Sodium hyaluronate eye drops improve tear film in anesthetized cats

Abstract

OBJECTIVES: This study aimed to evaluate the effect of 0.15% sodium hyaluronate (SH) on tear film breakup time (TFBT) in healthy anesthetized cats. PROCEDURES: Forty cats undergoing elective surgery were enrolled. TFBT was assessed before anesthesia to obtain baseline values. As a preanesthetic medication, cats received midazolam, tramadol, and cetamine combined in the same syringe. For anesthetic induction and maintenance, propofol and isoflurane were used. After a 15&#x2009;min stabilization period to achieve the surgical anesthetic plane, one eye was treated with one drop of SH, while the other eye received saline and served as a control. TFBT was measured at the end of the general anesthesia (T40) and 35 (T75) and 80&#x2009;min (T120) after the termination of the anesthesia. TFBT values were compared between the control and SH-treated eyes; both values were also compared with the baseline values (p&#x2009;<&#x2009;.05). RESULTS: In the control eyes, TFBT significantly decreased from baseline at all time points (p&#x2009;<&#x2009;.001), while in SH-treated eyes, TFBT significantly increased from baseline only at T40 (p&#x2009;<&#x2009;.0001). In SH-treated eyes, TFBT was significantly higher than that in the control eyes at all time points (p&#x2009;<&#x2009;.001). CONCLUSIONS: In healthy cats, TFBT decreases significantly after 40&#x2009;min of general anesthesia, and one drop of 0.15% sodium hyaluronate was able to maintain the stability of the tear film for up to 75&#x2009;min in treated eyes. However, the isolated effect of each drug used in our anesthetic protocol on TFBT should be executed in further studies.