Assessment of postoperative nausea and vomiting after bariatric surgery using a validated questionnaire

BACKGROUND: Postoperative nausea and vomiting (PONV) is known to occur after bariatric surgery, with over two thirds of patients affected. However, variability exists in how to objectively measure PONV. OBJECTIVES: The goals of the present study were to use a validated, patient-centered scoring tool, the Rhodes Index of Nausea, Vomiting, and Retching to measure the severity of PONV after bariatric surgery, to directly compare PONV between patients who underwent laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB), and to identify risk factors for the development of PONV after bariatric surgery. SETTING: Barnes-Jewish Hospital/Washington University School of Medicine, St. Louis, Missouri, United States of America. METHODS: The Washington University Weight Loss Surgery team prospectively surveyed patients from January 1, 2017 to December 1, 2018 at the following 6 different timepoints: postoperative day (POD) 0, POD 1, POD 2, POD 3 to 4, the first postoperative outpatient visit (POV 1: POD 5-25), and the second postoperative visit (POV 2: POD 25-50). At each timepoint, a cumulative Rhodes score was calculated from the sum of 8 questions. The American Society for Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database was used to collect patient demographic characteristics and perioperative clinical data. RESULTS: A total of 274 patients met study criteria and completed 605 Rhodes questionnaires. Two hundred fifty Rhodes questionnaires were completed by patients after SG and 355 were completed by patients after LRYGB. Total Rhodes scores are statistically higher in LSG patients compared with patients who underwent LRYGB (LSG = 5.45 ± 6.27; LRYGB = 3.08 ± 4.19, P = .0002). Additionally, at the earlier timepoints, scores were higher among patients who underwent LSG than those who had undergone LRYGB as follows: POD 0 (LSG = 6.96 ± 6.50; LRYGB = 2.89 ± 2.90, P = .0115), POD 1 (LSG = 8.20 ± 6.76; LRYGB = 2.88 ± 3.44, P \u3c .0001), and POD 2 (LSG = 4.05 ± 4.88; LRYGB = 2.06 ± 3.43, P = .05). On subset analysis, examining patients who either underwent an LSG or LRYGB, both procedures had a statistically significant PONV peak emerge on POV 2. Last, overall Rhodes scores were statistically higher in female patients compared with male patients (female: 4.43 ± 5.46; male: 2.35 ± 3.90, P = .021). Although the magnitude of the difference varied somewhat across POD time intervals, the difference was most pronounced at POV 2. CONCLUSIONS: This is the largest study using a validated nausea and vomiting questionnaire to objectively measure PONV after bariatric surgery. The factors found to be most associated with increased PONV were LSG and female sex. Ultimately, these data can help bariatric surgery programs, including Washington University Weight Loss Surgery, identify patients who may require more intensive treatment of PONV, particularly POD 0 to 2, and help to identify patients that continue to struggle with PONV in the later surgical recovery phase

Self-Averaging Scaling Limits of Two-Frequency Wigner Distribution for Random Paraxial Waves

Two-frequency Wigner distribution is introduced to capture the asymptotic behavior of the space-frequency correlation of paraxial waves in the radiative transfer limits. The scaling limits give rises to deterministic transport-like equations. Depending on the ratio of the wavelength to the correlation length the limiting equation is either a Boltzmann-like integral equation or a Fokker-Planck-like differential equation in the phase space. The solutions to these equations have a probabilistic representation which can be simulated by Monte Carlo method. When the medium fluctuates more rapidly in the longitudinal direction, the corresponding Fokker-Planck-like equation can be solved exactly.Comment: typos correcte

A Quantum Langevin Formulation of Risk-Sensitive Optimal Control

In this paper we formulate a risk-sensitive optimal control problem for continuously monitored open quantum systems modelled by quantum Langevin equations. The optimal controller is expressed in terms of a modified conditional state, which we call a risk-sensitive state, that represents measurement knowledge tempered by the control purpose. One of the two components of the optimal controller is dynamic, a filter that computes the risk-sensitive state. The second component is an optimal control feedback function that is found by solving the dynamic programming equation. The optimal controller can be implemented using classical electronics. The ideas are illustrated using an example of feedback control of a two-level atom

Gate complexity using dynamic programming

The relationship between efficient quantum gate synthesis and control theory has been a topic of recent interest in the quantum computing literature. Motivated by this work, we describe how the dynamic programming technique from optimal control may be used in principle to determine gate complexity and for the optimal synthesis of quantum circuits. We illustrate the dynamic programming methodology using a simple example on the Lie group SU(2)

A comparison of 3D particle, fluid and hybrid simulations for negative streamers

In the high field region at the head of a discharge streamer, the electron energy distribution develops a long tail. In negative streamers, these electrons can run away and contribute to energetic processes such as terrestrial gamma-ray and electron flashes. Moreover, electron density fluctuations can accelerate streamer branching. To track energies and locations of single electrons in relevant regions, we have developed a 3D hybrid model that couples a particle model in the region of high fields and low electron densities with a fluid model in the rest of the domain. Here we validate our 3D hybrid model on a 3D (super-)particle model for negative streamers in overvolted gaps, and we show that it almost reaches the computational efficiency of a 3D fluid model. We also show that the extended fluid model approximates the particle and the hybrid model well until stochastic fluctuations become important, while the classical fluid model underestimates velocities and ionization densities. We compare density fluctuations and the onset of branching between the models, and we compare the front velocities with an analytical approximation

Optimal treatment allocations in space and time for on-line control of an emerging infectious disease

A key component in controlling the spread of an epidemic is deciding where, whenand to whom to apply an intervention.We develop a framework for using data to informthese decisionsin realtime.We formalize a treatment allocation strategy as a sequence of functions, oneper treatment period, that map up-to-date information on the spread of an infectious diseaseto a subset of locations where treatment should be allocated. An optimal allocation strategyoptimizes some cumulative outcome, e.g. the number of uninfected locations, the geographicfootprint of the disease or the cost of the epidemic. Estimation of an optimal allocation strategyfor an emerging infectious disease is challenging because spatial proximity induces interferencebetween locations, the number of possible allocations is exponential in the number oflocations, and because disease dynamics and intervention effectiveness are unknown at outbreak.We derive a Bayesian on-line estimator of the optimal allocation strategy that combinessimulation–optimization with Thompson sampling.The estimator proposed performs favourablyin simulation experiments. This work is motivated by and illustrated using data on the spread ofwhite nose syndrome, which is a highly fatal infectious disease devastating bat populations inNorth America

Challenges of Meeting Surgical Needs in the Developing World

The burden of surgical conditions and diseases is increasing in low-income and middle-income countries, but the capacity to meet the demands they present is not following pace. Ongoing initiatives, such as brief visits by surgeons from advantaged countries, sending surgical residents to spend time in a developing country as part of their training, or ships weighing anchor offshore and offering some limited on-shore or on-board services, have not proven successful. More comprehensive and sustainable solutions include the development of local training programs, better retention of trainees with adequate incentives particularly in rural areas, and engaging government and professional associations, as well as academic institutions, to develop and implement policies to address local training needs

"A little theatrical but mostly athletic": The mutable erotics of Miranda July's The First Bad Man

By attending to the inherent flux of sexual fantasy, Miranda July’s first novel The First Bad Man reveals a mobile and mutable erotics capable of generating an enlarged range of self-identification and relational intimacy, far from any essentialist assumptions of stable or coherent sexual identity. July focuses specifically upon role-play as the means to unpack the normative categories of hetero/homosexuality, masculinity and femininity, celebrating rather than pathologising qualities like superficiality and inconsistency. The novel touches upon many polarising issues (for example, sexual violence, sadomasochism and assisted reproductive technology), deftly avoiding the conventional language which colours perception. Both erotic and humorous, The First Bad Man helps to redefine the often highly charged discourse around sex and sexuality

Operative Procedures in the Elderly in Low-Resource Settings: A Review of Médecins Sans Frontières Facilities: Reply

As the demographic transition occurs across developing countries, an increasing number of elderly individuals are affected by disasters and conflicts. This study aimed to evaluate the elderly population that underwent an operative procedure at MSF facilities