How should a rat’s eyes be rinsed? - briefly
Rinse the rat’s ocular surface with sterile isotonic saline applied via a gentle pipette or bulb syringe, directing the flow from the inner to the outer canthus to prevent tear‑duct contamination. Perform the procedure under mild anesthesia and repeat as necessary to remove debris.
How should a rat’s eyes be rinsed? - in detail
Proper ocular irrigation in laboratory rats requires sterile technique, gentle handling, and precise fluid delivery. The goal is to remove debris, irritants, or chemical agents from the corneal and conjunctival surfaces while minimizing trauma.
Materials
- Sterile isotonic saline solution (0.9 % NaCl) at room temperature
- Micropipette or 1 mL syringe equipped with a blunt‑ended needle or catheter
- Sterile cotton swabs or gauze pads
- Disposable gloves and protective eyewear
- Anesthetic agent appropriate for rodents (e.g., isoflurane)
- Optional: small eye speculum to keep lids open
Preparation
- Place the animal in a restraining device that permits access to the head while limiting movement.
- Induce and maintain a surgical plane of anesthesia; confirm lack of blink reflex.
- Position the rat on a warmed surface, head tilted slightly backward to expose the ocular region.
Irrigation procedure
- Apply a sterile cotton swab to gently retract the upper and lower eyelids, creating a clear field.
- Using the micropipette, deliver 0.5–1 mL of saline onto the ocular surface in a continuous stream, directing the flow from the lateral canthus toward the medial canthus to avoid corneal contact with the delivery tip.
- Allow the fluid to cascade over the cornea and conjunctiva for 10–15 seconds, ensuring complete coverage.
- If residual material remains, repeat the flush with an additional 0.2–0.5 mL of solution.
- After the final rinse, blot excess fluid with a sterile gauze pad, taking care not to rub the cornea.
Post‑irrigation care
- Observe the animal for at least 10 minutes; verify normal blinking and absence of discharge.
- If irritation persists, apply a thin layer of ophthalmic ointment approved for rodents.
- Document the volume of solution used, duration of exposure, and any observed abnormalities.
Adherence to these steps ensures effective removal of contaminants from the rat’s eyes while preserving corneal integrity and preventing secondary infection.