Abstract
Purpose :
Intervention after chemical ocular injury includes prompt irrigation to restore physiologic pH. The purpose of this laboratory study was to assess the effectiveness of a novel eyelid retractor and irrigation device after simulated chemical injury in a porcine model.
Methods :
A total of 18 porcine eyes were included in this study. The alkali chemical injury group included eyes receiving 1.0mL of 10.0% sodium hypochlorite solution with a pH of 13.0 (n=10). The acid injury group included eyes receiving 1.0mL of 10.0% acetic acid solution with a pH of 2.5 (n=8). The solution was left in each eye for one minute and the periocular tissue was moved in a blinking motion ten times. To assess standard chemical injury management, eyes in the acid (n=4) and alkali (n=5) injury groups were directly rinsed with saline via 10cc syringe. This process was performed three times total. To assess experimental chemical injury management, eyes in the acid (n=4) and alkali (n=5) injury groups were rinsed with saline using a novel eyelid retractor with irrigation ports connected to a 10cc syringe. Using the device to retract the eyelid, the syringe plunger was depressed to allow simultaneous irrigation. This process was performed three times total. One minute after each rinse, pH was measured using a digital pH meter. Statistical significance of post-rinse mean pH between management conditions was compared using unpaired t-tests (p<.05).
Results :
A single pH measurement of 7.2 was collected from one porcine eye to establish an approximate physiologic surface pH prior to chemical exposure. In eyes exposed to sodium hypochlorite, there was a significant difference in mean post-rinse pH (p=.02) using the novel device (9.0±0.19) compared with using a syringe alone (9.5±0.23). In eyes exposed to acetic acid, there was also a significant difference in mean post-rinse pH (p<.001) using the novel device (4.4±0.14) compared with using a syringe alone (3.8±0.10).
Conclusions :
A syringe is often the only available frontline irrigation device after chemical exposure and does not facilitate eyelid retraction to irrigate the ocular fornix and palpebral conjunctiva resulting in residual chemicals on the ocular surface. The results of this study suggest use of a modified eyelid retractor and irrigation device more effectively neutralized pH after simulated chemical injuries compared to current irrigation practices.
This is a 2021 ARVO Annual Meeting abstract.