Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Compressed higher order modes slot loaded trapezoidal antenna for electromagnetic imaging

A wideband trapezoidal antenna operating at compressed high-order modes is proposed for microwave imaging applications. The antenna is investigated using characteristic mode analysis to show that by loading the slots and using the curved trapezoidal shape, the high-order modes shift to the lower frequency enhance the bandwidth. Multi-square-slotted-ring unit cells are integrated as an artificial magnetic conductor that is located below the antenna to act as a reflector. The proposed antenna operates from 0.85 GHz to 3.7 GHz with an average gain and front to back ratio of 10.5 dBi and 19.5 dB, respectively

Multiband compact low SAR mobile hand held Antenna

With the vast emergence of new mobile applications, multiband operation in a compact size is mandatory for market penetration. In this paper, a new mobile handset antenna suitable for both mobile and wireless LAN services is presented. The antenna operates for most of the mobile applications such as the GSM 900, DCS 1800, PCS 1900, UMTS 2100, and most of the LTE bands, especially the low frequency LTE 700 band at -10 dB. The antenna also supports the WIMAX, WLAN, and the ISM bands. The antenna not only has a compact size, but also supports a low SAR radiation at all the operating frequencies. The antenna consists of two concentric open rings that act as quarter wavelength monopoles. The inner ring radiates at 900MHz, while the outer ring radiates at 700MHz. The inner ring works as a monopole radiator as well as a slot radiator fed by another rectangular monopole. The advantage of the slot is that it supports a wide range of modes that by its role open the radiation band from 1.65 to 3.6GHz. The antenna meets three challenging parameters: compact size, multiband operation including low frequency bands, and low SAR radiation. Good agreement is noticed between the experimental and simulated results

Defected concrete post detection through antenna array coupling effect

In this paper, a proposed defected concrete post detection system is introduced. The proposed system consists of two compact microstrip broad side antenna arrays resonating at 1 GHz with dimensions of 45 cm by 13.2 cm for each antenna array and a weight of 800 gm for both antenna arrays. Also a portable vector network analyser is used for scattering parameters measurement purpose. For size comparison purpose, a conventional microstrip antenna array is designed and compared with the proposed one at the same resonant frequency. A size reduction of 23.4 % is obtained. The proposed antenna array directivity of 10.5 dBi and 3 dB beam width of 30.7 are obtained which are suitable for the concrete post defect detection. The detection principle is relied on the coupling between the two antenna array elements. Three cases are considered for simulation and measurement, air, good concrete block and defected concrete block. A 10 dB difference in coupling was obtained between the presence and the absence of the defect in the concrete block. A proposed measurement system is introduced. Good agreement is obtained between measured and simulated results. The proposed defected concrete post detection system is noticed to be light weight, simple, cheap and has a reasonable accuracy level

Planar UWB MIMO-diversity antenna with dual notch characteristicst

This paper introduces a novel MIMO UWB antenna with dual notches. The proposedantenna is based on Quasi Self Complementary (QSC) method to give wide impedance bandwidthfrom 2.4GHz to more than 12 GHz. The proposed antenna consists of a semi-elliptical patch that isfed by a tapered microstrip line. The antenna is designed on an FR-4 substrate with compact size20mm × 15mm × 1.5mm. The dual notched bands are achieved by using a square ring printed on thebottom of the substrate to reject WiMAX at 3.6 GHz. Also, a C-shaped slot is etched in the radiatingpatch to reject interference with the WLAN band at 5.8 GHz. In the proposed MIMO antenna, theisolation reduction is achieved utilizing diversity technique to minimize the mutual coupling betweenthe antennas. The isolation between MIMO elements is more than 20 dB. The envelope correlationcoefficient (ECC), diversity gain (DG), total active reflection coefficient (TARC), furthermore, channelcapacity loss (CCL) are measured and calculated. The proposed antenna is designed, simulated, andmeasured. A good agreement is shown between the experimental and simulated results

Method of moments analysis for antenna arrays with optimum memory and time consumption

For some applications, single element antennas are unable to meet the gain or radiation pattern requirements.Combining several antenna elements in an array is a possible solution.In order to get accurate analysis of the antenna arrays, full wave analysis techniques such as the method of moments (MoM), the finite difference time domain (FDTD), etc are required.Unfortunately, these methods are heavy computational methods that consume long time and large computational resources.Even with the appearance of the high performance parallel processing resources, the computational time and memory usage still large due to the nature of the problem.So, in this paper, the MoM is chosen to analyze large problems such as antenna arrays taking into consideration the reduction of its needed computational resources and time consuming.The MoM is a well-established and an accurate full wave analysis method.The MoM is applied to solve the electric field integral equation (EFIE) on conducting objects with the use of RWG basis function that is used with triangular segmentation of the scatterer surface.The proposed procedure is to decompose the computational domain into subdomains taking interaction between domains iteratevly until steady state is noticed.The proposed procedure minimizes the time and memory consumption greatly

A multiple‐input‐multiple‐output on‐chip Quasi‐Yagi‐Uda antenna for multigigabit communications: Preliminary study

This article presents a solution for the low gain and the poor efficiency of the on‐chip antennas (OCA). The four elements of Quasi‐Yagi‐Uda antennas (QYUA) are introduced based on the diversity technique to reduce the interference between the elements. In addition, these antennas achieve high isolations between them due to the use of reflector for each antenna. The QYUA is selected to improve the radiation properties of the end‐fire radiator in the millimeter‐wave range for on‐chip systems. The proposed MIMO antenna is used for the point to point communications. The complementary metal‐oxide semiconductor with 180 nm standard is used in the antenna design with six metal layers. The QYUA combines three parts (driven element, reflector, and director); the driven consists of two meander lines fed by coplanar‐slot and operates as a dipole, the reflector is an arc likes a semicircle to prevent the back radiation and increase the front to back ratio, and the director is a meander line to directive the radiation into the proposed direction (front end‐fire direction). All MIMO parameters such as envelope correlation coefficient, channel capacity loss, diversity gain, and total active reflection coefficient in addition to the different configurations of the MIMO are presented. All results are verified by computer simulation technology and high‐frequency structure simulator. The contribution of this article is the MIMO antenna design for point to point communications to serve multigiga communications systems with high data rate and high gain. This MIMO system is considered here to solve the problems of OCA designs