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

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.

Cooling Anesthesia for Intravitreal Injections - A Review

Intravitreal (IVT) injections are the most common procedure performed in retinal clinics today. It has revolutionized the treatment of neovascular age-related macular degeneration (nAMD), diabetic macular edema, macular edema due to veinous occlusive disease and other forms of exudative maculopathy. Though IVT injections prevent vision loss, the discomfort at the time of the injection has been troublesome to patients. This has led to patients missing their regular and routine dosage of treatment. Various modes of pre-injection anesthetic methods have been tried but in vain. Lidocaine-based topical anesthesia, in the form of pledgets, topical gel or subconjunctival lidocaine injection, has been the standard of care (SOC) for IVT injections worldwide. This article highlights the role of cooling anesthesia in reducing pain, anxiety and discomfort associated with needle penetration at the time of injection. PubMed and MedLine search were related to anesthesia for intravitreal injections, cooling anesthesia, mechanism of cooling anesthesia, COOL-1 trial, COOL-2 trial, results of COOL-1 trial and ultrarapid cooling anesthesia.

A Randomized Controlled Trial to Manage Postoperative Ocular Pain after Pterygium Excision with Conjunctival Autograft Transplantation with a Single Application of 2% Sodium Hyaluronate

Purpose

To assess the effectiveness of a single application of 2% sodium hyaluronate (SH) in controlling pain after pterygium excision as compared with that of a control group.

Methods

We performed a prospective randomized controlled trial in the patients who underwent pterygium excision. The outcome of topical application of 2.0% SH was measured using the visual analogue scale (VAS), in comparison with that observed in a control group (without SH). The area of ocular surface defects was assessed by ImageJ freeware. Analysis of pain scores and ocular surface defects were observed from both groups immediately after the operation, Day 0, and 3 subsequent days.

Results

Thirty patients were randomly divided into control group and SH treatment group. The initial area of the ocular surface defect on Day 0 was approximately the same for both groups (p=0.242). The medians of pain score assessed by the VAS on Days 0, 1, and 2 were 5, 3, and 0 for the SH group and 6, 5, and 3 for the control group, respectively. The pain score was statistically significantly decreased in the SH group compared to the control group on Day 1 (p < 0.001) and Day 2 (p < 0.001). The pain level of both groups was nearly the same on Day 3 (p=0.141). The area of ocular surface defects was significantly different between two groups on Day 1 (p < 0.001) and Day 2 (p < 0.001). Postoperative complications were not observed.

Conclusion

A single topical application of 2% SH in pterygium excision was effective in relieving pain in the early postoperative period without any adverse effects. This innovation may provide alternative pain control in pterygium surgery.

A Substantive Narrative Review on the Usage of Lidocaine in Cataract Surgery

Cataracts are a disease that causes a gradual decrease in visual prowess and requires surgery when the symptoms progress to an abhorrent state. This disease can be treated through surgical procedures that use anesthetics, such as lidocaine. Through inhibiting sensory nerve propagation to the brain, lidocaine plays an invaluable part in reducing pain for patients that undergo cataract surgery. Current clinical practice commonly utilizes 2% lidocaine with fentanyl as a combination agent. However, recent studies have reported that concentrations higher than 1% can cause substantial alteration to corneal epithelium cells. Additionally, fentanyl is cited as an extremely addictive opioid inappropriate for continual use in cataract surgeries. In this review, the authors examine the application and concentration of lidocaine, along with the various combination agents that were reported in several studies that describe the usage of the anesthetic during cataract surgery. Within the review, it was found that most surgeons generally only use lidocaine gel on the corneal epithelium tissue of patients during cataract surgery. Perhaps this standard could change over time as it is generally known that using intracameral injections in conjunction with topical anesthesia produces better patient outcomes. The authors find that although anesthetics and surgical treatment for cataracts are generally beneficial for patients, there are still many adjustments that could be implemented to enhance patient outcomes.

Adverse Events during Vitrectomy under Adequacy of Anesthesia-An Additional Report

The intraprocedural immobilization of selected subsets of patients undergoing pars plana vitrectomy (PPV) requires the performance of general anesthesia (GA), which entails the intraoperative use of hypnotics and titration of opioids. The Adequacy of Anesthesia (AoA) concept of GA guidance optimizes the intraoperative dosage of hypnotics and opioids. Pre-emptive analgesia (PA) is added to GA to minimize intraoperative opioid (IO) usage. The current additional analysis evaluated the advantages of PA using either COX-3 inhibitors or regional techniques when added to AoA-guided GA on the rate of presence of postoperative nausea and vomiting (PONV), oculo-emetic (OER), and oculo-cardiac reflex (OCR) in patients undergoing PPV. A total of 176 patients undergoing PPV were randomly allocated into 5 groups: (1) Group GA, including patients who received general anesthesia alone; (2) Group T, including patients who received preventive topical analgesia by triple instillation of 2% proparacaine 15 min before induction of GA; (3) Group PBB, including patients who received PBB; (4) Group M, including patients who received PA using a single dose of 1 g of metamizole; (5) Group P, including patients who received PA using a single dose of 1 g of acetaminophen. The incidence rates of PONV, OCR, and OER were studied as a secondary outcome. Despite the group allocation, intraoperative AoA-guided GA resulted in an overall incidence of PONV in 9%, OCR in 12%, and OER in none of the patients. No statistically significant differences were found between groups regarding the incidence of OCR. PA using COX-3 inhibitors, as compared to that of the T group, resulted in less overall PONV (p < 0.05). Conclusions: PA using regional techniques in patients undergoing PPV proved to have no advantage when AoA-guided GA was utilised. We recommend using intraoperative AoA-guided GA to reduce the presence of OCR, and the addition of PA using COX-3 inhibitors to reduce the rate of PONV.

Preventive Analgesia, Hemodynamic Stability, and Pain in Vitreoretinal Surgery

Background and Objectives: Although vitreoretinal surgery (VRS) is most commonly performed under regional anaesthesia (RA), in patients who might be unable to cooperate during prolonged procedures, general anaesthesia (GA) with intraprocedural use of opioid analgesics (OA) might be worth considering. It seems that the surgical pleth index (SPI) can be used to optimise the intraprocedural titration of OA, which improves haemodynamic stability. Preventive analgesia (PA) is combined with GA to minimise intraprocedural OA administration. Materials and Methods: We evaluated the benefit of PA combined with GA using SPI-guided fentanyl (FNT) administration on the incidences of PIPP (postprocedural intolerable pain perception) and haemodynamic instability in patients undergoing VRS (p < 0.05). We randomly assigned 176 patients undergoing VRS to receive GA with SPI-guided FNT administration alone (GA group) or with preventive topical 2% proparacaine (topical anaesthesia (TA) group), a preprocedural peribulbar block (PBB) using 0.5% bupivacaine with 2% lidocaine (PBB group), or a preprocedural intravenous infusion of 1.0 g of metamizole (M group) or 1.0 g of paracetamol (P group). Results: Preventive PBB reduced the intraprocedural FNT requirement without influencing periprocedural outcomes (p < 0.05). Intraprocedural SPI-guided FNT administration during GA resulted in PIPP in 13.5% of patients undergoing VRS and blunted the periprocedural effects of preventive intravenous and regional analgesia with respect to PIPP and haemodynamic instability. Conclusions: SPI-guided FNT administration during GA eliminated the benefits of preventive analgesia in the PBB, TA, M, and P groups following VRS.

Anesthesia for Intravitreal Injection: A Systematic Review

Background

The intravitreal injection has become one of the most commonly performed procedures in ophthalmology; however, there is no standardized approach to anesthesia during the procedure. The goal of this systematic review is to review approaches to anesthesia for intravitreal injection and look at comparative efficacy between these different anesthetics.

Methods

A systematic review of literature was performed in the MEDLINE, PubMed, Cochrane Library, and Clinicaltrials.gov databases using the key words “anesthesia”, “pain management”, and “intravitreal injection”. Of the initial 239 search matches, 30 articles were found to be relevant to the topic. 18 studies were excluded as they did not include primary data or did not include the visual analog scale as a primary outcome. The remaining 12 articles were assessed to look at the comparative efficacy of anesthesia and adverse events.

Results

The anesthesia techniques reported include topical methods such as anesthetic eyedrops, anesthetic gels, and anesthetic-soaked pledgets as well as subconjunctival injection of anesthetic. Ultimately, no single anesthetic or delivery mechanism was shown to be superior to the others in a statistically significant way and adverse events were largely insignificant. Limitations of these studies include relatively small sizes of the studies, as well as the lack of masking which may introduce bias.

Conclusion

In the current literature, no type of anesthetic method was found to be superior to another for intravitreal injection. Future studies in this area may lead to new insights into the efficacy of different forms of intravitreal anesthesia.

Trojan horse anaesthesia: A novel method of anaesthesia for pars plana vitrectomy

CONTEXT:

Topical anesthesia has been used for pars plana vitrectomy (PPV) with limited patient comfort. Thus, augmenting topical anesthesia with intracameral anesthesia (Trojan horse anesthesia) will provide pain-free experience during PPV.

AIMS:

This study was undertaken to evaluate the patient comfort and surgical safety using 2% lignocaine jelly augmented with intracameral 1.0% lignocaine solution for anesthetizing the eyes undergoing PPV.

SETTINGS AND DESIGN:

This was a prospective interventional case series at tertiary care hospital.

SUBJECTS AND METHODS:

Patients planned for PPV for indications other than retinal detachment were included in the study. The pain perception of the participants undergoing PPV under Trojan horse anesthesia was evaluated using visual analog scale (VAS).

STATISTICAL ANALYSIS USED:

Data analysis was done using descriptive statistics and nonparametric analysis with level of significance at P < 0.05.

RESULTS:

There were 114 eyes of 114 patients in the study out of which 68.4% (n = 78) were males. The mean age was 42.31 years (range 14–80 years, standard deviation [SD] 18.7). The mean surgical time was 34.0 min (range 13–80 min, SD 14.2). The pain perception on VAS scale averaged 3.0 (range 0–8, SD 1.59, median 3.0). Pain scores were not affected by the age (Pearson correlation = 0.098, P = 0.3), gender (P = 0.44), or the educational status of the participant (P = 0.28). The pain scores were not affected by the indications of surgery (P = 0.58) or the use of silicone oil (P = 0.07).

CONCLUSIONS:

Trojan horse anesthesia provides adequate analgesia for comfortable and safe 23-gauge PPV with high patient acceptability.

Endophthalmitis following intravitreal anti-vascular endothelial growth factor (VEGF) injection: a comprehensive review

The purpose of this review is to report and summarize previously reported studies and assess many of the individual steps of the intravitreal injection procedure's possible effect on the prevention of endophthalmitis. The pooled endophthalmitis rate from 20 large retrospective case series of anti-VEGF injections was 144/510,396 (0.028%; 1/3,544). Injections may be performed in an office-based location or in an operating room (OR) and low rates of endophthalmitis can be achieved in either location with careful attention to asepsis. Pre- or post-injection topical antibiotics have not been shown to be effective, and could select for more virulent microorganisms. Povidone-iodine prior to injection is accepted as the gold-standard antiseptic agent, but aqueous chlorhexidine may be an alternative. Antisepsis before and after gel or subconjunctival anesthetic is suggested. The preponderance of Streptococcal infections after intravitreal injection is discussed, including the possible role of aerosolization, which can be minimized by using face masks or maintaining silence. As with other invasive procedures in medicine, the use of sterile gloves, following adequate hand antisepsis, may be considered. Control of the eyelashes and lid margin is required to avoid contamination of the needle, but this can be achieved with or without a speculum. Techniques to minimize vitreous reflux have not been shown to reduce the risk of endophthalmitis. Same day bilateral injections should be performed as two separate procedures, preferably using drug from different lots, especially when using compounded drugs.

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.