Indian Journal of Critical Care Medicine, Vol. 10, No. 1, January-March, 2006, pp. 11-14
Eye care in ICU
S. Sivasankar, S. Jasper*, S. Simon*, P. Jacob*, G. John, R. Raju*
From:Departments of Medical ICU and *Ophthalmology, Christian Medical College and Hospital, Vellore, Tamil Nadu - 632004, India
Correspondence Address:Dr. George John, Department of Medical ICU, Christian Medical College and Hospital, Vellore, Tamil Nadu - 632004, India. E-mail: firstname.lastname@example.org
Code Number: cm06001
Context: Patients in intensive care units have impaired ocular protective mechanisms, resulting in a high risk of developing eye complications. Various eye care protocols are being used, but none is proven to be absolutely effective.
Keywords: Exposure keratopathy, Intensive care patients.
Microbial keratitis is a severe complication of corneal exposure in critically ill patients. A variety of eye care protocols are being used, to prevent exposure keratopathy in intensive care patients and there is no clear consensus defining the most effective form of eye protection. A recent report from the United Kingdom revealed that 75% of the Intensive Care Units (ICU) used polyacrylamide gel for eye care, while 25% used ocular lubricants. Other commonly used methods include, placing a securing tape in a horizontal position over the closed eye lids and creating a moisture chamber to prevent corneal dryness.
We carried out a prospective comparative trial to compare the efficacy of using a combination of ocular lubricants and placing a securing tape (Open chamber method) and creating a moisture chamber by using swimming goggles and moistening eyelids with gauze soaked in sterile water every 12 hours (Closed chamber method), in preventing corneal epithelial breakdown in intensive care patients [Figure - 1][Figure - 2].
Use of closed chamber method offers better protection against exposure keratopathy in the intensive care patients, as compared to the use of a combination of ocular lubricants and securing tape over the eyelids.
Materials and Methods
All patients with a Glasgow coma scale score of ≤ to 10/15 admitted over a four month period to the Medical Intensive Care Unit of a large teaching hospital in South India, were included in the study. Patients were randomized into one of the treatment groups at admission. Those patients ≤ 18 years of age, spent less than 24 hours on the unit, or with primary ocular disease were excluded at the time of analysis.
A study proforma designed to include various medical and ophthalmologic details was used for each patient. Specific factors such use of muscle relaxants, Riker sedation score and duration of stay in ICU, were recorded. All patients were examined by an ophthalmologist within 24 hours of admission into the ICU and subsequently everyday, until the patient completed the study. A patient was declared to have completed the study if he regained spontaneous eye opening/ died / discharged from ICU, or developed corneal lesions.
A detailed eye examination was carried out to assess eyelid position, pupillary reaction, intraocular pressure and conjunctival and corneal changes. A portable slit lamp and Perkins′s tonometer were used for bedside evaluation. The cornea was examined for erosions, by instillation of 1% Fluorescein drops. The grading of eyelid position, corneal changes (grades 1-6) and conjunctival oedema (grades 1-3) are given in [Table - 1].
A total of 146 patients were recruited. Twenty two patients were excluded at the time of analysis. Analysis was carried out for 122 eyes (61 patients) randomized into the open chamber group and 126 eyes (63 patients) into the closed chamber group. The mean age of the patients was 39.2 years and 42.3 years in the open chamber and closed chamber group, respectively.
Incomplete lid closure was noticed in 74 (30%) of the 248 eyes analyzed. The extent of ocular surface exposure of the eyes analyzed in both the groups is given in [Table - 2].
A total of 27 patients (21%) had exposure keratopathy. Twenty two patients (81.5%) had bilateral lesions, while five (18.5%) had unilateral lesions. Hence, exposure keratopathy was noted in 49 (19.8%) of the 248 eyes in the study. Thirty nine (32%) eyes in open chamber group and ten (8%) eyes in closed chamber group had evidence of corneal disease, showing a significant difference between the two groups ( P -value of 0.001 and chi-square of 22.5). The extent of exposure keratopathy in both these groups is given in [Table - 3]. Most corneal lesions developed within 48 hours of admission in both groups; 37 of 39 (95%) in open chamber and eight of ten (80%) in closed chamber group. Exposure keratopathy was more severe in the open chamber group, than in the closed chamber group. Tarsorrhaphy was performed in one patient in the open chamber group who had unilateral grade 4 corneal lesions.
Grade 1 conjunctival oedema was noted in 32 eyes (22%) in the open chamber group and 36 (28%) in the closed chamber group. No significant difference was observed in the incidence of conjunctival oedema (chi-square = 0.085).
The other significant problems observed were lid abrasions and conjunctival abrasions in 15 (12%) eyes in open chamber group and oedema of the eyelids due to the pressure of the goggles over the globe in eight (6.5%) eyes, in the closed chamber group.
Analysis of the influence of specific factors on the development of keratopathy was carried out for all the 124 patients, irrespective of the eye care protocol implemented. It was found that incomplete lid closure and use of muscle relaxants were significantly associated with corneal disease ( P -values of 0.001 and 0.025 respectively). However, sedation score and mean duration of stay in ICU had no significant effect on the incidence of keratopathy.
All 34 eyes with incomplete lid closure at admission in the open chamber group developed exposure keratopathy, while only 11 (27.5%) of the 40 eyes in the closed chamber group showed evidence of the same. The protection against keratopathy in the presence of incomplete lid closure in the closed chamber group appears significant ( P -value = 0.001).
The ocular surface in healthy individuals is protected by natural defence mechanisms such as bactericidal effect of the tear film, blinking of eyelids and adequate lid closure. The tear film provides mechanical lubrication to wash away organisms and also contains antimicrobial substances such as immunoglobulins, lysozyme, lactoferrin, ceruloplasmin and complement components. Use of muscle relaxants and sedation in patients on ventilator contributes to inadequate lid closure by decreasing the tonic contraction of ocular muscles. Thus, inadequate protective mechanisms and constant exposure of the ocular surface to the environmental pathogens, put the ICU patients at high risk of developing exposure keratopathy. Eye care is therefore of paramount importance in ICU patients, to avoid easily preventable complications of the eye, as poor vision can have a devastating effect on the quality of life in those who recover.
Previous studies have reported that about 40% of patients develop exposure keratopathy during their stay in the ICU., Despite the use of a variety of eye care protocols, none has been proven to be absolutely effective and eye complications continue to be a significant problem in ICU patients.
Our study revealed that 39 (32%) out of 122 eyes developed exposure keratopathy with use of ocular lubricants and securing tape, while 10 (8%) out of 126 patients had evidence of the same, when a moisture chamber was created with use of swimming goggles and regular moistening of the eyelids with gauze soaked in sterile water. This reflects that use of swimming goggles is more effective in preventing exposure keratopathy. In a similar study, Cortese et al reported that a moisture chamber is more effective than lubricating drops, in preventing corneal epithelial breakdown. Moreover, patients in the open chamber had more severe corneal disease and one patient required tarsorrhaphy to facilitate corneal healing.
Conjunctival oedema termed as ventilator eye, occurred in 32 (22%) eyes in the open chamber group and 36 (28%) eyes in the closed chamber group. Moisture chamber did not seem to prevent the development of chemosis. However, it was technically more difficult to apply a securing tape over the eyelids when chemosis was present. Fifteen eyes (12%) in the open chamber had conjunctival abrasions, while the tape was being removed.
The pressure of the goggles over the eyelids caused significant lid oedema in eight eyes (6.5%). However, oedema subsided when the tension of the goggles was reduced.
In this study, we have observed that incomplete lid closure and use of muscle relaxants are the most important predictive factors for developing exposure keratopathy. However, it was observed that while all 34 eyes with incomplete lid closure developed corneal disease in the open chamber group, only 11 (27.5%) of 40 eyes in the closed chamber group showed evidence of the same. This suggests that a moisture chamber is better in preventing keratopathy, even in those patients with incomplete lid closure.
The main strength of our study lies in its prospective design, systematically comparing the two different practices. The results of our study clearly indicate that use of closed chamber method reduces the incidence of exposure keratopathy to 8%, compared to 32% with use of ocular lubricants and taping the eyelids. We, therefore, suggest the use of closed chamber method as regular eye care practice in the intensive care units for all sedated and semiconscious patients, to prevent exposure keratopathy. However, regular assessment of eye hygiene and a prompt ophthalmologic opinion obtained early in the event of any evidence of keratopathy, helps to minimize further complications. Further studies to assess the benefit of combined use of ocular lubricants and closed chamber method, are recommended.
Copyright 2006 - Indian Journal of Critical Care Medicine
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