Title: Incidence of ICU Exposure Keratopathy: A Systematic Review
Author(s): Victoria Quintero-Riestra, BS; Sergul Erzurum, MD; Timothy Barreiro, DO; Jennifer McKay, PharmD; David Gemmel, PhD
Email: vquinteroriestra@neomed.edu
Introduction: Exposure keratopathy secondary to prolonged environmental ocular surface exposure can lead to severe and irreversible damage to the cornea, leading to significant vision impairment or permanent vision loss. The tear film, vital for protection, lubricates and defends against bacteria. Proper distribution relies on blink reflexes, rate, and eyelid closure. Imbalance in these factors precipitates epithelial damage, increasing risk of ulceration, infection, and long-term vision impairment. Intensive care unit (ICU) patients face heightened risk due to factors such as immobility, mechanical ventilation, sedation, reduced consciousness, and ambient lighting. Many studies in the past have discussed exposure keratopathy, but actual incidence remains uncertain. The objective was to review existing literature on incidence of exposure keratopathy.
Discussion of Literature Review:
Methods: The database PubMed was used to retrieve studies: search terms were incidence, keratopathy and ICU. Additionally, references pages of articles were reviewed to identify other pertinent literature meeting the specified criteria. These criteria included reporting an incidence rate, specified diagnostic criteria, and methods based on number of patients. Among 21 identified studies, 11 were selected for thorough review and analyzed. Ten studies were excluded which measured prevalence rather than incidence, failing to explicitly exclude participants with any ocular disease at study onset, or assessing incidence rates based on the number of eyes or evaluations. Variables included year of publication, title, authors, setting, study design (retrospective or prospective), diagnostic criteria, method of diagnosis, evaluator, standard eye care protocols, and risk factors.
Results: The average incidence rate of exposure keratopathy was 26.4 ± 22.2%. When the weighted average rate was tabulated, exposure keratopathy incidence was 4.5%. Five study incidence rates were > 1SD or < 1SD, suggesting wide variance across sites. Although not statistically significant, incidence rates were lower in the most recent reports (R = -0.31, P = 0.352). ICU staff identified exposure keratopathy at a rate of 45%, however, when evaluators were ophthalmologists or trained investigators, the rate dropped to 21%. In these studies methodology for identifying exposure keratopathy, most frequently slit lamp and fluorescein staining, was not identified and almost no exposure keratopathy was reported, 0.05 and 0.79% (Demirel et alt., 2013).
Conclusion: This review highlights the challenge of establishing a standardized incidence rate for exposure keratopathy in the ICU due to inconsistent reporting, evaluation, and diverse settings. Common interventions to prevent keratopathy include frequent lubrication and protective eye covers. Future studies are needed to standardize diagnostic criteria, evaluate prevention effectiveness, and explore interventions to mitigate risk of exposure keratopathy in ICU patients.
