RU38564U1 - Gastrointestinal Bleeding Relapse Probe Detector - Google Patents

Abstract

The utility model relates to medicine, in particular to surgery, and is intended for the early diagnosis of relapse of gastrointestinal bleeding.

We were the first to propose a device called a “Probe Detector for the early diagnosis of recurrence of gastrointestinal bleeding” (hereinafter referred to as a “probe detector”), which allows for indication of a small volume of blood directly in the lumen of the stomach, regardless of the patency of the probe. The probe detector is a nasogastric tube in which two fibers are located inside the lumen, terminating at a distance of 1.5 cm from the reflector inside the working end. One of the optical fibers (active) is connected to a light source; the second (perceiving) - with a photo-optical sensor.

Description

The utility model relates to medicine, in particular to surgery, and is intended for the early diagnosis of relapse of gastrointestinal bleeding.

Usually, a nasogastric tube is used to diagnose relapse of gastrointestinal bleeding [1]. With the development of a relapse of gastrointestinal bleeding, blood is released by a probe from the cavity of the stomach, which is recorded visually. Meanwhile, the outflow of blood from the stomach begins only with a sufficiently large volume of at least 500 ml, which does not allow timely diagnosis of hemorrhage recurrence. Often, even with a significant rate of bleeding, the probe lumen is closed by a blood clot and the diagnosis of repeated bleeding becomes impossible. In this case, the recurrence of hemorrhage is recorded with delay only by clinical signs - lowering blood pressure, repeated bloody vomiting, repeated melena. A delay in the diagnosis of relapse leads to the development of hemorrhagic shock, which leads to high mortality in this category of patients [2].

Sometimes a relapse of hemorrhage is recorded during control fibrogastroduodenoscopy (FGDS) [3], but this is extremely reliable

the method does not allow for constant monitoring of the patient's condition. The intervals between endoscopic examinations are 6-24 hours; at this time, hemostasis quality control is completely absent.

We first proposed the device "Probe detector for early diagnosis of recurrence of gastrointestinal bleeding" (hereinafter referred to as the "probe detector"), which allows the indication of a small amount of blood directly in the lumen of the stomach, regardless of the patency of the probe. The probe-detector is a nasogastric tube in which two fibers are located inside the lumen, terminating at a distance of 1.5 cm from the metal reflector inside the “working” end. One of the optical fibers (active) is connected to a light source; the second (perceiving) - with a photo-optical sensor.

The proposed device is shown in figure 1, where:

1. Nasogastric tube

2. Active fiber

3. Perceiving optical fiber

4. Reflector

5. Side hole

6. Light source - semiconductor laser

7. Photoptic sensor

8. Light signaling

9. Sound alarm

10. Sealed input of optical fibers 11. Channel for washing the probe

12. The adapter for connection to an electric network ≈ 220 V

The proposed probe-detector for relapse of gastrointestinal bleeding consists of a polyvinyl chloride nasogastric tube (1) with a side opening (5) near the “working” end; two parallel polyethylene optical fibers (2,3) in the sheath, passed through the inner lumen of the catheter; polished metal reflector (4) on the “working” end of the catheter; a source of low-energy laser radiation (b); photo-optical sensor (7). The input of the optical fibers into the catheter is sealed (10); a separate channel is provided for gastric lavage (11). The optical fibers are located at a distance of 1.5 cm from the reflector inside the working end of the nasogastric tube. The light source and the photo-optical sensor are combined in the photo-optical relay of the Minsk Optical and Mechanical Plant “PHOTOELECTRIC SWITCH E 3S-X3CE4”. It is possible to use other electron-optical sensors. Signal sound (9) and light (8) devices are mounted in the photo-optical sensor. The device through an adapter (12) is connected to a household electricity network ≈ 220 V.

The action of the proposed model is as follows. After emergency endoscopy, endoscopic hemostasis and gastric washing

from the contents of the probe, the detector is conducted into its lumen. The photo-optical sensor is connected to a current source. A low-energy laser mounted in the sensor delivers light to one of the optical fibers. The laser beam from the end of the fiber is emitted into the lumen of the nasogastric tube in the “working” part of it. The reflector is installed at a distance of 1.5 cm from the ends of the optical fibers (see Appendix 1). Reflecting from the polished reflector, the light is captured by the second light guide and through it falls on the photo-optical sensor (Figure 2). While the contents in the stomach are absent or it has a transparent character (gastric juice), the light beam in the device remains continuous, which is detected by the photo-optical sensor. When a relapse of gastrointestinal bleeding has begun (blood appears in the lumen of the stomach), the contents in the stomach become opaque, it flows into the lumen of the detector probe through the side hole and opens the optical axis. The interruption of the light flux is detected by a photo-optical sensor, which includes sound and light indication (Figure 3).

The advantage of the proposed device is the possibility of early diagnosis of relapse of gastrointestinal bleeding when a minimal amount of blood (up to 1 ml) appears in the stomach under conditions of constant monitoring of the patient's condition.

[1] - Rozanov B.S. Gastric bleeding and their surgical treatment. MedGIZ, 1960. -M. -289 p.

[2] - Esperov B.N., Tsyganok N.S. Surgery

bleeding gastroduodenal ulcer // Surgery. - 1990.-№3. - S. 43-46.

[3] - Pantsirev Yu.M. Acute bleeding from the upper section

digestive tract - A guide to emergency surgery of the abdominal organs. - M. - Medicine, 1998 .-- 238 p.

Appendix 1 Determination of the "working distance" of the probe-detector for early diagnosis of relapse of gastrointestinal bleeding

In the experiment, the sensitivity of the probe was studied in media with different transparency, with different distances from the ends of the optical fibers to the reflector (working distance), and the minimum sensor response distance was determined. The radiation power at the end of the fiber was 1 mW. The radiation of the optical range with a wavelength of red light λ = 630 nm was used. The maximum resolving distance from the end of the optical fibers to the reflector in a transparent medium (distilled water) turned out to be 4.5 cm. Solutions of various transparency containing blood were made.

To determine the transparency of the solutions, a KFK-3 photoelectric photometer was used. In various media, a transmittance τ was determined using a photometer: where f is the luminous flux passing through the test medium; Ф _{0 -} light flux passing through a transparent medium - distilled water (parameters were determined by a photometer). In addition, the optical density D was calculated:

optical density was not calculated for opaque media.

Whole blood is a medium with a low transmittance, it triggered the photo-optical sensor from a minimum distance (from 0.2 cm). The following results were obtained in hemolized blood preparations (with the addition of distilled water) with different concentrations of hemoglobin (Hb) (Table 1):

Table 1
Calibration of the probe probe with hemolyzed blood products Hb concentration 100 g / l 75 g / l 50 g / l 25 g / l Transmittance 19% 38% 58% 77% Optical density -1.27 -1.58 -1.76 -1.89 Minimum distance 0.2 cm 0.5 cm 1.5 cm 3.0 cm sensor response

In accordance with the data obtained, it was concluded that a “working distance” of 1.5 cm is sufficient to indicate blood.

Claims (1)

A probe probe for early diagnosis of recurrence of gastrointestinal bleeding, including a nasogastric tube, characterized in that it is additionally equipped with a reflecting mirror inside at the working end, two fibers located in the probe’s lumen and ending at a distance of 1.5 cm from the mirror, one The light guide is connected to a light source, and the other to a photo-optical sensor.