US-12622579-B2 - Medical device cleaning method and corresponding cleaning device and cleaning apparatus

US12622579B2US 12622579 B2US12622579 B2US 12622579B2US-12622579-B2

Abstract

A cleaning method for cleaning a surface of a medical device, the method including a contaminant removal phase including: (a) injecting a continuous flow of gas in an atomization chamber, through a first input of the atomization chamber; and (b) introducing a plurality of successive discharges of liquid in the atomization chamber through a second input of the atomization chamber, each discharge including a respective amount of liquid, a duration between two successive discharges being strictly greater than zero, thereby generating, at an output of the atomization chamber, a cleaning flow including, successively over time, liquid droplets suspended in gas, the cleaning flow being oriented towards the surface of the medical device.

Inventors

Daniel VINTELER
Timothée DUROUCHOUX

Assignees

PLASMABIOTICS

Dates

Publication Date: 20260512
Application Date: 20221118
Priority Date: 20211119

Claims (17)

1 . A cleaning method for cleaning a surface of a medical device, the method including a contaminant removal phase comprising: a. injecting a continuous flow of gas in an atomization chamber, through a first input of the atomization chamber; b. introducing a plurality of successive discharges of liquid in the atomization chamber through a second input of the atomization chamber, each discharge including a respective amount of liquid, a duration between two successive discharges being strictly greater than zero, thereby generating, at an output of the atomization chamber, a cleaning flow comprising, successively over time, liquid droplets suspended in gas, the cleaning flow being oriented towards the surface of the medical device.
2 . The cleaning method according to claim 1 , wherein b) comprises providing the plurality of successive discharges periodically, wherein the duration of each discharge is comprised between 0.1 second and 10 seconds, with a frequency comprised between 1 and 1000 discharges per minute.
3 . The cleaning method according to claim 1 , wherein the flow of gas at the output of the atomization chamber, during the contaminant removal phase, is turbulent.
4 . The cleaning method according to claim 1 , wherein, during the contaminant removal phase, a pressure of the gas, at the first input of the atomization chamber, is greater than a pressure of the liquid at the second input of the atomization chamber.
5 . The cleaning method according to claim 4 , wherein, during the contaminant removal phase, a concentration of surfactants in the liquid is lower than 2 mg/L.
6 . The cleaning method according to claim 5 , wherein a concentration of surfactants in the liquid is lower than 200 μg/L.
7 . The cleaning method according to claim 5 , wherein a concentration of surfactants in the liquid is lower than 100 μg/L.
8 . The cleaning method according to claim 1 , wherein the gas is air, dinitrogen or carbon dioxide.
9 . The cleaning method according to claim 1 , further including, prior to the contaminant removal phase, a preliminary phase including providing an initial flow of gas at the output of the atomization chamber, the initial flow of gas at the end of the preliminary phase being turbulent.
10 . The cleaning method according to claim 1 , further including, after the contaminant removal phase, a draining phase, including: outputting, at the output of the atomization chamber, a draining flow of gas; and providing the draining flow of gas to the surface of the medical device to drain residual liquid, the draining flow of gas during the draining phase being turbulent.
11 . The cleaning method according to claim 1 , further including, after the contaminant removal phase, a disinfection phase comprising using a washer-disinfector to disinfect the medical device.
12 . The cleaning method according to claim 1 , wherein the medical device is an endoscope.
13 . A cleaning device for cleaning a surface of a medical device, the cleaning device comprising: a gas input and a liquid input, an atomization chamber including a first input, a second input and an output, a gas line fluidly connected between the gas input and the first input of the atomization chamber, a liquid line fluidly connected between the liquid input and the second input of the atomization chamber, a controller configured to control the gas line and the liquid line so that, during a phase of contaminant removal: (a) the gas line allows circulation of gas from the gas input to the first input of the atomization chamber, in order to inject a continuous flow of gas in the atomization chamber through its first input; and (b) the liquid line allows circulation of liquid from the liquid input to the second input of the atomization chamber, in order to introduce a plurality of successive discharges of liquid in the atomization chamber through its second input, each discharge including a respective amount of liquid, a duration between two successive discharges being strictly greater than zero, thereby generating, at the output of the atomization chamber, a cleaning flow comprising, successively over time, liquid droplets suspended in gas, the cleaning flow being intended to be oriented towards the surface of the medical device.
14 . The cleaning device according to claim 13 , wherein the controller is configured to control the gas line so that the flow of gas at the output of the atomization chamber, during the contaminant removal phase, is turbulent.
15 . The cleaning device according to claim 13 , further including a set of electrodes arranged in a path of the flow of gas, the controller being configured to control a voltage between the electrodes to a level suitable for ionizing the flow of gas.
16 . A cleaning assembly including a cleaning device according to claim 13 , the cleaning assembly further comprising a liquid supply fluidly connected to the liquid input of the cleaning device, and a gas supply fluidly connected to the gas input of the cleaning device.
17 . A washer-disinfector including a cleaning device according to claim 13 .

Description

FIELD The present invention relates to a cleaning method for cleaning a surface of a medical device. The invention applies to cleaning, and more specifically to the removal of contaminant from surfaces of a medical device. BACKGROUND The removal of contaminants from surfaces of a medical device, such as an endoscope, is an essential step in the process of cleaning and disinfecting said device, thus ensuring its reusability and preventing cross-contamination. In the present disclosure, the expression “contaminant” refers to a biofilm and/or to biological soil. To remove contaminants from a surface of a medical device, such as an endoscope, it is known to expose said medical device to one or several solutions, generally in the form of a jet. Said solutions typically include water, a mix of water and surfactants, or an acidic solution. For instance, to clean a channel of an endoscope (and more generally, to clean an inner surface of a tube included in a medical device), a solution of water and surfactants is circulated through said channel to dislodge the contaminant. This is generally done after a step of brushing: the brushing of the endoscope channels with an appropriate brush diameter is mandatory for channels larger than 1.2 mm, while smaller channels are generally not brushed. However, such method is not entirely satisfactory. Indeed, such method relies on the use of brushes, surfactants and other chemicals, which may interact with the medical device and deteriorate it. The use of said chemicals also raises environmental issues, and the brushes produce waste because they are generally single use devices. Moreover, such brushes and chemicals may be costly. Other methods, such as described in JP 2003 145064, use a continuous liquid flow atomized with a continuous gas flow at a stable pressure. However, such methods are not satisfactory. Indeed, in these methods, a more efficient cleaning is only reached with high pressure which may deteriorate the medical device, and these methods consume a large amount of liquid. Therefore, a purpose of the invention is to provide a cleaning method that is effective, while being more environment-friendly and cost-effective than known methods, and having a low risk of damaging the medical device. SUMMARY To this end, the present invention relates to a method of the aforementioned type, including a contaminant removal phase comprising: a. injecting a continuous flow of gas in an atomization chamber, through a first input of the atomization chamber;b. introducing a plurality of successive discharges of liquid in the atomization chamber through a second input of the atomization chamber, each discharge including a respective amount of liquid, a duration between two successive discharges being strictly greater than zero, thereby generating, at an output of the atomization chamber, a cleaning flow comprising, successively over time, liquid droplets suspended in gas, the cleaning flow being oriented towards the surface of the medical device. Indeed, the introduction of a discharge of liquid in a continuous flow of gas leads to an atomization, i.e., a dispersion, of said liquid into droplets. These droplets are carried away by the flow of gas towards the surface to be cleaned. Due to their small size, the energy transfer from the gas to the droplets is efficient, which allows said droplets to easily remove contaminants from said surface, without the need of additional chemicals. This leads the method according to the disclosure to be environment-friendly. Furthermore, by injecting several successive discharges of liquid instead of a continuous liquid stream prevents excessive gas pressure drop that would be detrimental to liquid atomization. Indeed, when a discharge of liquid is injected, it blocks the air flow thereby reducing the speed flow of gas, and droplets are created. When the discharge is stopped, the air flow is not blocked anymore so that the speed flow is increased. Increasing the speed flow also leads to the acceleration of the newly created droplets. By successively reducing and increasing the speed flow, the droplets undergo successive accelerations. When arriving at the cleaning surface, the droplets have been highly accelerated. As a result, good cleaning efficiency can be achieved without a need to increase the pressure of the flow of gas to a level that could damage the medical device: for instance, in the case where lumens of endoscope tubes are cleaned, the pressure of the flow of gas can be maintained within a nominal range provided in the specifications of the endoscope. Moreover, the use of such discharges in combination with a continuous flow of gas results in a lower consumption of liquid, that is to say a cost-effective cleaning method. On the contrary, if a constant flow of droplets is used, as in conventional atomization processes, the pressure of gas tends to drop and the velocity of said droplets is low. This prevents the generation of high shear st