Simplified Esophageal Electrocardiography Using Bipolar Recording Leads

1981 ◽  
Vol 95 (1) ◽  
pp. 14 ◽  
Author(s):  
STEPHEN C. HAMMILL
Keyword(s):  
Bipolar Recording

Neurophysiological effects of dorsal column stimulation in man and monkey

1974 ◽  
Vol 41 (2) ◽  
pp. 217-223 ◽  
Author(s):  
Sanford J. Larson ◽  
Anthony Sances ◽  
Donald H. Riegel ◽  
Glenn A. Meyer ◽  
Donald E. Dallmann ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Evoked Potentials ◽  
Evoked Potential ◽  
Intractable Pain ◽  
Current Application ◽  
Content Type ◽  
Bipolar Recording ◽  
Stimulating Electrodes ◽  
Recording Electrodes ◽  
Fine Print

✓ In 18 patients with cancer and intractable pain, capacitatively coupled pulses of 0.25 msec duration were delivered transcutaneously at 100 Hz to sets of five in-line electrodes implanted subdurally over the dorsal columns. Averaged somatosensory-evoked potentials were recorded from scalp electrodes before, during, and after application of current. All but one patient experienced relief of pain during stimulation, persisting for as long as several hours afterward. Eleven patients developed hyperactive deep reflexes, pathological reflexes, and decreased perception of joint rotation, pain, and touch below the level of current application. Somatosensory-evoked potential amplitudes were markedly reduced. All neurological findings returned to control values within 1 hour after each of repeated applications of current. Histological examination of spinal cord sections from four cancer patients showed no changes secondary to long-term current application. Similar currents were applied to the spinal cord of 15 monkeys with chronically implanted bipolar recording or stimulating electrodes over the lower, middle, and upper thoracic cord, in nucleus ventralis posterior lateralis (VPL), and over the sensory motor cortex (SMC). With application of current, the responses in VPL and SMC to peripheral stimulation were abolished. Evoked potential responses were abolished between bipolar stimulating electrodes and bipolar recording electrodes separated by the five in-line electrodes used to supply the 100 Hz current. However, when both stimulating and recording electrodes were either above or below the five in-line electrode set, evoked responses were unaffected. The findings indicate that applied currents blocked neuronal transmission by producing local changes in the cord. The prolonged alteration of cerebral evoked potentials and relief of pain, however, could also be related to involvement of supraspinal neurons.

Restating the importance of bipolar recording in subcortical nuclei

2006 ◽  
Vol 117 (2) ◽  
pp. 474-475 ◽  
Author(s):  
Richard Wennberg ◽  
Andres M. Lozano
Keyword(s):  
Bipolar Recording ◽  
Subcortical Nuclei

THE RELATIONSHIP BETWEEN ELECTRICAL AND MECHANICAL ACTIVITY OF THE SMALL INTESTINE OF DOG AND MAN

1960 ◽  
Vol 38 (7) ◽  
pp. 777-801 ◽  
Author(s):  
E. E. Daniel ◽  
B. T. Wachter ◽  
A. J. Honour ◽  
A. Bogoch
Keyword(s):  
Small Intestine ◽  
Electrical Activity ◽  
Slow Wave ◽  
Action Potentials ◽  
Extracellular Fluid ◽  
Slow Waves ◽  
Mechanical Activity ◽  
Electrical Currents ◽  
Bipolar Recording ◽  
Balloon Distention

Electrical activity of the small intestine of man and of dogs has been studied using monopolar recording techniques and spread of electrical activity in the small intestine of the dog using a bipolar recording technique. Motility was studied simultaneously. Electrical activity consisted of slow waves and action potentials which occurred when contractions were present. Action potentials were not conducted but slow waves sometimes spread aborally for short distances. Particular attention was paid to the relation of slow waves to action potentials and to motility. No consistent alteration in the frequency or configuration of slow waves was found associated with the occurrence of action potentials and motility, although serotonin or epinephrine altered slow wave frequency slightly. Slow waves usually were increased in amplitude during periods when motility and action potentials were occurring (during eating or balloon propulsion; after the administration of serotonin, neostigmine, physostigmine, or morphine). Slow wave amplitudes usually were diminished when motility was inhibited (by balloon distention; after administration of epinephrine, etc.). Action potentials tended to occur in phase with the slow waves, when the muscle electrode was positive relative to the indifferent electrode, but this was not always so during nonpropulsive contractions. There was also a correlation between the occurrence of distal spread of slow waves over the duodenum and upper jejunum and the ability of the intestine in this region to respond to balloon distention by propulsion.In the dog, body temperature consistently affected slow waves. A decrease of 10 °C diminished their frequencies to less than one-half and diminished their amplitude. Slow waves occurred at similar frequencies and with regular conduction after large doses of nicotine or atropine. Dibenzyline, dichloroisopropyl-norepinephrine, and vagotomy did not markedly alter slow wave frequencies. These findings and those in our studies with microelectrodes indicate that the slow waves are myogenic in origin, and represent electrical currents in the extracellular fluid initiated by periodic depolarizations of muscle cells of the small intestine.

Construction of a multipolar electrode system referenced and anchored to endocardium for study of arrhythmias

1986 ◽  
Vol 250 (3) ◽  
pp. H530-H536
Author(s):  
S. J. Worley ◽  
W. M. Smith ◽  
R. E. Ideker
Keyword(s):  
Ventricular Arrhythmias ◽  
Electrode System ◽  
Left Ventricular ◽  
The Body ◽  
Left Ventricular Cavity ◽  
Histological Studies ◽  
Ventricular Cavity ◽  
Bipolar Recording ◽  
Nylon Line

We developed a Teflon plunge electrode system (Teflon plunge) with important advantages over currently used electrodes. The Teflon plunge consists of an anchor-introducer (anchor) attached to the tip of an 0.8-mm diam epoxy-filled Teflon tube supporting six bipolar recording sites. The plunge is inserted through the myocardium into the ventricular cavity perpendicular to the epicardium. Once in the left ventricular cavity the anchor at the tip of the plunge pivots perpendicular to the long axis of the plunge and seats on the endocardium. It is maintained in position with a 4-0 nylon line (line) that extends from its attachment to the anchor through the body of the plunge to the epicardial end where it is secured with a Ligaclip. Thus the electrode contacts are placed a predetermined distance from the endocardium. When the Ligaclip is released, the plunge is removed from the heart leaving the line in the track of the electrode attached to the anchor as a marker for histological studies. The Teflon plunge will facilitate the evaluation of the role of the endocardium in ventricular arrhythmias by locating recording sites a stable, known distance from the endocardium and by marking the electrode track for histological studies.

The Electrical and Mechanical Events of Neuro-Muscular Transmission in the Cockroach, Periplaneta Americana (L.)

1950 ◽  
Vol 27 (1) ◽  
pp. 1-13
Author(s):  
KENNETH D. ROEDER ◽  
ELIZABETH A. WEIANT
Keyword(s):  
Structural Changes ◽  
Periplaneta Americana ◽  
Mechanical Response ◽  
Motor Nerve ◽  
Potential Gradient ◽  
Positive Sign ◽  
Direct Stimulation ◽  
Bipolar Recording ◽  
Nerve Muscle ◽  
Muscle Potential

1. A nerve-muscle preparation in the metathorax of the cockroach is described. It consists of the second tergal muscle of the trochantin (muscle 162 of Carbonell) innervated by a branch of nerve 3 A. Electrical changes are recorded from electrodes on the muscle surface, and the onset of contraction is registered by the stylus of a piezo-electric pick-up. 2. With low (3-5 per sec.) stimulation rates at room temperature the neuromuscular delay is less than 1.2 msec., and the latent period of contraction about 3.0 msec. The muscle potential is 4-5 msec. in duration, positive in sign at the muscle surface, and monophasic in form with either monopolar or bipolar recording. During excitation a potential gradient develops along the muscle, the greatest positivity being in the middle near the point of nerve entry. 3. Neither electrical nor mechanical response show gradations with changes in stimulus strength or frequency. No facilitation is evident, and the response appears to be due to stimulation of a single quick motor nerve fibre. 4. In order to study the effects of direct stimulation nerve 3 was sectioned and allowed to degenerate. All trace of the peripheral nerve stump was lost after 3 days, when the muscle became completely inexcitable to all forms of electrical stimulation. There were no gross structural changes which would account for this loss of excitability. 5. It is concluded that the recorded muscle potential in the cockroach is analogous to the vertebrate end-plate potential, being the sum of local muscle potentials developing simultaneously in several fibres, and sequentially at several innervation points along the same fibre. Conduction within the muscle is carried out entirely by motor nerve fibres. 6. Possible causes of the positive sign of the muscle during activity are discussed.

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