Shared eye drop bottles: Danger in making every drop count

From the Nov. 4 , 1998 issue

PROBLEM: Multiple eye medications are used when patients undergo cataract surgery. Yet, facilities receive little or no reimbursement for these medications from prospective payment systems or other insurers that consider these medications to be outpatient prescriptions. As such, it has become practice in some facilities for eye drop containers to be shared among patients. Communal eye drops may be used in both outpatient and inpatient areas to prevent waste, control cost, and for convenience to avoid constant entry into automated dispensing cabinets and inventory replacement. Some health professionals are concerned that communal containers might be contaminated, which could risk patient infection.

There are few large-scale studies that directly examine the safety of sharing eye drop containers. However, existing literature indicates that ocular cross-contamination will occur. Preservatives ordinarily prevent bacterial growth in the solution. Still, bacteria may be present on bottle top inner surfaces or container grooves and tips. Hovding et al¹ examined 638 in-use containers. Bacteria were recovered from 82 (12.9%) bottles when dripped. Clinically and microbiologically significant growth was found in 12 cases (1.9%). Serratia keratitis has been transmitted by a contaminated eyedropper,² and contaminated eye drops have caused Pseudomonas aeruginosa corneoscleritis.³ Additional studies confirm that in-use container contamination occurred, and that serious eye infections can be transmitted from such containers.^4-8 These studies also refute the belief that doctors, nurses and patients will always apply eye drops properly, without touch contamination. The likelihood of infection may increase for those with compromised immune systems or wounds such as penetrating eye injury or recent surgery. Yet it is doubtful that these patient conditions will always be screened effectively to prevent the use of communal drops. Assurance of proper eye solution storage and disposal upon expiration is also difficult.

Medication errors, such as wrong drug and wrong concentration are more likely with communal drops since patients' names are not on the container label. Recently, the American Academy of Ophthalmology convinced leading ophthalmic manufacturers to color-code their ocular medications by therapeutic category. Unfortunately, this has led to mix-ups within each category because many distinctly different items now have identical color schemes, logos, fonts or other characteristics that make product differentiation difficult (see related story in Safety Briefs and ISMP Medication Safety Alert! Jan 28, 1998). Thus, a single dispensing error could result in a series of errors involving numerous patients.

SAFE PRACTICE RECOMMENDATION: Using communal eye drops increases the risk of infection and medication error. In fact, the CDC considers tears an infectious body fluid and recommends that staff use personal protective equipment whenever the potential for exposure exists. Also, labeling on some ophthalmic products suggests that medications should not be shared among patients. As such, eye drops should not be shared among patients. In human terms, the cost of an eye infection might be blindness. In financial terms, the cost of treating or litigating even a single eye infection from cross-contamination could easily eliminate the savings from communal eye drops generated over several years. For institutional use, purchase eye medications in the smallest package size possible. Unit-of-use packaging is available for many commonly used eye medications. Still, manufacturers may not price these products attractively to promote their use. Alternatively, it may be possible for patients to fill prescriptions for eye medications prior to surgery, and bring them in for the procedure.

. References: 1. Hovding G, Sjursen H. Bacterial contamination of drops and dropper tips of in-use multidose eye drop bottles. Acta Ophthalmologica 1982;60:213-222; 2. Templeton WC, Eiferman RA, Snyder JW et al. Serratia keratitis transmitted by contaminated eyedroppers Am J Ophthalmol 1982; 93:728-6; 3. Alfonso E, Kenyon KR, Ormerod LD et al. Pseudomonas corneoscleritis. Am J Ophthalmol 1987;103:90-8; 4. Schein OD, Hibberd PL, Starck T et al. Microbial contamination of in-use ocular medications. Arch Ophthalmol 1992;110:82-5; 5. Clark PJ, Ong B, Stanley CB. Contamination of diagnostic ophthalmic solutions in primary eye care settings.Mil Med 1997;162:501-6; 6. Raynaud C, Laveran H, Rigal D et al. Bacterial contamination of eyedrops in clinical use. J Fr Ophthalmol 1997;20:17-24; 7. MMWR 1996; Jun 14;45(23):491-4. Outbreaks of postoperative bacterial endophthalmitis caused by intrinsically contaminated ophthalmic solutions--Thailand, 1992, and Canada, 1993; 8. Geyer O, Bottone EJ, Podos SM, Schumer RA, Asbell PA. Microbial contamination of medications used to treat glaucoma. Br J Ophthalmol 1995; 79:376-9.