Screening for ocular surface disease in the intensive care unit

Ventilated patients in the intensive care unit (ICU) often develop exposure keratopathy. This predisposes to the development of bacterial keratitis, which in ICU is often bilateral, with a high risk of perforation. As regular examinations of all ventilated patients by ophthalmologists would be impractical, the purpose of this study was to assess whether ICU staff can screen reliably for keratopathy.

A prospective study was performed in a general adult ICU. Twice each week, two junior ICU doctors examined the lid position and ocular surface of all patients who had been continuously sedated for more than 24 h, using fluorescein and a pen torch with a blue filter. An ophthalmologist performed similar examinations using a portable slit lamp.

A total of 48 ocular examinations were performed in 18 patients. Exposure keratopathy was found by the ophthalmologist in 37.5% of examinations and by ICU doctors in 31.3% of examinations. ICU doctors had a sensitivity of 77.8% and a specificity of 96.7% in detecting keratopathy, when compared with the findings of the ophthalmologist. All cases missed by ICU doctors had punctate erosions of less than 5% of the corneal surface. Keratopathy was significantly commoner in patients with incomplete lid closure than in patients with closed lids (70.0 vs 28.9%; two-tailed Fisher's exact test P=0.027).

ICU staff can perform screening examinations for exposure keratopathy with reasonable sensitivity and specificity. Regular screening by ICU staff would facilitate appropriate treatment of exposure keratopathy and promote earlier identification of cases of keratitis.