Reattachment of the retina requires intraocular gas

Reattachment of the retina requires intraocular gas. What are the different types of gases that can be used, and what are the anesthetic implications of their use?

The surgeon may use intraocular air, sulfurhexafluo-ride (SF₆), octafluorocyclobutane (C₄F₈), or perfluoro-propane (C₃F₈). Since these gases are mixed with air in concentrations that normally do not expand, they will expand in volume with the coincident use of nitrous oxide (N₂O). If the procedure is performed under gen-eral anesthesia, N₂O should be discontinued at least 10–15 minutes prior to intraocular gas injection. In the case of C₃F₈ and SF₆, N₂O is contraindicated for at least 30 days to prevent subsequent increases in intraocular pressure. Intraocular gases are resorbed very slowly. Occasionally, intraocular silicone is injected, which does not resorb.

Postoperatively, intraocular gas may be directed to a par-ticular portion of the retina by adjusting the patient’s position. Prone, lateral decubitus, and sitting are commonly prescribed positions. Such departures from standard postanesthetic nursing care mandate an awake, cooperative patient.

Regional anesthesia techniques are most compatible with these postoperative requirements.

Nausea and vomiting are not only frequent sequelae of anesthesia but may also indicate increased intraocular pressure secondary to overinflation with intraocular gas. Nausea and vomiting often follow scleral buckling without gas injection and may be reduced by administration of perioperative ketorolac to diminish traction and inflam-matory-related pain.