Systemic absorption of mydriatics in elderly patients can be limited by

RUHS, Jaipur, M.Sc Nursing Entrance Exam-2022

Pharmacology

Easy

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2022

Explanation

Punctal occlusion is a specific technique of applying gentle pressure to the inner canthus of the eye after instilling drops.
This action physically blocks the nasolacrimal duct, which is the primary drainage route for tears and medication into the nasal cavity.
The nasal mucosa is highly vascular, and preventing drainage into this area significantly reduces the amount of drug absorbed into the systemic circulation.
This is especially critical for elderly patients who are more vulnerable to the systemic side effects of mydriatics, such as tachycardia and hypertension.
The technique maximizes the drug's local effect on the eye while minimizing systemic risks.

Option A: A fundus examination is a diagnostic procedure, not an intervention to limit medication absorption. Mydriatics are administered to facilitate this examination.
Option B: While a lower dose reduces the total amount of drug, it may not be therapeutically effective for pupil dilation. More importantly, it doesn't prevent the absorption of the drug that is administered via the nasolacrimal route.
Option C: This term is too general. Punctal occlusion is a specific component of 'proper administration' that directly addresses the question's concern. The most precise answer is the best choice.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacology and Medication Administration: Preventing Systemic Absorption of Ophthalmic Drugs as background academic context rather than a clinical decision trigger.
Patient safety is paramount, especially in vulnerable populations like the elderly. Preventing systemic side effects from topical medications is a key nursing responsibility.
Nurses must not only perform punctal occlusion correctly but also educate patients and their caregivers on how to do it at home to ensure continued safety and medication efficacy.
What if the patient has arthritis and cannot apply pressure themselves? The nurse should teach a family member or caregiver the technique and verify their ability to perform it correctly. If no one is available, other strategies, like using a commercial punctal occlusion device, might be explored with the ophthalmologist.

How to Approach the Question

First, analyze the question to identify the core problem: how to limit the systemic (body-wide) effects of a topical eye medication (mydriatics) in a high-risk group (elderly).
Evaluate each option for its mechanism of action. Ask yourself, 'How does this action specifically prevent the drug from entering the bloodstream?'
Recognize that 'systemic absorption' of eye drops primarily occurs via the nasolacrimal duct into the nasal mucosa.
Compare the options. 'Fundus examination' is the reason for the drug, not a preventative measure. 'Lesser concentration' reduces the dose but not the absorption pathway. 'Proper administration' is vague.
'Punctal occlusion' describes a specific physical action that directly blocks the absorption pathway. This makes it the most direct and effective intervention.
Select the option that describes the most specific and effective mechanism to solve the stated problem.

Concept Tested & Keywords

Concept Tested: Pharmacology and Medication Administration: Preventing Systemic Absorption of Ophthalmic Drugs
Stem keywords: systemic absorption, mydriatics, elderly patients
Lead-in keywords: limited by
Clinical cues: Age/sex group narrows the expected diagnosis, intervention, or normal reference range.
Negative lead-in flag: false