Prepacked Take-Home Analgesia in Outpatient Hand Surgery Reduces Opioid Dispensation.

BACKGROUND: Adequate postoperative pain treatment is important for quality of life, patient satisfaction, rehabilitation, function, and total opioid consumption, and might lower both the risk of chronic postoperative pain and the costs for society. Prolonged opioid consumption is a well-known risk factor for addiction. Previous studies in upper extremity surgery have shown that total opioid consumption is a third of the amount prescribed, which can be explained by package size. The aim of this study was to examine whether implementation of prepacked takehome analgesia bags reduced the quantity of prescribed and dispensed opioids. MATERIAL AND METHODS: We introduced prepacked take-home analgesia bags for postoperative pain treatment in outpatient surgery. The bags came in two sizes, each containing paracetamol, etoricoxib, and oxycodone. The first 147 patients who received the prepacked analgesia bags were included in the study, and received a questionnaire one month after surgery covering self-assessed pain (visual analog scale of 0-10) and satisfaction (0-5), as well as opioid consumption. Prescription data after introducing the analgesia bags were compared with data before the bags were introduced. RESULTS: Of the 147 patients included in the study, 58 responded. Compared to standard prescription (small bag group: 14 oxycodone immediate release capsules (5 mg), large bag group: additional 28 oxycodone extended release tablets (5 mg), based on the smallest available package), the patients in the small analgesia bag group received 50% less oxycodone and 67% less for the large bag group. Patients with small bags consumed a median of 0.0 mg oxycodone and those with large bags consumed a median of 25.0 mg oxycodone. The median satisfaction was 5.0 (range: 2-5) and the median pain score was acceptable at the first postoperative day. Prescription data showed a significant reduction of 60.0% in the total amount of prescribed opioids after the introduction of prepacked analgesia bags. CONCLUSIONS: The introduction of prepacked analgesia bags dramatically reduced the quantity of opioids prescribed after outpatient hand surgery. Patient satisfaction was high and the postoperative pain level was acceptable. KEY WORDS: analgesia, hand surgery, opioids, outpatint surgery, wrist surgery.

Nonreciprocal wave phenomena in spring-mass chains with effective stiffness modulation induced by geometric nonlinearity.

Acoustic nonreciprocity has been shown to enable a plethora of effects analogous to phenomena seen in quantum physics and electromagnetics, such as immunity from backscattering and unidirectional band gaps, which could lead to the design of direction-dependent acoustic devices. One way to break reciprocity is by spatiotemporally modulating material properties, which breaks parity and time-reversal symmetries. In this paper, we present a model for a medium in which a slow nonlinear deformation modulates the effective material properties for small overlaid disturbances (often referred to as "small-on-large" propagation). The medium is modeled as a discrete spring-mass chain that undergoes large deformation via prescribed displacements of certain points in the unit cell. A multiple-scale perturbation analysis shows that, for sufficiently slow modulations, the small-scale waves can be described by a linear monatomic chain with time- and space-dependent on-site stiffness. The modulation depth can be tuned by changing the geometric and stiffness parameters of the unit cell. The accuracy of the small-on-large approximation is demonstrated using direct numerical simulations.

Milk mid-infrared spectral data as a tool to predict feed intake in lactating Norwegian Red dairy cows.

Mid-infrared (MIR) spectroscopy of milk was used to predict dry matter intake (DMI) and net energy intake (NEI) in 160 lactating Norwegian Red dairy cows. A total of 857 observations were used in leave-one-out cross-validation and external validation to develop and validate prediction equations using 5 different models. Predictions were performed using (multiple) linear regression, partial least squares (PLS) regression, or best linear unbiased prediction (BLUP) methods. Linear regression was implemented using just milk yield (MY) or fat, protein, and lactose concentration in milk (Mcont) or using MY together with body weight (BW) as predictors of intake. The PLS and BLUP methods were implemented using just the MIR spectral information or using the MIR together with Mcont, MY, BW, or NEI from concentrate (NEIconc). When using BLUP, the MIR spectral wavelengths were always treated as random effects, whereas Mcont, MY, BW, and NEIconc were considered to be fixed effects. Accuracy of prediction (R) was defined as the correlation between the predicted and observed feed intake test-day records. When using the linear regression method, the greatest R of predicting DMI (0.54) and NEI (0.60) in the external validation was achieved when the model included both MY and BW. When using PLS, the greatest R of predicting DMI (0.54) and NEI (0.65) in the external validation data set was achieved when using both BW and MY as predictors in combination with the MIR spectra. When using BLUP, the greatest R of predicting DMI (0.54) in the external validation was when using MY together with the MIR spectra. The greatest R of predicting NEI (0.65) in the external validation using BLUP was achieved when the model included both BW and MY in combination with the MIR spectra or when the model included both NEIconc and MY in combination with MIR spectra. However, although the linear regression coefficients of actual on predicted values for DMI and NEI were not different from unity when using PLS, they were less than unity for some of the models developed using BLUP. This study shows that MIR spectral data can be used to predict NEI as a measure of feed intake in Norwegian Red dairy cattle and that the accuracy is augmented if additional, often available data are also included in the prediction model.

Strategies for implementing genomic selection for feed efficiency in dairy cattle breeding schemes.

Alternative genomic selection and traditional BLUP breeding schemes were compared for the genetic improvement of feed efficiency in simulated Norwegian Red dairy cattle populations. The change in genetic gain over time and achievable selection accuracy were studied for milk yield and residual feed intake, as a measure of feed efficiency. When including feed efficiency in genomic BLUP schemes, it was possible to achieve high selection accuracies for genomic selection, and all genomic BLUP schemes gave better genetic gain for feed efficiency than BLUP using a pedigree relationship matrix. However, introducing a second trait in the breeding goal caused a reduction in the genetic gain for milk yield. When using contracted test herds with genotyped and feed efficiency recorded cows as a reference population, adding an additional 4,000 new heifers per year to the reference population gave accuracies that were comparable to a male reference population that used progeny testing with 250 daughters per sire. When the test herd consisted of 500 or 1,000 cows, lower genetic gain was found than using progeny test records to update the reference population. It was concluded that to improve difficult to record traits, the use of contracted test herds that had additional recording (e.g., measurements required to calculate feed efficiency) is a viable option, possibly through international collaborations.

Discrete breathers in a mass-in-mass chain with Hertzian local resonators.

We report on the existence of discrete breathers in a one-dimensional, mass-in-mass chain with linear intersite coupling and nonlinear, precompressed Hertzian local resonators, which is motivated by recent studies of the dynamics of microspheres adhered to elastic substrates. After predicting theoretically the existence of discrete breathers in the continuum and anticontinuum limits of intersite coupling, we use numerical continuation to compute a family of breathers interpolating between the two regimes in a finite chain, where the displacement profiles of the breathers are localized around one lattice site. We then analyze the frequency-amplitude dependence of the breathers by performing numerical continuation on a linear eigenmode (vanishing amplitude) solution of the system near the upper band gap edge. Finally, we use direct numerical integration of the equations of motion to demonstrate the formation and evolution of the identified localized modes in energy-conserving and dissipative scenarios, including within settings that may be relevant to future experimental studies.

Complex Contact-Based Dynamics of Microsphere Monolayers Revealed by Resonant Attenuation of Surface Acoustic Waves.

Contact-based vibrations play an essential role in the dynamics of granular materials. Significant insights into vibrational granular dynamics have previously been obtained with reduced-dimensional systems containing macroscale particles. We study contact-based vibrations of a two-dimensional monolayer of micron-sized spheres on a solid substrate that forms a microscale granular crystal. Measurements of the resonant attenuation of laser-generated surface acoustic waves reveal three collective vibrational modes that involve displacements and rotations of the microspheres, as well as interparticle and particle-substrate interactions. To identify the modes, we tune the interparticle stiffness, which shifts the frequency of the horizontal-rotational resonances while leaving the vertical resonance unaffected. From the measured contact resonance frequencies we determine both particle-substrate and interparticle contact stiffnesses and find that the former is an order of magnitude larger than the latter. This study paves the way for investigating complex contact-based dynamics of microscale granular crystals and yields a new approach to studying micro- to nanoscale contact mechanics in multiparticle networks.

Standardized CT examination of the multitraumatized patient.

The aim of this study was to develop a standardized non-helical-CT protocol including head, body and proximal extremities in order to achieve a good time efficiency and diagnostic accuracy in the initial radiological evaluation of the multitraumatized patient. A total of 111 circulatory stable blunt trauma patients, brought in to a trauma level II-III hospital, were examined according to a standardized CT protocol. After examining the head with contiguous 10-mm slices without i.v. contrast medium injection, the trunk was examined with 10-mm slices every 30 mm through thorax-abdomen-pelvis with i.v. contrast medium enhancement (occasionally modified). All data in the medical reports were collected and used as "end-point", and the outcome of the CT examination was compared with this final diagnosis. Mean examination time was 20 min (range 12-32 min). In total, 55 head injuries, 89 thoracic injuries, 27 abdominal/pelvic injuries and 62 fractures were found. Computed tomography correctly identified the injuries, except one brain stem injury, one contusion/rupture of the heart, one hepatic injury, two intestinal injuries, eight vertebral injuries and one joint dislocation. A standardized non-helical-CT examination of the head and body may be achieved in 20 min. Its diagnostic accuracy was high, except for vertebral column injuries, which is why we recommend it as the method of choice for initial radiological examination of multitraumatized patients. When available, helical scanning would improve both examination speed and accuracy.

A review of factors affecting biosynthesis of carotenoids by the order Mucorales.

This is a review of factors affecting carotenogenesis by the order Mucorales which includes Phycomyces blakesleeanus, Choanephora cucurbitarum and Blakeslea trispora. The Mucorales have opposite sex types and when mated, beta-carotene production is increased 15 to 20 times. Trisporic acids are the substances produced upon mating which stimulate carotenogenesis. Structural analogs have been shown to mimic the actions of the trisporic acids. The common denominator of the stimulators is the ionone ring and the hydrocarbon side chain. Secondary metabolism is discussed as well as the use of food byproducts to stimulate, specifically, the production of beta-carotene by B. trispora.

Bioinequivalence of erythromycin ethylsuccinate and enteric-coated erythromycin pellets following multiple oral doses.

Bioequivalence comparisons between erythromycin ethylsuccinate and an enteric-coated erythromycin base pellet product were made following multiple-dose, oral administration. Twenty-four volunteers participated in a ten-dose protocol (one dosage unit every six hours) using a complete crossover design. Plasma samples were assayed using a microbiological method specific for erythromycin base in the presence of the ester. Without correcting for the differences in doses administered, the amount of active erythromycin base absorbed from the enteric-coated pellet (250 mg base) was five to seven times that absorbed from the erythromycin ethylsuccinate product (400 mg base equivalent) at steady state. Erythromycin ethylsuccinate is not bioequivalent to an enteric-coated erythromycin base pellet product. The lower bioavailability of the ethylsuccinate may be due to instability in the acidic medium of the stomach.

Relation of age, season, production, and health indices to iodine and beta-carotene concentrations in cow's milk.

Milk samples were collected from 82 Holstein cows during the 1st yr of a 2-yr study and from 44 of these again in the 2nd yr to determine relationships of iodine and beta-carotene concentrations in milk to age, season, placental retention, uterine infections, clinical mastitis, services per conception, and milk yield. Composite milk samples were collected twice weekly at the morning milking. Milk samples from each cow were pooled prior to analyses for the following three times: 1 to 7 wk and 8 to 14 wk postpartum in yr 1 and 1 to 6 wk postpartum in yr 2. Beta-carotene concentrations of milk were inversely related to milk yield and positively related to milk fat percentage. Concentrations tended to be higher for cows experiencing health problems, probably because of lower milk yields and the concommitent higher milk fat content. The relatively low milk iodine concentrations were not generally related to cow age, season of calving, milk yield, milk fat percentage, or to health and performance measures.

Heterogeneity of Samples as a Problem in Shelf-Life Prediction.

A study of the common assumption that a single package of milk represents the production lot was made. Sensory and microbial observations on shelf-life were of sample sets of sequentially produced cartons of milk from four different commercial operations. Neither spoilage rate nor nature of spoilage was uniform for a typical sample set of ten units. A single package, therefore, provided low probability for predicting behavior of the entire production lot. Observations on individual colonies from standard plate counts at the time of sensory spoilage indicated the microflora to be a pure culture in each spoiled unit. The extreme differences in spoilage rates of individual units within sample sets indicated sensory evaluation of multiple samples to be the most logical, simple criterion for evaluating shelf-life. The size of the sample set to be observed and frequency of sampling awaits further observations and application of statistical techniques to establish the accuracy of estimates desired.