Laparoscopic Lens Defogging Using Anti-fog Solution, waRm Saline, and Chlorhexidine Solution

Study Overview
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Brief Summary
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The aim of this study is to compare three popular methods of minimizing or reducing laparoscopic lens fogging (LLF) by heating lens using warm saline, applying anti-fog agent to lens, and rubbing lens with chlorhexidine in laparoscopic gynecologic surgery.

Detailed Description
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The physiology behind laparoscopic lens fogging (LLF) is well understood based on meticulous experiments outlining the role of temperature and humidity. Despite many efforts, including uses of warm saline, various anti-fog agents, chlorhexidine, betadine, and rubbing the lens on serosal surfaces, to reduce LLF, there remains no consensus as to which method is superior to prevent LLF. Furthermore, most previous studies were experimental trials conducted in a simulation model or a non-human in vivo model or an expert's commentary based on their clinical experiences , and there was no randomized controlled trial focusing LLF in human model. Therefore, this randomized trial aimed to compare three popular methods of minimizing or reducing LLF by heating lens using warm saline, applying anti-fog agent to lens, and rubbing lens with chlorhexidine in laparoscopic gynecologic surgery.

Official Title
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Randomized Comparison of Laparoscopic LEns Defogging Using Anti-fog Solution, waRm Saline, and Chlorhexidine Solution (CLEAR)

Conditions
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Gynecologic Disease

Intervention / Treatment
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* Device: Warm saline
* Device: anti-fog agent
* Device: chlorhexidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 18 and 65 years American Society of Anesthesiologists physical status (ASAPS) classification I-II the absence of pregnancy at the time of surgery Exclusion Criteria: allergy to chlorhexidine or anti-fog solution anticipating cases of abrupt change in intra-abdominal humidity such as hemoperitoneum and profuse ascites extremely short or long operative time (<20 min or > 180 min) affecting the frequency of LLF unavailability of the surgical recording equipment for laparoscopic procedure.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Warm saline group<br>In subjects allocated to the warm saline group, a thermos flask, which was filled with heated sterile water, was used. A 1000 ml bottle of sterile water was heated to 60 ˚C in a stove for an hour at minimum. Just before introducing into the abdominal cavity, the laparoscope was placed into the thermos flask for 30 seconds at minimum . After each incidence of laparoscopic lens fogging (LLF), the scope was briefly inserted into the thermos flask about 10 seconds, and was then wrapped gauze around the lens before abdominal reinsertion. | Device: Warm saline<br>* In subjects allocated to the warm saline group, a thermos flask, which was filled with heated sterile water, was used. A 1000 ml bottle of sterile water was heated to 60 ˚C in a stove for an hour at minimum. Just before introducing into the abdominal cavity, the laparoscope was placed into the thermos flask for 30 seconds at minimum . After each incidence of laparoscopic lens fogging (LLF), the scope was briefly inserted into the thermos flask about 10 seconds, and was then wrapped gauze around the lens before abdominal reinsertion.<br>|
| Experimental: anti-fog agent group<br>In the anti-fog agent group, Ultra-Stop TM (Sigmaphrarm, Vienna, Austria), which is a commercial anti-fogging solution containing alcohol, surfactant, and water for medical optical devices, was used. Wiping the lens with gauze soaked in Ultra-Stop TM and allowing the surfactant to act for 5 seconds, the laparoscope was introduced into the abdominal cavity. After each laparoscopic lens fogging (LLF), the scope was removed from the abdomen and cleaned using the same corresponding method. | Device: anti-fog agent<br>* In the anti-fog agent group, Ultra-Stop TM (Sigmaphrarm, Vienna, Austria), which is a commercial anti-fogging solution containing alcohol, surfactant, and water for medical optical devices, was used. Wiping the lens with gauze soaked in Ultra-Stop TM and allowing the surfactant to act for 5 seconds, the laparoscope was introduced into the abdominal cavity. After each laparoscopic lens fogging (LLF), the scope was removed from the abdomen and cleaned using the same corresponding method.<br>|
| Experimental: chlorhexidine group<br>In the chlorhexidine group, the lens was wiped with gauze soaked in 4% chlorhexidine detergent solution (Firson, Cheonan, Korea) for 5 seconds before introducing into the abdominal cavity, and chlorhexidine was reapplied on the lens at the occurrence of laparoscopic lens fogging (LLF). | Device: chlorhexidine<br>* In the chlorhexidine group, the lens was wiped with gauze soaked in 4% chlorhexidine detergent solution (Firson, Cheonan, Korea) for 5 seconds before introducing into the abdominal cavity, and chlorhexidine was reapplied on the lens at the occurrence of laparoscopic lens fogging (LLF).<br>|
| No Intervention: control group<br>In the control group, the lens was not wiped gauze or applied any solution before use of the laparoscope. When occurred the event of each laparoscopic lens fogging (LLF) that splatter of irrigation fluid, blood, and body fluids affected visual clearance, the laparoscopic lens was manually rubbed with clean gauze by a scrub nurse. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the severity of LLF during the first 3-min operation | The severity of LLF was rated on a scale of 0 (the clearest) to 10 (the foggiest). | At the time of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the severity of LLF occurred during the remaining operative time except the first 3-min | The severity of LLF was rated on a scale of 0 (the clearest) to 10 (the foggiest). | At the time of surgery | 
| the number of lens cleansing | We will assess the number of lens cleansing at the time of surgery. | At the time of surgery | 
| total time to spend for lens cleaning | We will assess the total time to spend for lens cleansing at the time of surgery. | At the time of surgery |