Question

A 5 year old child is scheduled for strabismus (squint) correction. Induction of anesthesia is uneventful. After conjunctival incision, as the surgeon grasps the medial rectus, the anesthesiologist looks at the cardiac monitor. Why do you think he did that?

• A. He wanted to check the depth of anaesthesia.
• B. He wanted to be sure that the blood pressure did not fall.
• C. He wanted to see if there was an oculocardiac reflex.
• D. He wanted to make sure there were no ventricular dysrhythmias which normally accompany incision.

Hint:

Traction on the medial rectus can trigger the oculocardiac (Aschner) reflex, causing sudden bradycardia.

Answer 1

The Correct Option is C

This question checks whether you know what happens when the eye muscles are pulled during strabismus surgery, a classic trigger for a specific heart reflex.

1. Check the depth of anaesthesia: Depth is judged from several signs together, movement, blood pressure trend, and pupil size, not by watching the monitor at the exact moment a muscle is grasped. This does not fit the timing described.
2. Make sure blood pressure did not fall: A generic blood pressure drop is not specifically linked to grasping an eye muscle. It does not explain why the anesthesiologist reacted right at that moment.
3. See if there was an oculocardiac reflex: Pulling the medial rectus is the classic trigger for this vagal reflex, which can cause the heart rate to drop suddenly. Watching the monitor exactly when the muscle is grasped fits this perfectly.
4. Watch for ventricular dysrhythmias from the incision: A simple conjunctival incision does not normally trigger ventricular arrhythmias. This option invents a link that does not exist in practice.

The oculocardiac reflex is well documented in eye muscle surgery, especially in children, and can appear within seconds of traction, which matches the scenario exactly.

Let's summarize:

• Traction on extraocular muscles, most strongly the medial rectus, sends a signal via the trigeminal nerve that triggers a vagal slowing of the heart.
• This oculocardiac reflex is common in pediatric strabismus surgery and needs quick recognition so traction can be released.

So the anesthesiologist checked the monitor to look for signs of the oculocardiac reflex.