Identifying optimal dosing strategies for meropenem in the paediatric intensive care unit through modelling and simulation.

BACKGROUND: Meropenem, a ß-lactam antibiotic commonly prescribed for severe infections, poses dosing challenges in critically ill patients due to highly variable pharmacokinetics. OBJECTIVES: We sought to develop a population pharmacokinetic model of meropenem for critically ill paediatric and young adult patients. PATIENTS AND METHODS: Paediatric intensive care unit patients receiving meropenem 20-40 mg/kg every 8 h as a 30 min infusion were prospectively followed for clinical data collection and scavenged opportunistic plasma sampling. Nonlinear mixed effects modelling was conducted using Monolix®. Monte Carlo simulations were performed to provide dosing recommendations against susceptible pathogens (MIC ≤ 2 mg/L). RESULTS: Data from 48 patients, aged 1 month to 30 years, with 296 samples, were described using a two-compartment model with first-order elimination. Allometric body weight scaling accounted for body size differences. Creatinine clearance and percentage of fluid balance were identified as covariates on clearance and central volume of distribution, respectively. A maturation function for renal clearance was included. Monte Carlo simulations suggested that for a target of 40% fT > MIC, the most effective dosing regimen is 20 mg/kg every 8 h with a 3 h infusion. If higher PD targets are considered, only continuous infusion regimens ensure target attainment against susceptible pathogens, ranging from 60 mg/kg/day to 120 mg/kg/day. CONCLUSIONS: We successfully developed a population pharmacokinetic model of meropenem using real-world data from critically ill paediatric and young adult patients with an opportunistic sampling strategy and provided dosing recommendations based on the patients' renal function and fluid status.

The Impact of Prolonged Operative Time Associated With Minimally Invasive Colorectal Surgery: A Report From the Surgical Care Outcomes Assessment Program.

BACKGROUND: Increased operative time in colorectal surgery is associated with worse surgical outcomes. Laparoscopic and robotic operations have improved outcomes, despite longer operative times. Furthermore, the definition of "prolonged" operative time has not been consistently defined. OBJECTIVE: The first objective was to define prolonged operative time across multiple colorectal operations and surgical approaches. The second was to describe the impact of prolonged operative time on length of stay and short-term outcomes. DESIGN: A retrospective cohort study. SETTING: Forty-two hospitals in the Surgical Care Outcomes Assessment Program from 2011 to 2019. PATIENTS: There were a total of 23,098 adult patients (age 18 years or older) undergoing 6 common, elective colorectal operations: right colectomy, left/sigmoid colectomy, total colectomy, low anterior resection, IPAA, or abdominoperineal resection. MAIN OUTCOME MEASURES: Prolonged operative time defined as the 75th quartile of operative times for each operation and approach. Outcomes were length of stay, discharge home, and complications. Adjusted models were used to account for factors that could impact operative time and outcomes across the strata of open and minimally invasive approaches. RESULTS: Prolonged operative time was associated with longer median length of stay (7 vs 5 days open, 5 vs 4 days laparoscopic, 4 vs 3 days robotic) and more frequent complications (42% vs 28% open, 24% vs 17% laparoscopic, 27% vs 13% robotic) but similar discharge home (86% vs 87% open, 94% vs 94% laparoscopic, 93% vs 96% robotic). After adjustment, each additional hour of operative time above the median for a given operation was associated with 1.08 (1.06-1.09) relative risk of longer length of stay for open operations and 1.07 (1.06-1.09) relative risk for minimally invasive operations. LIMITATIONS: Our study was limited by being retrospective, resulting in selection bias, possible confounders for prolonged operative time, and lack of statistical power for subgroup analyses. CONCLUSIONS: Operative time has consistent overlap across surgical approaches. Prolonged operative time is associated with longer length of stay and higher probability of complications, but this negative effect is diminished with minimally invasive approaches. See Video Abstract . EL IMPACTO DEL TIEMPO OPERATORIO PROLONGADO ASOCIADO CON LA CIRUGA COLORRECTAL MNIMAMENTE INVASIVA UN INFORME DEL PROGRAMA DE EVALUACIN DE RESULTADOS DE ATENCIN QUIRRGICA: ANTECEDENTES:El aumento del tiempo operatorio en la cirugía colorrectal se asocia con peores resultados quirúrgicos. Las operaciones laparoscópicas y robóticas han mejorado los resultados, a pesar de los tiempos operatorios más prolongados. Además, la definición de tiempo operatorio "prolongado" no se ha definido de manera consistente.OBJETIVO:Primero, definir el tiempo operatorio prolongado a través de múltiples operaciones colorrectales y enfoques quirúrgicos. En segundo lugar, describir el impacto del tiempo operatorio prolongado sobre la duración de la estancia y los resultados a corto plazo.DISEÑO:Estudio de cohorte retrospectivo.ESCENARIO:42 hospitales en el Programa de Evaluación de Resultados de Atención Quirúrgica de 2011-2019.PACIENTES:23 098 pacientes adultos (de 18 años de edad y mayores), que se sometieron a seis operaciones colorrectales electivas comunes: colectomía derecha, colectomía izquierda/sigmoidea, colectomía total, resección anterior baja, anastomosis ileoanal con bolsa o resección abdominoperineal.PRINCIPALES MEDIDAS DE RESULTADO:Tiempo operatorio prolongado definido como el cuartil 75 de tiempos operatorios para cada operación y abordaje. Los resultados fueron la duración de la estancia hospitalaria, el alta domiciliaria y las complicaciones. Se usaron modelos ajustados para tener en cuenta los factores que podrían afectar tanto el tiempo operatorio como los resultados en los estratos de abordajes abiertos y mínimamente invasivos.RESULTADOS:El tiempo operatorio prolongado se asoció con una estancia media más prolongada (7 vs. 5 días abiertos, 5 vs. 4 días laparoscópicos, 4 vs. 3 días robóticos), complicaciones más frecuentes (42 % vs. 28 % abiertos, 24 % vs. 17 % laparoscópica, 27% vs. 13% robótica), pero similar alta domiciliaria (86% vs. 87% abierta, 94% vs. 94% laparoscópica, 93% vs. 96% robótica). Después del ajuste, cada hora adicional de tiempo operatorio por encima de la mediana para una operación determinada se asoció con un riesgo relativo de 1,08 (1,06, 1,09) de estancia hospitalaria más larga para operaciones abiertas y un riesgo relativo de 1,07 (1,06, 1,09) para operaciones mínimamente invasivas.LIMITACIONES:Nuestro estudio estuvo limitado por ser retrospectivo, lo que resultó en un sesgo de selección, posibles factores de confusión por un tiempo operatorio prolongado y falta de poder estadístico para los análisis de subgrupos.CONCLUSIONES:El tiempo operatorio tiene una superposición constante entre los enfoques quirúrgicos. El tiempo operatorio prolongado se asocia con una estadía más prolongada y una mayor probabilidad de complicaciones, pero este efecto negativo disminuye con los enfoques mínimamente invasivos. ( Traducción-Dr. Mauricio Santamaria ).

Identification and transcriptomic assessment of latent profile pediatric septic shock phenotypes.

BACKGROUND: Sepsis poses a grave threat, especially among children, but treatments are limited owing to heterogeneity among patients. We sought to test the clinical and biological relevance of pediatric septic shock subclasses identified using reproducible approaches. METHODS: We performed latent profile analyses using clinical, laboratory, and biomarker data from a prospective multi-center pediatric septic shock observational cohort to derive phenotypes and trained a support vector machine model to assign phenotypes in an internal validation set. We established the clinical relevance of phenotypes and tested for their interaction with common sepsis treatments on patient outcomes. We conducted transcriptomic analyses to delineate phenotype-specific biology and inferred underlying cell subpopulations. Finally, we compared whether latent profile phenotypes overlapped with established gene-expression endotypes and compared survival among patients based on an integrated subclassification scheme. RESULTS: Among 1071 pediatric septic shock patients requiring vasoactive support on day 1 included, we identified two phenotypes which we designated as Phenotype 1 (19.5%) and Phenotype 2 (80.5%). Membership in Phenotype 1 was associated with ~ fourfold adjusted odds of complicated course relative to Phenotype 2. Patients belonging to Phenotype 1 were characterized by relatively higher Angiopoietin-2/Tie-2 ratio, Angiopoietin-2, soluble thrombomodulin (sTM), interleukin 8 (IL-8), and intercellular adhesion molecule 1 (ICAM-1) and lower Tie-2 and Angiopoietin-1 concentrations compared to Phenotype 2. We did not identify significant interactions between phenotypes, common treatments, and clinical outcomes. Transcriptomic analysis revealed overexpression of genes implicated in the innate immune response and driven primarily by developing neutrophils among patients designated as Phenotype 1. There was no statistically significant overlap between established gene-expression endotypes, reflective of the host adaptive response, and the newly derived phenotypes, reflective of the host innate response including microvascular endothelial dysfunction. However, an integrated subclassification scheme demonstrated varying survival probabilities when comparing patient endophenotypes. CONCLUSIONS: Our research underscores the reproducibility of latent profile analyses to identify pediatric septic shock phenotypes with high prognostic relevance. Pending validation, an integrated subclassification scheme, reflective of the different facets of the host response, holds promise to inform targeted intervention among those critically ill.

Acute kidney injury is associated with abnormal cefepime exposure among critically ill children and young adults.

BACKGROUND: Elevated cefepime blood concentrations can cause neurotoxicity in adults. The consequences of elevated cefepime concentrations among pediatric patients are unknown. Future exploration of such effects requires first identifying patients at risk for elevated cefepime exposure. We investigated the role of acute kidney injury as a risk factor for increased cefepime concentrations in critically ill children. METHODS: This was a retrospective analysis at a single pediatric intensive care unit. Analyzed patients received at least 24 h of cefepime and had at least two opportunistic samples collected for total cefepime concentration measurement. Individual pharmacokinetic (PK) profiles during treatment courses were reconstructed using Bayesian estimation with an established population PK model. Elevated trough concentration (Cmin) was defined as ≥ 30 mg/L based on adult toxicity studies. The effect of kidney dysfunction on cefepime PK profiles was interrogated using a mixed-effect model. RESULTS: Eighty-seven patients were included, of which 13 (14.9%) had at least one estimated Cmin ≥ 30 mg/L. Patients with elevated Cmin were more likely to have acute kidney injury (AKI) during their critical illness (92% vs. 57%, p = 0.015 for any AKI; 62% vs. 26%, p = 0.019 for severe AKI). Patients who had AKI during critical illness had significantly higher cefepime exposure, as quantified by the area under the concentration-time curve over 24 h (AUC24h) and Cmin. CONCLUSIONS: Among critically ill children, AKI is associated with elevated cefepime concentrations. Identifying these high-risk patients is the first step toward evaluating the clinical consequences of such exposures.

Pharmacokinetic Factors Associated With Early Meropenem Target Attainment in Pediatric Severe Sepsis.

OBJECTIVES: To determine the frequency of early meropenem concentration target attainment (TA) in critically ill children with severe sepsis; to explore clinical, therapeutic, and pharmacokinetic factors associated with TA; and to assess how fluid resuscitation and volume status relate to early TA. DESIGN: Retrospective analysis of prospective observational cohort study. SETTING: PICU in a single academic quaternary care children's hospital. PATIENTS: Twenty-nine patients starting meropenem for severe sepsis (characterized as need for positive pressure ventilation, vasopressors, or ≥ 40 mL/kg bolused fluid), of which 17 were newly escalated to PICU level care. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Concentration-time profiles were analyzed using modeling software employing opportunistic sampling, Bayesian estimation, and a population pharmacokinetic model. Time above four times minimum inhibitory concentration (T > 4×MIC), using the susceptibility breakpoint of 1 µg/mL, was determined for each patient over the first 24 hours of meropenem therapy, as well as individual clearance and volume of distribution (Vd) estimates. Twenty-one of 29 patients met a target of 40%T > MIC 4 µg/mL. Reaching TA, vs. not, was associated with lower meropenem clearance. We failed to identify a difference in Vd or an association between the TA group and age, weight, creatinine-based estimated glomerular filtration rate (eGFR), or the amount of fluid administered. eGFR was, however, negatively correlated with overall T > MIC. CONCLUSIONS: Eight of 29 pediatric patients with early severe sepsis did not meet the selected TA threshold within the first 24 hours of meropenem therapy. Higher clearance was associated with failure to meet targets. Identifying patients likely to have higher meropenem clearance could help with dosing regimens.

Diagnostic Validation of the Updated Pediatric Sepsis Biomarker Risk II for Acute Kidney Injury Prediction Model in Pediatric Septic Shock.

OBJECTIVES: We previously derived the updated Pediatric Sepsis Biomarker Risk for Acute Kidney Injury (PERSEVERE-II AKI) prediction model, which had robust diagnostic test characteristics for severe AKI on day 3 (D3 severe AKI) of septic shock. We now sought to validate this model in an independent cohort of children to the one in which the model was developed. DESIGN: A secondary analysis of a multicenter, prospective, observational study carried out from January 2019 to December 2022. SETTING: Ten PICUs in the United States. PATIENTS: Children with septic shock 1 week to 18 years old admitted to the PICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Seventy-nine of 363 patients (22%) had D3 severe AKI, defined as Kidney Disease Improving Global Outcomes stage 2 or higher. Patients were assigned a probability of D3 severe AKI using the PERSEVERE-II AKI model. The model predicted D3 severe AKI with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.85-0.93), sensitivity of 77% (95% CI, 66-86%), specificity of 88% (95% CI, 84-92%), positive predictive value of 65% (95% CI, 54-74%), and negative predictive value of 93% (95% CI, 89-96%). These data represent an increase in post-test probability of D3 severe AKI with a positive test from 22% to 65%, and a prevalence threshold of 28%. On multivariable regression, the PERSEVERE-II AKI prediction model demonstrated greater adjusted odds ratio (aOR) for D3 severe AKI (aOR, 11.2; 95% CI, 4.9-25.3) and lesser aOR for failure of D3 renal recovery from early AKI (aOR, 0.31; 95% CI, 0.13-0.69). CONCLUSIONS: The PERSEVERE-II AKI model demonstrates consistently robust performance for prediction of new or persistent D3 severe AKI in children with septic shock. A major limitation is that actual D3 severe AKI prevalence is below the prevalence threshold for the test, and thus future work should focus on evaluating use in enriched populations.

Curbing the Obesity Epidemic: Should GLP-1 Receptor Agonists Be the Standard of Care for Obesity?

PURPOSE OF REVIEW: This article summarizes the medical management of obesity with an emphasis on incretin-based therapeutics that target the neuro-hormonal basis of obesity. RECENT FINDINGS: Medications that mimic the effect of incretins, a group of peptide hormones released in response to nutrient intake that regulate appetite, result in potent and durable weight loss. Glucagon-like peptide 1 (GLP-1) agonists and glucose-dependent insulinotropic polypeptide (GIP) agonists such as semaglutide and tirzepatide are approved by the United States Food and Drug Administration (FDA) for the management of obesity. The SELECT trial demonstrated that semaglutide led to a reduction in major adverse cardiovascular events in patients without diabetes who were either overweight and had preexisting cardiovascular disease or obese. SUMMARY: The treatment of obesity is critical to prevent the progression of cardiovascular-kidney-metabolic syndrome. Incretin-based therapies offer remarkable weight loss and reduce major cardiovascular adverse events.

Cefepime pharmacokinetics in critically ill children and young adults undergoing continuous kidney replacement therapy.

OBJECTIVES: Cefepime is an antibiotic commonly used to treat sepsis and is cleared by renal excretion. Cefepime dosing requires adjustment in patients with decreased kidney function and in those receiving continuous kidney replacement therapy (CKRT). We aimed to characterize cefepime PK in a diverse cohort of critically ill paediatric patients on CKRT. METHODS: Patients were identified from an ongoing pharmacokinetic/pharmacodynamic (PK/PD) study of beta-lactam antibiotics, and were included if they had received at least two cefepime doses in the ICU and were on CKRT for at least 24 h. PK parameters were estimated using MwPharm++ with Bayesian estimation and a paediatric population PK model. Target attainment was assessed as time of free cefepime concentrations above minimum inhibitory concentration (fT > 1× or 4 × MIC). RESULTS: Seven patients were included in the study (ages 2 to 20 years). CKRT indications included liver failure (n = 1), renal failure (n = 4) and fluid overload (n = 2). Total effluent flow rates ranged from 1833 to 3115 (mean 2603) mL/1.73 m2/h, while clearance was 2.11-3.70 (mean 3.0) L/h/70 kg. Effluent flows were lower, but clearance and fT > MIC were similar to paediatric data published previously. Using Pseudomonas aeruginosa MIC breakpoints, all patients had 100% of dosing interval above MIC, but only one had 100% of dosing interval above 4× MIC. CONCLUSIONS: Since most patients failed to attain stringent targets of 100% fT > 4×  MIC, model-informed precision dosing may benefit such patients.

Relationship between piperacillin concentrations, clinical factors and piperacillin/tazobactam-associated acute kidney injury.

BACKGROUND: Piperacillin/tazobactam, a commonly used antibiotic, is associated with acute kidney injury (AKI). The relationship between piperacillin concentrations and AKI remains unknown. OBJECTIVE: Estimate piperacillin exposures in critically ill children and young adults administered piperacillin/tazobactam to identify concentrations and clinical factors associated with piperacillin-associated AKI. PATIENTS AND METHODS: We assessed piperacillin pharmacokinetics in 107 patients admitted to the paediatric ICU who received at least one dose of piperacillin/tazobactam. Piperacillin AUC, highest peak (Cmax) and highest trough (Cmin) in the first 24 hours of therapy were estimated. Piperacillin-associated AKI was defined as Kidney Disease: Improving Global Outcomes (KDIGO) Stage 2/3 AKI present >24 hours after initial piperacillin/tazobactam dose. Likelihood of piperacillin-associated AKI was rated using the Naranjo Adverse Drug Reaction Probability Scale. Multivariable logistic regression was performed to identify patient and clinical predictors of piperacillin-associated AKI. RESULTS: Out of 107 patients, 16 (15%) were rated as possibly or probably having piperacillin-associated AKI. Estimated AUC and highest Cmin in the first 24 hours were higher in patients with piperacillin-associated AKI (2042 versus 1445 mg*h/L, P = 0.03; 50.1 versus 10.7 mg/L, P < 0.001). Logistic regression showed predictors of piperacillin-associated AKI included higher Cmin (OR: 5.4, 95% CI: 1.7-23) and age (OR: 1.13, 95% CI: 1.05-1.25). CONCLUSIONS: We show a relationship between estimated piperacillin AUC and highest Cmin in the first 24 hours of piperacillin/tazobactam therapy and piperacillin-associated AKI, suggesting total piperacillin exposure early in the course is associated with AKI development. These data could serve as the foundation for implementation of model-informed precision dosing to reduce AKI incidence in patients given piperacillin/tazobactam.

Ceftriaxone Pharmacokinetics and Pharmacodynamics in 2 Pediatric Patients on Extracorporeal Membrane Oxygenation Therapy.

BACKGROUND: Critically ill patients with cardiac or respiratory failure may require extracorporeal membrane oxygenation (ECMO). Antibiotics are frequently administered when the suspected cause of organ failure is an infection. Ceftriaxone, a ß-lactam antibiotic, is commonly used in patients who are critically ill. Although studies in adults on ECMO have suggested minimal impact on ceftriaxone pharmacokinetics, limited research exists on ceftriaxone pharmacokinetics/pharmacodynamics (PK/PD) in pediatric ECMO patients. We report the PK profiles and target attainment of 2 pediatric patients on ECMO who received ceftriaxone. METHODS: Ceftriaxone concentrations were measured in 2 pediatric patients on ECMO using scavenged opportunistic sampling. PK profiles were generated and individual PK parameters were estimated using measured free ceftriaxone concentrations and a published population PK model in children who are critically ill, using Bayesian estimation. RESULTS: Patient 1, an 11-year-old boy on venovenous ECMO for respiratory failure received 2 doses of 52 mg/kg ceftriaxone 12 hours apart while on ECMO and additional doses every 12 hours off ECMO. On ECMO, ceftriaxone clearance was 13.0 L/h/70 kg compared with 7.6 L/h/70 kg off ECMO, whereas the model-predicted mean clearance in children who are critically ill without ECMO support was 6.54 L/h/70 kg. Patient 2, a 2-year-old boy on venoarterial ECMO due to cardiac arrest received 50 mg/kg ceftriaxone every 12 hours while on ECMO for >7 days. Only clearance while on ECMO could be estimated (9.1 L/h/70 kg). Trough concentrations in both patients were >1 mg/L (the breakpoint for Streptococcus pneumoniae ) while on ECMO. CONCLUSIONS: ECMO increased ceftriaxone clearance above the model-predicted clearances in the 2 pediatric patients studied. Twelve-hour dosing allowed concentrations to remain above the breakpoint for commonly targeted bacteria but not 4 times the breakpoint in one patient, suggesting that precision dosing may be beneficial to ensure target attainment in children on ECMO.

External validation of the modified sepsis renal angina index for prediction of severe acute kidney injury in children with septic shock.

BACKGROUND: Acute kidney injury (AKI) occurs commonly in pediatric septic shock and increases morbidity and mortality. Early identification of high-risk patients can facilitate targeted intervention to improve outcomes. We previously modified the renal angina index (RAI), a validated AKI prediction tool, to improve specificity in this population (sRAI). Here, we prospectively assess sRAI performance in a separate cohort. METHODS: A secondary analysis of a prospective, multicenter, observational study of children with septic shock admitted to the pediatric intensive care unit from 1/2019 to 12/2022. The primary outcome was severe AKI (≥ KDIGO Stage 2) on Day 3 (D3 severe AKI), and we compared predictive performance of the sRAI (calculated on Day 1) to the original RAI and serum creatinine elevation above baseline (D1 SCr > Baseline +). Original renal angina fulfillment (RAI +) was defined as RAI ≥ 8; sepsis renal angina fulfillment (sRAI +) was defined as RAI ≥ 20 or RAI 8 to < 20 with platelets < 150 × 103/µL. RESULTS: Among 363 patients, 79 (22%) developed D3 severe AKI. One hundred forty (39%) were sRAI + , 195 (54%) RAI + , and 253 (70%) D1 SCr > Baseline + . Compared to sRAI-, sRAI + had higher risk of D3 severe AKI (RR 8.9, 95%CI 5-16, p < 0.001), kidney replacement therapy (KRT) (RR 18, 95%CI 6.6-49, p < 0.001), and mortality (RR 2.5, 95%CI 1.2-5.5, p = 0.013). sRAI predicted D3 severe AKI with an AUROC of 0.86 (95%CI 0.82-0.90), with greater specificity (74%) than D1 SCr > Baseline (36%) and RAI + (58%). On multivariable regression, sRAI + retained associations with D3 severe AKI (aOR 4.5, 95%CI 2.0-10.2, p < 0.001) and need for KRT (aOR 5.6, 95%CI 1.5-21.5, p = 0.01). CONCLUSIONS: Prediction of severe AKI in pediatric septic shock is important to improve outcomes, allocate resources, and inform enrollment in clinical trials examining potential disease-modifying therapies. The sRAI affords more accurate and specific prediction than context-free SCr elevation or the original RAI in this population.

A Comparison of US Medicare Expenditures for Hemodialysis and Peritoneal Dialysis.

BACKGROUND: Observations that peritoneal dialysis (PD) may be an effective, lower-cost alternative to hemodialysis for the treatment of ESKD have led to policies encouraging PD and subsequent increases in its use in the United States. METHODS: In a retrospective cohort analysis of Medicare beneficiaries who started dialysis between 2008 and 2015, we ascertained average annual expenditures (for up to 3 years after initiation of dialysis) for patients ≥67 years receiving in-center hemodialysis or PD. We also determined whether differences in Medicare expenditures across dialysis modalities persisted as more patients were placed on PD. We used propensity scores to match 8305 patients initiating PD with 8305 similar patients initiating hemodialysis. RESULTS: Overall average expenditures were US$108,656 (2017) for hemodialysis and US$91,716 for PD (proportionate difference, 1.11; 95% confidence interval [CI], 1.09 to 1.13). This difference did not change over time (P for time interaction term=0.14). Hemodialysis had higher estimated intravenous (iv) dialysis drug costs (1.69; 95% CI, 1.64 to 1.73), rehabilitation expenditures (1.35; 95% CI, 1.26 to 1.45), and other nondialysis expenditures (1.34; 95% CI, 1.30 to 1.37). Over time, initial differences in total dialysis expenditures disappeared and differences in iv dialysis drug utilization narrowed as nondialysis expenditures diverged. Estimated iv drug costs declined by US$2900 per patient-year in hemodialysis between 2008 and 2014 versus US$900 per patient-year in PD. CONCLUSIONS: From the perspective of the Medicare program, savings associated with PD in patients ≥67 years have remained unchanged, despite rapid growth in the use of this dialysis modality. Total dialysis expenditures for the two modalities converged over time, whereas nondialysis expenditures diverged.

Cost Barriers to More Widespread Use of Peritoneal Dialysis in the United States.

The United States Department of Health and Human Services launched the Advancing American Kidney Health Initiative in 2019, which included a goal of transforming dialysis care from an in-center to a largely home-based dialysis program. A substantial motivator for this transition is the potential to reduce costs of ESKD care with peritoneal dialysis. Studies demonstrating that peritoneal dialysis is less costly than in-center hemodialysis have often focused on the perspective of the payer, whereas less consideration has been given to the costs of those who are more directly involved in treatment decision making, including patients, caregivers, physicians, and dialysis facilities. We review comparisons of peritoneal dialysis and in-center hemodialysis costs, focusing on costs incurred by the people and organizations making decisions about dialysis modality, to highlight the financial barriers toward increased adoption of peritoneal dialysis. We specifically address misaligned economic incentives, underappreciated costs for key stakeholders involved in peritoneal dialysis delivery, differences in provider costs, and transition costs. We conclude by offering policy suggestions that include improving data collection to better understand costs in peritoneal dialysis, and sharing potential savings among all stakeholders, to incentivize a transition to peritoneal dialysis.

Population Pharmacokinetic Modeling of Total and Free Ceftriaxone in Critically Ill Children and Young Adults and Monte Carlo Simulations Support Twice Daily Dosing for Target Attainment.

Critical illness, including sepsis, causes significant pathophysiologic changes that alter the pharmacokinetics (PK) of antibiotics. Ceftriaxone is one of the most prescribed antibiotics in patients admitted to the pediatric intensive care unit (PICU). We sought to develop population PK models of both total ceftriaxone and free ceftriaxone in children admitted to a single-center PICU using a scavenged opportunistic sampling approach. We tested if the presence of sepsis and phase of illness (before or after 48 h of antibiotic treatment) altered ceftriaxone PK parameters. We performed Monte Carlo simulations to evaluate whether dosing regimens commonly used in PICUs in the United States (50 mg/kg of body weight every 12 h versus 24 h) resulted in adequate antimicrobial coverage. We found that a two-compartment model best described both total and free ceftriaxone concentrations. For free concentrations, the population clearance value is 6.54 L/h/70 kg, central volume is 25.4 L/70 kg, and peripheral volume is 19.6 L/70 kg. For both models, we found that allometric weight scaling, postmenstrual age, creatinine clearance, and daily highest temperature had significant effects on clearance. The presence of sepsis or phase of illness did not have a significant effect on clearance or volume of distribution. Monte Carlo simulations demonstrated that to achieve free concentrations above 1 µg/ml for 100% of the dosing intervals, a dosing regimen of 50 mg/kg every 12 h is recommended for most patients. A continuous infusion could be considered if the target is to maintain free concentrations four times above the MICs (4 µg/ml).

Evaluating variation in enhanced recovery for colorectal surgery: a report from the Surgical Care Outcomes Assessment Program.

AIM: Robust data demonstrate that enhanced recovery protocols (ERPs) decrease length of stay, complications and cost. However, little is known about the reasons for variation in compliance with ERPs. The aim of this work was to confirm the efficacy of ERPs in a regional network, and to determine factors that are associated with ERP delivery in diverse hospital settings. METHOD: A prospective cohort of patients was created by recording all elective colorectal operations at hospitals in the Surgical Care Outcomes Assessment Program (SCOAP). The delivery of 12 ERP components was tracked at all sites, and factors associated with ERP component delivery and affecting outcomes were reported. RESULTS: From 2016 to 2019, 9274 elective colorectal operations were performed at 36 hospitals. Indications were 48% cancer, 23% diverticulitis and 8% inflammatory bowel disease. Minimally invasive surgery was used in 71%. The proportion of cases with six or more ERP components received increased from 23% in 2016 to 50% in 2019. An increase in components was associated with a shorter length of stay and fewer combined adverse events and reinterventions. Further, increasing numbers of ERP components provided an incremental benefit to patients even when delivered in a low-volume centre or by a low-volume surgeon, and regardless of patient presentation. CONCLUSION: At SCOAP hospitals, the delivery of increasing numbers of ERP components was associated with improved perioperative outcomes and decreased complications after elective colorectal surgery. The variation in delivery of these evidence-based components in subsets of our cohort indicates an important opportunity for quality improvement initiatives.

Inventory of Youth Adaptation to Loss (IYAL): Psychometric Testing of a New Instrument for Bereaved Youth to Assess Social Support and Coping.

The Inventory of Youth Adaptation to Loss (IYAL) was developed to understand the feelings and social supports experienced by bereaved youth to develop an evidence-base for bereavement interventions. The sample included 400 youth ages 9-17, permitting robust psychometric testing of the IYAL. To evaluate the reliability of the IYAL, the sample framework was national in scope, encompassed a range of different types of youth bereavement programs, and purposively sought diversity in the sample. Exploratory factor analysis identified five factors with distinct sub-scales indicating that the IYAL is a valid and reliable assessment instrument of youth coping with grief and their social support relationships.

Obesity protects against sepsis-induced and norepinephrine-induced white adipose tissue browning.

Sepsis is a dysregulated systemic response to infection and can lead to organ damage and death. Obesity is a significant problem worldwide and affects outcomes from sepsis. Our laboratory demonstrated that white adipose tissue (WAT) undergoes browning during sepsis, a process whereby WAT adopts a brown adipose tissue phenotype. However, this browning process was not observed in obese mice during sepsis. White adipose tissue browning is detrimental in patients with burn injury and cancer. We hypothesize that norepinephrine (NE) induces WAT browning in nonobese mice but not in obese mice similarly to sepsis-induced WAT browning. Six-week-old C57BL/6 male mice were randomized to a high-fat diet or normal diet. After 6-7 wk of feeding, polymicrobial sepsis was induced by cecal ligation and puncture (CLP). Norepinephrine was administered intraperitoneally via osmotic minipumps for 18 h or 72 h (no CLP) at which time tissue and plasma were harvested. Controls were mice that underwent CLP (no NE) with 18-h harvest. A separate group of mice underwent pretreatment with NE or vehicle infusion for 72 h, CLP was performed, and at 18 h had tissue and plasma harvested. Sepsis resulted in significant weight loss in both nonobese and obese mice. NE treatment alone caused weight loss in obese mice. Septic nonobese mice had higher uncoupling protein-1 (UCP1) expression compared with control and obese septic mice. NE treatment increased UCP1 expression in nonobese, but not obese mice. NE-treated obese septic mice had lower lung myeloperoxidase (MPO) activity, alanine aminotransferase (ALT), aspartate aminotransferase (AST), TNFα, and IL-6 levels compared with NE-treated nonobese septic mice. Obesity protects mice from septic-induced and NE-induced WAT browning.NEW & NOTEWORTHY White adipose tissue browning is detrimental in patients with burn injury and cancer. WAT browning occurs in nonobese mice and can be induced by ß receptor norepinephrine infusion, but obese mice are resistant to sepsis-induced and norepinephrine-induced WAT browning. We propose that the lack of WAT browning and unchanged inflammatory cytokine response may contribute to the protection of obese mice from sepsis.

Pelvic Floor Nonrelaxation: Approach to Evaluation and Treatment.

Dyssynergic defecation can be a complex, burdensome condition. A multidisciplinary approach to these patients is often indicated based on concomitant pathology or symptomatology across the pelvic organs. Escalating treatment options should be based on shared decision making and include medical and lifestyle optimization, pelvic floor physical therapy with biofeedback, Botox injection, sacral neuromodulation, rectal irrigation, and surgical diversion.

Derivation, Validation, Sustained Performance, and Clinical Impact of an Electronic Medical Record-Based Perioperative Delirium Risk Stratification Tool.

BACKGROUND: Postoperative delirium is an important problem for surgical inpatients and was the target of a multidisciplinary quality improvement project at our institution. We developed and tested a semiautomated delirium risk stratification instrument, Age, WORLD backwards, Orientation, iLlness severity, Surgery-specific risk (AWOL-S), in 3 independent cohorts from our tertiary care hospital and describe its performance characteristics and impact on clinical care. METHODS: The risk stratification instrument was derived with elective surgical patients who were admitted at least overnight and received at least 1 postoperative delirium screen (Nursing Delirium Screening Scale [NuDESC] or Confusion Assessment Method for the Intensive Care Unit [CAM-ICU]) and preoperative cognitive screening tests (orientation to place and ability to spell WORLD backward). Using data pragmatically collected between December 7, 2016, and June 15, 2017, we derived a logistic regression model predicting probability of delirium in the first 7 postoperative hospital days. A priori predictors included age, cognitive screening, illness severity or American Society of Anesthesiologists physical status, and surgical delirium risk. We applied model odds ratios to 2 subsequent cohorts ("validation" and "sustained performance") and assessed performance using area under the receiver operator characteristic curves (AUC-ROC). A post hoc sensitivity analysis assessed performance in emergency and preadmitted patients. Finally, we retrospectively evaluated the use of benzodiazepines and anticholinergic medications in patients who screened at high risk for delirium. RESULTS: The logistic regression model used to derive odds ratios for the risk prediction tool included 2091 patients. Model AUC-ROC was 0.71 (0.67-0.75), compared with 0.65 (0.58-0.72) in the validation (n = 908) and 0.75 (0.71-0.78) in the sustained performance (n = 3168) cohorts. Sensitivity was approximately 75% in the derivation and sustained performance cohorts; specificity was approximately 59%. The AUC-ROC for emergency and preadmitted patients was 0.71 (0.67-0.75; n = 1301). After AWOL-S was implemented clinically, patients at high risk for delirium (n = 3630) had 21% (3%-36%) lower relative risk of receiving an anticholinergic medication perioperatively after controlling for secular trends. CONCLUSIONS: The AWOL-S delirium risk stratification tool has moderate accuracy for delirium prediction in a cohort of elective surgical patients, and performance is largely unchanged in emergent/preadmitted surgical patients. Using AWOL-S risk stratification as a part of a multidisciplinary delirium reduction intervention was associated with significantly lower rates of perioperative anticholinergic but not benzodiazepine, medications in those at high risk for delirium. AWOL-S offers a feasible starting point for electronic medical record-based postoperative delirium risk stratification and may serve as a useful paradigm for other institutions.

Hepatic STAT3 inhibition amplifies the inflammatory response in obese mice during sepsis.

The purpose of this study was to better understand the role obesity plays in the inflammatory response during sepsis, specifically regarding the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway in the liver. We hypothesized that inhibiting STAT3 would lead to an increase in the inflammatory response and that obesity would amplify this effect. To investigate this, we inhibited STAT3 in two ways: pharmacological systemic inhibition and genetic hepatic-specific inhibition. In pharmacological inhibition studies, male C57BL/6 mice were randomized to a high-fat (60% kcal fat) or normal (16% kcal fat) diet for 6-7 wk and pretreated with Stattic before inducing sepsis by cecal ligation and puncture. In genetic inhibition studies, mice were randomized by genotype before induction of sepsis. To investigate obesity in mice with hepatic-specific STAT3 inhibition, we randomized mice to a high-fat or normal diet as described above for 6 mo before induction of sepsis. Body composition was analyzed using EchoMRI. We found that systemic STAT3 inhibition by Stattic resulted in an increased inflammatory response and that obesity amplified this effect. We also found that genetically inhibiting STAT3 in the liver resulted in higher mortality, increased inflammation, and liver injury. High-fat-fed mice with hepatic STAT3 inhibition gained more weight and had more fat than control mice on the same diet, and obesity increased neutrophil infiltration to the liver of these mice during sepsis. In conclusion, STAT3 plays an important regulatory role in the inflammatory response during sepsis, and obesity contributes to the dysregulated response observed when STAT3 is inhibited.