The aim of this study was to compare in vitro various methods for recording intestinal sensitivity and compliance. Relationships between volume and pressure were determined in segments of penrose tubing and pig gut ("artificial intestine') using pressure increments of 2 mmHg (0-24 mmHg). We tested two direct methods of distension of the entire segments (by syringe inflation and the Mayo barostat); we also used three different balloon devices for indirect distension (a 10 cm polyethylene barostat bag, a 10 cm latex condom balloon and a 6 cm latex condom balloon). Maximal distending diameters of the recording systems were measured by injecting from 0 to 160 mL of air. The elastic properties of the balloons were also tested by distensions in air and in rigid tubes. All recording systems accurately detected a lesser compliance of the penrose drain as compared to pig gut. In absolute terms, only the compliance measured with a polyethylene barostat bag distended with a syringe was not different from the compliance of the segment as measured directly. The bellows of our barostat and the latex balloons had significant intrinsic compliances which interfered with the recorded pressure-volume curves. On the other hand, highly compliant plastic bags recorded most faithfully the compliance of artificial gut and that of non-compliant rigid tubes. For comparable volumes of distension, external diameters were larger with the 6 cm latex balloon than with the 10 cm latex balloon or the 10 cm polyethylene barostat balloon. A polyethylene bag distended with a non-compliant air injector (syringe) reflected most accurately the pressure-volume relationships of tubular structures. The different maximal diameters assumed by the three distending devices may explain, in part, why lower volumes of distension are required to elicit symptoms with smaller distending balloons in vivo.

Animals↗

PubMed1995

Diagnosis and treatment of pancreatic and ampullary cancer.

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Adenocarcinoma↗

PubMed1992

Effect of glyceryl trinitrate on proximal stomach musculature in normal volunteers.

UNLABELLED: The effect of GTN on stomach is unknown although there is evidence that nitric oxide, the active component of GTN have a mediator role in the upper gastrointestinal tract. By the use of a newly developed barostat technique it was investigated the effect of GTN on gastric fundal tone and contractions. METHOD: measurements were done 1 hour before an 1 hour after the administration of either 500 micrograms sublingual GTN and 5 mg buccal GTN or a placebo in 7 healthy individuals (14 experiments) by recording variations in the volume of air within an intragastric bag that was maintained at a constant pressure of 12 mmHg by the barostat. RESULTS: a significant increase in intrabag volume of 99.74 +/- 28.34 ml (mean +/- SEM) (p < 0.01) was recorded after GTN administration; a not significant (p > 0.01) increase in volume of 24.34 +/- 16.23 ml was after placebo. There was no significant difference between the frequency of contractions before and after drug or placebo administration. CONCLUSION: after systemic and constant administration of GTN a constant reduction in gastric fundal tone is produced with no change of fundal contractions.

Adult↗

PubMedDate not supplied

[COPD or why COPD is not as asthma ?].

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Adrenal Cortex Hormones↗

PubMedDate not supplied

The flexible bronchoscopic approach to lung volume reduction.

Surgical lung volume reduction is effective in patients with chronic obstructive pulmonary disease (COPD) because it improves the ratio between residual lung volume and total lung volume. The same effect may be achieved by inducing an iatrogenic atelectasis in one or more lung lobes using a flexible bronchoscopic approach. This article discusses the origin and the progress, up to date, of this new minimally invasive flexible bronchoscopic approach.

Bronchoscopes↗