The Effects of Low Viscosity Preservative-Free Chloroprocaine Ophthalmic Gel 3% versus BAK-Containing Tetracaine 0.5% on the Bactericidal Action of Povidone-Iodine

Purpose

To evaluate if chloroprocaine ophthalmic gel 3% acts as a barrier to the bactericidal actions of povidone-iodine (PVI) which has been seen in other higher viscosity gel anesthetics.

Methods

This was a single site, prospective, randomized, patient-masked study evaluating the effects of preservative-free chloroprocaine ophthalmic gel 3% (IHEEZO®, Harrow, Nashville, TN) compared with tetracaine ophthalmic solution 0.5% and their effects on the bactericidal action of povidone-iodine 5%. The study comprised 82 patients who had both eyes cultured before and after application of randomized treatment and povidone-iodine.

Results

In terms of mean percent reduction in colony forming units, chloroprocaine with povidone-iodine was non-inferior to tetracaine with povidone-iodine, with a higher mean percent reduction in colony forming units in the chloroprocaine group (change [∆] = -7.2; 90% CI, -13.56 to 3.28).

Conclusion

Data collected in this study suggest that preservative-free chloroprocaine ophthalmic gel 3% does not act as a barrier to the bactericidal actions of povidone-iodine 5% and that the reduction in CFU from PVI is similar when compared with tetracaine 0.5% ophthalmic solution with PVI.

Chloroprocaine 3% Gel as a Novel Ocular Topical Anesthetic: Results from a Multicenter, Randomized Clinical Trial in Patients Undergoing Cataract Surgery

Purpose: To compare the efficacy and safety of a novel ophthalmic anesthetic, chloroprocaine 3% gel to tetracaine 0.5% eye drops in patients undergoing cataract surgery with phacoemulsification. Methods: This was a prospective, randomized, multicenter, active-controlled, masked-observer, parallel group competitive equivalence study. The study comprised 338 patients having routine cataract extraction by clear corneal phacoemulsification, randomized to receive 3 drops of chloroprocaine gel (n = 166) or tetracaine eye drops (n = 172) before surgery. The primary objective of the study was to assess the equivalence of chloroprocaine gel to tetracaine eye drops as proportion of patients with successful ocular surface anesthesia, without any supplementation just before intraocular lens implantation. Safety measurements were pain, irritation, burning, stinging, photophobia, and foreign body sensation, graded by the patient and objective ocular signs. Results: Equivalence was demonstrated, with a somewhat higher success rate of chloroprocaine gel: 152/166 (92.0%) chloroprocaine versus 153/172 (90.5%) tetracaine patients achieved ocular surface anesthesia with no supplementation. Difference in proportions was 1.5% confidence interval [95% CI: (-3.6 to 6.6)] and 90% CI fell within (-10 to 10). Mean onset of anesthesia was 1.35 ± 0.87 min for chloroprocaine and 1.57 ± 1.85 for tetracaine (P = 0.083). Mean duration of anesthesia was 21.57 ± 12.26 min for chloroprocaine and 22.04 ± 12.58 for tetracaine (P = 0.574). No treatment emergent adverse events related to chloroprocaine were reported and no relevant findings related to local tolerance or vital signs were observed in both arms. Conclusions: Results obtained from the present cataract study demonstrated that chloroprocaine 3% ophthalmic gel is safe and effective, representing a valid alternative in ocular topical anesthesia. Clinical Trial Registration number: NCT04685538.

Two Randomized, Double-masked, Placebo-controlled Studies of the Local Anesthetic Effect of Articaine Ophthalmic Solution

Background

We wanted to develop a new topical ocular anesthetic with good bioavailability in anterior segment tissues. Given concerns about contamination and sterility in multi-dose products, we selected a unit-dose, nonpreserved presentation of AG-920 (articaine ophthalmic solution) in blow-fill-seal containers (similar to currently marketed pharmacological therapies for dry eye disease).

Methods

Consistent with US Food and Drug Administration guidance, two pivotal, Phase 3, randomized, placebo-controlled, double-masked, parallel design studies conducted at two US private practices in 240 healthy subjects. A single dose of AG-920 or identical looking placebo into one (study) eye (2 drops 30 s apart). Subjects underwent a conjunctival pinch procedure and assessment of the pain associated with the pinch. The main outcome measure was the proportion of subjects with rating of "No pain at 5 minutes".

Results

AG-920 provided a rapid onset of local anesthesia (less than one minute) with clinically and statistically significantly greater effect in AG-920 (68% and 83%) than placebo (3% and 18% for Study 1 and Study 2, respectively, P<0.0001). The most frequent adverse event was instillation site pain (27% vs 3%) followed by conjunctival hyperemia (probably related to the pinch, 9% vs 10%) in the AG-920 and placebo groups, respectively.

Conclusion

AG-920 was found to be have a rapid onset and useful duration of local anesthesia with no major safety issues, and may be useful for the eye-care professional. Registered with clinicaltrials.gov as NCT04513652 and NCT04829344.

The Effectiveness of 2% Lidocaine Gel Compared to 0.5% Tetracaine Eye Drop As Topical Anesthetic Agent for Phacoemulsification Surgery

Background

Topical anesthetics have become the primary choice in phacoemulsification procedures for cataract extraction. The most common topical anesthetic drug used is 0.5% tetracaine eye drops. Repeated administration of 0.5% tetracaine drops can cause corneal epithelial damage. Two percent lidocaine gel is latest option which has longer contact time with corneal epithelium.

Objectives

To compare the effectiveness of 2% lidocaine gel with 0.5% tetracaine drops in phacoemulsification surgery.

Methods

The study was a single blinded randomized clinical trial from March to July 2017 in patients underwent phacoemulsification cataract surgery. There were 72 subjects with age ≥ 40 years old who received randomization and divided into 2 groups: 2% lidocaine gel group and 0.5% tetracaine eye drop group. Topical anesthetics were applied 5 minutes before surgery. Five minutes after surgery, pain scale perceived during surgery was assessed by using a numerical rating scale. At the end of surgery, the subject filled the satisfaction questionnaire on topical anesthetic drugs administered. The ophthalmologists were also given a satisfactory questionnaire for topical anesthetic drugs selected for the procedure.

Results

The median pain scale for 2% lidocaine gel group pain scale was 1; meanwhile, the median pain scale for 0.5% tetracaine eye drops was 3 (P < 0.05).

Conclusions

Two percent lidocaine gel was more effective in relieving pain during phacoemulsification cataract surgery compared with 0.5% tetracaine drops.

Patient pain during intravitreal injections under topical anesthesia: a systematic review

Background

Intravitreal injection (IVI) is a very common vitreoretinal procedure, and multiple injections are often required per patient. This systematic review was conducted to evaluate the effectiveness of various local anesthetic techniques in reducing pain during injection.

Methods

A systematic review was conducted based on searches of Cochrane, LILACS, PubMed, Scopus, Web of Science, and the gray literature (Google Scholar). The end search date was February 19, 2016, across all databases. We classified pain by converting visual analog scale (VAS) scores (0–100 mm) into Jensen’s classification levels: 0–4, no pain; 5–44, mild pain; 45–74, moderate pain; and 75–100, severe pain. An intervention was considered clinically significant when pain score change was >12 mm on a 100-mm scale.

Results

Eight studies out of 23 met the eligibility criteria. The total number of patients was 847. Most studies (5/8 [62.5%]) were at unclear risk of bias because of unclear randomization, thus providing only moderate evidence to this review. The anesthetic techniques included eye drops with proparacaine, tetracaine or cocaine, a lidocaine pledget or gel, and subconjunctival injection of 2% lidocaine or 0.75% levobupivacaine. No study comprised all of the techniques. Pain was mild (VAS scores, 5–44 mm) regardless of anesthetic technique. A clinically significant intervention (pain score change >12 mm) was found for only one study comparing proparacaine drops, lidocaine gel, and subconjunctival lidocaine; in that study, a subconjunctival injection of 2% lidocaine provided the greatest pain reduction. A meta-analysis was not possible due to study heterogeneity.

Conclusions

Patient pain during IVI under topical anesthesia is mild regardless of anesthetic technique. A subconjunctival injection of 2% lidocaine could be an option for highly sensitive patients. However, with moderate level of evidence, no single anesthetic technique could be defined as the best option for IVI.

Electronic supplementary material

The online version of this article (doi:10.1186/s40942-017-0076-9) contains supplementary material, which is available to authorized users.

Comparative Study Between Lidocaine Gel 2% and 5% for Ophthalmic Procedures

PURPOSE

To compare same-day pain control and safety of 2 different anesthetic gels utilizing 5% and 2% lidocaine gel. Main outcome is to determine whether 5% lidocaine gel is more effective in decreasing pain during conjunctival clamping compared to 2% lidocaine gel 5 and 10 min after gel application.

METHODS

This is a prospective, randomized double-blind clinical trial. Patients were randomized to receive 2% or 5% lidocaine gel in each eye. Discomfort during the gel instillation and pain during conjunctival clamping 5 and 10 min after gel application were compared. Extent of corneal conjunctival staining was graded according to the Oxford scale.

RESULTS

Eighty eyes of 40 patients were enrolled. The groups were similar in gender, with a mean age of 48 ± 16.26 years. The 5% lidocaine gel resulted in higher discomfort during initial instillation (P = 0.092), however, the pain during conjunctival clamping was lower in the 5% lidocaine gel eyes (P = 0.564) in both 5 and 10 min later (P < 0.001). The majority of patients (80%) had no corneal conjunctival dye staining. The tear break-up time was not statistically different after lidocaine gel 2% (20.35 ± 7.37 s) and lidocaine 5% (19.75 ± 7.00 s).

CONCLUSION

Five percent and 2% lidocaine gel have similar efficacy controlling pain 5 min after instillation, however, 5% lidocaine gel appears to be more effective with a longer duration of action, without corneal toxicity. There was no corneal toxicity noted with either concentration.

Lidocaine Cyclodextrin complex Ophthalmic Drop, a New Topical Anesthetic Choice

BACKGROUND

Topical anesthesia is a safe and cost-effective method considered as the first-choice in many procedures. Due to the physiological characteristics of eye, most of the local anesthetics cannot efficiently penetrate through the conjunctiva deep to tenon. The aim of this pilot study was to find a new form of lidocaine to give a sufficient level of anesthesia.

METHODS

Lidocaine Cyclodextrin complex ophthalmic drop was produced and its pharmacological properties were studied [tested] in standard temperature and pressure. 30 patients (18 males, 12 females) with the mean age of 30.68±8.02 years enrolled in this clinical trial. All the patients were fully informed and signed the ethics committee consent forms. The patients were given tetracaine drop as the anesthetic: 3 drops separated 2 minute apart 10 min before the intervention. If we achieved a sufficient level of anesthesia, the procedure was done after. If the patient could not tolerate the procedure, the method was changed to lidocaine drop (administered after wash-out period like the first drop).The last option was conventional injection method if the patient could not tolerate the procedure with the second method either.We used this type of anesthesia for conventional procedures such as forced duction test, symblepharon, pterygium, and disport injection into extra-ocular muscles. All the procedures were done by one surgeon in a university hospital. We used a 0 to 10 visual analogue scale for pain and two 0 to 4 patient and physician satisfaction scales designed for this study.

RESULTS

The mean pain score was 7.53±0.90 in group 1 and 3.03±1.83 in group 2 (P=0.00). Patient and surgeon satisfaction in group 1 were 1.33±0.48 and 1.40±0.56 respectively; while 3.23±1.00 and 3.56±0.77 for group 2 (P=0.00). Tetracaine drop could not induce sufficient anesthesia for none of the patients. Cyclodextrin based lidocaine drop was successful except For two patients for whom we changed the anesthesia to Sub-conjunctival injection method.

CONCLUSION

Our newly manufactured cyclodextrin based lidocaine eye drop could successfully induce sufficient anesthesia for 28 of 30 patients. Further studies with larger sample sizes are now being designed to find more clinical evidence about this method.

Overview of ocular anesthesia: past and present

PURPOSE OF REVIEW

Many choices of ocular anesthetic techniques are available to the ophthalmologist. This study reviews currently used techniques of topical, subconjunctival and regional block anesthesia used in ophthalmic procedures.

RECENT FINDINGS

The choices of anesthetics that are available are considered and a new ocular anesthetic gel is described that provides sustained ocular surface anesthesia, minimal side-effects and may also have antimicrobial properties.

SUMMARY

Consideration of ocular anesthetic techniques and anesthetic choice plays a critical role for the success and safety of ophthalmic surgery.

A novel lidocaine hydrochloride ophthalmic gel for topical ocular anesthesia

Topical anesthetics play an important role in the practice of ophthalmology, both for procedures in the office and in the operating room. The need for safe, long-acting topical ocular anesthetic agents is ongoing, and has been highlighted by the increase of intravitreal administration of pharmacologic agents. Current practices for ocular anesthesia include subconjunctival injection of 2% aqueous lidocaine, topical 2% lidocaine drops and topical 0.5% tetracaine. Tetracaine is not yet FDA approved, and is associated with corneal epithelial toxicity and delayed epithelial healing after multiple administrations. Lidocaine jelly (2%) preparations have been reported to be beneficial in several systemic procedures, including those of the upper airway, dental, urogenital, and gastrointestinal. It has been theorized, and recent studies support the idea, that gel formulations of lidocaine may enhance anesthetic effect, and therefore be superior to anesthetic solutions for topical cataract surgery. The viscous nature of gel formulations is thought to lengthen contact time, resulting in better anesthesia at lower drug concentrations. Furthermore, several studies suggest that lidocaine is bactericidal and bacteriostatic, and may have a supplementary role in preventing and treating surgical site infections. Akten™, lidocaine 3.5% gel (Akorn, Buffalo Grove, IIlinois) was FDA approved for all ophthalmic procedures in October 2008. This gel is a preservative-free, lidocaine-based anesthetic gel consisting of 35 mg/mL of lidocaine hydrochloride. We describe the properties, including chemical structure, indications, evidence of support, use, adverse effects, and precautions, which we believe enable Akten to provide superior anesthesia, while minimizing side effects.

Safety, efficacy, and patient acceptability of lidocaine hydrochloride ophthalmic gel as a topical ocular anesthetic for use in ophthalmic procedures

Purpose:

To review the current literature on safety, efficacy, and measures of surgeon and patient satisfaction with lidocaine hydrochloride gel as a tool for ocular anesthesia.

Methods:

Pubmed search using keywords “lidocaine gel,” “ophthalmic,” and “surgery” and compiling cross-references. Twenty-six total references were reviewed, including 15 prospective randomized controlled trials (RCTs, total N = 933, average N = 62), 6 nonrandomized prospective studies (total N = 234, average N = 39), 2 animal studies, 1 microbiologic study, and 2 letters to the editor.

Results:

The RCTs and nonrandomized prospective studies evaluated a number of measures including timing of onset of anesthesia, duration of anesthesia, intraoperative and postoperative pain, need for additional anesthetic applications, intracameral lidocaine levels, and adverse effects. Control groups received topical drops, subconjunctival anesthetic, retrobulbar anesthetic, or sham gel. Lidocaine gel was shown to be at least as effective for pain control as alternative therapies in all studies, with longer duration of action than topical drops. Patient and surgeon satisfaction were high, and adverse effects were rare and comparable to those for anesthetic drop formulations. Surgical settings included cataract, pterygium, trabeculectomy, strabismus, intravitreal injection, vitrectomy, and penetrating keratoplasty.

Conclusions:

Lidocaine gel is a safe, effective, and potentially underutilized tool for ophthalmic surgery.

Endocapsular deep-wedge-removal phacofracture

We present a nucleus disassembly technique that allows safe debulking of two thirds of the nucleus by removal of a deep, central, equilateral triangular wedge of nucleus with no manipulation or rotation. The resulting equilateral triangular wedge-shaped cavity yields 3 points of weakness at each corner that facilitate cracking the remaining peripheral nuclear rim into 3 equal segments. Each segment is easily gripped by short bursts of phaco power and pulled into the central cavity for safe endocapsular phacoemulsification, an approach that protects the cornea. This technique is applicable to most cataracts regardless of consistency. It prevents zonular stress by avoiding manipulation or rotation of the nucleus in cases in which zonular weakness is a concern. The technique was used in 95 consecutive eyes, with no posterior capsule tears, vitreous loss, or zonule disturbance.