Winoker, Jared S.

Objectives To compare the carbon footprint and environmental impact of single‐use and reusable flexible cystoscopes. Materials and Methods We analysed the expected clinical lifecycle of single‐use (Ambu aScope™ 4 Cysto) and reusable (Olympus CYF‐V2) flexible cystoscopes, from manufacture to disposal. Performance data on cumulative procedures between repairs and before decommissioning were derived from a high‐volume multispecialty practice. We estimated carbon expenditures per‐case using published data on endoscope manufacturing, energy consumption during transportation and reprocessing, and solid waste disposal. Results A fleet of 16 reusable cystoscopes in service for up to 135 months averaged 207 cases between repairs and 3920 cases per lifecycle. Based on a manufacturing carbon footprint of 11.49 kg CO 2 /kg device for reusable flexible endoscopes and 8.54 kg CO 2 /kg device for single‐use endoscopes, the per‐case manufacturing cost was 1.37 kg CO 2 for single‐use devices and 0.0017 kg CO 2 for reusable devices. The solid mass of single‐use and reusable devices was 0.16 and 0.57 kg, respectively. For reusable devices, the energy consumption of reusable device reprocessing using an automated endoscope reprocessor was 0.20 kg CO 2 , and per‐case costs of device repackaging and repair were 0.005 and 0.02 kg CO 2 , respectively. The total estimated per‐case carbon footprint of single‐use and reusable devices was 2.40 and 0.53 kg CO 2 , respectively, favouring reusable devices. Conclusion In this lifecycle analysis, the environmental impact of reusable flexible cystoscopes is markedly less than single‐use cystoscopes. The primary contributor to the per‐case carbon cost of reusable devices is energy consumption of reprocessing.

Introduction: Patients who form kidney stones are typically advised to limit intake of nondairy animal protein. Plant-based meat products may be a processed substitute protein source for these patients and have recently gained popularity because of health concerns, increased retail availability, decreased environmental impact, and meat supply shortages during the COVID-19 pandemic. Despite these perceived benefits and tangential association with whole food plant-based diets, the potential lithogenic risks associated with these products are not well characterized. Methods: The U.S. Department of Agriculture database was queried with a sample of plant-based meat products widely available to U.S. consumers. Nutrient profile data were compiled and compared with animal protein data using standardized serving sizes. Primary protein sources were identified using verified ingredient lists. Oxalate content was extrapolated based on dietary data sources. Results: A total 47 plant-based meat products (16 beef, 11 pork, 10 chicken, and 10 seafood) were analyzed. Compared with their respective animal protein, most products contained on average fewer calories (plant-based beef 77%, pork 94%, chicken 86%, and seafood 83%) and less protein (plant-based beef 68%, pork 96%, chicken 53%, and seafood 54%). Most products used soy protein as the primary protein source (55%). Soy-based beef contained the highest average oxalate content (18 mg per serving), whereas soy-based seafood contained the lowest (7 mg). The most common non-soy protein source was pea protein (30%), containing trace amounts of oxalate. Sodium content was higher in most plant-based products overall (72%) and in each category (plant-based beef 109%, pork 128%, chicken 100%, and seafood 148%). Calcium content was higher (plant-based beef 317%, pork 144%, chicken 291%, and seafood 295%) compared with animal protein. Conclusions: Most plant-based meat products consist of protein sources that are, relative to animal protein sources, higher in oxalate, sodium, and calcium. Stone-forming patients should be counseled about the potential lithogenic risk of these processed products.

Introduction: Multimodal analgesic regimens incorporating peripheral nerve blocks (PNBs) have demonstrated reduced postoperative pain, opioid use, and recovery time in various disease states. However, this remains a subject of limited investigation in the percutaneous nephrolithotomy (PCNL) domain. In the face of an ongoing opioid epidemic and collective push to enhance prescribing stewardship, we sought to examine the potential opioid-sparing effect of PNBs in PCNL. Methods: A systematic review of Embase and PubMed was performed to identify all randomized controlled trials evaluating the use of a PNB with general anesthesia (GA) vs GA alone for pain control following PCNL. Studies evaluating neuraxial (epidural and spinal) anesthesia and those without GA as the control arm were excluded. Results: Seventeen trials evaluating 1,012 procedures were included. Five different blocks were identified and evaluated: paravertebral ( n = 8), intercostal nerve ( n = 3), quadratus lumborum ( n = 2), transversus abdominis plane ( n = 1), and erector spinae ( n = 3). Nine of 16 (56%) studies observed lower pain scores with PNB use throughout the 24-hour postop period. By comparison, improved pain scores with PNBs were limited to the early (<6 hours) recovery period in five studies and two found no difference. Total analgesic and opioid requirements were significantly higher in the GA control arm in nearly all studies (12/14, 86%). Operative times were similar and there were no differences in rates of intercostal access or nephrostomy tube insertion between study arms in any trial. Conclusions: While greater analgesic use with GA alone likely minimizes or obscures differences in patient-reported pain scores, PNBs may offer a significant opioid-sparing analgesic effect during postoperative recovery after PCNL.