Effects of remifentanil and fentanyl on intraocular pressure during the maintenance and recovery of anaesthesia in patients undergoing non-ophthalmic surgery

Attenuation of increased intraocular pressure with propofol anesthesia: A systematic review with meta-analysis and trial sequential analysis

Attenuation of an increase in intraocular pressure (IOP) is crucial to preventing devastating postoperative visual loss following surgery. IOP is affected by several factors, including the physiologic alteration due to pneumoperitoneum and patient positioning and differences in anesthetic regimens. This study aimed to investigate the effects of propofol-based total intravenous anesthesia (TIVA) and volatile anesthesia on IOP. We searched multiple databases for relevant studies published before October 2019. Randomized controlled trials comparing the effects of propofol-based TIVA and volatile anesthesia on IOP during surgery were considered eligible for inclusion. Twenty studies comprising 980 patients were included. The mean IOP was significantly lower in the propofol-based TIVA group after intubation, pneumoperitoneum, Trendelenburg positioning, and lateral decubitus positioning. Moreover, mean arterial pressure and peak inspiratory pressure were also lower after intubation in the propofol-based TIVA group. Trial sequential analyses for these outcomes were conclusive. Propofol-based TIVA is more effective than volatile anesthesia during surgery at attenuating the elevation of IOP and should be considered, especially in at-risk patients.

Comparison of the effects of remifentanil and alfentanil on intraocular pressure in cataract surgery

Background:

Anesthesia for ophthalmic surgery requires management of intraocular pressure (IOP) during perioperative period. In an open eye, in conditions such as after traumatic injury or during cataract surgery, IOP increase can lead to permanent vision loss. Administration of narcotics concomitant with anesthetics has the ability to reduce this increase of IOP. This clinical trial aims to compare the efficacy of remifentanil and alfentanil in preventing an increase in IOP after administration of succinylcholine, intubation and during anesthesia.

Methods:

This double-blind clinical trial was conducted on 50 patients undergoing elective general surgery for cataracts. Patients were randomly divided into two groups. Alfentanil (20 μg/kg in 30 s) for group 1 and remifentanil (1 μg/kg in 30 s) for group 2 were injected before induction of anesthesia, and 0.5 μg/kg/min alfentanil for group 1 and 0.1 μg/kg/min remifentanil for group 2 were infused during the anesthesia. Systolic and diastolic blood pressure, heart rate, and IOP from normal eye were measured before the induction, after administration of thiopental and succinylcholine, after tracheal intubation, and 2 min later, and were repeated in 2-min intervals until the end of operation.

Results:

IOP decreased after injection of anesthetics and remained lower all through the operation in both groups, but IOP decreased after injection of succinylcholine in remifentanil group while it increased in alfentanil group (P<0.05).

Conclusions:

Results of this study indicate benefits of both remifentanil and alfentanil in managing IOP after induction and during anesthesia. It seems that remifentanil is better than alfentanil in controlling the IOP after injection of succinylcholine.