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Estuaries are essential habitats for recreational and commercial fish that are shaped by both natural and anthropogenic processes. In Louisiana a combination of climate change and planned coastal restoration actions is predicted to increase freshwater introduction to coastal estuaries. As such there is a need to quantify the relationships between estuarine fish ecology and salinity to aid in predicting how species will respond to shifts in salinity. We investigated the relative abundance and dietary niches of adult (24.5 ± 5.4 cm standard length) spotted seatrout Cynoscion nebulosus across varying salinity regimes (oligohaline, mesohaline, and polyhaline) within Barataria Bay, Louisiana, using a combination of net sampling and gut content and stable isotopes analysis. We found that the relative abundance of C. nebulosus was lowest at the oligohaline site, translating to approximately five fewer fish captured for every single psu decrease in a site's average annual salinity. In contrast, we found that diets and, to a lesser extent, isotopic niches had a high degree of overlap across sites with differing salinity regimes. Fish and penaeid shrimp were the most common and important prey taxa recovered from guts at all sites. The small isotopic differences found among sites were likely due to spatial variation in hydrogeochemical baselines, and the observed isotopic overlap provides support for the idea that C. nebulosus move between adjacent salinity regimes and forage throughout Barataria Bay. Our results contribute to a greater understanding of the salinity preference and trophic ecology of C. nebulosus that can aid in predicting their responses to future salinity and habitat changes within Barataria Bay associated with predicted climate change and planned coastal restoration actions.
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Dieta , Estuarios , Salinidad , Animales , Louisiana , Perciformes/fisiología , Cadena Alimentaria , Contenido Digestivo/química , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisisRESUMEN
Importance: The prevalence of robotic-assisted anterior abdominal wall (ventral) hernia repair has increased dramatically in recent years, despite conflicting evidence of patient benefit. Whether long-term hernia recurrence rates following robotic-assisted repairs are lower than rates following more established laparoscopic or open approaches remains unclear. Objective: To evaluate the association between robotic-assisted, laparoscopic, and open approaches to ventral hernia repair and long-term operative hernia recurrence. Design, Setting, and Participants: Secondary retrospective cohort analysis using Medicare claims data examining adults 18 years and older who underwent elective inpatient ventral, incisional, or umbilical hernia repair from January 1, 2010, to December 31, 2020. Data analysis was performed from January 2023 through March 2024. Exposure: Operative approach to ventral hernia repair, which included robotic-assisted, laparoscopic, and open approaches. Main Outcomes and Measures: The primary outcome was operative hernia recurrence for up to 10 years after initial hernia repair. To help account for potential bias from unmeasured patient factors (eg, hernia size), an instrumental variable analysis was performed using regional variation in the adoption of robotic-assisted hernia repair over time as the instrument. Cox proportional hazards modeling was used to estimate the risk-adjusted cumulative incidence of operative recurrence up to 10 years after the initial procedure, controlling for factors such as patient age, sex, race and ethnicity, comorbidities, and hernia subtype (ventral/incisional or umbilical). Results: A total of 161â¯415 patients were included in the study; mean (SD) patient age was 69 (10.8) years and 67â¯592 patients (41.9%) were male. From 2010 to 2020, the proportion of robotic-assisted procedures increased from 2.1% (415 of 20â¯184) to 21.9% (1737 of 7945), while the proportion of laparoscopic procedures decreased from 23.8% (4799 of 20â¯184) to 11.9% (946 of 7945) and of open procedures decreased from 74.2% (14â¯970 of 20â¯184) to 66.2% (5262 of 7945). Patients undergoing robotic-assisted hernia repair had a higher 10-year risk-adjusted cumulative incidence of operative recurrence (13.43%; 95% CI, 13.36%-13.50%) compared with both laparoscopic (12.33%; 95% CI, 12.30%-12.37%; HR, 0.78; 95% CI, 0.62-0.94) and open (12.74%; 95% CI, 12.71%-12.78%; HR, 0.81; 95% CI, 0.64-0.97) approaches. These trends were directionally consistent regardless of surgeon procedure volume. Conclusions and Relevance: This study found that the rate of long-term operative recurrence was higher for patients undergoing robotic-assisted ventral hernia repair compared with laparoscopic and open approaches. This suggests that narrowing clinical applications and evaluating the specific advantages and disadvantages of each approach may improve patient outcomes following ventral hernia repairs.
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Southern hemisphere humpback whale (Megaptera novaeangliae, SHHW) breeding populations follow a high-fidelity Antarctic krill (Euphausia superba) diet while feeding in distinct sectors of the Southern Ocean. Their capital breeding life history requires predictable ecosystem productivity to fuel migration and migration-related behaviours. It is therefore postulated that populations feeding in areas subject to the strongest climate change impacts are more likely to show the first signs of a departure from a high-fidelity krill diet. We tested this hypothesis by investigating blubber fatty acid profiles and skin stable isotopes obtained from five SHHW populations in 2019, and comparing them to Antarctic krill stable isotopes sampled in three SHHW feeding areas in the Southern Ocean in 2019. Fatty acid profiles and δ13C and δ15N varied significantly among all five populations, however, calculated trophic positions did not (2.7 to 3.1). Similarly, fatty acid ratios, 16:1ω7c/16:0 and 20:5ω3/22:6ω3 were above 1, showing that whales from all five populations are secondary heterotrophs following an omnivorous diet with a diatom-origin. Thus, evidence for a potential departure from a high-fidelity Antarctic krill diet was not seen in any population. δ13C of all populations were similar to δ13C of krill sampled in productive upwelling areas or the marginal sea-ice zone. Consistency in trophic position and diet origin but significant fatty acid and stable isotope differences demonstrate that the observed variability arises at lower trophic levels. Our results indicate that, at present, there is no evidence of a divergence from a high-fidelity krill diet. Nevertheless, the characteristic isotopic signal of whales feeding in productive upwelling areas, or in the marginal sea-ice zone, implies that future cryosphere reductions could impact their feeding ecology.
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Dieta , Euphausiacea , Yubarta , Animales , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Regiones Antárticas , Ácidos Grasos/análisis , Cambio ClimáticoRESUMEN
This Viewpoint discusses developing a more nuanced preoperative optimization strategy for hernia repair that considers patient and disease factors to determine the right operation for the right patient at the right time.
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Herniorrafia , Cuidados Preoperatorios , Humanos , Cuidados Preoperatorios/métodosRESUMEN
BACKGROUND: Documentation of intraoperative details is critical for understanding and advancing hernia care, but is inconsistent in practice. Therefore, to improve data capture on a statewide level, we implemented a financial incentive targeting documentation of hernia defect size and mesh use. METHODS: The Abdominal Hernia Care Pathway (AHCP), a voluntary pay for performance (P4P) initiative, was introduced in 2021 within the statewide Michigan Surgical Quality Collaborative (MSQC). This consisted of an organizational-level financial incentive for achieving 80% performance on eight specific process measures for ventral hernia surgery, including complete documentation of hernia defect size and location, as well as mesh characteristics and fixation technique. Comparisons were made between AHCP and non-AHCP sites in 2021. RESULTS: Of 69 eligible sites, 47 participated in the AHCP in 2021. There were N = 5362 operations (4169 at AHCP sites; 1193 at non-AHCP sites). At AHCP sites, 69.8% of operations had complete hernia documentation, compared to 50.5% at non-AHCP sites (p < 0.0001). At AHCP sites, 91.4% of operations had complete mesh documentation, compared to 86.5% at non-AHCP sites (p < 0.0001). The site-level hernia documentation goal of 80% was reached by 14 of 47 sites (range 14-100%). The mesh documentation goal was reached by 41 of 47 sites (range 4-100%). CONCLUSIONS: Addition of an organizational-level financial incentive produced marked gains in documentation of intra-operative details across a statewide surgical collaborative. The relatively large effect size-19.3% for hernia-is remarkable among P4P initiatives. This result may have been facilitated by surgeons' direct role in documenting hernia size and mesh use. These improvements in data capture will foster understanding of current hernia practices on a large scale and may serve as a model for improvement in collaboratives nationally.
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Hernia Ventral , Humanos , Hernia Ventral/cirugía , Herniorrafia/métodos , Reembolso de Incentivo , Mallas QuirúrgicasRESUMEN
Dams have disrupted natural river systems worldwide and although population and community level effects on aquatic biota have been well documented, food web responses remain poorly understood and difficult to characterize. The application of stable isotope analysis (SIA) provides a means to assess the effect of dams on food webs. Here we review the effect of dams on aquatic food webs using SIA, aiming to detect knowledge gaps in the field of dam impacts on aquatic food webs and propose a conceptual framework to help formulate hypotheses about dam impacts on food webs guided by food web theory. Dams can affect aquatic food webs via two pathways: a bottom-up pathway with altered basal food sources and their transfer to consumers through changes in flow, nutrients, temperature and sediment, and a top-down pathway with consumer species composition altered mainly through habitat fragmentation and related physiochemical changes. Taking these mechanisms into consideration, the impact of dams on food web attributes derived from SIA was evaluated. These studies generally apply mixing models to determine how dams alter the dominant carbon sources supporting food webs, use δ15N to examine how dams alter food-chain length, or use Layman metrics of isotope variability to assess niche changes for invertebrate and fish assemblages. Most studies compare the patterns of SIA metrics spatially (e.g. upstream vs reservoir vs downstream of dams; regulated vs unregulated rivers) and temporally (before vs after dam construction), without explicit hypotheses and/or links to theoretical concepts of food webs. We propose several steps to make SIA studies of dam impacts more rigorous and enhance their potential for producing novel insights. Future studies should quantify the shape and strength of the effect of dams on SIA-measured food web response, be conducted at larger temporal and spatial scales (particularly along the river longitudinal continuum and the lateral connected ecosystems (e.g., floodplains)), and consider effects of dams on food web resilience and tipping points.
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Ecosistema , Cadena Alimentaria , Animales , Invertebrados , Peces , Isótopos de Nitrógeno/análisisRESUMEN
Importance: Roux-en-Y gastric bypass (RYGB) remains one of the most commonly performed operations for morbid obesity and is associated with significant long-term weight loss and comorbidity remission. However, health care utilization rates following RYGB are high and abdominal pain is reported as the most common presenting symptom for those seeking care. Observations: Given the limitations of physical examination in patients with obesity, correct diagnosis of abdominal pain following RYGB depends on a careful history and appropriate use of radiologic, laboratory and endoscopic studies, as well as a clear understanding of post-RYGB anatomy. The most common etiologies of abdominal pain after RYGB are internal hernia, marginal ulcer, biliary disease (eg, cholelithiasis and choledocholithiasis), and jejunojejunal anastomotic issues. Early identification of the etiology of the pain is essential, as some causes, such as internal hernia or perforated gastrojejunal ulcer, may require urgent or emergent intervention to avoid significant morbidity. While laboratory findings and imaging may prove useful, they remain imperfect, and clinical judgment should always be used to determine if surgical exploration is warranted. Conclusions and Relevance: The etiologies of abdominal pain after RYGB range from the relatively benign to potentially life-threatening. This Review highlights the importance of understanding key anatomical and technical aspects of RYGB to guide appropriate workup, diagnosis, and treatment.
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Derivación Gástrica , Hernia Abdominal , Obesidad Mórbida , Humanos , Derivación Gástrica/efectos adversos , Derivación Gástrica/métodos , Obesidad Mórbida/cirugía , Obesidad Mórbida/complicaciones , Dolor Abdominal/diagnóstico , Dolor Abdominal/etiología , Dolor Abdominal/terapia , Medición de Riesgo , Hernia Interna/complicaciones , Estudios RetrospectivosRESUMEN
Despite differences in their overall metabolism, eukaryotes share a common mitochondrial biochemistry. We investigated how this fundamental biochemistry supports overall metabolism using a high-resolution carbon isotope approach, position-specific isotope analysis. We measured carbon isotope 13C/12C cycling in animals, focusing on amino acids that are formed in mitochondrial reactions and are most metabolically active. Carboxyl isotope determinations for amino acids showed strong signals related to common biochemical pathways. Contrasting isotope patterns were measured for metabolism associated with major life history patterns, including growth and reproduction. Turnover of proteins and lipids as well as gluoconeogensis dynamics could be estimated for these metabolic life histories. The high-resolution isotomics measurements fingerprinted metabolism and metabolic strategies across the eukaryotic animal kingdom, yielding results for humans, ungulates, whales, and diverse fish and invertebrates in a nearshore marine food web.
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Aminoácidos , Eucariontes , Animales , Humanos , Eucariontes/metabolismo , Aminoácidos/química , Isótopos de Carbono/análisis , Proteínas , ReproducciónRESUMEN
INTRODUCTION: As survivorship following kidney transplant continues to improve, so does the probability of intervening on common surgical conditions, such as ventral or incisional hernia, in this population. Ventral hernia management is known to vary across institutions and this variation has an impact on patient outcomes. We sought to evaluate hospital level variation of ventral or incisional hernia repair (VIHR) in the kidney transplant population. METHODS: We performed a retrospective review of 100% inpatient Medicare claims to identify patients who underwent kidney transplant between 2007 and 2018. The primary outcome was 1- and 3-year ventral or incisional risk- and reliability-adjusted VIHR rates. Patient and hospital characteristics were evaluated across risk- and reliability-adjusted VIHR rate tertiles. Models were adjusted for age, sex, race, and Elixhauser comorbidities. RESULTS: Overall, 139,741 patients underwent kidney transplant during the study period with a mean age (SD) of 51.6 (13.7) years. 84,717 (60.6%) were male, and 72,657 (52.0%) were white. Median follow up time was 5.4 years. 2098 (1.50%) patients underwent VIHR. the 1 year risk- and reliability-adjusted hernia repair rates were 0.49% (95% Conf idence Interval (CI) 0.48-0.51, range 0.31-0.59) in tertile 1, 0.63% (95% CI 0.62-0.63, range 0.59-0.68) in tertile 2, and 0.98 (95% CI 0.91-1.05, range 0.68-2.94) in tertile 3. Accordingly, compared to hospitals in tertile 1, the odds of post-transplant hernia repair tertile 2 hospitals were 1.78 (95% CI 1.37-2.31) and at tertile 3 hospitals 3.53 (95% CI 2.87-4.33). CONCLUSIONS: In a large cohort of Medicare patients undergoing kidney transplant, the overall cumulative incidence of hernia repair varied substantially across hospital tertiles. Patient and hospital characteristics varied across tertile, most notably in diabetes and obesity. Future research is needed to understand if program and surgeon level factors are contributing to the observed variation in treatment of this common disease.
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Hernia Ventral , Hernia Incisional , Trasplante de Riñón , Humanos , Masculino , Anciano , Estados Unidos/epidemiología , Persona de Mediana Edad , Femenino , Hernia Incisional/epidemiología , Hernia Incisional/etiología , Hernia Incisional/cirugía , Reproducibilidad de los Resultados , Medicare , Hernia Ventral/epidemiología , Hernia Ventral/etiología , Hernia Ventral/cirugía , Estudios Retrospectivos , Herniorrafia , Mallas QuirúrgicasRESUMEN
INTRODUCTION: Preoperative frailty is a strong predictor of postoperative morbidity in the general surgery population. Despite this, there are a paucity of research examining the effect of frailty on outcomes after ventral hernia repair (VHR), one of the most common abdominal operations in the USA. We examined the association of frailty with short-term postoperative outcomes while accounting for differences in preoperative, operative, and hernia characteristics. METHODS: We retrospectively reviewed the Michigan Surgery Quality Collaborative Hernia Registry (MSQC-HR) for adult patients who underwent VHR between January 2020 and January 2022. Patient frailty was assessed using the validated 5-factor modified frailty index (mFI5) and categorized as follows: no (mFI5 = 0), moderate (mFI5 = 1), and severe frailty (mFI5 ≥ 2). Our primary outcome was any 30-day complication. Multivariable logistic regression was used to evaluate the association of frailty with outcomes while controlling for patient, operative, and hernia variables. RESULTS: A total of 4406 patients underwent VHR with a mean age (SD) of 55 (15) years, 2015 (46%) females, and 3591 (82%) white patients. The mean (SD) BMI of the cohort was 33 (8) kg/m2. A total of 2077 (47%) patients had no frailty, 1604 (36%) were moderately frail, and 725 (17%) were severely frail. The median hernia size (interquartile range) was 2.5 cm (1.5-4.0 cm). Severe frailty was associated with increased odds of any complication (adjusted Odds Ratio (aOR) 3.12, 95% CI 1.78-5.47), serious complication (aOR 5.25, 95% CI 2.17-13.19), SSI (aOR 3.41, 95% CI 1.58-7.34), and post-discharge adverse events (aOR 1.70, 95% CI 1.24-2.33). CONCLUSION: After controlling for patient, operative, and hernia characteristics, frailty was independently associated with increased odds of postoperative complications. These findings highlight the importance of preoperative frailty assessment for risk stratification and to inform patient counseling.
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Fragilidad , Hernia Ventral , Adulto , Femenino , Humanos , Persona de Mediana Edad , Masculino , Estudios Retrospectivos , Cuidados Posteriores , Alta del Paciente , Hernia Ventral/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Fragilidad/complicaciones , Factores de RiesgoRESUMEN
INTRODUCTION: Component separation (CS) techniques have evolved in recent years. How surgeons apply the various CS techniques, anterior component separation (aCS) versus posterior component separation (pCS), by patient and hernia-specific factors remain unknown in the general population. Improving the quality of ventral hernia repair (VHR) on a large scale requires an understanding of current practice variations and how these variations ultimately affect patient care. In this study, we examine the application of CS techniques and the associated short-term outcomes while taking into consideration patient and hernia-specific factors. METHODS: We retrospectively reviewed a clinically rich statewide hernia registry, the Michigan Surgical Quality Collaborative Hernia Registry, of persons older than 18 y who underwent VHR between January 2020 and July 2021. The exposure of interest was the use of CS. Our primary outcome was a composite end point of 30-d adverse events including any complication, emergency department visit, readmission, and reoperation. Our secondary outcome was surgical site infection (SSI). Multivariable logistic regression examined the association of CS use, 30-d adverse events, and SSI with patient-, hernia-, and operative-specific variables. We performed a sensitivity analysis evaluating for differences in application and outcomes of the posterior and aCS techniques. RESULTS: A total of 1319 patients underwent VHR, with a median age (interquartile range) of 55 y (22), 641 (49%) female patients, and a median body mass index of 32 (9) kg/m2. CS was used in 138 (11%) patients, of which 101 (73%) were pCS and 37 (27%) were aCS. Compared to patients without CS, patients undergoing a CS had larger median hernia widths (2.5 cm (range 0.01-23 cm) versus 8 cm (1-30 cm), P < 0.001). Of the CS cases, 49 (36%) performed in hernias less than 6 cm in size. Following multivariate regression, factors independently associated with the use of a CS were diabetes (odds ratio [OR]: 2.00, 95% confidence interval [CI]: 1.19-3.36), previous hernia repair (OR: 1.88, 95% CI: 1.20-2.96), hernia width (OR: 1.28, 95% CI: 1.22-1.34), and an open approach (OR: 3.83, 95% CI: 2.24-6.53). Compared to patients not having a CS, use of a CS was associated with increased odds of 30-d adverse events (OR: 1.88 95% CI: 1.13-3.12) but was not associated with SSI (OR: 1.95, 95% CI: 0.74-4.63). Regression analysis demonstrated no differences in 30-d adverse events or SSI between the pCS and aCS techniques. CONCLUSIONS: This is the first population-level report of patients undergoing VHR with concurrent posterior or aCS. These data suggest wide variation in the application of CS in VHR and raises a concern for potential overutilization in smaller hernias. Continued analysis of CS application and the associated outcomes, specifically recurrence, is necessary and underway.
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Hernia Ventral , Humanos , Femenino , Masculino , Hernia Ventral/cirugía , Hernia Ventral/etiología , Herniorrafia/efectos adversos , Herniorrafia/métodos , Músculos Abdominales/cirugía , Estudios Retrospectivos , Infección de la Herida Quirúrgica/etiología , Mallas Quirúrgicas/efectos adversosRESUMEN
BACKGROUND: One approach to evaluate decision-making is using the concept of decision regret, which measures patient remorse after a healthcare decision. This is particularly important for elective, preference-sensitive conditions with multiple treatment options, such as ventral and inguinal hernia repair. In this study, we assessed decision regret among patients who pursued surgical management of ventral and inguinal hernias. METHODS: We retrospectively reviewed a statewide registry of adult patients who underwent elective ventral and inguinal hernia repair between January 2017 and March 2020 and completed a validated survey measuring decision regret. 30-day outcomes included complications, emergency department (ED) utilization, readmission, and reoperation. Multivariable logistic regression examined the association of regret with age, sex, race, insurance status, ASA, tobacco use, diabetes, admission status, surgical approach (open vs. laparoscopic vs. robotic), year, and outcomes. RESULTS: 8315 patients underwent surgery during the study period with a mean age of 60.5 (14.7) years and 1812 (22%) female patients. Among 2159 patients who underwent ventral hernia repair, 248 (11%) reported regret to undergo surgery, 64 (3%) experienced a complication, 160 (7%) visited an ED, 86 (4%) were readmitted, and 29 (1%) underwent reoperation. Outcomes associated with regret after ventral hernia repair included complications (OR 2.33, 95% CI 1.26-4.29) and readmission (OR 2.67, 95% CI 1.51-4.71). Among 6,156 patients who underwent inguinal hernia repair, 533 (9%) reported regret to undergo surgery, 41 (1%) experienced a complication, 304 (5%) visited an ED, 72 (1%) were readmitted, and 63 (1%) underwent reoperation. Outcomes associated with regret after inguinal hernia repair included ED visits (OR 2.03, 95% CI 1.44-2.87) and readmission (OR 4.23, 95% CI 2.35-7.61). CONCLUSION: Roughly 1 in 10 patients undergoing hernia repair report regret with their decision to undergo surgery. Developing a better understanding of the factors associated with decision regret after hernia repair may better inform both patients and surgeon decision-making.
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Hernia Inguinal , Hernia Ventral , Laparoscopía , Adulto , Emociones , Femenino , Hernia Inguinal/complicaciones , Hernia Ventral/complicaciones , Hernia Ventral/epidemiología , Hernia Ventral/cirugía , Herniorrafia/efectos adversos , Humanos , Incidencia , Laparoscopía/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios RetrospectivosRESUMEN
INTRODUCTION: Although the utilization of robotic technique for abdominal hernia repair has increased rapidly, there is no consensus as to when it should be applied for optimal outcomes. High variability exists within surgeon practices regarding how they use this technology, and the factors that drive robotic utilization remain largely unknown. This study aims to explore the motivating factors associated with surgeons' decisions to utilize a robotic approach for abdominal hernia repair. METHODS: An exploratory mixed-methods approach was utilized. Surgeons who performed abdominal hernia repairs were interviewed to identify impactful themes motivating surgical approach. This informed a retrospective analysis of ventral hernia repairs performed in 2020 within the Michigan Surgical Quality Collaborative. Surgeon robotic utilization rates were calculated. Among selective robotic users, multivariable regression evaluated the patient and hernia factors associated with robotic utilization. RESULTS: Qualitative analysis of 21 interviews revealed three dominant themes in the decision to utilize robotic technology: access and resources, surgeon comfort, and market factors. Among 71 surgeons caring for 1174 hernia patients, robotic utilization rates ranged from 0% to 98% of cases. There were 27 surgeons identified as selective robotic users, who cared for 423 patients. Multivariable regression revealed that hernia location was the only factor associated with robotic technique, with non-midline hernias associated with a 4.47 (95% confidence interval 1.34-14.88) higher odds of robotic repair than epigastric hernias. CONCLUSIONS: Major drivers of robotic technique for hernia repair were found to be perceived benefits and availability, rather than patient or hernia characteristics. These data will contribute to an understanding of surgeon decision-making and help develop improvements to patient care.
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Hernia Ventral , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Cirujanos , Hernia Ventral/cirugía , Herniorrafia/efectos adversos , Herniorrafia/métodos , Humanos , Laparoscopía/métodos , Estudios Retrospectivos , Mallas QuirúrgicasRESUMEN
Sediment denitrification plays an important role in nitrogen removal in aquatic systems. However, the importance in nitrogen removal in reservoirs, with a focus on seasonal differences of conditions such as macrophyte beds and environmental factors, is less well understood. This study examined sediment denitrification rate (Dn), and their potential controlling factors were determined in both macrophyte beds and deeper waters in the subtropical reservoir. The mean Dn in the reservoir annually was 18.0 ± 6.3 (mean ± S.E.) mmol N m-2 d-1, with significant seasonal variation (p < 0.01), i.e. 43.2 ± 12.8, 6.7 ± 6.3, and 4.0 ± 2.2 mmol N m-2 d-1 in winter, spring and summer respectively. There were no statistical differences in Dn between shallow waters with macrophyte beds and deeper waters without macrophyte beds, although macrophyte beds had higher denitrification rates in summer. The Dn rates were significantly correlated with temperature, conductivity, dissolved oxygen, pH, nitrate-nitrogen concentration (NO3--N) (p < 0.01) and turbidity (p < 0.05). Linear regression models demonstrated environmental variables explained between 36% and 76% of the variation in Dn. The correlation with NO3--N concentrations suggests that it may be a limited factor for Dn. Annual nitrogen removal of the reservoir by a combination of sediment and water denitrification was totally estimated to be 370 t N with an annual removal efficiency of approximately 11%. Nitrogen removal was much higher in winter than other seasons, with about 305 t N removed, accounting for 12% of the total nitrogen inputs. Therefore, denitrification appears to play a minor role throughout much of the year, but in winter months when nitrate accumulates, it may play a more major role.
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Desnitrificación , Nitratos , Monitoreo del Ambiente , Sedimentos Geológicos , Nitratos/análisis , Nitrógeno/análisisRESUMEN
OBJECTIVE: To evaluate the association between postoperative opioid prescription size and patient-reported satisfaction among surgical patients. SUMMARY BACKGROUND DATA: Opioids are overprescribed after surgery, which negatively impacts patient outcomes. The assumption that larger prescriptions increase patient satisfaction has been suggested as an important driver of excessive prescribing. METHODS: This prospective cohort study evaluated opioid-naive adult patients undergoing laparoscopic cholecystectomy, laparoscopic appendectomy, and minor hernia repair between January 1 and May 31, 2018. The primary outcome was patient satisfaction, collected via a 30-day postoperative survey. Satisfaction was measured on a scale of 0 to 10 and dichotomized into "highly satisfied" (9-10) and "not highly satisfied" (0-8). The explanatory variable of interest was size of opioid prescription at discharge from surgery, converted into milligrams of oral morphine equivalents (OME). Hierarchical logistic regression was performed to evaluate the association between prescription size and satisfaction while adjusting for clinical covariates. RESULTS: One thousand five hundred twenty patients met the inclusion criteria. Mean age was 53 years and 43% of patients were female. One thousand two hundred seventy-nine (84.1%) patients were highly satisfied and 241 (15.9%) were not highly satisfied. After multivariable adjustment, there was no significant association between opioid prescription size and satisfaction (OR 1.00, 95% CI 0.99-1.00). The predicted probability of being highly satisfied ranged from 83% for the smallest prescription (25 mg OME) to 85% for the largest prescription (750 mg OME). CONCLUSIONS: In a large cohort of patients undergoing common surgical procedures, there was no association between opioid prescription size at discharge after surgery and patient satisfaction. This implies that surgeons can provide significantly smaller opioid prescriptions after surgery without negatively affecting patient satisfaction.
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Analgésicos Opioides , Dolor Postoperatorio , Adulto , Humanos , Femenino , Persona de Mediana Edad , Masculino , Analgésicos Opioides/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Satisfacción del Paciente , Estudios Prospectivos , Pautas de la Práctica en Medicina , Morfina , Prescripciones , Estudios RetrospectivosRESUMEN
Trace element accumulation pathways are important in many ecological and toxicological studies on aquatic organisms, yet these pathways are often poorly understood. To study the influence of diet and environment on the trace element composition of species within estuarine food webs, we performed a community level assessment of 28 trace elements (including major and minor elements) in common fish and prawn taxa across four estuaries, and in fish, prawn, and other invertebrate taxa within a single estuary. Despite sediment substrates from the four estuaries having distinctly different geochemical compositions, food web samples showed no separation by estuary, but clear separation by taxa. Grouping of taxa by trace elements was related to feeding ecology, with pelagic taxa separated from benthic taxa, and mixed feeding by generalist taxa. Arsenic and selenium were more concentrated in benthic fish, while aluminium, barium, copper, iron, manganese, vanadium, and zinc were more concentrated in pelagic fish. Trophic level did not appear to influence trace element composition. Previous laboratory studies have shown that food sources influence trace element concentrations in marine taxa and this study confirms that this also occurs in natural food webs. These results improve our understanding of the dominant importance of diet and physiology in controlling the trace element composition of species within estuarine food webs.
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Selenio , Oligoelementos , Animales , Estuarios , Peces , Cadena AlimentariaRESUMEN
RATIONALE: The coupled analysis of δ13 C and δ15 N stable isotope values of blubber and skin biopsy samples is widely used to study the diet of free-ranging cetaceans. Differences in the lipid content of these tissues can affect isotopic variability because lipids are depleted in 13 C, reducing the bulk tissue 13 C/12 C. This variability in carbon isotope values can be accounted for either by chemically extracting lipids from the tissue or by using mathematical lipid normalisation models. METHODS: This study examines (a) the effects of chemical lipid extraction on δ13 C and δ15 N values in blubber and skin of southern hemisphere humpback whales, (b) whether chemical lipid extraction is more favourable than mathematical lipid correction and (c) which of the two tissues is more appropriate for dietary studies. Strategic comparisons were made between chemical lipid extraction and mathematical lipid correction and between blubber and skin tissue δ13 C and δ15 N values, as well as C:N ratios. Six existing mathematical normalisation models were tested for their efficacy in estimating lipid-free δ13 C for skin. RESULTS: Both δ13 C and δ15 N values of lipid-extracted skin (δ13 C: -25.57, δ15 N: 6.83) were significantly higher than those of bulk skin (δ13 C: -26.97, δ15 N: 6.15). Five of the six tested lipid normalisation models had small error terms for predicting lipid-free δ13 C values. The average C:N ratio of lipid-extracted skin was within the lipid-free range reported in other studies, whereas the average C:N ratio of blubber was higher than previously reported. CONCLUSIONS: These results highlight the need to account for lipids when analysing δ13 C and δ15 N values from the same sample. For optimised dietary assessments using parallel isotope analysis from a single sample, we recommend the use of unextracted skin tissue. δ15 N values should be obtained from unextracted skin, whereas δ13 C values may be adequately lipid corrected by a mathematical correction.
Asunto(s)
Tejido Adiposo/química , Yubarta/fisiología , Marcaje Isotópico/métodos , Lípidos , Piel/química , Animales , Isótopos de Carbono/análisis , Lípidos/análisis , Lípidos/aislamiento & purificación , Espectrometría de Masas , Isótopos de Nitrógeno/análisisRESUMEN
BACKGROUND: The "surgical personality" is a mostly negative academic and cultural image of the surgeon as egotistical, paternalistic, and inflexible. Because of this image, surgeons have been viewed as resistant to change and some behaviors, vulnerability, for example, are viewed as "suspect" because they seemingly threaten professional competency. We report on exit interviews of surgeons who participated in a coaching program and demonstrate how their narratives challenge the surgical "personality" and forge an evolving and more open professional surgical identity. METHODS: We interviewed n = 34 bariatric surgeons at the end of a 2-year surgical coaching program. Transcribed interviews were analyzed in NVivo, computer-assisted qualitative data analysis software. Coding of transcripts was approached through iterative steps. We utilized an exploratory method; each member of our team independently examined 3 transcripts to evaluate emergent themes early in the investigation. The team met to discuss our independent themes and develop the codebook collectively. We created a descriptive framework for our first round of coding based on emerging themes and employed an interpretive framework to arrive at our themes. RESULTS: Three major themes emerged from our data. Participants in this study discussed the ways that participation in the coaching program initially conflicted with their identity as a competent professional. Surgeons were acutely aware of how participation might have destabilized their surgical identity because they might be viewed as vulnerable. Despite these concerns about image, surgeons found impetus for improvement because of poor outcome scores or because they desired early career affirmation. Finally, surgeons report that the safe spaces of intentional coaching contributed to their ideas about how surgeons, and ultimately surgery, can change. CONCLUSIONS: Participation in a coaching program challenged how surgeons thought of themselves in relationship to social and peer expectations. Our results indicate that surgeons do feel peer and social pressures related to identity but are much more complex and nuanced than has been previously discussed. The safe space of intentional coaching allowed participants to practice vulnerability without the pressures of sometimes caustic professional norms. Participants in this study viewed coaching as the way to improve the culture of surgery.
Asunto(s)
Cirugía Bariátrica , Educación Médica Continua , Tutoría , Mejoramiento de la Calidad , Identificación Social , Cirujanos/psicología , Humanos , Entrevistas como Asunto , Grabación en VideoRESUMEN
The COVID-19 pandemic has had significant ramifications for provider well-being. During these unprecedented and challenging times, one institution's Department of Surgery put in place several important initiatives for promoting the well-being of trainees as they were redeployed to provide care to COVID-19 patients. In this article, the authors describe these initiatives, which fall into 3 broad categories: redeploying faculty and trainees, ensuring provider safety, and promoting trainee wellness. The redeployment initiatives are the following: reframing the team mindset, creating a culture of grace and forgiveness, establishing a multidisciplinary wellness committee, promoting centralized leadership, providing clear communication, coordinating between departments and programs, implementing phased restructuring of the department's services, establishing scheduling flexibility and redundancy, adhering to training regulations, designating a trainee ombudsperson, assessing physical health risks for high-risk individuals, and planning for structured deimplementation. Initiatives specific to promoting provider safety are appointing a trainee safety advocate, guaranteeing personal protective equipment and relevant information about these materials, providing guidance regarding safe practices at home, and offering alternative housing options when necessary. Finally, the initiatives put in place to directly promote trainee wellness are establishing an environment of psychological safety, providing mental health resources, maintaining the educational missions, solidifying a sense of community by showing appreciation, being attentive to childcare, and using social media to promote community morale. The initiatives to carry out the department's strategy presented in this article, which were well received by both faculty and trainee members of the authors' community, may be employed in other departments and even outside the context of COVID-19. The authors hope that colleagues at other institutions and departments, independent of specialty, will find the initiatives described here helpful during, and perhaps after, the pandemic as they develop their own institution-specific strategies to promote trainee wellness.