The cornea is the most anterior portion of the eye and is responsible for barrier protection, filtration and refraction.1-2 Corneal abrasion (CA) is defined as a defect in the epithelial surface of the cornea,1 and is usually caused by eye trauma, such as being hit or scratched in the eye.1-5 Corneal drying can also lead to the development of CAs.3 The cornea is highly innervated by the trigeminal nerve.5 Because of this, CAs can cause pain in the eye, eye tearing, uncomfortable blinking and opening of the eye, photophobia (light sensitivity), and the sensation of a foreign body in the eye.1,4,5 Even a small abrasion can cause severe discomfort for patients.1,2,4-6 Deep CAs can lead to corneal scarring that requires corneal transplant to restore vision.2 Rarely, recurrent corneal erosion, a spontaneous disruption of the corneal epithelium, can also occur months or years after a CA.1,2
Corneal abrasions are considered the most common corneal complication that occurs in patients undergoing general anesthesia,3,6-8 and this has been documented in the literature as far back as 1965.6 The incidence of CA in patients undergoing general anesthesia varies in the literature, with reports of 0% incidence in eyes protected with tape or vaseline gauze and 44% in unprotected eyes.9 Other retrospective studies evaluating the incidence of perioperative CA indicate the incidence is 0.11% from 2007 through 2008,10 0.13% from 2007 through 2011 for a total of 118 CAs,8 0.07% from 2011 through 2013,11 and 0.04% from 2009 through 2013 for a total of 19,903 CAs.12
Corneal abrasions are diagnosed by the use of fluorescein and examination with a blue or ultraviolet light or a Wood or Burton lamp.1,4,5 Fluorescein is an orange dye that emits fluorescence when exposed to blue wavelength light used to diagnose corneal defects.13 The fluorescein is instilled in and diffuses over the eye, and the eye is then examined with the blue or ultraviolet light or Wood or Burton lamp to see if any part of the eye emits a yellow-green color.1,4,5,13 If any part of the cornea is stained, the diagnosis of CA is made.1,4,5,13 With regards to perioperative CAs, complaints of pain and/or diagnosis of CA have been reported to occur within three hours from the end of anesthesia.10,14,15
Corneal abrasions often heal spontaneously in less than 72 hours, and treatment usually involves topical antibiotic ointment as well as both topical and oral nonsteroidal anti-inflammatory (NSAID) pain relievers.1,2,4 In the United States, the cost of topical NSAIDs can range from $20 to $164 for 5 mL.1,2 The cost for topical antibiotics can range from $3 to $132. In severe cases oral opioid analgesics may be needed to control pain.1 Topical anesthetics are safe, effective and cheaper than NSAIDs in treating perioperative CAs, although actual costs have not been identified.16
In addition to the cost of treatment described above, when CAs occur perioperatively, there is potential for increased costs related to malpractice claims, as demonstrated by Gild et al.7 in a closed claim analysis from 1985 to 1990.7 Eye injuries demonstrated 3% of all claims, and CA accounted for 35% of these claims for a total of 25 claims.7 Payouts made to 16 of these claims ranged from $25 to $25,000 with a median payment of $3000.7 Corneal abrasions that occur perioperatively are also associated with increased length of stay.10
Patients undergoing general anesthesia are at risk for perioperative CAs due to loss of corneal protective reflexes, decreased tear production and incomplete closure of the eyelid.16,17 Other risk factors have not been agreed upon by the authors in the literature. The following have been identified as possible risk factors: head and neck surgery,14,15 longer anesthesia time,6,8,9,11,14 prominent anatomic structure of the eye,6 hypertension,12 smoking,12 obesity,12 large estimated blood loss,10 same day admission,10 increased length of post anesthesia care unit (PACU) stay,10 oxygen administration in the PACU,10 surgery on Monday,14 and pre-existing eye disease (history of ocular surgery or dry eye diagnosis).11
There are several conflicts in the literature surrounding risk factors for perioperative CA. Paradoxically, Segal et al.10 found that taping of the eyelids, a common perioperative CA prevention strategy discussed below, increased incidence of CAs. Roth et al.14 found that increased age, while associated with CA, was not an independent risk factor, whereas Lichter et al.8 and Segal et al.10 identified older age as a risk factor. The supine,12 prone,15 Trendelenburg10 and lateral positions14,18 have been identified as risk factors for the development of perioperative CA; however it has also been reported that position is not a risk factor.11
While incidence of CA in relation to geographic location has not been specifically studied in the literature, it can be postulated that it is not isolated to a particular area, as evidenced by the literature coming from the United States,4,7,8,10-12,14-16,19,20 the United Kindgom,17,21 India,9,18 China22 and Turkey.23,24
Perioperative CA prophylaxis has been present in the literature as early as 1965, with recommendations of keeping the eyes completely closed and when this is not feasible, instilling a bland ophthalmic solution.6,15 Current recommendations for the prevention of CAs in patients undergoing general anesthesia mirror this and include ensuring eye lid closure and securing with tape.3 Another current preventative measure includes application of preservative free lubrication to the cornea.16 It should be noted that some studies have demonstrated adverse side effects of lubrication such as blurred vision24,25 and ocular edema.25 Several studies on the prevention of perioperative CAs with a focus on tape and/or eye lubrication have been noted after a brief literature review.9,18-20,22-24 Two literature reviews have been published relating to perioperative CA prevention interventions.17,21 Neither of these reviews meet systematic review standards due to the absence of assessment of methodological quality, standardized data extraction and data synthesis. Therefore, a systematic review on the effectiveness of CA prevention interventions in patients undergoing general anesthesia is needed.
This review aims to identify the effectiveness of eye lubrication, tape and/or the combination of these interventions in preventing CAs in adult patients aged 18 and over undergoing general anesthesia for more than one hour.
A search of Ovid MEDLINE, CINAHL, Cochrane, and JBI Database of Systematic Reviews and Implementation Reports found no published or proposed protocols or systematic reviews on interventions for prevention of CAs.
This review will consider studies that include patients aged 18 years and over undergoing general anesthesia for any procedures, excluding those on the eye, for more than one hour. Studies will be excluded if they include patients with pre-existing eye trauma or injury including but not limited to lacerations/cuts to the eye, penetrating injuries to the eye, chemical injuries to the eye, and eye contusions.
This review will consider studies that evaluate the use of eye lubrication, tape and/or any combinations of the above interventions in their effectiveness to prevent CAs. Eye lubrication is defined as any eye lubricant, drop or ointment instilled in the eye for the purpose of preventing dryness. Tape is defined as any type of adhesive, paper or semi-occlusive dressing utilized for the purpose maintaining eye closure.
This review will compare studies that compare the above interventions to each other or no intervention.
Types of studies
This review will consider both experimental and quasi-experimental study designs including randomized controlled trials, non-randomized controlled trials, before and after studies and interrupted time-series studies. In addition, analytical observational studies including prospective and retrospective cohort studies, case-control studies and analytical cross-sectional studies will be considered for inclusion. This review will also consider descriptive observational study designs including case series, individual case reports and descriptive cross-sectional studies for inclusion.
This review will consider studies that include the following primary outcome measure: CAs. This outcome will be measured by CA diagnosis by fluorescein stain by any medical professional (ophthalmologist, anesthesiologist, etc.) trained in the use of fluorescein within three hours from the end of anesthesia to limit the chance that the CA occurs during a period other than while under general anesthesia. This review will also evaluate a primary outcome measure of eye pain within three hours from the end of anesthesia. Eye pain will be measured by the Numeric Pain Scale, a numeric rating scale with proven validity, with zero being no pain and 10 being the worst imaginable pain.26 The outcomes of CAs and eye pain will be evaluated postoperatively within three hours of the general anesthetic time. This review will also evaluate secondary outcomes of blurred vision measured by participant survey or Snellen Chart27 and ocular edema measured by visual inspection, where available.
The search strategy will aim to find both published and unpublished studies. An initial limited search of MEDLINE and CINAHL has been undertaken followed by analysis of the text words contained in the title and abstract, and of the index terms used to describe articles. This informed the development of a search strategy which will be tailored for each information source. The full search strategy for CINAHL is detailed in Appendix I. The reference list of all studies selected for critical appraisal will be screened for additional studies. Studies published in English will be included. Searches of the databases from the date of inception will be conducted as there has never been a systematic review performed on CA prevention interventions.
The databases to be searched include: CINAHL, Ovid MEDLINE, Embase, Scopus and Web of Science.
The trial registers to be searched include: Cochrane CENTRAL Register of Controlled Trial and ClinicalTrials.gov.
The search for unpublished studies will include: ProQuest Dissertations and Theses, ProQuest Nursing and Allied Health Database, Google Scholar and New York Academy of Medicine Grey Literature Collection.
Following the search, all identified citations will be collated and uploaded into RefWorks (ProQuest LLC, Ann Arbor, USA) and duplicates removed. Titles and abstracts will then be screened by two independent reviewers for assessment against the inclusion criteria for the review. Studies that meet or could potentially meet the inclusion criteria will be retrieved in full and their details imported into the Joanna Briggs Institute's System for the Unified Management, Assessment and Review of Information (JBI SUMARI).28 The full text of selected studies will be retrieved and assessed in detail against the inclusion criteria. Full text studies that do not meet the inclusion criteria will be excluded and reasons for exclusion will be provided in an appendix in the final systematic review report. Included studies will undergo a process of critical appraisal. The results of the search will be reported in full in the final report and presented in a Preferred Reporting Items of Systematic reviews and Meta-Analyses (PRISMA) flow diagram.29 Any disagreements that arise between the reviewers will be resolved through discussion, or with a third reviewer.
Assessment of methodological quality
Selected studies will be critically appraised by two independent reviewers at the study level for methodological quality in the review using the standardized critical appraisal instruments from JBI for the following study types:30 case control studies, case reports, case series, cohort studies, quasi-experimental studies, randomized controlled trials, and analytical cross sectional studies. Any disagreements that arise will be resolved through discussion, or with a third reviewer.
All studies, regardless of their methodological quality, will undergo data extraction and synthesis, where possible.
Data will be extracted from papers included in the review using the standardized data extraction tool available in JBI SUMARI30 by two independent reviewers. The data extracted will include specific details about the interventions, populations, study methods and outcomes of significance to the review question and specific objectives. Any disagreements that arise between the reviewers will be resolved through discussion or with a third reviewer. Authors of papers will be contacted to request missing or additional data where required.
Studies will, where possible, be pooled in statistical meta-analysis using JBI SUMARI.30 Effect sizes will be expressed as either odds ratios (for dichotomous data) and weighted (or standardized) mean differences (for continuous data) and their 95% confidence intervals will be calculated for analysis. Heterogeneity will be assessed statistically using the standard chi-squared and I squared tests. The choice of model (random or fixed effects) and method for meta-analysis will be based on the guidance by Tufunaru et al. 2015.31
Subgroup analyses will be conducted where there is sufficient data to investigate. Subgroups of interest for this systematic review include side effects of the interventions including blurred vision and ocular edema based on intervention type. Sensitivity analyses will be conducted to explore the impact of study quality of any included clinical trials. Where statistical pooling is not possible the findings will be presented in narrative form including tables and figures to aid in data presentation where appropriate.
A funnel plot will be generated to assess publication bias if there are 10 or more studies included in a meta-analysis. Statistical tests for funnel plot asymmetry (Egger test, Begg test, Harbord test) will be performed where appropriate.
Assessing certainty in the findings
A Summary of Findings will be created using GRADEPro GDT software.32 The Grading of Recommendations Assessment, Development and Evaluation (GRADE)33 approach for grading the quality of evidence will be followed. The Summary of Findings will present the following information where appropriate: absolute risks for treatment and control, estimates of relative risk, and a ranking of the quality of the evidence based on study limitations (risk of bias), indirectness, inconsistency, imprecision and publication bias.
The following outcomes will be included in the Summary of Findings: diagnosis of CA postoperatively and diagnosis of eye pain postoperatively.
This systematic review is conducted as a partial fulfillment of a Doctor of Nursing Practice degree for Nurse Anesthesia through Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA, for AM, LB, and MB. The authors would like to thank Julie Schiavo for her assistance in database searches.
Appendix I: Search strategy
S1 (MH “Eye Injuries+/PC”) OR (MH “Corneal Injuries/PC”)
S2 (MH “Eye”) OR “eye” OR (MH “Cornea”) OR “cornea”
S3 (MH “Wounds and Injuries/PC”)
S4 (“prevention and control” OR prevent*) AND injur*
S5 injury N3 prevention
S6 “general anesthesia” OR (MH “Anesthesia, General”)
S7 (MH “Surgical Patients”) OR “surgical patient”
S8 (MH “Intraoperative Complications/PC”)
S9 (MH “Intraoperative Period”) OR (MH “Perioperative Care”)
S10 (MH “Eye Protective Devices”) OR “eye protective devices” OR (eye N3 protect*) OR (cornea* N3 protect*)
S11 ophthalmic solutions
S12 (MH “Ophthalmic Solutions”) OR “eye drops” OR “artificial tear*”
S13 eye lubricant
S14 (MH ”Lubricants“) OR ”lubricant*“
S15 ”eye ointment“
S16 (MH ”Ointments“) OR ”ointment*”
S17 “tape” OR (MH “Tapes”)
S18 S2 AND S3
S19 S4 OR S5
S20 S2 AND S19
S21 S1 OR S18 OR S20
S22 S6 OR S7 OR S8 OR S9
S23 S11 OR S12 OR S13 OR S14 OR S15 OR S16
S24 S17 AND S23
S25 S10 OR S24
S26 S21 AND S22 AND S25
NOTES: The default fields for unqualified searches consist of the following: title, abstract and subject headings.
1. Wipperman JL, Dorsch JN. Evaluation and management of corneal abrasions. Am Fam Physician
2013; 87 2:114–120.
2. Wilson SA, Last A. Management of corneal abrasions. Am Fam Physician
2004; 70 1:123–128.
3. Harvey R. Nurse Anesthesia. Fifth edition.2014; US: Saunders, 976–998.
4. Browner EA. Corneal abrasions. Pediatr Rev
2012; 33 6:285–286.
6. Terry HR, Kearns TP, Love JG, Orwoll G. Untoward ophthalmic and neurologic events of anesthesia. Surg Clin North Am
1965; 45 4:927–929.
7. Gild WM, Posner KL, Caplan RA, Cheney FW. Eye injuries associated with anesthesia: A closed claims analysis. Anesthesiology
1992; 76 2:204–208.
8. Lichter JR, Marr LB, Schilling DE, Hudson ME, Boretsky RH, Barad RF, et al. A Department-of-Anesthesiology-based management protocol for perioperative corneal abrasions. Clin Ophthalmol
9. Batra YK, Bali IM. Corneal abrasions during general anesthesia
. Anesth Analg
1977; 56 3:363–365.
10. Segal KL, Fleischut PM, Kim C, Levine B, Faggiani SL, Banerjee S, et al. Evaluation and treatment of perioperative corneal abrasions. J Ophthalmol
2014; 2014: Article ID 901901.
11. Carniciu AL, Fazzari MJ, Tabibian P, Batta P, Gentile RC, Grendell JH, et al. Corneal abrasion
following anaesthesia for non-ocular surgical procedures: A case-controlled study. J Perioper Pract
2017; 27 11:247–253.
12. Wastler KE, Grichnik K, Noeth T, Beck JE. Letters. AANA J
2015; 83 1:15–16.
14. Roth S, Thisted RA, Erickson JP, Black S, Schreider BD. Eye injuries after nonocular surgery: A study of 60,965 anesthetics from 1988 to 1992. Anesthesiology
1996; 85 5:1020–1027.
15. Snow JC, Kripke BJ, Norton ML, Chandra P, Woodcome HA. Corneal injuries during general anesthesia
. Anesth Analg
1975; 54 4:465–467.
16. Malafa MM, Coleman JE, Bowman RW, Rohrich RJ. Perioperative Corneal Abrasion
: Updated Guidelines for Prevention and Management. Plast Reconstr Surg
2016; 137 5:790e–798e.
17. White E, Crosse MM. The aetiology and prevention of peri-operative corneal abrasions. Anaesthesia
1998; 53 2:157–161.
18. Grover VK, Kumar KVM, Sharma S, Sethi N, Grewal SPS. Comparison of methods of eye protection
under general anaesthesia. Can J Anaesth
1998; 45 6:575–577.
19. Orlin SE, Kurata FK, Krupin T, Schneider M, Glendrange RR. Ocular lubricants and corneal injury during general anesthesia
. Anesth Analg
1989; 69 3:384–385.
20. Siffring PA, Poulton TJ. Prevention of ophthalmic complications during general anesthesia
1987; 66 4:569–570.
21. Grixti A, Sadri M, Watts MT. Corneal protection during general anesthesia
for nonocular surgery. Ocul Surf
2013; 11 2:109–118.
22. Wan T, Wang Y, Jin X. Corneal injury and its protection using hydro-gel patch during general anesthesia
. Int J Ophthalmol
2014; 7 6:964–967.
23. Kocaturk O, Kocaturk T, Kaan N, Dayanir V. The comparison of four different methods of perioperative eye protection
under general anesthesia
in prone position. J Clin Analyt Med
2012; 3 2:163–165.
24. Ganidagli S, Cengiz M, Becerik C, Oguz H, Kilic A. Eye protection
during general anaesthesia: comparison of four different methods. Eur J Anaesthesiol
2004; 21 8:665–667.
25. Boggild-Madsen NB, Bundgarrd-Nielsen P, Hammer U, Jakobsen B. Comparison of eye protection
with methylcellulose and paraffin ointments during general anaesthesia. Can Anaesth Soc J
1981; 28 6:575–578.
26. Ferreira-Valente MA, Pais-Ribeiro JL, Jensen MP. Validity of four pain intensity rating scales. Pain
2011; 152 10:2399–2404.
28. The Joanna Briggs Institute. The System for the Unified Management, Assessment and Review of Information (SUMARI). 2017. Available from: https://www.jbisumari.org
29. Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Int J Surg
2010; 8 5:336–341.
30. The Joanna Briggs Institute. Joanna Briggs Institute Reviewers’ Manual: 2017 edition. Australia: The Joanna Briggs Institute; 2017.
31. Tufanaru C, Munn Z, Stepheson M, Aromataris E. Fixed or random effects meta-analysis? Common methodological issues in systematic review of effectiveness. Int J Evid Based Healthc
2015; 13 3:196–207.
32. GRADEpro GDT: GRADEpro Guideline Development Tool [Software]. McMaster University, 2015 (developed by Evidence Prime, Inc.). Available from gradepro.org.
33. Guyatt Gordon H, Oxman Andrew D, Vist Gunn E, Kunz Regina, Falck-Ytter Yngve, Alonso-Coello Pablo, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ