This document aims to provide advice and information for clinical staff who are involved in eye care in the ICU. It is primarily intended to help non-ophthalmic ICU staff to:
It concentrates primarily on the common problems of the eye surface but also touches on other less common conditions. As such, it should also be helpful to those ophthalmologists asked for advice about ICU patients.
The health of the front surface of the eye, particularly the cornea (the clear front window of the eye) depends on the ability to produce tears, to blink, and to close the eyes with rest or sleep. These can be impaired on the intensive care unit (ICU) whether by disease (e.g. facial oedema, reduced conscious level, peripheral or central neurological injury) or treatments (e.g. the drying effects of gas flows from CPAP or oxygen masks). In particular muscle relaxants reduce the tonic contraction of the orbicularis muscle around the eye which normally keeps the lids closed, and sedation reduces blink rate and impairs (and can eliminate) the blink reflex. Whatever the cause, those unable to close the eye for themselves, or in whom blinking rates are substantially reduced, are at increased risk of damage to the front of the eye, and this risk is higher in those mechanically ventilated, due to greater length of stay, use of sedative/paralysing drugs and the effects of positive pressure ventilation.