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Vitrectomy is one of the most commonly performed surgeries in ophthalmology. Recent times have seen tremendous advancements in instrumentation and surgical techniques. One of the most important developments is the introduction of vitreous substitutes. This activity reviews the various types of vitreous substitutes, their properties, indications, the technique of administration, and the complications, as well as highlights the role of the interprofessional team in choosing and using the correct substitute for various vitreoretinal pathologies. Objectives: Summarise the various types of vitreous substitutes. Describe the mechanisms of action of various vitreous substitutes. Review the administration techniques and complications associated with various vitreous substitutes. Outline the method of monitoring patients who have received vitreous substitutes and the role of interprofessional collaboration to ensure best outcomes. Access free multiple choice questions on this topic.

There are no known acute toxicity syndromes associated with these vitreous substitutes. However, if high IOP is noted due to overfill, a partial removal may be needed: Gas: Although anterior chamber paracentesis may provide temporary relief, partial gas removal may be needed. A half water-filled syringe with plunger removed can be inserted in the vitreous through the par plana, and a few gas bubbles can be removed. SO: A single cannula can be inserted through the superior par plana, and SO can be partially removed passively.

The assisting team in the operating room should be sensitized towards the techniques of preservation, preparation, and use of the vitreous substitutes. All the substitutes should be appropriately labeled during storage as well as usage. It should be ensured that the correct gas concentration has been achieved before injecting. It is imperative to understand that a gas injection of incorrect concentration can lead to catastrophic outcomes. The gas or air-gas mixture should be used immediately after preparation as any air influx from the surroundings can cause inaccuracy in its concentration. Similarly, the liquid substitutes (PFCL, SO) can be easily confused with each other and viscoelastic and anesthetic agents. A wrong injection can similarly be disastrous for the eye. The assistant should be explained that the fluid infusion should not be switched on until the presence of the infusion cannula tip inside the vitreous cavity has been confirmed by the surgeon. The fluid infusion should not be stopped during the vitrectomy. Interprofessional collaboration plays a crucial role in ensuring the best visual outcomes. Optometrists and technicians help in documenting the best-corrected visual acuity and intraocular pressure. The pharmacist helps in dispensing the preoperative and postoperative medications. The nursing staff ensures compliance with therapy. Collaboration with anterior segment surgeons and glaucoma surgeons is needed to manage cataracts and glaucoma, respectively. Physicians should optimize systemic therapy so that the patient can undergo retinal surgery safely. The anesthetist ensures anesthesia and analgesia during surgery. If intravitreal gas is planned, anesthesia with nitrous oxide should be avoided or stopped at least 15 to 20 minutes before the intravitreal gas injection to avoid dangerously high levels of intraocular pressure.[58][59]