Implementation of Low Power and Area Efficient 2-Bit/Step Asynchronous SAR ADC using Successively Activated Comparators

A low power (0.4-09V) 2-Bit/Step successive approximation register (SAR) analog to digital converter (ADC) is conferred. A 2-Bit/Step operation technique is proposed which implementing a dynamic threshold configuring comparator instead of number of digital to analog converters (DACs). Area and power is reduced by successively activated comparators. Here the second comparator is activated reflecting the preceding comparator’s results. Because the second comparator threshold is configured dynamically for every cycle, only two comparators are required instead of three. By successively activating the comparators, the number of DAC settling is halved, so the power and area overhead is very small and the performance will be increased. The proposed ADC was implemented in a 90nm technology achieved a gain of 35.4 db, power of 0.89 ?w and the conversion time of 0.32ns with a supply voltage of 0.4v. The total core area of this ADC is 7.74 ?m2

A Low-Power and High-Speed Frequency Multiplier for DLL-Based Clock Generator

A low-power and high-speed frequency multiplier for a delay-locked loop-based clock generator is proposed to generate a multiplied clock with different range of frequencies. The modified edge combiner consumes low power and achieves a high-speed operation. The proposed frequency multiplier overcomes a deterministic jitter problem by reducing the delay difference between positive- and negative-edge generation paths. The proposed frequency multiplier is implemented in a 0.13-µm CMOS process technology achieved power consumption to a frequency ratio of 2.9 µW/MHz, and has the multiplication ratios of 16, and an output range of 100 MHz–3.3 GHz

Point-Of-Care Ultra-Sound (POCUS) for suspected surgical abdominal conditions in rural India–a mixed-method health needs assessment

Introduction Evidence has shown a trend towards rising mortality from surgical abdominal conditions with increasing distance from hospitals in Eastern India. It has been claimed that imaging modalities such as portable ultrasound are ideal for use in rural areas of developing countries for diagnosis and management of a variety of acute abdominal conditions. This mixed-methods study aimed to explore the need for increased access to POCUS in rural, hard-to-reach populations within India, and to identify barriers that may exist to increasing this access. Methods This mixed-methods study utilized a health needs assessment framework. Quantitative data was extracted from medical records within two outreach camp organisations supporting hard-to-reach populations in Uttarakhand and Jharkhand to provide contextual background statistics. Qualitative data was collected using semi-structured interviews taken from employees of each outreach camp. A framework analysis was employed to analyse the qualitative data. Both datasets were analysed in parallel. Results Twelve semi-structured interviews were undertaken, and 3 months of medical records were reviewed. Themes that presented themselves from the data included the use of camps for case-finding of conditions amenable to routine surgery, a need for POCUS to help with this diagnostic process, a perceived high disease burden from renal calculi, and complex cultural and legislative barriers to POCUS specific to this setting. Discussion POCUS was considered a useful tool in expanding access to surgery for these settings and finding ways of overcoming cultural and legislative barriers to its use should be of high priority. POCUS should be highly portable, robust, easily repairable, and battery operated. For telemedicine to be fully utilised, signal quality will have to be proven to be reliable

Gasless laparoscopy in rural India-registry outcomes and evaluation of the learning curve

Background A program of gasless laparoscopy (GL) has been implemented in rural North-East India. To facilitate safe adoption, participating rural surgeons underwent rigorous training prior to independent clinical practice. An online registry was established to capture clinical data on safety and efficacy and to evaluate initial learning curves for gasless laparoscopy. Methods Surgeons who had completed the GL training program participated in the online RedCap Registry. Patients included in the registry provided informed consent for the use of their data. Data on operative times, conversion rates, perioperative complications, length of stay, and hospital costs were collected. Fixed reference cumulative sum (CUSUM) model was used to evaluate the learning curve based on operative times and conversion rates published in the literature. Results Four surgeons from three rural hospitals in North-East India participated in the registry. The data were collected over 12 months, from September 2019 to August 2020. One hundred and twenty-three participants underwent GL procedures, including 109 females (88.6%) and 14 males. GL procedures included cholecystectomy, appendicectomy, tubal ligation, ovarian cystectomy, diagnostic laparoscopy, and adhesiolysis. The mean operative time was 75.3 (42.05) minutes for all the surgeries. Conversion from GL to open surgery occurred in 11.4% of participants, with 8.9% converted to conventional laparoscopy. The main reasons for conversion were the inability to secure an operative view, lack of operating space, and adhesions. The mean length of stay was 3 (2.1) days. The complication rate was 5.7%, with one postoperative death. The CUSUM analysis for GL cholecystectomy showed a longer learning curve for operative time and few conversions. The learning curve for GL tubal ligation was relatively shorter. Conclusion Gasless laparoscopy can be safely implemented in the rural settings of Northeast India with appropriate training programs. Careful case selection is essential during the early stages of the surgical learning curve

Gasless Laparoscopic Surgery for Minimally Invasive Surgery in Low-Resource Settings: Methods for Evaluating Surgical Field of View and Abdominal Wall Lift Force

Funder: Translate MedTec

Designing devices for global surgery: evaluation of participatory and frugal design methods

Introduction: Most people living in low- and middle-income countries have no access to surgical care. Equipping under-resourced health care contexts with appropriate surgical equipment is thus critical. “Global” technologies must be designed specifically for these contexts. But while models, approaches and methods have been developed for the design of equipment for global surgery, few studies describe their implementation or evaluate their adequacy for this purpose. Methods: A multidisciplinary team applied participatory and frugal design methods to design a surgical device for gasless laparoscopy. The team employed a formal roadmap, devised to guide the development of global surgical equipment, to structure the design process into phases. Phases 0–1 comprised primary research with surgeons working in low-resource settings and forming collaborative partnerships with key stakeholders. These participated in phases 2–3 through design workshops and video events. To conclude, surgical stakeholders (n=13) evaluated a high-fidelity prototype in a cadaveric study. Results: The resulting design, “RAIS” (Retractor for Abdominal Insufflation-less Surgery), received positive feedback from rural surgeons keen to embrace and champion innovation as a result of the close collaboration and participatory design methods employed. The roadmap provided a valuable means to structure the design process but this evaluation highlighted the need for further development to detail specific methodology. The project outcomes were used to develop recommendations for innovators designing global surgical equipment. To inform early phases in the design roadmap, engaging a variety of stakeholders to provide regular input is crucial. Effective communication is vital to elucidate clear functional design requirements and hence reveal opportunities for frugal innovation. Finally, responsible innovation must be embedded within the process of designing devices for global surgery. Conclusion: A community-wide effort is required to formally evaluate and optimize processes for designing global surgical devices and hence accelerate adoption of frugal surgical technologies in low-resource settings

Clinical effectiveness of gasless laparoscopic surgery for abdominal conditions: systematic review and meta-analysis

Background In high-income countries, laparoscopic surgery is the preferred approach for many abdominal conditions. Conventional laparoscopy is a complex intervention that is challenging to adopt and implement in low resource settings. This systematic review and meta-analysis evaluate the clinical effectiveness of gasless laparoscopy compared to conventional laparoscopy with CO2 pneumoperitoneum and open surgery for general surgery and gynaecological procedures. Methods A search of the MEDLINE, EMBASE, Global Health, AJOL databases and Cochrane Library was performed from inception to January 2021. All randomised (RCTs) and comparative cohort (non-RCTs) studies comparing gasless laparoscopy with open surgery or conventional laparoscopy were included. The primary outcomes were mortality, conversion rates and intraoperative complications. Secondary outcomes: operative times and length of stay. The inverse variance random-effects model was used to synthesise data. Results 63 studies were included: 41 RCTs and 22 non-RCTs (3,620 patients). No procedure-related deaths were reported in the studies. For gasless vs conventional laparoscopy there was no difference in intraoperative complications for general RR 1.04 [CI 0.45–2.40] or gynaecological surgery RR 0.66 [0.14–3.13]. In the gasless laparoscopy group, the conversion rates for gynaecological surgery were high RR 11.72 [CI 2.26–60.87] when compared to conventional laparoscopy. For gasless vs open surgery, the operative times were longer for gasless surgery in general surgery RCT group MD (mean difference) 10 [CI 0.64, 19.36], but significantly shorter in the gynaecology RCT group MD − 18.74 [CI − 29.23, − 8.26]. For gasless laparoscopy vs open surgery non-RCT, the length of stay was shorter for gasless laparoscopy in general surgery MD − 3.94 [CI − 5.93, − 1.95] and gynaecology MD − 1.75 [CI − 2.64, − 0.86]. Overall GRADE assessment for RCTs and Non-RCTs was very low. Conclusion Gasless laparoscopy has advantages for selective general and gynaecological procedures and may have a vital role to play in low resource settings

Training programme in gasless laparoscopy for rural surgeons of India (TARGET study) - Observational feasibility study

Background: Benefits of laparoscopic surgery are well recognised but uptake in rural settings of low- and middle-income countries is limited due to implementation barriers. Gasless laparoscopy has been proposed as an alternative but requires a trained rural surgical workforce to upscale. This study evaluates a feasibility of implementing a structured laparoscopic training programme for rural surgeons of North-East India. Methods: A 3-day training programme was held at Kolkata Medical College in March 2019. Laparoscopic knowledge and Fundamentals of Laparoscopic Skills (FLS) were assessed pre and post simulation training using multiple choice questions and the McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS), respectively. Competency with an abdominal lift device was assessed using the Objective Structured Assessment of Technical Skills (OSATS) and live operating performance via the Global Operative Assessment of Laparoscopic Skills (GOALS) scores during live surgery. Costs of the training programme and qualitative feedback were evaluated. Results: Seven rural surgeons participated. There was an improvement in knowledge acquisition (mean difference in MCQ score 5.57 (SD = 4.47)). The overall normalised mean MISTELS score for the FLS tasks improved from 386.02 (SD 110.52) pre-to 524.40 (SD 94.98) post-training (p = 0.09). Mean OSATS score was 22.4 out of 35 (SD 3.31) indicating competency with the abdominal lift device whilst a mean GOALS score of 16.42 out of 25 (SD 2.07) indicates proficiency in performing diagnostic laparoscopy using the gasless technique during live operating. Costs of the course were estimated at 354 USD for trainees and 461 USD for trainers. Conclusion: Structured training programme in gasless laparoscopy improves overall knowledge and skills acquisition in laparoscopic surgery for rural surgeons of North-East India. It is feasible to deliver a training programme in gasless laparoscopy for rural surgeons. Larger studies are needed to assess the benefits for wider adoption in a similar context

What happens next? Review of patients referred for further surgical treatment from rural/mission hospitals

Few decades ago, the mission hospital surgeons felt that if they did not operate the patients had no other place to go, and hence attempted a wide variety of surgeries. Now, with the vast improvement in facilities available in urban areas and the improvement in travel capabilities should the mission hospital surgeons be prepared to do a wide variety of procedures? To answer the above question, we followed up the patients who were referred for surgical procedures elsewhere during the last 12 years. Only 24 out of the 128 patients could afford treatment elsewhere. Twenty of them came back to our hospital and had surgery at a much higher risk because they could not afford the treatment elsewhere. The others chose not to have treatment. Hence, is important then for the few surgeons working in rural areas to a "Jack of all trades" and learn a wide variety of surgical skills if they are to treat the poor patients in rural areas