跳至主要内容

Restoring Coronary Perfusion Pressure before Defibrillation after Chest Compression Interruptions

Coronary perfusion pressure (CPP), also known as simply perfusion pressure, refers to the pressure gradient that drives coronary blood pressure, meaning the difference between the diastolic aortic pressure and the left ventricular end diastolic pressure. Sufficient CPP to provide myocardial reperfusion is required for defibrillation success after prolonged ventricular fibrillation (VF) cardiac arrest. However, when chest compression interruptions occur during cardiopulmonary resuscitation (CPR), there is a precipitous and sustained loss of CPP. The purpose of this study was to quantify the extent to which CPP recovers to pre-pause levels following chest compression interruptions.

This was a secondary analysis of prospectively collected data from two similar IACUC approved protocols. Animal handling and all surgical procedures were in strict compliance with the NIH Guide for the Care and Use of Animals. Both studies were conducted in our USDA-certified laboratory. A total of 105 female Yorkshire swine (weighing 30 - 35 kg) were included. After 10 minutes of untreated VF in the first study (n = 52) and 12 minutes of untreated VF in the second (n = 53), CPR began and epinephrine was administered approximately 2 minutes prior to a planned 10-second pause to record an artifact-free ECG waveform segment. Following this pause, CPR was resumed for 20 seconds prior to defibrillation. CPP data were extracted from three time points: 2 minutes after epinephrine delivery (CPP1); following the chest compression pause (CPP2); and immediately before defibrillation (CPP3). The primary outcome was defined as the ratio of CPP recovery (CPP3- CPP2) to the drop in CPP (CPP1-CPP2).

The results indicated that interrupting chest compressions to analyze the ECG VF rhythm caused a significant drop in CPP from 29.8 mmHg to 6.8 mmHg. Resuming CPR for 20 seconds prior to RS delivery restored 83% (95%CI: 78%, 86%) of the CPP lost during the CPR interruption.


Article by Timothy J. Mader, et al, from Tufts University School of Medicine, Springfield, USA.

Full access: http://mrw.so/4pxQby

Image by Dana Arena, from Flickr-cc.

评论

发表评论

此博客中的热门博文

Electron Spin and Proton Spin in the Hydrogen and Hydrogen-Like Atomic Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52202#.VIj7tMnQrzE Author(s) Stanisław Olszewski * Affiliation(s) Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland . ABSTRACT The mechanical angular momentum and magnetic moment of the electron and proton spin have been calculated semiclassically with the aid of the uncertainty principle for energy and time. The spin effects of both kinds of the elementary particles can be expressed in terms of similar formulae. The quantization of the spin motion has been done on the basis of the old quantum theory. It gives a quantum number n = 1/2 as the index of the spin state acceptable for both the electron and proton ...
发表评论
阅读全文

Remarks on the Complexity of Signed k-Domination on Graphs

Read  full  paper  at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53574#.VMnXsCzQrzE Author(s)    Chuan-Min Lee 1 , Cheng-Chien Lo 1 , Rui-Xin Ye 2 , Xun Xu 2 , Xiao-Han Shi 2 , Jia-Ying Li 2 Affiliation(s) 1 Department of Computer and Communication Engineering, Ming Chuan University, The First American University in Asia, Taoyuan, Taiwan, Chinese Taipei . 2 Department of Electronic Information Engineering, Fuzhou University, Fuzhou, China . ABSTRACT This paper is motivated by the concept of the signed k-domination problem and dedicated to the complexity of the problem on graphs. For any fixed nonnegative integer k, we show that the signed k-domination problem is NP-complete for doubly chordal graphs. For strongly chordal graphs and distance-hereditary graphs, we show that the signed k-domination problem can be solved in polynomial time. We also show that the problem is linear-time solvable for trees, interval graphs, and chord...
发表评论
阅读全文

A Review of Technical Requirements for High Penetration of Wind Power Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52361#.VJN8VcCAM4 Author(s)    Yuan-Kang Wu 1 , Tung-Ching Lee 2 , Ting-Yen Hsieh 2 , Wei-Min Lin 2 Affiliation(s) 1 Department of Electrical Engineering, National Chung-Cheng University, Chiayi, Taiwan . 2 Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan . ABSTRACT Renewable portfolio targets have been established in many regions around the world. Regional targets such as 20% renewable energy by year 2020 are not uncommon. As the levels of wind power penetration increase, there are many power system impacts. This work investigated possible challenges and technic...
发表评论
阅读全文