EP.WE.409Stoma forming surgery – has lockdown changed our operative practice during COVID 19

Aims This study aimed to establish whether the initial lockdown resulted in a shift towards emergency surgery, changes in stoma formation and in rate of surgery with curative intent. Methods A retrospective data collection was performed. Patients were identified using a local database of all patients with stomas. Data was collected from 16/03/20 to 16/09/20. A comparison data set was taken (16/03/19 to 16/09/19). Data was collected on whether the case was performed as an emergency; the type of stoma formed and whether the operation was performed with curative intent. Results Seventeen patients were identified in the 2020 cohort (age: 51-84, mean age: 67.6, M:F 10:7). Fourteen cases (82.4%) were performed as emergencies, three electively (17.6%). Six (35.3%) had end colostomies, three (17.6%) had loop colostomies, one (5.9%) had a caecostomy, four (23.5%) had an end ileostomy and three (17.6%) had a loop ileostomy. Ten operations were for patients with cancer, three (30%) were performed with curative intent. 38 patients were identified in the 2019 cohort (age: 28-85, mean age: 63.0, M:F 17:21). 23 (60.5%) were emergencies, fifteen (39.5%) were performed electively. Nine (23.7%) had end colostomies, eight (21.1%) had loop colostomies, three (7.9%) had caecostomies, ten (26.3%) had end ileostomies and nine (23.7%) had loop ileostomies. There were nineteen operations for cancer, eight (42.1%) were with curative intent. Conclusions Cessation of elective activity caused a shift towards emergency operating, with an associated shift towards surgery with non-curative intent. The distribution of stomas formed has not changed.

1161 Streamlining the Patient Journey for Operative Management During COVID 19

Aim Leeds, UK is a high-volume acute surgery unit. Emergency operating was drastically affected by the pandemic and time from admission to definitive procedure significantly increased. This intervention aimed to streamline the patient journey from acute admission to the operating theatre. Method An audit considering delays to transfer, theatre access and recovery discharge, along with the criteria used for ‘Hot’ theatre was undertaken. Data was collected prospectively between 02/06/2020-06/07/2020 via a standardised proforma. Preliminary results suggested a geographically remote ‘hot’ theatre was associated with multi-factorial delays so was relocated to more familiar surroundings. This was re-audited between 06/07/2020-06/08/2020 aiming to characterise factors contributing to delay. A dedicated in-hours acute theatres porter was introduced for a trial period. Data was collected retrospectively between 24/08/2020-14/09/2020 and prospectively between 14/09-05/10/2020 via hospital electronic systems. Results Initially the average time from patient transfer to leaving theatre recovery was 4h6m55s (N = 52). Relocating theatres reduced this to 2h48m04s (N = 74)- an average reduction of 1h18m51s. The greatest reduction was seen in anaesthetic time between 1h17m54s to 41m29s. The introduction of a dedicated porter reduced the average transfer time to theatre from 36 minutes (N = 53) to 21 minutes (N = 68) (p < 0.05). Conclusions Delay to theatre has a high cost financially and in its effect on patient outcomes. Delays are often multifactorial and robust systems are essential to minimise delays. Patients are best served by well-trained, dedicated ‘Acute’ team in familiar surroundings. Long-term implementation of dedicated portering service will save time, money and improve patient care.

Brachial muscle injury resulting in acute compartment syndrome of the upper arm: a case report and literature review

Background Acute compartment syndrome (ACS) is a potentially devastating condition. ACS is rare in the upper arm. Case presentation We report a case of acute compartment syndrome of the anterior compartment of the upper arm due to brachial muscle injury. The patient experienced abnormal progressive swelling and pain in his right upper arm, and passive pulling pain of the right wrist and right hand. It was highly suspected to be right upper arm compartment syndrome, and was confirmed by surgery. The patient transferred to the emergency operating room for fasciotomy that was performed under general anesthesia using the anterolateral approach. The brachial muscle was found to be heavily swollen and had the greatest tension. The brachial muscle fibers were split lengthwise, and a large amount of hematoma was cleared. The brachial muscles were injured and partly ruptured. After full decompression, a negative pressure drainage device was used to cover the wound in the first stage. Ten days after injury, the swelling of the affected limb subsided and the wound was sutured. The patient’s limbs completely recovered to normal. The shoulder and elbow joints could move freely and the patient resumed normal farming work ability. Conclusion Clinicians should fully recognize the fact that acute compartment syndrome can occur in the upper arm, rather than only the forearm and leg, and therefore avoid serious consequences caused by missed diagnosis and misdiagnosis.

Development of Fuel Product Barrier Monitoring System Based on State Functions in State-Oriented Emergency Operating Procedure

For pressurized water reactor nuclear power plants, in order to prevent the release of radioactive substances into environment, fission product barriers (FPBs) are constructed based on the concept of defense-in-depth, including fuel clad, reactor coolant system (RCS), and containment; the status of these FPBs is then acting as an important dimension to decision-making of emergency action levels (EALs). For CPR1000 nuclear power plants, state functions defined in state-oriented emergency operating procedure (SOP) are used to characterize postaccident physical conditions; their degradation substantially represents the challenges on fundamental safety functions and then on the integrity of FPBs in like manner, so degradation of these state functions is referred to as determining initial conditions of each FPB, by which the link between SOP and EALs is established. Then, an intelligent FPB monitoring system (FPBMS) aiming to automatically monitor states of FPBs is developed, verified, and validated. The pioneering work, by building bridges between state functions and initial conditions of FPBs and then computerizing them innovatively, proves that dynamical monitoring of states of FPBs during accident evolvement and real-time indication of loss or potential loss of FPBs can be achieved, which is most helpful in decision-making of EALs.

Determination of the Electromagnetic Processes Frequency Period in Emergency Operation Modes of Low-Power Multiphase AC Converter-Fed Motors

Increasing requirements for the reliability indicators of technical systems lead to the need to apply new approaches to the design of electric machines and electric drives as an electrical complex, one of which is a systematic approach. To provide a set of increased reliability indicators, it is proposed to use multiphase AC converter-fed motors that differ in structural and algorithmic redundancy It is shown in order to implement variants of AC converter-fed motor circuit, in addition to reliability indicators, a quantitative assessment of its energy capabilities in normal and emergency operating modes is necessary. The most important stage of the practical implementation of the numerical process in the quantitative assessment of energy capabilities is to determine the period of repeatability of electromagnetic processes. The main issues of determining the period of repeatability of quasi-steady-state electromagnetic processes of an electromechanical energy converter of low-power multiphase AC converter-fed motors in the design of systems of increased reliability are considered. This made it possible to implement the numerical solution of systems of differential equations describing the physical processes in AC converter-fed motors with a variable structure of the electromechanical converter in normal and emergency operating modes.

Computer-Aided Analysis of Unbalanced Operating Conditions in Three-Phase Circuits Containing a Dynamic Load

A new approach to analyzing three-phase circuits in the phase coordinates under unbalanced normal and emergency operating conditions is proposed, in which the information about the three-phase circuit to be analyzed by means of software is entered in a simplified manner. The equivalent circuits of three-phase generators, power lines, and static and dynamic loads are aggregated and considered in a generalized form. With such presentation, the work with a three-phase circuit diagram is significantly simplified even if it contains unbalanced loads, a few faulty sections, and control links in the equivalent circuits of electrical machines. The labeling of three-phase circuit nodes is proposed that allows three-phase and single-phase parts of the circuit to be distinguished. The topologic list of branches intended for computer-aided calculations of currents and voltages and currents is compiled for three-phase branches in a generalized form. The obtained list is compact and retains a clear representation of the three-phase circuit. The analogy between the basic electrical equations written for electrical circuit three-phase and single-phase branches is shown. Thus, the voltages and currents in a three-phase element are interrelated by equations similar to the generalized Ohm’s law, while Kirchhoff's current law is written for three-phase nodes and has the same form as for single-phase circuits. The analogy of drawing up the incidence matrix and the matrix of nodal equations is shown. Submatrices of dimensions 3 × 3, 1 × 3, or 1 × 1 depending on the node label appear as entries in the incidence matrices and nodal admittance matrices of a three-phase circuit. The nodal equations used for carrying out the subsequent analysis of the circuit in the phase coordinates are written in a standard way as in single-phase circuits. In analyzing emergency operating conditions, it is proposed to keep the simplicity and clarity of the approach by representing the circuit faulty section of as a corresponding branch embedded into the three-phase circuit. The developed approach is illustrated by calculation of unbalanced and emergency operating conditions in a complex three-phase unbalanced circuit containing two synchronous generators, one dynamic load, and one static load. The calculation has been carried for four- and three-wire three-phase circuits.