For patients with eye surgery and shorter surgery, sedation is a well-established method in preserved consciousness and has been successfully used for several years. We have also developed and published a valid protocol (1).

Remifentanil is used in intravenous infusion for sedation and anxiolysis. Remifentanil is a descriptive analgesic, which also works partially anxiolytically. In eye surgery, it is important that the patient cooperates during the operation and should not be ashamed, as injury to the eye could occur, because the vitrectomes are performed with a fine intraocular endoscopic technique, in which the operator inserts his instruments through the whiteness into the eye. For this reason, we have not yet added additional sedatives (for example, midazolam), which is very unpredictable as regards sedation. Remifentanil is also very unpredictable and it is very difficult to control it during the operation so that the patient is saturated with satisfaction.

Lately, dexmedetomidine has been successfully used in sedation for other areas of surgery (eg neurosurgery, maxillofacial surgery, ORL). It is a safe, proven, active substance with alpha 2 agonistic effect, which has not yet been used in the field of ocular surgery and has not yet published articles in this field. The substance is very suitable because it works mildly sedative and at the same time analgesic.

For patients with eye surgery and shorter surgery, sedation is a well-established method in preserved consciousness and has been successfully used for several years. We have also developed and published a valid protocol (1).

Remifentanil is currently used for intravenous infusion for analgesia and anxiolysis. Remifentanil is an opioid analgesic, which also works partially anxiolytically. It has been studied in detail for postnatal analgesia (2). In eye surgery, it is important that the patient cooperates during the operation and should not be ashamed, as injury to the eye could occur, because the vitrectomes are performed with a fine intraocular endoscopic technique, in which the operator inserts his instruments through the whiteness into the eye. For this reason, we have not yet added additional sedatives (for example, midazolam), which is very unpredictable and a rapidly shallow sedation can pass into the deeper. Remifentanil is also very unpredictable and it is very difficult to control it during the operation, so that the patient is satisfactorily analgesized at all times, but still co-operable.

Recently, dexmedetomidine (3-5) has been successfully used in other areas of surgery (eg neurosurgery, maxillofacial surgery, ORL) and intensive sedation therapies. It is a safe, proven, active substance with alpha 2 agonistic effect, which has not yet been used in the field of ocular surgery and has not yet published articles in this field. The substance is very suitable because it works mildly sedative and at the same time analgesic (3).

Dexmedetomidine is predominantly administered intravenously, and intranasal administration (6-8) has also been established in pediatric patients.

We decided to use intranasal use because it is simple, safe and suitable for such treatments because intravenous dexmedetomidine could not be administered because it should be given enough time before surgery (at least 40 min) because otherwise the appropriate effect . Patients for such operations will enter the operating room directly from the departments on foot and dexmedetomidine could not be started earlier, as it is not possible to provide adequate control in the department. A sedentary patient would also not be able to walk into an operational one, which would greatly complicate and also increase logistics.

The study is applicable, as it will provide objective indicators, which type of sedation is most effective and safe for vitreoretinal interventions.

Inclusion Criteria: patients who will be operated on the eye (vitreoretinal interventions) patients with ASA status 1-3

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Exclusion Criteria:

• patients who will not want to be operated in the sedation but in general anesthesia
• poor general condition (ASA> 3)
• with severe cardiac disease (NYHA> 3)
• with severe pulmonary obstructive disease (FEV1 <40%)
• neurological diseases
• psychiatric patients
• patients receiving regular psychotropic treatment