RU2016583C1 - Artificial blood circulation apparatus - Google Patents

Abstract

FIELD: medical engineering. SUBSTANCE: apparatus includes roll pump deriving drive from electric motor and plastic blood container divided by partitions in functional compartments, that is, venous, foam-suppression and arterial (pump chamber). Upper portion of pump chamber performs function of settler and lower portion of arterial compartment (delivery chamber) is integral part of roll pump. It is of double-layer type, with space between layers filled with air, and functions as damper. EFFECT: convenient blood circulation apparatus. 4 dwg

Description

 The invention relates to the field of medical equipment, namely to the development of portable portable heart-lung machines.

 Known devices for cardiopulmonary bypass, including devices for pumping blood ("mechanical heart") and regulating its gas composition (oxygenators). The most developed are bubble oxygenators based on the direct dispersion of blood by oxygen bubbles. Known apparatus developed in Czechoslovakia. This is an oxygenator made of polyvinyl chloride plastic compound made by high frequency welding. The apparatus contains: a filter, an antifoam sponge, a venous compartment, an oxygen supply tube, a tube for pouring blood into the oxygenator, a blood outlet to the arterial line, and a venous line. A disadvantage of the known device is that it does not meet the requirements of an ambulance.

 The closest technical solution is the heart-lung machine, which is a set of separate, hermetically sealed sterile plastic systems containing a removable plastic container with partitions that form compartments (venous, defoaming and arterial), with the lower part of the arterial compartment placed under the rollers of the pump rotor and is at the same time a discharge chamber. A disadvantage of the known device is the presence of a pump chamber 0.5 mm thick, through which pressure is transferred from the roller pump directly to the blood to push it into the recipient's arterial system, which leads to direct mechanical destruction of the blood cells, i.e. hemolysis of blood.

 The aim of the invention is to reduce blood hemolysis by expanding the area of action of the efforts of the roller pump on blood elements.

 This goal is achieved by the fact that in the cardiopulmonary bypass device, which contains a removable plastic blood vessel with three compartments - venous, defoaming and arterial with an injection chamber in its lower part, a line for supplying venous blood and oxygen and withdrawing arterial blood, a roller pump, moreover, the injection chamber is placed under the rollers of the pump, the injection chamber is made two-layer, and the cavity between the layers is filled with air.

 In FIG. 1 schematically depicts an oxygenator to a heart-lung machine; in FIG. 2 is a section AA in FIG. 1; in FIG. 3 - section of the working section of the pump chamber; in FIG. 4 - a general view of the model of the apparatus with oxygenator.

 The heart-lung machine contains: 1 - a venous compartment of a common plastic container, 2 - an antifoam compartment, 3 - an upper part of the pump chamber, 4 - an arterial compartment (pump chamber), 5 - a lower part of the pump chamber (pressure chamber), 6 - an air damper, 7 - venous tube (line for the supply of venous blood), 8 - tube for the supply of moistened oxygen (line for the supply of oxygen), 9 - line for the removal of arterial blood (tube for connecting to the arterial vessels of the patient), 10 - roller pump, 11 - capacity for blood (bag), 12 - cylindrical rollers of the pump. The proposed oxygenator is part of a cardiopulmonary bypass device, it contains: a roller pump 10, driven by an electric motor (not shown in the diagram), and a removable blood vessel 11. The blood vessel 11 is a removable plastic container, divided by partitions into functional compartments: venous compartment 1, antifoam compartment 2, arterial (pump chamber) 4, the upper part 3 of which serves as a settler, the lower part of the arterial compartment (pressure chamber) 5 is directly the second part of the roller pump 10 (the working section of the pump chamber) and is made two-layer, and the cavity 6 between the layers is filled with air and acts as a damper.

 A system of tubes is welded into the oxygenator, designed to connect this device to the patient's vascular system through venous and arterial catheters. Through the venous tube 7, the patient’s blood is discharged into the venous compartment 1 of the blood vessel 11, moistened oxygen is supplied here through the tube 8. The tube 9 with blood, enriched with oxygen, is connected to the arterial vessels of the patient. Capacity 11 with a system of tubes is included in the device as a separate sterile kit in sealed packaging and is intended for single use. The roller pump 10 has a rotating rotor with four cylindrical rollers 12 located in two mutually perpendicular planes.

 The device operates as follows: a cardiopulmonary bypass device is connected to the patient's vascular system through venous and arterial catheters. By venous catheters, the patient’s blood is drawn into the venous compartment 1 oxygenator (Fig. 1) due to the difference in levels. Here, humidified oxygen is supplied from a cylinder through a reducer and a dosimeter through a special tube 8. Foamed blood displaced into the anti-foam compartment 2, where the sponge is, moistened with an antifoam compound - an antiphon. After extinguishing the foam, oxygen-saturated blood flows through the filter into the pumping (arterial compartment) chamber 4, the upper part 3 of which serves as a sump. Using a roller pump 10 (Fig. 3), which has a rotating rotor with four cylindrical rollers 12 located in two mutually perpendicular planes, blood from the lower part of the pump chamber 5, which is the injection chamber and is made two-layer, and the cavity 6 between the layers is filled with air and performs the role of a damper (Fig. 3), is injected into the arterial line 9 and then into the patient’s artery.

 PRI me R. A prototype apparatus that has passed the tests is shown in FIG. 4. 12 experiments were conducted. It was found that the apparatus allows for adequate artificial assisted blood circulation in the productivity range up to 3 l / min. It maintains a predetermined high blood oxygenation (up to 90-96%), a blood temperature close to the initial one (1-2 ° C), provides low blood hemolysis (15-25 mg% per 1 h).

 For a comprehensive check of the apparatus, the latter was used to conduct various types of perfusion. When performing general perfusion, the apparatus was filled with donor blood or a blood substitute in the amount of 0.75-1.2 liters. In all cases, the apparatus made it possible to maintain an adequate regime of cardiopulmonary bypass with good gas exchange and gas dynamics. Perfusion lasted up to 5 hours and hemolysis even with a maximum perfusion duration turned out to be low (not more than 8-15 mg% per 1 hour), while the hemolysis level for the prototype was 25-30 mg% per 1 hour. Thus, the use of a two-layer pump chamber leads to reduction of hemolysis of blood during the operation of the heart-lung machine.

Claims (1)

 ARTIFICIAL BLOOD CIRCULATION APPARATUS, containing a removable plastic container for blood with three compartments - venous, antifoam and arterial with an injection chamber in its lower part, a line for supplying venous blood and oxygen and withdrawal of arterial blood, a roller pump, the injection chamber being placed under the pump rollers, characterized in that, in order to reduce hemolysis, the injection chamber is made two-layer, and the cavity between the layers is filled with air.

Images