RU2339409C1 - Method for continuous anesthesia by xenon during cardiac surgery operations in conditions of artificial circulation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention concerns medicine, namely anesthesiology and cardiosurgery and can be used as the anesthesiology agent at surgical interventions on open heart in the conditions of an artificial circulation. For this purpose spend anaesthesia by xenon with the minimum stream to the patient. Then after the beginning of an artificial circulation carry out switching of a rebreathing system of the narcotic-respiratory apparatus from an endotracheal tube to entrance gas port of an oxygenator of a contour of an artificial circulation. Anaesthesia by xenon is continued in conditionally closed contour with the subsequent recycling of gas anaesthetic; to do that tightly connect the elastic tank from latex to the target gas port of an oxygenator. After restoration of cardiac activity and blood flow through lungs a rebreathing system of the is narcotic-respiratory apparatus connect back to an endotracheal tube, and continue anaesthesia by xenon before operation end under the standard scheme an anaesthesia xenon-saving up.

EFFECT: decrease of number of intra- and postoperative complications at the expense of continuous supply of xenon at all stages of operation, including the stage of an artificial circulation without necessity of transition to other kind of anaesthesia at this stage.

2 ex

Description

The invention relates to medicine, namely to cardiac surgery, to anesthetic management of open heart surgery in cardiopulmonary bypass (IR).

The known technology of xenon-saving anesthesia, which is based on the method of minimum flow anesthesia with xenon (Xe), carried out in a conditionally closed circuit, followed by recycling of the gas anesthetic [1].

This method is the closest to the claimed technical essence and the achieved result and is selected as a prototype.

The disadvantage of this method is that it does not make it possible to continue anesthesia with xenon after the onset of IR and requires a switch to another method of anesthesia, which reduces the convenience and safety of anesthetic management, increases the consumption of Xe.

The aim of the invention is to increase the safety of anesthetic management of open heart surgery in cardiopulmonary bypass.

This goal is achieved by the fact that after the start of IR during a cardiosurgical operation performed under conditions of minimum flow anesthesia with xenon, the respiratory circuit of the anesthesia-respiratory apparatus is switched from the endotracheal tube to the gas inlet of the oxygenator of the IR circuit and xenon anesthesia is continued in a conditionally closed circuit with subsequent gas anesthetic recycling. At the same time, an elastic latex reservoir is tightly connected to the outlet gas port of the oxygenator. The reservoir is necessary so that, thanks to the tightness, the respiratory circuit remains conditionally closed, as well as to ensure, due to its elasticity, the circulation in the respiratory circuit of the oxygen-xenon mixture during the “inhale” and “exhale” phases of the anesthesia-respiratory apparatus. After restoration of cardiac activity and blood flow through the lungs, the respiratory circuit of the anesthesia-respiratory apparatus is connected back to the endotracheal tube and xenon anesthesia is continued until the end of the operation according to the standard xenon-saving anesthesia scheme.

New in the proposed method is the minimum flow anesthesia with xenon during cardiac surgery in cardiopulmonary bypass followed by gas anesthetic recycling continuously by switching the respiratory circuit of the anesthesia-respiratory apparatus from the endotracheal tube to the inlet gas port of the oxygenator of the PC circuit and a sealed connection to the outlet gas port oxygenator elastic reservoir of latex, and after recovery of cardiac activity and blood flow through the lungs connecting the respiratory circuit of the anesthesia-respiratory apparatus back to the endotracheal tube and continuing xenon anesthesia until the end of the operation according to the standard xenon-saving anesthesia scheme.

New signs can reduce the number of intra- and postoperative complications due to the fact that before starting the IR method, it does not require switching to another method of anesthesia and artificial lung ventilation (mechanical ventilation) with pure oxygen to completely remove Xe from the patient’s body; after the termination of IR, denitrogenation is not required (breathing with pure oxygen up to 10 min) before xenon anesthesia begins.

Distinctive features showed in the inventive combination of new properties that are not explicitly derived from the prior art in this field and are not obvious to a specialist. No identical set of features was found in the analyzed literature. The proposed technical solution can be used in healthcare.

Based on the foregoing, this technical solution should be considered relevant to the conditions of patentability: "novelty", "inventive step", "industrial applicability".

The method is as follows.

After intravenous induction of anesthesia and intubation of the patient, artificial lung ventilation (ALV) is started with an anesthesia-respiratory apparatus, which makes it possible to use a conditionally closed circuit with minimal gas flow. Prior to supplying the xenon-oxygen mixture, denitrogenation is carried out - mechanical ventilation with pure oxygen for 10 minutes. Then, xenon anesthesia is started according to well-known principles (in a semicircuit followed by gas anesthetic recycling). After the initiation of cardiopulmonary bypass, the respiratory circuit of the anesthesia-respiratory apparatus is switched from the endotracheal tube to the gas inlet of the oxygenator of the cardiopulmonary bypass and xenon is continued anesthetized in a half-closed circuit, followed by gas anesthetic recycling, while the elastic reservoir from the latex is sealed with an elastic reservoir from the latex , and after restoration of cardiac activity and blood flow through the lungs, the respiratory circuit of anesthesia-respiratory the stomatal apparatus is connected back to the endotracheal tube and xenon anesthesia is continued until the end of the operation according to the standard xenon-saving anesthesia scheme [2, 3].

At all stages of xenon anesthesia, the ventilation modes are controlled based on the gas composition of the patient’s blood, and the composition of the xenon-oxygen mixture is monitored on the basis of the gas monitor GKM-03-INSOVT.

During xenon anesthesia at the IC stage, there is a theoretical possibility of the release (loss) of xenon from the blood into the atmosphere in a cardiotome reservoir, since the pathway for Xe elimination through the skin, wound surface, and open cavities is known [3]. In the proposed method, this process did not have clinical and economic value, the amount of xenon supplied to maintain anesthesia during PC did not differ from that at other stages of the operation.

Example 1. Patient G., 63 g. No. 324. Height 169 cm, weight 83 kg.

The main diagnosis. Coronary heart disease, FC III.

A coronary artery bypass grafting was performed under cardiopulmonary bypass.

After premedication, intravenous induction of anesthesia and intubation of the patient's trachea, mechanical ventilation by anesthesia-respiratory apparatus was started on a closed circuit. Against the background of continuing intravenous anesthesia, denitrogenation was performed by mechanical ventilation with 100% oxygen for 10 minutes. Then, xenon anesthesia was started according to well-known principles (in a conditionally closed circuit followed by gas anesthetic recycling). Xe was saturated at a total gas flow of 8 l / min (6 l / min - Xe and 2 l / min O ₂ ). After 2 minutes, upon reaching the surgical stage of anesthesia, the flow of O ₂ and Xe was reduced. Maintenance of anesthesia took place with a total gas flow of 0.3 l / min (0.1 l / min O ₂ and 0.2 l / min Xe). The average concentration of Xe in the gas mixture in the preperfusion period was 45%.

From the moment of cannulation of the aorta, Xe supply was stopped and a high flow of O ₂ (10 L / min) was used for dexenonization of the respiratory circuit. In parallel, propofol infusion was started at a rate of 4-12 mg / kg / h and fentanyl 2.5 μg / kg / h, providing anesthesia throughout the perfusion period.

After completion of cardiopulmonary bypass, denitrogenation of the respiratory circuit of 100% O ₂ was again performed and Xe was saturated and subsequent maintenance anesthesia was performed according to the method described above. At the end of the operation, the supply of Xe was stopped and the patient continued to be ventilated with 100% O ₂ for 7-10 minutes.

Recovery after surgery occurred after 20 minutes. The patient was extubated 2 hours after surgery. On day 3, the patient was transferred from intensive care.

Example 2. Patient Z., 58 l. I.b. No. 1245. Height 182 cm, weight 86 kg.

The main diagnosis. Coronary heart disease, FC III.

A coronary artery bypass grafting was performed under cardiopulmonary bypass.

After premedication, intravenous induction of anesthesia and intubation of the patient's trachea, mechanical ventilation by anesthesia-respiratory apparatus was started on a closed circuit. Against the background of continuing intravenous anesthesia, denitrogenation was performed by mechanical ventilation with 100% oxygen for 10 minutes. Then, xenon anesthesia was started according to well-known principles (in a conditionally closed circuit followed by gas anesthetic recycling). Xe was saturated at a total gas flow of 9 l / min (7 l / min - Xe and 2 l / min O ₂ ). After 2 minutes, the flow of O ₂ and Xe was reduced. Maintenance of anesthesia took place with a total gas flow of 0.4 l / min (0.15 l / min O ₂ and 0.25 l / min Xe). The average concentration of Xe in the gas mixture in the preperfusion period was 45%.

After the start of cardiopulmonary bypass, the respiratory circuit of the anesthesia-respiratory apparatus was switched from the endotracheal tube to the gas inlet port of the oxygenator of the IR circuit and xenon anesthesia was continued in a conditionally closed circuit, followed by gas anesthetic recycling under the control of blood gases and SpO ₂ . An elastic latex reservoir (bag) is hermetically connected to the outlet gas port of the oxygenator. The total gas flow amounted to 0.45 l / min (Xe - 0.3 l / min, O ₂ - 0.15 l / min). After restoration of cardiac activity and blood flow through the lungs, the respiratory circuit of the ventilator was connected back to the endotracheal tube and xenon anesthesia was continued until the end of the operation according to the standard scheme. The patient regained consciousness after 30 minutes. Extubation was performed 3 hours after surgery.

After 2 days, the patient was transferred to the general ward.

The method proposed by the authors was tested in 35 patients, which allows optimizing the anesthetic management of cardiosurgical operations under IR conditions, reducing the number of intra- and postoperative complications, improving the results of cardiac surgery, and reducing financial costs.

Bibliography

1. Kozlov I.A. Xenon anesthesia in high-risk patients. / I.A. Kozlov, S.V. Voronin, O.V. Stepanova // Scientific-practical conference "Xenon and xenon-saving technologies in medicine-2005". Sat doc. - M., 2005. - P.66-70.

2. Anesthesia xenon. / N.E. Burov, I.V. Molchanov, L.L.Nikolaev, V.N. Potapov, A.V. Korobov: Methodological recommendations. - M., 2003 .-- 13 p.

3. Burov N.E. Xenon in anesthesiology. Clinical and experimental research / N.E. Burov, V.N. Potapov, G.I. Makeev. - M .: Pulse, 2000 .-- S.140-142.

Claims (1)

The method of continuous xenon anesthesia during cardiosurgical operations in cardiopulmonary bypass using minimal flow xenon anesthesia performed in a conditionally closed circuit, followed by gas anesthetic recycling, characterized in that after the onset of cardiopulmonary bypass, the respiratory circuit of the anesthesia-respiratory apparatus is switched from the endotracheal tube to the inlet gas port of the oxygenator of the cardiopulmonary bypass and continue anesthesia with xenon in condition an explicitly closed circuit followed by gas anesthetic recycling, while an elastic latex reservoir is tightly connected to the outlet gas port of the oxygenator, and after restoration of cardiac activity and blood flow through the lungs, the respiratory circuit of the anesthesia-respiratory apparatus is connected back to the endotracheal tube and xenon anesthesia is continued until the operation is completed according to the standard scheme of xenon-saving anesthesia.