit-cost test or whether existing evidence understates their net benefits; we also describe specific questions that when answered would help eliminate this uncertainty.

Transplant tourism complicated by life-threatening New Delhi metallo-ß-lactamase-1 infection.

Transplant tourism, which is the practice of traveling to other countries for transplant, continues to be a major problem worldwide. We describe a patient who traveled to Pakistan and underwent commercial kidney transplant. He developed life-threatening infections from New Delhi metallo-ß-lactamase-1-producing Enterobacter cloacae and Rhizopus oryzae, resulting in a necrotizing kidney allograft infection and subsequent external iliac artery rupture. He survived after a prolonged course of nonstandardized antimicrobial therapy, including a combination of aztreonam and ceftazidime-avibactam, and aggressive surgical debridement with allograft nephrectomy. The early timing of infection with these unusual organisms localized to the allograft suggests contamination and substandard care at the time of transplant. This case highlights the challenges of caring for these infections and serves as a cautionary tale for the potential complications of commercial transplant tourism.

Living Donation Versus Donation After Circulatory Death Liver Transplantation for Low Model for End-Stage Liver Disease Recipients.

In this era of organ scarcity, living donor liver transplantation (LDLT) is an alternative to using deceased donors, and in Western countries, it is more often used for recipients with low Model for End-Stage Liver Disease (MELD) scores. We sought to compare the patient survival and graft survival between recipients of liver transplantation from living donors and donation after circulatory death (DCD) donors in patients with low MELD scores. This is a retrospective cohort analysis of adult liver transplant recipients with a laboratory MELD of ≤20 who underwent transplantation between January 1, 2003 and March 31, 2016. Recipients were categorized by donor graft type (DCD or LDLT), and recipient and donor characteristics were compared. Ten-year patient and graft survival curves were calculated using Kaplan-Meier analyses, and a mixed-effects model was performed to determine the contributions of recipient, donor, and center variables on patient and graft survival. There were 36,705 liver transplants performed: 32,255 (87.9%) from DBD donors, 2166 (5.9%) from DCD donors, and 2284 (6.2%) from living donors. In the mixed-effects model, DCD status was associated with a higher risk of graft failure (relative risk [RR], 1.27; 95% confidence interval [CI], 1.16-1.38) but not worse patient survival (RR, 1.27; 95% CI, 0.96-1.67). Lower DCD center experience was associated with a 1.21 higher risk of patient death (95% CI, 1.17-1.25) and a 1.13 higher risk of graft failure (95% CI, 1.12-1.15). LDLT center experience was also predictive of patient survival (RR, 1.03; 95% CI, 1.02-1.03) and graft failure (RR, 1.05; 95% CI, 1.05-1.06). In conclusion, for liver transplant recipients with low laboratory MELD, LDLT offers better graft survival and a tendency to better patient survival than DCD donors.

Follow-up imaging of traumatic vertebral artery dissections is unnecessary in asymptomatic patients.

OBJECTIVE: Routine computed tomography (CT) imaging in trauma patients has led to increased recognition of blunt vertebral artery injuries (BVIs). We sought to determine the prevalence of strokes, injury progression, and need for intervention in patients with BVI. METHODS: Consecutive patients presenting with BVI during 2 years were identified from the institutional trauma registry. Inpatient records, imaging studies, and follow-up data were reviewed in detail from the electronic medical record. RESULTS: There were 76 BVIs identified in 70 patients (64% male; mean age, 47 ± 19 years); bilateral injuries occurred in 6 patients. Five patients who arrived at the hospital intubated had evidence of posterior circulation infarcts on admission CT, whereas one additional patient had evidence of a posterior circulation infarct attributed to complications of late spinal surgery. Four of the five patients with infarcts on admission CT survived to discharge, but only one had residual stroke symptoms. Minor (grade 1 or grade 2) injuries occurred in 25 (36%) patients; severe (grade 3 or grade 4) injuries occurred in 45 (64%). Twelve patients died of associated injuries (eight with severe BVI, four with minor BVI). Stepwise logistic regression analysis selected age (odds ratio, 1.14; confidence interval, 1.04-1.25; P < .001) and intubation on arrival (odds ratio, 450.4; confidence interval, 17.41-1645.51; P < .001) as independent predictors of hospital stroke and death. Of the 58 surviving to discharge, 31 (53%) returned for follow-up CT scans. Six of 10 (60%) patients with minor injuries had resolution or improvement compared with 3 of 21 (14%) with severe injuries (P = .027). One patient (10%) with a minor BVI and two patients (10%) with severe BVI had radiologic progression, but none were clinically significant. During a mean follow-up of 15 ± 13 months, none of the study patients had treatment (surgical or interventional) for BVI, and there were no delayed strokes. Only five patients in this series had vertebral pseudoaneurysms, which limits conclusions about this type of BVI. CONCLUSIONS: These data suggest that BVI-related strokes are present at the time of admission and do not have clinical sequelae. No late strokes occurred in this series, and no surgical or interventional treatments were required even in the presence of radiographic worsening. The relatively few cases of vertebral pseudoaneurysms in this series limit any conclusions about these specific lesions. However, these data indicate that follow-up imaging of nonaneurysmal BVI is not necessary in adults who are found to be asymptomatic on follow-up.

Size mismatch in deceased donor liver transplantation and its impact on graft survival.

The impact of size mismatch in deceased donor liver transplantation is unknown. BSA has been demonstrated to be an accurate indicator of liver volume. We developed a model to match livers by BSA and estimate the impact of size mismatch on graft survival. Using the Standard Transplant Analysis and Research (STAR) database we selected solitary primary liver transplants recipients of any age, transplanted between 3/6/2002 and 12/31/2016. Using the Cox proportional hazard model, and controlling for donor and recipient factors, we determined the relative risk for graft survival for four donor/recipient body surface area ratio groups (≤0.68, 0.69-0.90, 0.91-1.25, 1.26-1.5). We studied two groups: recipients with a BSA > 1.6 (adults) and ≤1.6 (children) and a subgroup with a BSA ≤ 0.53 (small infants). In recipients with BSA > 1.6 (adults [n = 71 365]), D/R ratios ≤ 0.68 and > 1.25 had a negative impact on graft survival. In recipients with BSA ≤ 1.6 (children [n = 8339]) D/R ratios <0.75 and >1.25 had a negative impact on graft survival. In the 1725 recipients with BSA ≤ 0.53 (small infants) D/R ratios <1 and >2.3 had a negative impact on graft survival. In deceased donor liver transplantation, the D/R ratio is a significant, yet underestimated predictor of graft survival that should be considered in donor and recipient selection.

Financial benefit of a smoking cessation program prior to elective colorectal surgery.

BACKGROUND: Cigarette smoking increases the risk of postoperative complications nearly 2-fold. Preoperative smoking cessation programs may reduce complications as well as overall postoperative costs. We aim to create an economic evaluation framework to estimate the potential value of preoperative smoking cessation programs for patients undergoing elective colorectal surgery. METHODS: A decision-analytic model from the payer perspective was developed to integrate the costs and incidence of 90-day postoperative complications and readmissions for a cohort of patients undergoing elective colorectal surgery after a smoking cessation program versus usual care. Complication, readmission, and cost data were derived from a cohort of 534 current smokers and recent quitters undergoing elective colorectal resections in Washington State's Surgical Care and Outcomes Assessment Program linked to Washington State's Comprehensive Hospital Abstract Reporting System. Smoking cessation program efficacy was obtained from the literature. Sensitivity analyses were performed to account for uncertainty. RESULTS: For a cohort of patients, the base case estimates imply that the total direct medical costs for patients who underwent a preoperative smoking cessation program were on average $304 (95% CI: $40-$571) lower per patient than those under usual care during the first 90 days after surgery. The model was most sensitive to the odds of recent quitters developing complications or requiring readmission, and smoking program efficacy. CONCLUSIONS: A preoperative smoking cessation program is predicted to be cost-saving over the global postoperative period if the cost of the intervention is below $304 per patient. This framework allows the value of smoking cessation programs of variable cost and effectiveness to be determined.

Expanding access to transplantation with hepatitis C-positive donors: A new perspective on an old issue.

With the need for organs far exceeding supply, donors previously exposed to hepatitis B (HBV) and hepatitis C (HCV) viral infections should be considered for transplantation. Although many centers have protocols for transplanting organs from HBV core antibody-positive (HBcAb+) donors into select recipients, in the era of direct-acting antivirals (DAAs), a new focus should be placed on HCV-positive donors. The transmission rate from HCV antibody-positive (HCVAb+) nucleic acid testing negative (HCV NAT-) donors is expected to be very low, and we encourage use of such organs in HCV recipients provided a normal biopsy, appropriate counseling, and careful post-transplant monitoring. While transmission of HCV from HCV NAT+ donors is universal, the success of DAA in obtaining a sustained viral response in post-transplant recipients should make the use of these organs more appealing. We herein provide information to help guide the use of organs from HCV donors.

Cost-effective targeting of conservation investments to reduce the northern Gulf of Mexico hypoxic zone.

A seasonally occurring summer hypoxic (low oxygen) zone in the northern Gulf of Mexico is the second largest in the world. Reductions in nutrients from agricultural cropland in its watershed are needed to reduce the hypoxic zone size to the national policy goal of 5,000 km(2) (as a 5-y running average) set by the national Gulf of Mexico Task Force's Action Plan. We develop an integrated assessment model linking the water quality effects of cropland conservation investment decisions on the more than 550 agricultural subwatersheds that deliver nutrients into the Gulf with a hypoxic zone model. We use this integrated assessment model to identify the most cost-effective subwatersheds to target for cropland conservation investments. We consider targeting of the location (which subwatersheds to treat) and the extent of conservation investment to undertake (how much cropland within a subwatershed to treat). We use process models to simulate the dynamics of the effects of cropland conservation investments on nutrient delivery to the Gulf and use an evolutionary algorithm to solve the optimization problem. Model results suggest that by targeting cropland conservation investments to the most cost-effective location and extent of coverage, the Action Plan goal of 5,000 km(2) can be achieved at a cost of $2.7 billion annually. A large set of cost-hypoxia tradeoffs is developed, ranging from the baseline to the nontargeted adoption of the most aggressive cropland conservation investments in all subwatersheds (estimated to reduce the hypoxic zone to less than 3,000 km(2) at a cost of $5.6 billion annually).

Evaluating the Correlation Between Anteroposterior Diameter, Body Surface Area, and Height for Liver Transplant Donors and Recipients.

Background: Small stature and female sex correlate to decreased deceased donor liver transplant (DDLT) access and higher waitlist mortality. However, efforts are being made to improve access and equity of allocation under the new continuous distribution (CD) system. Liver anteroposterior diameter (APD) is a method used by many centers to determine size compatibility for DDLT but is not recorded systematically, so it cannot be used for allocation algorithms. We therefore seek to correlate body surface area (BSA) and height to APD in donors and recipients and compare waitlist outcomes by these factors to support their use in the CD system. Methods: APD was measured from single-center DDLT recipients and donors with cross-sectional imaging. Linear, Pearson, and PhiK correlation coefficient were used to correlate BSA and height to APD. Competing risk analysis of waitlist outcomes was performed using United Network for Organ Sharing data. Results: For 143 pairs, donor BSA correlated better with APD than height (PhiK = 0.63 versus 0.20). For recipient all comers, neither BSA nor height were good correlates of APD, except in recipients without ascites, where BSA correlated well (PhiK = 0.63) but height did not. However, among female recipients, BSA, but not height, strongly correlated to APD regardless of ascites status (PhiK = 0.80 without, PhiK = 0.70 with). Among male recipients, BSA correlated to APD only in those without ascites (PhiK = 0.74). In multivariable models, both BSA and height were predictive of waitlist outcomes, with higher values being associated with increased access, decreased delisting for death/clinical deterioration, and decreased living donor transplant (model concordance 0.748 and 0.747, respectively). Conclusions: Taken together, BSA is a good surrogate for APD and can therefore be used in allocation decision making in the upcoming CD era to offset size and gender-based disparities among certain candidate populations.