Endoscope is sterilized by?

RUHS, Jaipur, M.Sc Nursing Entrance Exam-2019

Applied Microbiology & Infection control

Hard

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2019

Explanation

Endoscopes are classified as semi-critical devices because they contact mucous membranes, requiring high-level disinfection or sterilization.
These instruments are heat-labile (sensitive to heat) due to their delicate fiber-optic and electronic components, making heat-based methods like autoclaving unsuitable.
2% glutaraldehyde is a widely used chemical sterilant (high-level disinfectant) that effectively kills a broad range of microorganisms without damaging heat-sensitive equipment.
Immersion in 2% glutaraldehyde for a specific duration achieves the necessary level of microbial kill for safe reuse of the endoscope.

Option A: Autoclaving uses high-pressure steam at temperatures that would destroy the delicate fiber-optic and electronic components of an endoscope.
Option B: U.V. radiation has very poor penetration power and is only effective for surface disinfection. It cannot reach and sterilize the internal channels (lumens) of an endoscope.
Option C: Phenol is an intermediate-level disinfectant and is not potent enough for semi-critical instruments like endoscopes, which require high-level disinfection to eliminate all pathogenic microorganisms.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Sterilization and disinfection methods for medical equipment as background academic context rather than a clinical decision trigger.
Proper disinfection of endoscopes is a critical patient safety issue. Failure to do so can lead to the transmission of serious infections like Hepatitis B, Hepatitis C, and multidrug-resistant bacteria between patients.
Nurses play a key role in ensuring that disinfection protocols are followed, including pre-cleaning, leak testing, correct immersion time in the chemical solution, and proper rinsing and storage.
The concentration of glutaraldehyde solutions must be monitored with test strips to ensure it remains effective, as it can be diluted with use.

How to Approach the Question

First, identify the key subject of the question: the 'endoscope'.
Recall or deduce the physical properties of an endoscope: it is a complex instrument with delicate, heat-sensitive components (optics, electronics).
Apply the Spaulding classification: an endoscope contacts mucous membranes, making it a 'semi-critical' device that needs high-level disinfection.
Evaluate each option based on these facts. Eliminate 'Autoclaving' because it uses high heat which would damage the endoscope.
Eliminate 'U.V. Rays' because they cannot penetrate the internal channels of the instrument.
Eliminate '2% phenol' as it is an intermediate-level disinfectant, which is insufficient for a semi-critical device.

Concept Tested & Keywords

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