Did your patient get a splash of bleach in his eye while doing laundry?
If you called Poison Control they probably asked you what the pH of the eye is and after your failed search through the ED for eye pH paper, what can you use?
Urine dipsticks! Gently tap the pH portion over a patient's eye and check the corresponding pH on the dipstick strip bottle. Just remember that a urine dipstick can only detect a pH range of 5-8.5, so you may end up needing the eye pH paper for the full range of 1-14.
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