Factors associated with cleaning quality of reusable medical devices at a single center in China

Abstract

Background

Improper cleaning is one of the main causes of sub-optimal levels of sterilization, and also a risk factor in terms of nosocomial infections. We aimed to investigate the factors associated with the cleaning quality of the reusable medical devices and prescribe improvement measures for ensuring the safe use of the devices and for iatrogenic infection control.

Methods

An expert consultation was conducted to identify the factors associated with the cleaning quality of reusable medical devices. A self-designed quality inspection form for reusable medical device cleaning was used to collect the data concerning the factors associated with the cleaning quality of the reusable medical devices cleaned at our hospital's central sterile supply department (CSSD) during January to June 2022. We also investigated the cleaning personnel's perceptions and knowledge of medical devices cleaning by means of a self-designed questionnaire.

Results

Statistically significant differences (P < 0.05) were identified among incorrect cleaning procedures, improper cleaning methods, non-standard pre-treatment, wrong perceptions or lack of knowledge of medical device cleaning, and complex device structure. Correct cleaning procedures (odds ratio (OR) = 0.216, 95 % confidential interval (CI): 0.170–0.275), choice of cleaning method (ultrasonic cleaning OR = 3.995, 95 % CI: 2.937–5.434; spray cleaning OR = 0.893, 95 % CI: 0.735–1.085), standard pre-treatment (OR = 1.470, 95 % CI: 1.191–1.815), complex device structure (OR = 1.534, 95 % CI: 1.247–1.888) and cleaning personnel's correct perceptions of medical device cleaning (OR = 0.530, 95 % CI: 0.436–0.645) were the independent factors associated with the cleaning quality.

Conclusions

The quality of reusable medical device cleaning should be improved by: adherence to standard cleaning procedures, choosing the correct cleaning method and pre-treatment, improving cleaning personnel's knowledge and perceptions of medical device cleaning, and disassembling the medical devices with complex structures so as to reduce the quality defects of medical device cleaning.

1. Introduction

The central sterile supply department (CSSD) is responsible for the cleaning and disinfection of reusable medical devices and for the supply of sterile items in the hospital. It aims to ensure the successful sterilization and elimination of nosocomial infections [1,2]. The surfaces of these reusable devices come into contact with the patients’ blood, excreta, human tissue secretions and other bodily fluids. If the used medical devices are not cleaned thoroughly, the organic residues can form a biofilm [3,4] and microorganisms and viruses may also remain on the surface of the devices. The structure of the shafts, articulation joints or grooves of some reusable medical devices can impair decontamination by increasing the difficulty of cleaning and disinfection [5]. Thorough cleaning is the key to successful disinfection and sterilization [6].

Dong et al. [7] reported that the pass rate of reusable medical device cleaning, determined using adenosine triphosphate (ATP) bioluminescence detection, ranges between 80.1 % and 94.6 %. In the studies of Dong et al. [7], the desktop ATP fluorescence measuring device manufactured by Ruhof Corporation, a company located in New York, United States was used, in which the amount of ATP ≤45 relative light units (RLUs) was set as a “pass” in the quality of cleaning. The cleaning quality of a total of 240 pieces of commonly used surgical devices was tested on site using the single-blind method within the same time period after cleaning by refining the cleaning process. Rigid endoscopes, ophthalmological devices and powered tools were selected, with 80 pieces each used. The number of devices received a “pass” in the cleaning quality test using ATP fluorescence measurement, before and after process refinement, was 194 and 227 respectively, coming to the conclusion that the pass rate of reusable medical device cleaning ranges between 80.1 % and 94.6 %.

Gao et al. [8] reported that the success rate of autoclave sterilization following improper cleaning is 70%–95 %. In the studies of Gao et al. [8], cleaned items were sampled after autoclave sterilization to detect microbial residue, including pathogenic and non-pathogenic microorganisms and bacterial spores. If these microorganisms or bacterial spores were not detected, the items were considered to have passed the sterilization test. Improper cleaning is one of the main causes of unstable pass rates of sterile items in sterilization, and also a risk factor in terms of nosocomial infections [9,10]. Therefore, cleaning is an important step in processing reusable medical devices, and cleaning quality is one of the key factors that directly affect the quality of sterilization. It is very important to explore the reasons that affect the cleaning quality of reusable medical devices in order to continuously improve the cleaning quality. In this study, we investigated the factors associated with the cleaning quality of the reusable medical devices. We also prescribe improvement measures for ensuring the safe use of the reusable medical devices and for iatrogenic infection control.

2. Materials and methods

2.2. Ethics approval

This study was conducted in accordance with the Declaration of Helsinki. All research methods were carried out in accordance with the relevant guidelines and regulations. This study was approved by the Medical Ethics Committee of West China Second University Hospital, Sichuan University [2023 Medical Scientific Research for Ethical Approval No. (002)].

2.2. Study setting

A total of 40,990 reusable medical devices were randomly sampled by our hospital's CSSD quality controllers from all reusable medical devices cleaned at our CSSD during January to June 2022. Of them, 512 reusable medical devices with cleaning failures were identified. Common devices (common surgical scalpel, surgical scissors, surgical forceps, hemostats, needle holders, tissue forceps and retractors), endoscopic devices (separating pliers, nondestructive forceps, pneumoperitoneum needles, grasping forceps, electrosurgical hooks, da Vinci robotic surgical instruments and rigid endoscopes), and precision devices (ophthalmological, cardiovascular, oral instruments and those used for nasal and facial plastic surgeries), were included in this study. Medical devices rented from medical device manufactures for surgical procedures, flexible bronchoscopes, gastrointestinal flexible endoscopes, urologic flexible endoscopes, or powered instruments, were excluded from this study. Our hospital has 45 operating rooms and an annual surgical volume of around 60,000 cases. Our CSSD processes more than 8 million reusable medical devices per year.

2.3. Study tools

2.3.1. Identify the factors associated with the cleaning quality of reusable medical devices

After consulting relevant literatures [11,12], Decontamination and Reprocessing of Medical Devices for Health-care Facilities released by the World Health Organization [13] and Central Sterile Supply Department (CSSD) - Part 2: Standard for Operating Procedure of Cleaning, Disinfection and Sterilization released by the National Health Commission of China [14], we listed following possible factors associated with the cleaning quality of reusable medical devices using root cause analysis and brainstorming:

• (1)Manpower. This refers to insufficient cleaning personnel, cleaning personnel's lack of awareness regarding the significance of medical device cleaning, inadequate training, low education attainment and lack of responsibility, and insufficient supervision of management personnel.
• (2)Machine. This refers to insufficient cleaning equipment, cleaning equipment failures, and the water pressure and temperature of the cleaning equipment not meeting the required criteria.
• (3)Material. This refers to inappropriately selected cleaning tools or cleaning agents, wrong quantity of devices, complex device structure, and cleaning agents or rust remover remaining on the surface of the devices after cleaning.
• (4)Methods. This refers to improper classification methods for devices, no cleaning flowchart for special devices, manipulation not followed cleaning procedures, no standard pre-treatment, inappropriate cleaning methods, inappropriate disassembly methods and improper machine cleaning loading.
• (5)Environment. This refers to lighting, temperature and humidity not meeting the required criteria, an insufficient place to work, a noisy environment, and secondary pollution.

We wrote a consultation letter concerning the factors associated with the cleaning quality of reusable medical devices based on the above-mentioned factors. A total of 6 experts from different CSSDs of different hospitals in different provinces were invited by email to participate in the consultation concerning the factors associated with the cleaning quality of reusable medical devices. All of the experts had at least 10 years of work experience in CSSD, possessed rich experience in nursing management, and were members of their respective provincial-level sterile supply committees. Of them, 1 was a chief nurse, 2 were co-chief nurses, and 3 were supervising nurses. Influential factors were revised through a consensus of experts. The following influential factors were identified: (1) Whether the reusable medical device was sorted for cleaning; (2) Whether correct cleaning procedures were used; (3)Which method of cleaning was used; (4) Whether suitable cleaning tools were used; (5) Whether pre-treatment was implemented; (6) Whether appropriate cleaning agents were used; (7) Whether the cleaning personnel possessed sufficient knowledge of medical device cleaning; (8) Whether the device structure was complex; (9) Whether secondary pollution had occurred.

2.3.2. Design a quality inspection form for medical device cleaning

We designed a cleaning quality inspection form (Supplementary Fig. 1) to record data concerning: date, time, name of the reusable medical device, quantity of cleaning defects, type of device, location of cleaning defects, whether pre-treatment was performed, cleaning method, and what factor was associated with the cleaning defect. The form was filled out by quick response code scan. The inspectors working in the inspection area strictly inspected the cleaning quality of all devices included in this study, made judgments based on the prescribed evaluation criteria, and accurately recorded information of the reusable medical devices on the inspection form in a timely manner.

2.3.3. Evaluation criteria

2.3.3.1. Cleaning quality of reusable medical devices

According to the Central Sterile Supply Department (CSSD) - Part 2: Standard for Operating Procedure of Cleaning, Disinfection and Sterilization released by the National Health Commission of China [14] and relevant literatures [15,16], the inspectors working in the inspection area should conduct a visual inspection or use a light magnifier to check the cleaning quality of each device. A cleaning failure occurs whenever water stains, blood, dirt, or rust appear or remain on the surface, articulation joints, grooves or lumens of the device.

2.3.3.2. Cleaning personnel's perceptions and understanding of medical device cleaning

We investigated the CSSD cleaning personnel's perceptions and understanding of medical device cleaning by means of a self-designed questionnaire. The questionnaire contains 10 questions concerning: the name of the medical device, device disassembly methods, device structure processing, cleaning steps, cleaning tools, and precautions for cleaning. According to the hospital's regulations on cleaning staff assessment, the maximum score of the questionnaire was 100. A respondent whose score was 85 or above was considered to possess sufficient knowledge and correct perceptions.

2.3.3.3. Cleaning procedures

Cleaning personnel should strictly follow the cleaning procedures: flush - wash - rinse - terminal rinse.

2.3.3.4. Choice of cleaning tools

Lumen cleaning brushes that are suitable for the length and diameter of the lumen should be used for lumen devices. Micro-fiber cleaning cloth should be used to clean the surface of the precision devices. The choice of soft and hard brushes was subject to what material the device was made from. Abrasive cleaning tools should not be used.

2.3.3.5. Choice of cleaning agents

The cleaning agents from the same production batch that were produced by the same manufacturer were used for cleaning in our study.

2.4. Data collection

The inspection form for cleaning quality of reusable medical devices was used for collecting the data concerning cleaning failures. Information from the research subjects was obtained from the information traceability system. Data entry was double checked by two researchers. Each cleaning step of each device was supervised by the head nurse of the research team or the quality controller, who possessed more than 10 years of work experience. Training on relevant knowledge, procedures and evaluation criteria was provided for cleaning personnel, packaging personnel, and quality controllers who participated in this study. This was done to achieve consistency and accuracy in the study, and to strictly control the deviation of this study.

2.5. Statistical methods

Statistical Product and Service Solutions version 25.0 was used for data analysis. The enumeration data are presented as [n (%)] and were generated using the Chi-square (χ²) test. The variables with differences in the comparison between groups are considered as independent variables. Whether cleaning quality receives a “pass” was consider as the dependent variable and analyzed using multivariate logistic regression. Statistically significant differences were identified by α = 0.05 and P < 0.05.

3. Results

3.1. Cleaning failures

Of the 40,990 samples, 512 (1.25 %) were considered as ‘cleaning failure’. The number of failure cases in common devices, endoscopic devices and precision devices was 163 (31.8 %), 253 (49.4 %) and 96 (18.7 %), respectively. Details of the incidences of cleaning failures in different devices are presented in Fig. 1, Fig. 2, Fig. 3.

Fig. 1.

Incidence of cleaning failures in common devices.

Fig. 2.

Incidence of cleaning failures in endoscopic devices.

Fig. 3.

Incidence of cleaning failures in precision devices.

3.2. Mono-factor analysis

Of the 40,990 samples, 512 (1.25 %) were considered as ‘cleaning failure’ and 40,478 (98.75 %) were awarded a ‘pass’ in cleaning. Statistically significant differences (P < 0.05) were identified among whether the device was sorted for cleaning, whether correct cleaning procedures were used, which method of cleaning was used, whether suitable cleaning tools were used, whether pre-treatment was implemented, whether the cleaning personnel possessed sufficient knowledge of medical device cleaning, and the complexity of the instrument structure. No statistically significant differences (P > 0.05) were identified among whether suitable cleaning agents were used and whether secondary pollution had occurred (Table 1).

Table 1.

Mono-factor analysis of the factors associated with the cleaning quality of reusable medical devices.

Variables	Grouping	Cleaning quality		χ2	P
		Failure	Pass
Was the device sorted for cleaning?	Yes	278	24271
	No	234	16207	6.753	0.009
Were correct cleaning procedures used?	Yes	92	23848
	No	420	16630	348.953	<0.001
Which method of cleaning was used?	Pulsating vacuum	49	14501
	Ultrasonic cleaning	184	12446
	Spray cleaning	279	13531	169.185	<0.001
Were suitable cleaning tools used?	Yes	230	16117
	No	282	24361	5.496	0.019
Was pre-treatment implemented?	Yes	121	7288
	No	391	33190	10.185	0.001
Were suitable cleaning agents used?	Yes	383	29092
	No	129	11386	2.154	0.142
Did the cleaning personnel possess sufficient knowledge of surgical instrument cleaning?	Yes	157	23295
	No	355	17183	149.297	<0.001
Was the instrument structure complex?	Yes	383	35829
	No	129	4649	92.288	<0.001
Had secondary pollution occurred?	Yes	342	25858
	No	170	14629	1.863	0.172

3.3. Multivariate logistic regression analysis

The factors (whether the device was sorted for cleaning, whether correct cleaning procedures were used, which method of cleaning was used, whether suitable cleaning tools were used, whether pre-treatment was implemented, whether the cleaning personnel possessed sufficient knowledge of medical device cleaning, and the complexity of the device structure) with statistically significant differences in the mono-factor analysis, were considered to be the independent variables. The factor associated with cleaning quality was considered to be the dependent variable. Further details of the variables are presented in Table 2. The incidence of failures in reusable medical devices with correct cleaning procedures (odds ratio (OR) = 0.216, 95 % confidential interval (CI): 0.170–0.275) was 0.216 times more than with incorrect cleaning procedures. The incidence of failures in reusable medical devices using ultrasonic cleaning (OR = 3.995, 95 % CI: 2.937–5.434) was 3.995 times more than using pulsating vacuum cleaning. The incidence of failures in reusable medical devices without pre-treatment (OR = 1.470, 95 % CI: 1.191–1.815) was 1.47 times more than with pre-treatment. The incidence of failures in reusable medical devices cleaned by the personnel with sufficient knowledge and perceptions of medical device cleaning (OR = 0.530, 95 % CI:0.436–0.645) was 0.53 times more than cleaned by the personnel with insufficient knowledge and perceptions of medical device cleaning. The incidence of failures in devices with a complex structure (OR = 1.534; 95 % CI: 1.247–1.888) was 1.534 times more than without a complex structure (Table 3).

Table 2.

Variable assignment.

Factors	Assignment description
Was the device sorted for cleaning?	1 = Yes, 2 = No (Control group)
Were correct cleaning procedures used?	1 = Yes, 2 = No (Control group)
Which method of cleaning was used?	1 = Pulsating vacuum (Control group), 2 = Ultrasonic cleaning, 3 = Mechanical cleaning
Were suitable cleaning tools used?	1 = Yes, 2 = No (Control group)
Was pre-treatment implemented?	1 = Yes, 2 = No (Control group)
Did the cleaning personnel possess sufficient knowledge of surgical instrument cleaning?	1 = Yes, 2 = No (Control group)
Was the device structure complex?	1 = Yes, 2 = No (Control group)

Table 3.

Multivariate logistic regression analysis of the factors associated with the cleaning quality of reusable medical devices.

Variables	B	Standard error	Waldχ2	P	Odds ratio	95 % confidence interval
The device was sorted for cleaning	0.214	0.162	1.745	0.187	1.239	0.902–1.702
Correct cleaning procedures were used	−1.531	0.122	156.943	<0.001	0.216	0.170–0.275
Ultrasonic cleaning	1.385	0.157	77.912	<0.001	3.995	2.937–5.434
Spray cleaning	−0.113	0.099	1.295	0.255	0.893	0.735–1.085
Pre-treatment was used?	0.385	0.107	12.848	<0.001	1.470	1.191–1.815
The cleaning personnel possessed sufficient knowledge of surgical instrument cleaning	−0.634	0.100	40.150	<0.001	0.530	0.436–0.645
The device structure complex?	0.428	0.106	16.334	<0.001	1.534	1.247–1.888
Constant

3.4. Effects of factors associated with the cleaning quality of reusable medical devices

The effects of factors associated with the cleaning quality of reusable medical devices, that are beneficial to or bad for cleaning quality, are presented in Table 4.

Table 4.

Effects of factors associated with the cleaning quality of reusable medical devices.

Influencing factors	Beneficial to cleaning quality	Bad for cleaning quality
Cleaning procedures	Correct cleaning procedures	Incorrect cleaning procedures
Cleaning methods	Pulsating vacuum cleaning	Ultrasonic cleaning
Pre-treatment	Correct pre-treatment	Incorrect pre-treatment
Cleaning personnel's knowledge and perceptions of medical device cleaning	Sufficient knowledge and perceptions	Insufficient knowledge and perceptions
Device structure	Uncomplex structure	Complex structure

4. Discussion

Due to ongoing developments in medical technology, more and more medical devices are being used in clinical practice, and the diversity of medical devices continues to increase. Overall, these trends have had positive effects on clinical treatment. However, the disinfection, sterilization and maintenance of medical devices has become more complicated, significantly affecting the CSSD work. Properly cleaned, disinfected, and sterilized medical devices provide a better protective effect against nosocomial infections [17]. The results of Li et al. [18] have shown that cleaning quality problems are related to multiple factors, such as non-standard pre-treatment, poor adherence to correct cleaning procedures, cleaning agent residues, and short soaking time of instruments. Our study has found that incorrect cleaning procedures, improper cleaning methods, non-standard pre-treatment, wrong perceptions or lack of knowledge of medical device cleaning, and complex device structure, were the main factors leading to cleaning failures. These shortcomings should be addressed in order to achieve controllability.

4.1. Influencing factors

• (1)Incorrect cleaning procedures. Cleaning personnel might not always closely follow the standard cleaning procedures. They might ignore some cleaning steps to save time and improve cleaning speed, resulting in poor cleaning effect. This was found to be the main reason for cleaning failures occurred during urgent device processing in this study.
• (2)Choice of cleaning methods. In this study, no statistically significant differences in cleaning quality were found between the pulsating vacuum and spray cleaning, this may be explained by the wide variety of types of medical devices used in our hospital. The lumen devices, precision devices and common gynecologic devices are used widely throughout our hospital. The pulsating vacuum and spray cleaning methods should be used for different types of devices. Improper cleaning methods can lead to inconspicuous results in cleaning quality comparison.
• (3)Non-standard pre-treatment. The results of Huang et al. [19] have shown that the implementation rate of instrument moistening is only 57.24 %. If improper pre-treatment is implemented, a biofilm can form on the surface of the device within 2 h after the contaminants dry out [20]. When the biofilm is formed, it can be removed with a certain concentration of peracetic acid, alkali and enzyme cleaning agent and glutaraldehyde cleaning agent [21]. The results of our study have shown that non-standard/lack of pre-treatment was the significant factor affecting the cleaning quality of reusable medical devices. In clinical work, most medical staff might not always be able to pre-process the reusable medical devices in conformity with relevant guidelines due to heavy workload and multiple medical treatments, causing blood and other bodily fluids on the surfaces of the devices to dry [22]. During cleaning, using scouring pads or hard brushes to remove the dry and solidified contaminants can cause scratches on the surface of the device and make the device prone to rust following its repeated use, leading to imperfect cleaning later on. Some clinical department staff in our hospital do pre-process all the reusable medical devices in conformity with relevant guidelines, but most clinical department staff in our hospital have at some stage neglected full device pre-treatment or were ignorant of certain pre-treatment guidelines.
• (4)The cleaning personnel's perceptions and knowledge of medical device cleaning.

Subjective factors such as the cleaning personnel's decision for each device, their educational attainments, attitudes towards cleaning, and the job specificity may affect the manipulation actions undertaken during cleaning. For example, poor and inadequate education and lack of knowledge of medical device cleaning can lead to an unclear understanding of job responsibilities, improper preparation of cleaning agent, insufficient water pressure and insufficient soaking time. Cleaning actions based on subjective consciousness does not guarantee satisfactory cleaning quality [23]. Some cleaning personnel in our hospital possessed junior or senior high school diplomas, but their relevant employment experience varies widely, a dissimilarity which can also impact the cleaning quality.

• (5)Complex device structure. Contaminants are more likely to remain in the medical devices with special or complex structure, as well as in narrow lumen devices, significantly affecting the cleaning and sterilization effect. In this study, we found that 253 out of 512 failures occurred in the endoscopic devices. The endoscopic devices, such as electrocoagulation forceps, cup-shaped uterus lifting device, endoscope irrigator, have a complex structure, long manipulator arms, grooves, and multiple components, and so tissues and blood residues are more likely to remain in the lumens, grooves and articulation joints thereof. Cleaning failures were more likely to occur in the endoscopic devices than in the common devices.

4.2. Recommended prevention strategies

• (1)Medical devices shall be cleaned in conformity with the standard cleaning procedures. The standard cleaning procedures and relevant guidelines shall be communicated clearly to the CSSD personnel by means of a cleaning workflow chart. A three-level quality control inspectorate consisting of a head nurse, quality controllers and inspectors shall be established to supervise the implementation of the established cleaning procedures. The head nurse shall conduct a random quality inspection every week, the quality controllers shall conduct quality monitoring every day, and the head of the cleaning team shall be responsible for supervising the implementation of the system, responsibilities, workflow and various management regulations so that the cleaning personnel can clean the instruments in conformity with the workflow process, ‘flush - wash - rinse - terminal rinse’. For devices that require special cleaning procedures, such as da Vinci robotic instruments, endoscopes, and precision devices, a specific standard operating procedure diagram for cleaning shall be created (Fig. 4) and pasted to the corresponding cleaning tables so that the cleaning personnel can consult it at any time during cleaning. In a further effort to reduce the risk of neglect of cleaning steps during urgent device processing, it is recommended to purchase devices as much as possible within a reasonable cost control threshold to ensure adequate supply of devices, thereby avoiding the neglect of the cleaning steps due to insufficient devices.
• (2)Use different cleaning methods for different types of devices. For devices such as those with power systems and precision ophthalmic devices that require ultrasonic cleaning (for which pulsating vacuum cleaning is not suitable), it is recommended to manually wash off the visible contaminants and then perform ultrasonic cleaning to make up for the deficiency of ultrasonic cleaning (not implemented with running water). For complex lumen devices, the pulsating vacuum cleaning is more effective [24].
• (3)Standard pre-treatment. According to the relevant guidelines, the instruments should be wiped off contaminants and sent to the CSSD for cleaning within 30min after use; otherwise, the instruments should be kept moist [25] through evenly or targeted spraying with moisturizing agent or fully immersed in the moisturizing agent. The CSSD shall (i) provide training on instrument moistening and develop standard operating procedures for moistening of instruments in the clinical departments, (ii) arrange specific personnel to provide guidance on instrument moistening, and (iii) investigate the moistening effect after the instruments are collected from the clinical departments. More training on instrument moistening shall be provided for clinical departments until such time when moistening is properly implemented throughout the clinical departments.
• (4)Improve cleaning personnel's perceptions and knowledge of medical device cleaning. A cleaning ‘mind map’ diagram shall be distributed among the cleaning personnel to test their knowledge of cleaning procedures and help them upskill. Theoretical knowledge, manipulation, integrative competence and personal traits are widely used evaluation criteria for CSSD staff [26]. It is recommend to provide training on theoretical knowledge and manipulative skills in cleaning, such as the concept, workflow and methods of cleaning, medical device sorting methods, cleaning procedures for special instruments, choice of cleaning equipment, cleaning tools and cleaning agents, and operating procedures applied to cleaning equipment. Training by demonstration, drills and watching videos are recommended to improve the cleaning personnel's quality and safety awareness and cleaning skills. An assessment shall be carried out after each training session. Performance rewards shall be given to the cleaning personnel with fewer errors in an effort to stimulate enthusiasm in their work. Further, the designation of different technical and general occupations is recommended. Technical posts can be divided into endoscopic device cleaning, powered device cleaning, and precision device cleaning. The job responsibilities of each post shall be identified, and communicated clearly to each cleaning operative. The cleaning personnel shall be familiar with the key points of disassembly and cleaning of the devices in their respective posts so as to improve the quality of device cleaning.
• (5)Medical devices with complex structure shall be cleaned after disassembly. It is recommended to formulate the disassembly workflow chart for the devices with complex structure, mark the key parts, and paste each chart in the workplace so that the cleaning personnel can consult it at any time during cleaning. The shafts, screw nuts, core, screws and manipulation arms of the device with complex structure should be disassembled and cleaned separately following the manual cleaning procedures. If the components cannot be disassembled, the device should be in an open (unlocked) position. Ultrasonic or pulsating vacuum cleaning should then be applied.

Fig. 4.

Standard operating procedure for da Vinci robotic endoscope cleaning.

5. Conclusions

The quality of reusable medical device cleaning should be improved by: adherence to standard cleaning procedures; choosing the correct cleaning method and pre-treatment; improving cleaning personnel's knowledge and perceptions of medical device cleaning; and disassembling the medical devices with complex structures so as to reduce the quality defects of medical device cleaning. In this study, the selection of cleaning methods is limited. Subsequent studies can be conducted on new cleaning methods, such as spray cleaning and reduced pressure boiling cleaning, to examine the cleaning effect. Our study relied on visual inspection and a light magnifier to determine cleaning quality and was not based on explicit values. Future research may consider using additional cleaning quality measurement methods to evaluate cleaning quality, such as measurement of protein residues and ATP fluorescence.

Ethics statement

This study was reviewed and approved by the Medical Ethics Committee of West China Second University Hospital, Sichuan University, with the approval number: 2023 Medical Scientific Research for Ethical Approval No. (002). All participants provided informed consent to participate in the study.

Funding

None.

Data availability statement

The data are not publicly available due to their containing information that could compromise the privacy of research participants.

CRediT authorship contribution statement

Juanli Huang: Writing - original draft, Methodology, Investigation, Conceptualization. Liangying Yi: Writing - review & editing. Yanhua Chen: Methodology, Formal analysis, Conceptualization. Juan Hu: Writing - review & editing.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Appendix A. Supplementary data

The following are the supplementary data to this article:

Fig. S1.

Inspection form for cleaning quality of reusable medical devices.

Fig. S2.

Technological route of the study.