Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society

Authentication of Subjects and Devices Using Biometrics and Identity Management Systems for Persuasive Mobile Computing: A Survey Paper

With the advances in Information Technology (IT) there has been an increase in threats to the communication systems and its assets. One of the most important issues of all IP networks that integrate wireless and wired technologies is the applicability and performance of the electronic identification and authentication methods. These schemes employ a variety of technologies of different degrees of security. Biometrics technology nowadays is typically considered a security necessity, tightly coupled with the foundation of highly secure identification and authentication solutions. This article provides a short survey on different types of authentication and identity management systems. It attempts to describe a summary of related works including some of the latest schemes in face and fingerprint recognition. With a better understanding of electronic authentication techniques any organization can properly select and utilize the technologies which meet its needs

Planning of Personal Area Network (II)

Personal area network (PAN) is a computer network used for communication among computer devices which including telephones and personal digital assistants close to one person. The devices mayor may not belong to the person. Its range is typically a few meters. It is used for intrapersonal communication, connecting higher level network and the internet [I]. Personal area networks can be wired with computer buses such as USB and FireWire. A wireless personal area network (WPAN) can also be made possible with network technologies such as IrDA, Bluetooth, UWB, Z-Wave and ZigBee. The different technologies are explained below

Hardware Evaluation of Near Field Magnetic Induction Communication systems

This paper examines the performance of magnetic induction communication systems for body area networks. First a theoretical study, examination and investigation of the properties and capabilities of near field magnetic induction communications as an emerging form of short range telecommunications access is given. From both a theoretical and hardware tests, results are correlated showing strong agreement between theory and hardware implementation. It is shown that power decay follows an inverse law of distance to power 6 and that certain structures in the communication terrain can affect the magnetic flux created by the transmitter from reaching the receiver thus limiting the range of communications. A body area network of the devices is shown in which a centralised hub aggregates data from the nodes before accessing a wide area network of choic

CLICK-IT: Interactive Television For Sports Action Replay

CLICK-IT (CSIRO Laboratory for Imaging by Content and Knowledge-Interactive Television) is a PC-based system which provides the user with an intelligent highlighter pen for sports action replay. It is intended as a truly interactive improvement on the drawing pad technology currently used for video annotation in sports broadcasting. The system uses computer vision techniques to focus attention and track particular objects, e.g. player(s) or ball, and semiautomatically annotate the dynamic scene. This paper describes the system including the user interface, the tracking technology based on colour and motion information, and system performance evaluation in applications to running rugby league football, basketball and socce

Characteristics Of The Magnetic Bubble 'Cone Of Silence' In Near-Field Magnetic Induction Communications

This paper introduces the concept of bubble factors for assessing the communication bubble created by a near-field magnetic induction (NFMI) communication system. First, the coupling coefficient as a function of distance between two magnetic transmitters is derived and used to show that the induced magnetic field reduces in proportion to the inverse sixth power of distance. This idea is used to define and analyse the communication bubble around the source. Three bubble factors are defined and shown to provide the best approach for quantifying the cone of silence around the transmitter and receiver. The decaying power based on the distance-bubble factor and receiver-load-bubble- factor shows that the transmitted power reduces by 60.25 dB/m. This provides the basis for receiver design and the distance at which interception of the NFMI communication is most secure