Innovation in Urodynamics – Cystometry with Gas Perfused Catheters with Helium

Microdialysis catheters (CMA-60 with a polyamide dialysis membrane; 20,000-molecular wt cutoff) were either immersed in an external medium or were inserted in the quadriceps femoris muscle of healthy subjects, using perfusate with or without dextran 70. Varying the position of the outflow tubing induced changes in hydrostatic pressure. The sample volumes were significantly smaller in catheters perfused without a colloid compared with those perfused with a colloid [11–50% (in vitro) and 8–59% (in vivo) lower than in colloid-perfused catheters with the same position of the outflow tubing]. The sample volumes were also significantly smaller when the dialysis membrane was influenced by maximal hydrostatic pressure (above position) compared with minimal hydrostatic pressure (below position) [7–38% (in vitro) and 3–46% (in vivo) lower than in catheters in the below position with the same perfusion fluid]. In vivo, glucose concentration at a perfusion flow rate of 0.33 μl/min was higher when the catheters were perfused without a colloid [18–28% higher than in colloid-perfused catheters with the same position of the outflow tubing ( P < 0.001)] than with a colloid. A corresponding difference also tended to occur with lactate, glycerol, and urea. At 0.16 μl/min, the glucose concentration was the same irrespective of whether fluid loss had been counteracted by colloid inclusion or by lowering of outlet tubing. The mechanism behind the observed concentration difference is thought to be a higher effective perfusion flow rate when fluid loss is prevented at low-perfusion flows. This study shows that fluid imbalances can have important implications for microdialysis results at low-perfusion flow rates.

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Evidence of 5-HT participation in vagal inhibitory pathway to opossum LES.

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1978.234.3.e273 ◽

1978 ◽

Vol 234 (3) ◽

pp. E273 ◽

Cited By ~ 4

Author(s):

S Rattan ◽

R K Goyal

Keyword(s):

Lower Esophageal Sphincter ◽

Vagal Stimulation ◽

Inhibitory Pathway ◽

Lower Esophageal Sphincter Relaxation ◽

Esophageal Sphincter ◽

Local Stimulation ◽

Perfused Catheters ◽

Stimulation Of

Studies were performed in anesthetized opossums to investigate the nature of vagal-stimulated sphincter relaxation, which is resistant to antagonism by a combination of hexamethonium and atropine. The sphincter pressures were measured with water-filled and continuously perfused catheters anchored in the lower esophageal sphincter. Neither increase in the doses of hexamethonium and atropine nor addition of diphenhydramine further modified the vagal response. However, administration of 5-methoxydimethyltryptamine in the presence of hexamethonium and atropine abolished vagally stimulated sphincter relaxation. In animals pretreated with parachlorophenylalanine, addition of atropine and hexamethonium also abolished vagally stimulated sphincter relaxation. In the experiments in which lower esophageal sphincter relaxation on vagal stimulation was abolished, the local stimulation of intramural neurons still produced normal lower esophageal sphincter relaxation. These studies suggest that 5-hydroxytryptamine may participate in the vagal inhibitory pathway to the lower esophageal sphincter.

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Evaluation of esophagogastric junction relaxation by 4-second Integrated Relaxation Pressure in achalasia using High Resolution Manometry with water-perfused catheters

Neurogastroenterology & Motility ◽

10.1111/nmo.12415 ◽

2014 ◽

Vol 26 (11) ◽

pp. 1551-1556 ◽

Cited By ~ 10

Author(s):

V. Ortiz ◽

G. Poppele ◽

N. Alonso ◽

C. Castellano ◽

V. Garrigues

Keyword(s):

High Resolution ◽

Esophagogastric Junction ◽

High Resolution Manometry ◽

Integrated Relaxation Pressure ◽

Perfused Catheters

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Evolution of Esophageal Motility Testing: From Kronecker to Clouse

Foregut: The Journal of the American Foregut Society ◽

10.1177/26345161211044151 ◽

2021 ◽

Vol 1 (3) ◽

pp. 197-206

Author(s):

Andrew D. Grubic ◽

Peter F. Crookes

Keyword(s):

World War Ii ◽

Solid State ◽

Mayo Clinic ◽

Esophageal Motility ◽

Mechanical Function ◽

World War ◽

Technical Developments ◽

Boston University ◽

Perfused Catheters

Esophageal motility, the science of quantifying the mechanical function of the esophagus, was initiated by Hugo Kronecker in Germany in 1882. Little progress was made until after World War II, when motility studies began in the Mayo Clinic and Boston University. After 1960, several key figures promoted the science, including Lauran Harris, Don Castell, Jerry Dodds, Tom DeMeester, Peter Kahrilas, and Ray Clouse. All were inspirational teachers and mentors as well as scientists. The technical developments from balloons and perfused catheters to the current solid-state catheters and sophisticated software has provided insights which have helped physicians to treat patients with dysfunction of the esophagus with increasing success.

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Determination of the urethral stress profile with the aid of perfused catheters

Archives of Gynecology ◽

10.1007/bf02114728 ◽

1983 ◽

Vol 234 (1) ◽

pp. 67-73

Author(s):

W. Groß ◽

B. Festge ◽

O. -A. Festge ◽

K. Hajdu ◽

K. -D. Rosenbaum

Keyword(s):

Stress Profile ◽

Perfused Catheters

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