Intranasal nitroglycerin and intraocular pressure during general anesthesia.

Area of Science:

• Anesthesiology
• Ophthalmology
• Pharmacology

Background:

• Intraocular pressure (IOP) management is critical during anesthesia.
• Succinylcholine and tracheal intubation can cause significant IOP elevation.
• Nitroglycerin (NTG) is a vasodilator with potential effects on IOP.

Purpose of the Study:

• To investigate the effect of intranasal nitroglycerin (NTG) on intraocular pressure (IOP) in anesthetized patients.
• To determine if NTG pretreatment can mitigate IOP increases associated with anesthetic induction and tracheal intubation.

Main Methods:

• Study I: 12 healthy adults received intranasal NTG during anesthesia; IOP, arterial blood pressure, and central venous pressure were monitored.
• Study II: 30 patients received either intranasal NTG or saline double-blindly before anesthesia induction with thiopental and succinylcholine.
• IOP was measured before induction, after succinylcholine, and after tracheal intubation in both groups.

Main Results:

• Intranasal NTG significantly decreased IOP, arterial blood pressure, and central venous pressure in Study I.
• In Study II, saline group showed significant IOP increase after succinylcholine and intubation.
• NTG group exhibited significantly less IOP increase after succinylcholine and intubation compared to the saline group.

Conclusions:

• Intranasal administration of nitroglycerin effectively decreases intraocular pressure in anesthetized patients.
• NTG pretreatment prevents significant IOP elevation during tracheal intubation, even when using succinylcholine.
• Intranasal NTG is a viable option for managing IOP during anesthesia, facilitating intubation procedures.