A comparison of general anesthesia versus local anesthesia in open globe injuries: A systematic review and meta-analysis

Abstract

Objective

Local anesthesia represents an alternative to general anesthesia in selected patients undergoing repair for open globe injuries. This study aimed to evaluate and compare visual acuity and clinical outcomes in such patients.

Methods

A systematic literature search was conducted across PubMed, Embase, Scopus, Cochrane Library, and Google Scholar. Adults (≥18 years) hospitalized with open globe injuries were included. Out of 551 articles screened, four observational studies met the inclusion criteria. Standardized Mean Differences (SMD) for continuous and Risk Ratios (RR) for dichotomous outcomes were pooled using the Inverse Variance method with a Random Effects model. Outcomes included visual acuity, wound location, wound length, and operative time.

Results

Four retrospective case series comprising 1,690 patients were included. All studies had low risk of bias per the Newcastle-Ottawa Scale. No significant difference was observed in best corrected visual acuity between groups (MD = −0.18; 95% CI: −0.45 to 0.08; p = 0.17; I² = 55%). Patients in the local anesthesia group had more anterior wound locations (MD = 1.33; 95% CI: 1.06–1.66; p = 0.01; I² = 65%). Wound length (MD = −4.97; 95% CI: −5.95 to −3.98; p < 0.00001; I² = 0%) and operative time (MD = -33.32; 95% CI: −40.82 to −25.82; p < 0.00001; I² = 0%) were significantly shorter.

Conclusion

Local anesthesia was associated with more anterior wounds, shorter wound length, and reduced operative time without compromising visual outcomes. It may be a safe and effective alternative to general anesthesia in selected open globe injuries.

Introduction

Open globe injuries(OGI) significantly raise the likelihood of infection and other complications such as retinal detachment, endophthalmitis and vitreous hemorrhage. ¹ They are ophthalmic emergencies that require urgent surgical repair to preserve vision and prevent complications. Over 203,000 cases of OGI are reported annually, with an estimated 3.5 injuries per 100,000 people worldwide. ¹ During open globe injury surgical repair, both general anesthesia (GA) and regional anesthesia with monitored anesthesia care (RA-MAC) can be utilized, but the two options come with their own benefits and challenges.

Historically, GA has been widely utilized for OGI. General anesthesia has the benefit of avoiding patient movements but laryngoscopy, coughing and vomiting with endotracheal intubation can cause transient elevation in intraocular pressure.^2,3 GA is associated with longer recovery and operative times, along with an elevated risk of gastric contents aspiration.^4,5

The use of RA-MAC has increased in the past two decades driven by emphasis on enhanced recovery protocols. ⁶ Patients receiving RA-MAC typically experience fewer systemic complications and avoid the risks associated with airway management. ⁷ Rapid anesthetic recovery and a shorter hospital stay are linked to the use of RA-MAC; nevertheless, patient cooperation and proper positioning are necessary, and these requirements can differ from case to case. ⁸ Concerns include increased intraocular pressure due to peribulbar or retrobulbar injections, potentially leading to intraocular content extrusion or orbital hemorrhage.^9,10 However, RA-MAC may be preferable for patients with cardiopulmonary comorbidities or contraindications to GA. ⁸

The choice of anesthesia is also dictated by the extent of the globe injury (zone of injury), extent of ocular manipulation expected to require, age and cooperation of the patient, and other facial injuries that require repair such as fractures and lacerations.^11,12 Ultimately, choice of anesthesia in OGI is personalized and considers multiple factors such as injury severity, patient comorbidity and cooperation. ⁶

The purpose of this study is to review existing literature on use of GA vs RA-MAC in surgical management of open globe injuries and synthesis of the result to identify any major differences in outcomes between the two anesthesia options for open globe injury repair.

Methods and materials

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was followed in reporting the results of this study, which was carried out in compliance with the Cochrane Handbook for Systematic Reviews of Interventions. This meta-analysis's protocol has been registered with PROSPERO under registration number CRD42025644782. Since there was no human or animal intervention in this study, Ethical Review Board (ERB) approval was not necessary.

Literature search

An electronic search was performed in Cochrane, Embase, Scopus and Google Scholar on January 22, 2024. We also searched the reference lists of related systematic reviews and possible investigations. The Medical Subject Heading (MeSH) terms or keywords included the following: (“Eye Injury”) AND (“General Anesthesia”)) AND (“Regional Anesthesia OR Local Anesthesia”)

Eligibility criteria

Inclusion Criteria: All studies that compared outcomes of GA with those of LA in adult patients (age >18 years) undergoing repair for an OGI were included. Studies published in the English language and had full text available on the internet were included only.

Exclusion Criteria: Case reports and review studies were excluded. Since GA is favored in children for improved compliance, single-arm studies and research including juvenile patients were also excluded.

Study selection and data extraction

Rayyan was used to remove duplicates of all the studies we obtained from the online search. Two authors individually screened the titles and abstracts, then the complete text according to the eligibility requirements; disagreements were resolved by consulting the third author. The details of the articles removed at every step is available in the PRISMA flow chart (Figure 1).

Figure 1.

The PRISMA flow chart showing the number of articles involved in screening process.

Relevant data was extracted including:

Baseline characteristics: total no. of patients and eyes enrolled, mean age, ratio of males and females, mean follow-up, total no. of patients and eyes analyzed, division of patients and eyes based on zone of injury, and complications.

Outcomes: mean change in best corrected visual acuity (BCVA) and logMAR, mean operative time, mean wound length, and more anterior wound location

Risk of bias and quality assessment

The Newcastle Ottawa Scale (NOS) was used to evaluate the quality and risk of bias in the included cohort and observational studies. The NOS evaluated the studies on three primary domains: the choice of study groups, their comparability, and the determination of the exposure or outcome of interest. On this scale, nine is the highest possible score. With a score of seven or more, every study was of excellent quality. The detailed scoring per domain is available in Table 1.

Table 1.

Summary of risk of bias and quality assessment.

Study	Representativeness of the exposed cohort	Selection of the non-exposed cohort	Ascertainment of exposure	Demonstration that outcome of interest was not present at the start of study	Comparability of cohorts based on the design or analysis	Assessment of outcome	Adequate follow-up	Adequacy of follow-up cohort	Total
Fan 2023	1	1	1	1	2	1	1	1	9/9
McClellan 2017	1	1	1	1	1	1	1	0	7/9
Scott 2002	1	1	1	1	1	1	1	1	8/9
Scott 2005	1	1	1	1	2	1	1	0	8/9

Data analysis

Utilizing the Review Manager Software (RevMan Version 5.4.1), the meta-analysis was carried out. ¹³ For analysis, the random effects model was employed. The measure of effect was Standardized Mean Difference (±standard deviation) for continuous outcomes (mean change in BCVA, mean wound length, and operating time), and risk ratio for dichotomous variable (more anterior wound location). For the studies not reporting the mean change in BCVA, it was calculated using the baseline and endpoint measurements via an online calculator. ¹³ The formula used was:

$$\begin{array}{rl}\mathrm{\Delta }\mathrm{Mean}=& {\mathrm{Mean}}_{\mathrm{endpoint}}\text{–}{\mathrm{Mean}}_{\mathrm{baseline}}\\ \mathrm{\Delta }\mathrm{SD}=& \surd [\mathrm{SD}{2}_{\mathrm{baseline}}+\mathrm{SD}{2}_{\mathrm{endpoint}}\\ & -(2\times \mathrm{r}\times {\mathrm{SD}}_{\mathrm{baseline}}\times {\mathrm{SD}}_{\mathrm{endpoint}}){]}^{14}\end{array}$$

To avoid the estimation bias in ΔSD, the conservative correlation coefficient of r = 0.7 was used. ¹⁴ The confidence interval was 95 percent. Utilizing the Higgins I2 statistics, statistical heterogeneity was evaluated, and the data has been presented as forest plots.

Results

Search results

The literature search retrieved 551 studies. After the exclusion of ineligible articles, reviews and duplicates, a total of 4 studies were included in this review.^15,16–18 The PRISMA flowchart provides a summary of the literature screening procedure (insert Figure 1).

Study characteristics

A total of 4 studies are included in this review and meta-analysis, reporting data on a total of 1513 patients. Every one of the four studies was carried out in the US. GA and LA were administered in 319 and 1194 cases respectively. Across all included studies, the total number of patients in the GA group with zone 1, zone 2, and zone 3 injuries was 137, 73, and 107, respectively. In comparison, LA group comprised 648 patients with zone 1 injuries, 322 with zone 2 injuries, and 121 with zone 3 injuries. The median follow-up period was 6.9 months to 20.2 months, and the median age varied from 42 to 51.8 years. Features of the listed studies are displayed in (Table 2).

Table 2.

Summary of study characteristics.

Author	Country	Study Design	Mean Age in Years (GA/LA)	No. of Patients (GA/LA)	Follow up time (GA/LA)	Outcomes	Dose	NOS	Previous Ocular History
McClellen, 2017	USA	Retrospective case series	49.3 / 51.8	97/351	8.7/12.7 (Months)	Anterior wound location, length of wound, operation time	2–4% Lidocaine + 0.75% bupivacaine + hyaluronidase	7/9	NA
Scott, 2002	USA	Retrospective, nonrandomized, comparative case series	42/49	80/140	20.2/13.9 (Months)	Anterior wound location, length of wound, operation time	2–4% Lidocaine + 0.75% bupivacaine	8/9	30 Cataract 14 Corneal Transplant 1 Primary Corneal Laceration Repair
Fan, 2023	USA	Retrospective, consecutive, comparative, non-randomized clinical study	50.52/51.26	45/462	20/16 (Months)	Anterior wound location, length of wound, operation time	0.75% or 1% ropivacaine + hyaluronidase or 4% lidocaine + 1% ropivacaine + hyaluronidase	9/9	5 Corneal Transplant (GA group)
Scott, 2005	USA	Retrospective study	45/46	97/141	7.8/6.9 (Months)	Anterior wound location, length of wound, operation time	2–4% Lidocaine + 0.75% bupivacaine + hyaluronidase	8/9	NA

Risk of bias and quality assessment

The NOS revealed that the quality of the research varied. Fan (2023) scored 9/9, having the lowest risk of bias. McClellan (2017) scored 7/9 because of inadequate follow-up. Scott (2002) lost a point in comparability while Scott (2005) lost a point in follow up, both scored 8/9. The main issue was in the domain of the randomization process and deviations in McClellan (2023) from the planned intervention. There was very little chance of bias in the other three experiments (Table 1).

Result of meta analysis

Visual acuity

All four studies reported visual acuity as an outcome. The initial (before operation) and final (after operation) visual acuity in all the studies was as reported in Table 3.

Table 3.

Patient characteristics of included studies.

Study	McClellan 2017	Fan 2023	Scott 2005	Scott 2002
Average Age Years GA/LA	49.3 + 22.2/49.3 ± 20.3	50.52/51.26	45 + 20/46 + 23	42 + 16/46 + 23
Male:Female GA/LA	69:28/244:107	31:14/366:95	75:22/105:36	65:15/101:39
Mean Presenting Vision (LogMAR)	2.72 + 0.71/1.95 + 1.04	2.6/1.9	2.7 + 0.9/1.8 + 1.2	2.5 + 0.8/1.8 + 1.1
Mean Follow up Vision	2.04 ± 1.17/1.23 ± 1.21	2.1/1.4	1.9 + 1.4/1.6 + 1.5	1.5 ± 1.2/1.1 ± 1.1
Average Wound Length in Millimeters (mm) Mean + SD GA/LA	11.9 ± 66/7.0 ± 5.6	13.6/7.9	12 + 7.9/6.5 + 4.5	10.8 ± 5.9/6.3 ± 4.8
Zone of injury I		4.2%/95.6%	34.7%/65.2%
GA/LA		8.2%/91.7%	33.8%/66.1%
Zone of injury II		24.5%/75.5%	70.7%/29.3%
GA/LA	12%/88%			32.2%/67.7%
Zone of injury III	23%/77%			26%/74%
GA/LA	53%/47%			65.5%/34.5%

Change in BCVA (LogMAR) was calculated and compared between two groups. No significant difference was observed. It highlights no significant difference in the visual outcome of the type of anesthesia used. (MD = -0.18; 95% CI: −0.45, 0.08; p = 0.17, I² = 55%) (Figure 2a).

Figure 2.

Forest plots comparing (a) visual acuity, (b) anterior wound location, (c) mean wound length and (d) mean operation time among general anesthesia versus regional anesthesia groups.

Location of anterior wound

Three studies evaluated anterior wound location as an outcome. Patients undergoing RA-MAC were more likely to have an anterior wound location (Figure 2b). In open-globe injury treatment techniques, local anesthetic is favored in patients with anterior wounds (MD = 1.33; 95%CI:1.06–1.66; p = 0.01, I² = 65%).

Length of wound

When wound length in millimeters (mm) was compared between two groups, patients undergoing RA-MAC were more likely to have smaller wound length (Figure 2c) (MD = -4.97; 95%CI: −5.95, −3.98; p < 0.00001, I² = 0%).

Operation time

All four studies included operation time (in minutes) as an outcome. The operation times were found to be significantly shorter in RA-MAC group in comparison to GA group (MD = −33.32; 95%CI: −40.82, −25.82; p < 0.00001, I² = 0%) (Figure 2d).

Discussion

This meta-analysis and comprehensive review examined the effects of GA and RA-MAC on postoperative outcomes in patients undergoing openglobe injury repair.

All included studies primarily enrolled adult patients (≥18 years), excluding pediatric populations due to the typical requirement for GA in younger individuals and concerns regarding cooperation, communication, and psychological maturity. Additionally, patients undergoing primary enucleation or evisceration, or those with prior surgical repair, were consistently excluded to ensure the analysis focused on reparable OGI. In all four included studies, most of the patients in the RA-MAC group had less severe penetrating injuries (as reflected by shorter wound lengths), and presented with more anterior wound locations, suggesting a potential selection bias in patient allocation, probably to protect the patient safety. ¹⁹ Moreover, in the GA group, the average operational time was significantly prolonged. This may be attributed to the additional time required for anesthesia induction and airway management. Another possible explanation could be the longer surgical duration observed in GA cases could be due to the selection of more complex injuries in Zone 2 and 3, which demand extensive surgical exploration and intervention. Regarding intra-operative or post-operative complications, no complications such as expulsion or prolapse of intraocular contents were reported in either GA or LA group.^4,15–17

While the RA-MAC group appeared to have better final BCVA in all included studies compared to GA, the overall change in BCVA (postoperative BCVA – preoperative BCVA) did not show a significant difference. This may be due to selection bias, as patients in the GA group had worse initial visual acuity (higher LogMAR values) at presentation (Table 1). Although it proves that RA-MAC does not provide worse outcomes. The reliability of these results is limited by the retrospective design of three studies and the brief intervals of follow-up.

There is also a significant gap in the literature regarding qualitative outcomes, including patient comfort, quality of life, as well as overall perception of the procedure. Chakraborty. et al, 2012 ²⁰ reported that patients who received regional anesthesia (peribulbar anesthesia) generally experienced greater comfort. However, since the study relied on a subjective grading system, its findings may not be reliable. To obtain more accurate insights into patient-related outcomes, future research should focus on interventional studies that utilize validated scoring systems for a more objective assessment. Also, the generalizability of findings may be limited due to unequal group sizes, baseline differences in injury severity and population, such as wound location, length, ocular trauma score, presence of afferent pupillary defects and systemic diseases which may have influenced the choice of anesthesia and affected outcomes. ²¹

GA has long been the preferred choice for emergency ophthalmic surgeries due to its ability to provide complete immobility and full muscle relaxation, which helps minimize intraoperative complications. ²² However, RA-MAC is now the emerging option ²³ as it offers analgesia but isn’t associated with akinesia or amnesia. ²⁴ Interestingly, none of the studies reviewed reported major complications such as globe rupture or endophthalmitis in either group. Whether this absence of adverse effects is purely coincidental or reflects a more meaningful trend remains unclear and warrants further investigation.

A major limitation of our study is that all the included studies were conducted in the United States, making it difficult to generalize globally. Different countries have different guidelines regarding anesthesia and patient demographics. Middle and low income countries may be more limited in their ability to provide general anesthesia. The incidence of globe injuries and severity varies across countries that can also influence anesthesia selection. Further studies outside of the United States should be done to evaluate anesthesia practices globally.

Conclusion

This review compared GA and RA-MAC for openglobe injury repair. While RA-MAC was associated with shorter wounds, more anterior wound locations, and reduced operating times, no significant difference could be determined in overall visual recovery. No major complications were reported in either group. However, given the limitations of existing studies, further studies with longer follow-ups are needed to better assess long-term outcomes and patient experience.