scholarly journals Electrical activity of the diaphragm (Edi) values and Edi catheter placement in non-ventilated preterm neonates

2013 ◽  
Vol 33 (9) ◽  
pp. 707-711 ◽  
Author(s):  
H Stein ◽  
R Hall ◽  
K Davis ◽  
D B White
2021 ◽  
Author(s):  
Alison Protain ◽  
Kimberly Firestone ◽  
Saima Hussain ◽  
Daniel Lubarsky ◽  
Howard Stein

Abstract Neonates with apnea of prematurity (AOP) deteriorate clinically because CPAP often provides inadequate support during apnea. NAVA provides proportional ventilator support from the electrical activity of the diaphragm. When NAVA level is 0 cmH20/mcV (NN0), patients receive minimal support when breathing and backup ventilation when apneic. This study addresses feasibility of NN0 and time spent in back up ventilation. This was a prospective, two center, observational study of preterm neonates on NN0 for AOP. Ventilator data were downloaded for 24 hours. Number of Clinically Significant Events (CSEs) and switches to back up were collected. Statistics were paired t-test. There were twenty-eight subjects with gestational age of 25 + 1.8 weeks; study age 28 ± 23 days. Number of events were 4±4.39 per 24 hours. Subjects were on NN0 approximately 90% each minute, back-up mode 2.5±1.1 times/minute with 10.6±7.2% in back-up. Conclusion: Preterm neonates on NAVA level 0 had few clinically significant events with minimal time in back up ventilation.


Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.


Author(s):  
Frank J. Longo

Measurement of the egg's electrical activity, the fertilization potential or the activation current (in voltage clamped eggs), provides a means of detecting the earliest perceivable response of the egg to the fertilizing sperm. By using the electrical physiological record as a “real time” indicator of the instant of electrical continuity between the gametes, eggs can be inseminated with sperm at lower, more physiological densities, thereby assuring that only one sperm interacts with the egg. Integrating techniques of intracellular electrophysiological recording, video-imaging, and electron microscopy, we are able to identify the fertilizing sperm precisely and correlate the status of gamete organelles with the first indication (fertilization potential/activation current) of the egg's response to the attached sperm. Hence, this integrated system provides improved temporal and spatial resolution of morphological changes at the site of gamete interaction, under a variety of experimental conditions. Using these integrated techniques, we have investigated when sperm-egg plasma membrane fusion occurs in sea urchins with respect to the onset of the egg's change in electrical activity.


2014 ◽  
Vol 19 (5) ◽  
pp. 3-12
Author(s):  
Lorne Direnfeld ◽  
David B. Torrey ◽  
Jim Black ◽  
LuAnn Haley ◽  
Christopher R. Brigham

Abstract When an individual falls due to a nonwork-related episode of dizziness, hits their head and sustains injury, do workers’ compensation laws consider such injuries to be compensable? Bearing in mind that each state makes its own laws, the answer depends on what caused the loss of consciousness, and the second asks specifically what happened in the fall that caused the injury? The first question speaks to medical causation, which applies scientific analysis to determine the cause of the problem. The second question addresses legal causation: Under what factual circumstances are injuries of this type potentially covered under the law? Much nuance attends this analysis. The authors discuss idiopathic falls, which in this context means “unique to the individual” as opposed to “of unknown cause,” which is the familiar medical terminology. The article presents three detailed case studies that describe falls that had their genesis in episodes of loss of consciousness, followed by analyses by lawyer or judge authors who address the issue of compensability, including three scenarios from Arizona, California, and Pennsylvania. A medical (scientific) analysis must be thorough and must determine the facts regarding the fall and what occurred: Was the fall due to a fit (eg, a seizure with loss of consciousness attributable to anormal brain electrical activity) or a faint (eg, loss of consciousness attributable to a decrease in blood flow to the brain? The evaluator should be able to fully explain the basis for the conclusions, including references to current science.


2001 ◽  
Vol 120 (5) ◽  
pp. A209-A209
Author(s):  
G RIEZZO ◽  
R CASTELLANA ◽  
T DEBELLIS ◽  
F LAFORGIA ◽  
F INDRIO ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document