Abstract
Purpose::
In observational studies, up to 40% of patients in intensive care units (ICU) develop exposure keratopathy. Protocols have been developed to prevent corneal damage from exposure, but there is no widely accepted standard of care. Two of the best-studied methods are moisture chambers (e.g. polyethylene film) and lubricating ointments. The purpose of this study is to analyze the best evidence available in order to compare methods of preventing ocular surface disease in ICU patients.
Methods::
Randomized controlled trials comparing methods of eye care for patients in intensive care units were identified by electronic searches of the MEDLINE database from 1966 to 2006, EMBASE, and Google Scholar. Search terms included ophthalmology, eye diseases, cornea, eye, intensive care units, critical care and randomized control trial. Bibliographies of retrieved articles were searched for further studies. Standard textbooks in ophthalmology and critical care medicine were also searched for additional trials. The search strategy revealed seven trials, of which three were suitable for evaluation by meta-analysis. The random effects model was used to combine results from individual trials and calculate estimates of the benefits associated with therapy.
Results::
The three randomized trials enrolled a total of 294 patients. Meta-analysis of these studies showed that rates of exposure keratopathy are significantly lower when moisture chambers are used to protect the eye compared to lubricating ointments. Eight of 113 patients (7.1%) in the moisture chamber group versus 32 of 151 patients (21.2%) in the lubrication group developed exposure keratopathy, with a summary odds ratio of 0.208 (95% CI 0.090-0.479, P<0.001). The heterogeneity among the results of the randomized controlled trials was not statistically significant (P=0.666).
Conclusions::
Meta-analysis showed that moisture chambers are significantly better than lubricating ointments at preventing ICU exposure keratopathy in ICU patients. ICU staff should be educated about the value of moisture chambers in protecting the eyes of their patients.
Keywords: cornea: clinical science • keratitis