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Introduction We evaluated the incidence of change in serial 12-lead electrocardiogram (ECG) diagnostic classifications in patients resuscitated from out-of-hospital (OH) cardiac arrest (OHCA) comparing OH to emergency department (ED) ECGs. Methods This retrospective case series included: 1) adults (≥ 18 years old), 2) resuscitated from OHCA, 3) ≥ 1 OH and 1 ED ECG/patient, and 4) emergency medical services (EMS) transport to the study hospital. OH and ED ECGs were classified as: 1) STEMI (ST-segment Elevation Myocardial Infarction), 2) Ischemic, and 3) Non-ischemic. Two ED physicians and one cardiologist independently classified all ECGs, then generated a consensus opinion classification for each ECG based on American Heart Association’s 2018 Expert Consensus criteria. The most ischemic OH ECG classification was compared with the last ED ECG classification. Results From 7/27/12 to 7/18/19, 176 patients were entered with a mean age of 61.2 ± 16.6 years; 102/176 (58%) were male. Overall, 504 OH and ED 12-lead ECGs were acquired (2.9 ECGs/patient). ECG classification inter-rater reliability kappa score was 0.63 ± 0.02 (substantial agreement). Overall, 86/176 (49%) changed ECG classification from the OH to ED setting; 69/86 (80%) of these ECGs changed from more to less ischemic classifications. Of 49 OH STEMI ECG classifications, 33/49 (67%) changed to a less ischemic (non-STEMI) ED ECG classification. Conclusions Change in 12-lead ECG classification from OH to ED setting in patients resuscitated from OHCA was common (49%). The OH STEMI classification changed to a less ischemic (non-STEMI) ED classification in 67% of cases.

Background End Tidal CO2 (ETCO2) is a reasonable predictor of Return of Spontaneous Circulation (ROSC) in cardiac arrest (CA), though with many limitations. Cerebral Oximetry (CerOx) non-invasively measures brain O2 saturation and correlates with flow. Objectives This study compares ETCO2 and CerOx for ROSC prediction during both out of hospital (OHCA) and emergency department cardiac arrests (EDCA). Methods We conducted a prospective study on CA patients resuscitated in the ED. ETCO2 and CerOx simultaneously measured during ED CPR. Data was analyzed with logistic regression modeling and area under the curve (AUC). Results 176 patients were analyzed, 66.7% were witnessed, 52.8% had bystander CPR. EMS alert to ED arrival was 27.0 ± 10.6 min. Initial rhythm was 31.8% asystole, 27.8% PEA, 25.6% VF/VT with 26.1% achieving ROSC. AUC predictors of ROSC were: last 5 min trend [CerOx = 0.82 ; ETCO2 = 0.74], delta first to last [CerOx = 0.86 ; ETCO2 = 0.73], the penultimate minute [CerOx = 0.81 ; ETCO2 = 0.76], and final minute [CerOx = 0.89 ; ETCO2 = 0.77]. AUC comparison of simultaneous measurements (n = 125) revealed: last 5 min trend [CerOx = 0.80 ; ETCO2 = 0.79], delta first to last [CerOx = 0.83 ; ETCO2 = 0.75], penultimate minute [CerOx = 0.83 ETCO2 = 0.74], and final minute [CerOx = 0.89 ; ETCO2 = 0.75]. Conclusions Our data shows, both ETCO2 and rSO2 are good predictors of ROSC. We found CerOx superior to ETCO2 in predicting ROSC.

End Tidal COThis study compares ETCOWe conducted a prospective study on CA patients resuscitated in the ED. ETCO176 patients were analyzed, 66.7% were witnessed, 52.8% had bystander CPR. EMS alert to ED arrival was 27.0 ± 10.6 min. Initial rhythm was 31.8% asystole, 27.8% PEA, 25.6% VF/VT with 26.1% achieving ROSC. AUC predictors of ROSC were: last 5 min trend [CerOx = 0.82 ; ETCOOur data shows, both ETCO2 and rSO2 are good predictors of ROSC. We found CerOx superior to ETCO

Abstract Well integrity has become an increasingly important issue for oilfield components. Stricter testing procedures and qualification requirements are becoming more prevalent for primary well fluid containment devices. This is being extended to well monitoring systems, including those permanently installed on well completions using electronic or optical cables. One example is the new fire test requirement for Optical Well Head Outlets (OWHO) per Statoil's document TR3540, Surface wellhead and christmas tree system, with procedures defined in API 6FB: Fire Test for End Connections. Operators are also demanding increased reliability for downhole systems. Ensuring that the seals are properly installed and functional in drymate connectors and pressure foot devices is critical. This paper discusses the development and qualification of an OWHO that meets API 6FB. Key design issues such as thermal coefficient of expansion differences of materials, seal evaluations, and feed-through issues as related to surviving the extreme temperature conditions of the flame test are discussed. Development and testing of pressure-testable multipin drymate connectors and an improved pressure foot design is also discussed. Development of highly reliable downhole components requires significant design and testing. For the OWHO, an internal pressure of 11, 250 psi (775.7 bar) was maintained while the wellhead outlet was brought to a temperature that exceeded 900°C (1, 652°F), with the internal feed-through exceeding 650°C (1, 202°F) during the test. The OWHO experienced no leaks at any stage of the qualification testing. The design of the pressure-testable drymate connector and pressure foot has been developed to qualify for infield hydraulic tests. The OWHO met the harsh environment requirements of TR3540 through a successful flame test carried out in accordance with API 6FB. The newly designed drymate connector and pressure foot provide a reliable, field-testable solution representing a significant step forward to ensuring well integrity.

Deburring is a critical step in the manufacture of a machined part. The two-pass control concept of this paper removes burrs and produces a consistent chamfer, even with fixture, part, and robot errors. The approach requires a robot for gross positioning of the cutter and an around-the-arm end effector capable of measuring orthogonal force between cutter and workpiece, measuring cutter position with respect to end- effector frame of reference, and actively controlling the cutter-applied orthogonal force. In the first pass, compliance control (orthogonal to workpiece) removes burrs by programming the cutter to act as a low-pass filter on the burrs, where the cutter bandwidth is less than burr time-frequency content, while complying to the fixture, part, and robot errors. In the second pass, chamfer depth variations are smoothed out using chamfer control, where chamfer depth is controlled by computing an estimated real-time chamfer depth, and using this estimate in a feedback loop that varies the cutter-workpiece force to maintain a commanded chamfer depth. The chamfer depth estimator removes repeatable fixture, part, and robot errors by using cutter position measurements from the first pass. Cutting experiments on edges with burrs show that compliance control improved on the force control approach in compensating for burrs, and chamfer control was able to produce a consistent chamfer depth.

Wet steam is a common occurrence at the exhaust of the LP turbines in fossil-fired steam plants. In nuclear turbines, wet steam will be found right from the high-pressure sections. The presence of moisture in steam reduces the aerodynamic efficiency of the turbine sections, thus reducing the overall efficiency of the turbine. Additionally, water droplets also cause erosion and corrosion of buckets and other components. LP turbines account for a significant portion of the total cost of the turbines (due to the enormous sizes required by the expanding steam) and produce significant portion of the power output. Measuring and controlling wetness will help improve both the performance and reliability of turbines. A novel way of measuring the composition of wet steam using a speed of sound based technique is being developed. The technique, based on technology developed for measuring two-phase flow compositions in down-hole (oil-field) applications, relies on measuring acoustic pressures propagating in a one-dimensional wave-guide (pipe or tube) using an array of axially located pressure transducers. The technique is non-intrusive to the flow field and relies on passive listening of the noise generated by the flow itself (and, hence differs from the conventional ultrasound based techniques). The current study is an ongoing effort and the paper will focus on the feasibility of this technique for wet steam application. The eventual aim is to be able to measure steam wetness in the range of 0–10% with an accuracy of ± 0.2%. Initially, the ability of the technique to accurately measure the wetness in air-water mixture was established using an air and water mist facility. Next, high subsonic flow conditions were evaluated in single phase (air only) flow using a wind tunnel facility. Excellent agreement between speed of sound calculated for air, based on conventional pressure and temperature measurements in a wind tunnel, and that measured directly by the probe was obtained. The wind tunnel tests showed that the SOS measured by the probe and conventional instrumentation agreed within ± 1.5%. This establishes that the technique is capable of accurately measuring the speed of sound, which is the primary variable to calculate the flow composition. The technique can also be used to measure volume. Although the wind tunnel tests were not specifically designed to assess the accuracy of the flow rate measurement, comparisons were made between the flow velocities given by the probe and reference measurements. The additional motivation was to assess the ability of the probe to monitor volume flow/mass flow at high Mach numbers where only shorter straight sections are available. The flow velocities measured by the probe agreed with those calculated using the wind tunnel instrumentation (wall-static taps) within the estimated uncertainty levels introduced by the flow blockage and profile distortions. Additional tests are planned to assess flow rate accuracy. Effort is continuing to study steam flows representative of exhaust of low pressure steam turbines in steam plants.Copyright © 2003 by ASME