Ultrasonic debridement management of lower extremity wounds: retrospective analysis of clinical outcomes and cost.

OBJECTIVE: The aim of this study was to assess wound healing outcomes following direct, low-frequency, high-intensity, ultrasonic debridement as a surgical adjunct for non-healing lower extremity wounds. METHODS: A retrospective review was conducted for patients undergoing lower extremity wound treatment with direct, low-frequency (22.5 kHz), high-intensity (~60 W/cm2) ultrasonic debridement between January 2010 and January 2016. Clinical outcomes were assessed up to 180-days post-ultrasonic debridement. Descriptive statistics, cost and univariate analysis were performed. RESULTS: Overall, 82 wounds in 51 patients were included. Mean age was 57.0 years (range: 32-69), and average body mass index (BMI) was 30.8 kg/m². Patient comorbidities consisted of smoking (47%; n=24), hypertension (75%; n=38), diabetes (45%; n=23), and peripheral vascular disease (51%, n=26). Average wound age at initial presentation was 1013 days (range: 2-5475 days) with an average wound size of 9.0cm x 7.4cm. At 180-days post-debridement, 60% (n=49) of wounds had completely healed. Readmission (47%; n=24) and reoperation (45%; n=23) rates were characterised by the reason for readmission and reoperation respectively. Readmission for wound healing (70%, n=39) was primarily for further debridements (41%; n=16). Wound infection (30%; n=7) was the most common readmission for wound complications (30%; n=17). Reoperations primarily consisted of treatments for further wound healing 96% (n=51). Cost analysis showed a lower total treatment cost for patients with improved healing ($78,698), compared with non-improved wounds ($137,707). CONCLUSION: In a complex, heterogeneous cohort of chronic extremity wounds, the use of direct, low-frequency, high-intensity, ultrasonic debridement is a safe and reliable adjunctive therapy for the management of these wounds.

An economical strategy for early medical education in ultrasound.

BACKGROUND: A movement to include ultrasound training in undergraduate medical education is slowly taking place. However, many educational institutions are hesitant to include formal ultrasound training as a part of their curricula due to curricular time constraints, high cost of ultrasound equipment, and a lack of sufficient faculty skilled with ultrasound. We suggest that an economical ultrasound training strategy is needed to resolve these obstacles and enable hesitant medical programs to include ultrasound training. METHODS: Twenty-eight first year medical students volunteered to attend extra-curricular ultrasound training sessions covering topics related to 11 commonly used sonographical imaging categories. Study assessments included subjective pre/post-training skill evaluation surveys, and objective numerical scores awarded by the session instructor during real-time evaluation of each participant's performance in obtaining each target ultrasound view. RESULTS: A Wilcoxon matched-pairs signed rank test was performed to evaluate the difference between pre-training and post-training survey questions. P values < 0.05 were considered significant. Moreover, following analysis the p value for all test was found to be < 0.0001. Of the 308 total ultrasound-related tasks attempted collectively by all 28 participants, only 7 (2.3%) tasks were deemed unsuccessful by an instructor. CONCLUSIONS: The training program presented in this study requires one faculty member, a single ultrasound machine, and time to conduct six 30-min training sessions with small groups of students over 4 weeks. Many medical schools are concerned that they don't have adequate time or resources to include ultrasound training in their curricula. Our intention is to negate these concerns by providing a simple and practical training method that is both temporally and fiscally economical.

High efficiency and low cost preparation of size controlled starch nanoparticles through ultrasonic treatment and precipitation.

The purpose of this work was to develop an approach to produce size controlled starch nanoparticles (SNPs), via precipitation with high efficiency and low cost. High concentration starch aqueous pastes (up to 5wt.%) were treated by ultrasound. Viscosity measurements and size exclusion chromatography characterization revealed that, after 30min ultrasonic treatment, viscosity of the starch pastes decreased two orders of magnitude and the weight average molecular weight of the starch decreased from 8.4×107 to 2.7×106g/mol. Dynamic light scattering measurements and scanning electron microscopy observations showed that the SNPs prepared from the starch pastes with ultrasonic treatments were smaller (∼75nm) and more uniform. Moreover, SNPs could be obtained using less non-solvents. X-ray diffraction results indicated that effect of the ultrasonic treatment on crystalline structure of the SNPs was negligible. Ultrasound can be utilized to prepare smaller SNPs through nanoprecipitation with higher efficiency and lower cost.

Integration of a Low-Cost Introductory Ultrasound Curriculum Into Existing Procedural Skills Education for Preclinical Medical Students.

We evaluated integration of an introductory ultrasound curriculum into our existing mandatory procedural skills program for preclinical medical students. Phantoms consisting of olives, pimento olives, and grapes embedded in opaque gelatin were developed. Four classes encouraged progressive refinement of phantom-scanning and object identification skills. Students improved their ability to identify hidden objects, although each object type achieved a statistically significant improvement in correct identification at different time points. The total phantom cost per student was $0.76. Our results suggest that short repeated experiences scanning simple, low-cost ultrasound phantoms confer basic ultrasound skills.

Comparison of efficacy of laser lithotripter with ultrasonic lithotripter in mini percutaneous nephrolithotomy.

OBJECTIVE: The aim of the study was to compare the efficacy of the laser lithotripter with the ultrasonic lithotripter in mini percutaneous nephrolithotomy (miniperc). MATERIAL AND METHODS: From June 2013 to January 2014; medical records of 77 consecutive patients who underwent miniperc operation were retrospectively evaluated. Ultrasonic lithotripter was used in 22 patients (Group 1), while laser was used in 55 patients. In the laser group, 22 patients were randomly selected who had same characteristics compared to group 1 (Group 2). Success rate, total operative time, complications according to modified Clavien classification, fluoroscopy time, haemoglobin drop, hospital stays and cost analysis were assessed. Success rates were evaluated on the second postoperative day and after the first month. RESULTS: Total operative time (p = 0.635) and fluoroscopy time (p = 0.248) were not significantly different between the two groups. In the laser group, the success rate (81.8%) was notably more than in the ultrasonic lithotripter group (68.2%) but there was no statistically significance (p = 0.296). Ten reusable ultrasonic probe were used for 22 patients, due to thinness and sensitiveness of the probe. Conversely, one single laser fiber (550 micron) was used for 22 patients. When the cost analysis of lithotripsy was considered, the cost per case was 190 dollar in group 1 and 124 dollar in group 2. (p = 0.154) Complication rate, hospital stay and haemoglobin drop were similar in both groups. CONCLUSION: Laser lithotripsy seems to be more cost effective than ultrasonic lithotripsy for miniperc but larger number of patients are required to confirm this estimation.

Alternative Ultrasound Gel for a Sustainable Ultrasound Program: Application of Human Centered Design.

This paper describes design of a low cost, ultrasound gel from local products applying aspects of Human Centered Design methodology. A multidisciplinary team worked with clinicians who use ultrasound where commercial gel is cost prohibitive and scarce. The team followed the format outlined in the Ideo Took Kit. Research began by defining the challenge "how to create locally available alternative ultrasound gel for a low-resourced environment? The "End-Users," were identified as clinicians who use ultrasound in Democratic Republic of the Congo and Ethiopia. An expert group was identified and queried for possible alternatives to commercial gel. Responses included shampoo, oils, water and cornstarch. Cornstarch, while a reasonable solution, was either not available or too expensive. We then sought deeper knowledge of locally sources materials from local experts, market vendors, to develop a similar product. Suggested solutions gleaned from these interviews were collected and used to create ultrasound gel accounting for cost, image quality, manufacturing capability. Initial prototypes used cassava root flour from Great Lakes Region (DRC, Rwanda, Uganda, Tanzania) and West Africa, and bula from Ethiopia. Prototypes were tested in the field and resulting images evaluated by our user group. A final prototype was then selected. Cassava and bula at a 32 part water, 8 part flour and 4 part salt, heated, mixed then cooled was the product design of choice.

A multi-centre randomised trial comparing ultrasound vs mammography for screening breast cancer in high-risk Chinese women.

BACKGROUND: Chinese women tend to have small and dense breasts and ultrasound is a common method for breast cancer screening in China. However, its efficacy and cost comparing with mammography has not been evaluated in randomised trials. METHODS: At 14 breast centres across China during 2008-2010, 13 339 high-risk women aged 30-65 years were randomised to be screened by mammography alone, ultrasound alone, or by both methods at enrollment and 1-year follow-up. RESULTS: A total of 12 519 and 8692 women underwent the initial and second screenings, respectively. Among the 30 cancers (of which 15 were stage 0/I) detected, 5 (0.72/1000) were in the mammography group, 11 (1.51/1000) in the ultrasound group, and 14 (2.02/1000) in the combined group (P=0.12). In the combined group, ultrasound detected all the 14 cancers, whereas mammography detected 8, making ultrasound more sensitive (100 vs 57.1%, P=0.04) with a better diagnostic accuracy (0.999 vs 0.766, P=0.01). There was no difference between mammography and ultrasound in specificity (100 vs 99.9%, P=0.51) and positive predictive value (72.7 vs 70.0%; P=0.87). To detect one cancer, the costs of ultrasound, mammography, and combined modality were $7876, $45 253, and $21 599, respectively. CONCLUSIONS: Ultrasound is superior to mammography for breast cancer screening in high-risk Chinese women.

Applications of sonochemistry in Russian food processing industry.

In food industry, conventional methodologies such as grinding, mixing, and heat treatment are used for food processing and preservation. These processes have been well studied for many centuries and used in the conversion of raw food materials to consumable food products. This report is dedicated to the application of a cost-efficient method of energy transfer caused by acoustic cavitation effects in food processing, overall, having significant impacts on the development of relatively new area of food processing such as food sonochemistry.

Ultrasonic pilot-scale reactor for enzymatic bleaching of cotton fabrics.

The potential of ultrasound-assisted technology has been demonstrated by several laboratory scale studies. However, their successful industrial scaling-up is still a challenge due to the limited pilot and commercial sonochemical reactors. In this work, a pilot reactor for laccase-hydrogen peroxide cotton bleaching assisted by ultrasound was scaled-up. For this purpose, an existing dyeing machine was transformed and adapted by including piezoelectric ultrasonic devices. Laboratory experiments demonstrated that both low frequency, high power (22 kHz, 2100 W) and high frequency, low power ultrasounds (850 kHz, 400 W) were required to achieve satisfactory results. Standard half (4 g/L H2O2 at 90 °C for 60 min) and optical (8 g/L H2O2 at 103 °C for 40 min) cotton bleaching processes were used as references. Two sequential stages were established for cotton bleaching: (1) laccase pretreatment assisted by high frequency ultrasound (850 kHz, 400 W) and (2) bleaching using high power ultrasound (22 kHz, 2100 W). When compared with conventional methods, combined laccase-hydrogen peroxide cotton bleaching with ultrasound energy improved the whitening effectiveness. Subsequently, less energy (temperature) and chemicals (hydrogen peroxide) were needed for cotton bleaching thus resulting in costs reduction. This technology allowed the combination of enzyme and hydrogen peroxide treatment in a continuous process. The developed pilot-scale reactor offers an enhancement of the cotton bleaching process with lower environmental impact as well as a better performance of further finishing operations.

Low-density solvent based ultrasound-assisted emulsification microextraction and on-column derivatization combined with gas chromatography-mass spectrometry for the determination of carbamate pesticides in environmental water samples.

A fast and efficient method for the determination of trace level of carbamate pesticides using a lower-density-than-water solvent for ultrasound-assisted emulsification microextraction coupled to on-column derivatization and analysis by GC-MS has been developed and studied. In this approach, a soft plastic Pasteur pipette was employed as a convenient extraction device. Fifty microliters of extraction solvent, of lower density than water, was injected into the sample solution held in the pipette. The latter was immediately immersed in an ultrasound water bath to form an emulsion. After 2 min extraction, the emulsion was fractionated into two layers by centrifugation. The upper layer (organic extract) could be collected conveniently by squeezing the bulb of the pipette, now held upside down, to move it into the narrow stem of the device, facilitating its retrieval for analysis. The extract was then combined with trimethylphenylammonium hydroxide and directly injected into a gas chromatography-mass spectrometry (GC-MS) system for on-column derivatization and analysis. The on-column derivatization provided an added convenience (since a separate step was not necessary). Parameters affecting the derivatization and extraction were investigated. Under the most favorable conditions, the method demonstrated high extraction efficiency with low limits of detection of between 0.01 and 0.1 µg/L, good linearity in the range of 0.05-50 µg/L, to 0.5-100 µg/L, and good repeatability (RSD below 9.2%, n=5). The proposed method was evaluated by determining carbamate pesticides in river water samples.

Determination of aqueous fullerene aggregates in water by ultrasound-assisted dispersive liquid-liquid microextraction with liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry.

A simple and solvent-minimized method for the determination of three aqueous fullerene aggregates (nC60, nC70, and aqueous [6,6]-phenyl C61 butyric acid methyl ester (nPCBM)) in water samples is described. The method involves the use of ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled liquid chromatography-tandem mass spectrometry with atmospheric pressure photoionization (LC-APPI-MS/MS). The parameters affecting the extraction efficiency of the analytes from water samples were systematically investigated and the conditions optimized. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of 2-propanol (as a disperser solvent) and 10 µL of benzyl bromide (as an extraction solvent) into 10 mL of an aqueous solution (pH 10.0) containing 1% sodium chloride in a conical bottom glass tube. After ultrasonication for 1.0 min and centrifugation at 5000 pm (10 min), the sedimented phase 5.0 µL was directly injected into the LC-APPI-MS/MS system. The limits of quantification (LOQs) were 150, 60 and 8 ng L⁻¹ for nPCBM, nC60 and nC70, respectively. The precision for these analytes, as indicated by relative standard deviations (RSDs), were less than 12% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 70 and 86%. A standard addition method was used to quantitate three aqueous fullerene aggregates, and the concentrations of these aqueous fullerene aggregates were determined to be in the range from n.d. to 130 ng L⁻¹ in various environmental samples including municipal influent and effluent samples, industrial wastewater samples, and surface water samples.