Abstract 312: "Stand Clear" Belongs to the Past: A Solution for Safe Hands-on Defibrillation

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Jakob E Thomsen ◽  
Graham W Petley ◽  
Bo Løfgren ◽  
Charles D Deakin
Keyword(s):  
Leakage Current ◽  
Chest Compression ◽  
Chest Compressions ◽  
Case Scenario ◽  
Worst Case ◽  
The Past ◽  
Worst Case Scenario ◽  
Hands On ◽  
Class 1 ◽  
Additional Point

Introduction: Interruptions to chest compressions during defibrillation reduce the chances of subsequent ROSC and successful defibrillation. Safe hands-on defibrillation (HOD) will allow uninterrupted chest compression during defibrillation and may improve resuscitation success. We tested the safety of rescuer contact with the patient (at the waist) whilst additionally wearing electrical insulating gloves during clinical defibrillation; a worst case scenario. Materials and Method: Leakage current flowing from the patient to the ‘rescuer’ during defibrillation of patients undergoing elective defibrillation was measured. The ‘rescuer’ remained in contact with the patient during defibrillation, wearing Class 1 electrical insulating gloves while simulating an inadvertent contact with the patient, through an additional wired contact between rescuer’s waist and patient. The results were compared with an international safety threshold of 1 mA. Results: Data from 67 shocks of variable biphasic energy from a total of 50 patients was recorded. The median leakage current from all defibrillations was 30 μA, (range: 7 - 164). Of the 34 of the shocks delivered at 360J the median leakage current was 62 μA (range: 13 - 164), all below the safety threshold of 1 mA. Conclusion: This study demonstrates that leakage current through the rescuer is within a safe threshold to allow hands-on defibrillation when using electrically insulated gloves and in the presence of an additional point of contact with the patient

Abstract 133: Electrical Insulating Gloves for Safe Hands-on Defibrillation Do Not Compromise the Quality of Chest Compressions

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Jakob E Thomsen ◽  
Martin Harpsø ◽  
Graham W Petley ◽  
Svend Vittinghus ◽  
Charles D Deakin ◽  
...  
Keyword(s):  
Clinical Examination ◽  
Chest Compression ◽  
Electrical Insulation ◽  
Compression Rate ◽  
Chest Compressions ◽  
Compression Depth ◽  
Resuscitation Guidelines ◽  
Hands On ◽  
Class 1

Introduction: We have recently shown that Class 1 electrical insulating gloves are safe for hands-on defibrillation. Continuous chest compressions during defibrillation reduce the peri-shock pauses and increase the subsequent chance of successful defibrillation. In this study we have investigated the effect of these electrical insulation gloves on the quality of chest compressions, compared with normal clinical examination gloves. Methods: Emergency medical technicians trained in 2010 resuscitation guidelines delivered uninterrupted chest compressions for 6 min on a manikin, whilst wearing Class 1 electrical insulating gloves or clinical examination gloves. The order of gloves was randomized and each session of chest compressions was separated by at least 30 min to avoid fatigue. Data were collected from the manikin. Compression depth and compression rate were compared. Results: Data from 35 participants are shown in Figure 1. There was no statistically significant difference between Class 1 electrical insulating gloves in chest compression depth (median±range: 45 (28-61) vs 43 (28-61) p=0.69) and chest compression rate (113 (67-150) vs 113(72-145), p=0.87) when compared to clinical examination cloves. Conclusion: These preliminary data suggest that the use of Class 1 electrical insulation gloves does not reduce the quality of chest compressions during simulated CPR compared to clinical examination gloves.

Abstract 63: Hands-On Defibrillation: An Analysis of Current Flow Through Rescuers In Contact With Patients During Biphasic External Defibrillation

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Michael S Lloyd ◽  
Eric L Krivitsky ◽  
Paul F Walter ◽  
Jonathan J Langberg
Keyword(s):  
Leakage Current ◽  
Current Flow ◽  
Chest Compressions ◽  
Case Scenario ◽  
Storage Oscilloscope ◽  
Worst Case ◽  
Shock Delivery ◽  
Digital Storage ◽  
Posterior Shoulder ◽  
Flow Through

Background: During cardiopulmonary resuscitation, the need for rescuers to stand clear before a shock is delivered invariably interrupts chest compressions. Brief interruptions like these reduce the efficacy of defibrillation in animal models. Current flow through a rescuer in contact with a patient being shocked with modern biphasic waveforms and adhesive patch electrodes has not been investigated. We hypothesized that leakage current is low through a rescuer performing chest compressions at the time of shock delivery. Methods: During 18 elective cardioversions using truncated exponential biphasic waveforms (median energy 200 joules, range 100 –360 joules), an investigator serving as the rescuer placed a gloved hand on the patient’s anterior chest immediately adjacent to the defibrillating patch with approximately 20lbs of pressure to simulate chest compressions. Skin electrodes were used to connect the rescuer’s thigh to the patient’s posterior shoulder, simulating a worst-case return current pathway. During shock delivery, voltage and current through the rescuer (hand to thigh) were recorded using a digital storage oscilloscope during the shock delivery. Results: In no cases were shocks perceptible to the rescuer. Mean patient transthoracic impedance was 57 +/− 14 ohms (range 36 –79 ohms). Potential differences in volts (V) between the rescuer’s wrist and thigh ranged from 1.7 to 14 V (mean 6.7 +/− 2.7 V). Calculated impedances through rescuers ranged from 8,190 to 100,400 ohms (mean 30,100 +/− 20,400 ohms). The average leakage current flowing through the rescuer’s body for each phase of the shock waveform was 273 +/−191 microamperes (range 1 to 910 microamperes). All measured values in our series were well below 2,500 microamperes, an accepted safety standard for earth-leakage current in medical devices. Conclusions: Even in a simulated worst-case scenario, a rescuer performing chest compressions during biphasic external defibrillation is exposed to low levels of leakage current. Our findings demonstrate the safety and feasibility of uninterrupted chest compressions during shock delivery, which may enhance the efficacy of defibrillation and cardiocerebral perfusion.

Reducing Probabilistic Weather Forecasts to the Worst Case Scenario: Anchoring Effects

2008 ◽  
Author(s):  
Sonia Savelli ◽  
Susan Joslyn ◽  
Limor Nadav-Greenberg ◽  
Queena Chen
Keyword(s):  
Case Scenario ◽  
Worst Case ◽  
Weather Forecasts ◽  
Worst Case Scenario ◽  
Anchoring Effects

scholarly journals A Comparison of Match Demands Using Ball-in-Play versus Whole Match Data in Professional Soccer Players of the English Championship

Sports ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 76
Author(s):  
Dylan Mernagh ◽  
Anthony Weldon ◽  
Josh Wass ◽  
John Phillips ◽  
Nimai Parmar ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Soccer Players ◽  
Training Methods ◽  
Case Scenario ◽  
Worst Case ◽  
Repeated Measures Design ◽  
Worst Case Scenario ◽  
Professional Soccer ◽  
Peak Match ◽  
Playing Time

This is the first study to report the whole match, ball-in-play (BiP), ball-out-of-play (BoP), and Max BiP (worst case scenario phases of play) demands of professional soccer players competing in the English Championship. Effective playing time per soccer game is typically <60 min. When the ball is out of play, players spend time repositioning themselves, which is likely less physically demanding. Consequently, reporting whole match demands may under-report the physical requirements of soccer players. Twenty professional soccer players, categorized by position (defenders, midfielders, and forwards), participated in this study. A repeated measures design was used to collect Global Positioning System (GPS) data over eight professional soccer matches in the English Championship. Data were divided into whole match and BiP data, and BiP data were further sub-divided into different time points (30–60 s, 60–90 s, and >90 s), providing peak match demands. Whole match demands recorded were compared to BiP and Max BiP, with BiP data excluding all match stoppages, providing a more precise analysis of match demands. Whole match metrics were significantly lower than BiP metrics (p < 0.05), and Max BiP for 30–60 s was significantly higher than periods between 60–90 s and >90 s. No significant differences were found between positions. BiP analysis allows for a more accurate representation of the game and physical demands imposed on professional soccer players. Through having a clearer understanding of maximum game demands in professional soccer, practitioners can design more specific training methods to better prepare players for worst case scenario passages of play.

Legal adaptability in Elbonia

2006 ◽  
Vol 2 (4) ◽  
pp. 393-408 ◽  
Author(s):  
Mathias M. Siems
Keyword(s):  
Empirical Data ◽  
Baltic States ◽  
Case Scenario ◽  
Worst Case ◽  
Worst Case Scenario ◽  
The Law

Law has to be able to respond to new or changing circumstances. This ‘legal adaptability’ may be more important than details in the ‘law as such’. However, its meaning and its significance have not yet been analysed in detail. Thus, legal adaptability will be examined in this article. It looks at the worst case scenario by discussing a fictional country (Elbonia) where legal adaptability is poor, and identifies the main adaptability criteria. By using empirical data from the three Baltic States (Lithuania, Latvia, Estonia), it also provides an example of how to ascertain the degree of legal adaptability of particular countries.

Discussion of the Worst Case Scenario of FLD0

2000 ◽  
Author(s):  
Naji Arwashan
Keyword(s):  
Simple Formula ◽  
Forming Limit Diagram ◽  
Forming Limit ◽  
Vertical Position ◽  
Engineering Practice ◽  
Case Scenario ◽  
Worst Case ◽  
Grid Analysis ◽  
Worst Case Scenario ◽  
Minimum Value

Abstract The Forming Limit Diagram is used in circle grid analysis to check the safety of a formed panel. The shape of the Forming Limit Diagram for steel is always the same, it is only the vertical position of the diagram that varies depending on the value of FLD0. For steel, FLD0 is widely accepted to be dependent on the thickness and n value which are both inherently indeterministic, and can exhibit variations, small or large, depending on the manufacturing process. To account for this variability in determining the safety of a formed panel, the engineering practice in many companies is to use a minimum value for FLD0 called Worst Case Scenario, because it is calculated using minimum values for both t and n. This paper presents a different and better approach to calculate the minimum value of FLD0. The approach is based on probabilistic concepts, and allows the calculation of a minimum value for FLD0 that is related to a certain probability of occurrence. The derivation technique used in the paper is borrowed from Reliability Analysis and tailored to solve our problem. The derivation leads to a simple formula that can be easily used. The minimum value of FLD0 calculated according to the paper is more accurate than the Worst Case Scenario, and provides better cost saving since it is always greater than the Worst Case Scenario value.

Genetic Family Histories: An Aid to Social Work Assessment

1993 ◽  
Vol 74 (4) ◽  
pp. 195-206 ◽  
Author(s):  
Barbara Bernhardt ◽  
Julia B. Rauch
Keyword(s):  
Social Work ◽  
Genetic Services ◽  
Case Scenario ◽  
Worst Case ◽  
Worst Case Scenario ◽  
Family Histories ◽  
Work Assessment ◽  
Focus Depth ◽  
Service Training ◽  
Agency Design

The focus, depth, and use of genetic family histories vary depending on the agency purpose and the client's presenting problem. Failure to obtain genetic family histories can result in inaccurate assessment and incomplete or misdirected services. In the worst-case scenario, failure to obtain such information and to advise clients of available genetic services are potential grounds for malpractice and wrongful-adoption suits. The authors discuss approaches to obtaining and recording genetic family histories and present criteria for referral to genetic services. The authors recommend that agency administrators consider consulting with a genetic professional to determine the appropriate focus of genetic family histories within the agency, design a protocol, and arrange in-service training in use of the protocol.

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