Conscious Sedation for Cataract Operations Under Topical Anaesthesia

Study Overview
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Brief Summary
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Topical anaesthesia of the eye for ophthalmologic procedures avoids pain and discomfort of local anaesthetic injection in the peribulbar or retrobulbar block so that patient comfortability is achieved. Sedation during topical anaesthesia of the eye is mostly required to achieve anxiolysis, amnesia and keeping the patient calm all through the procedure. In the present study, the investigators will investigate the effect of nalbuphine/dexmedetomidine versus nalbuphine/propofol on the sedation as a primary outcome, intra-operative, postoperative analgesia, vital signs, patient and surgeon satisfaction and side effects as secondary outcomes

Detailed Description
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In both groups, the patients will receive i.v. nalbuphine 50 μg/kg. Patients in group D, will receive an i.v. loading dose of dexmedetomidine 1 μg/kg over 10 min followed by a maintenance infusion of 0.5 μg/kg/h. Patients in group P, will receive a bolus i.v. dose of propofol 0.5 mg/kg followed by an infusion started at 0.025 mg/kg/min .If sedation score was <3, rescue sedation with boluses of midazolam 0.01 mg/kg will be given. If the patient complained of pain (Numerical verbal pain rating scale ≥3) during the surgery, i.v. fentanyl 50 μg will be given as an intra-operative rescue analgesic and the surgeon will be instructed to use additional topical local anaesthetic eye drops if appropriate. After the completion of surgery, all infusions will be stopped, and the patients will be shifted to the postanaesthetic care unit (PACU) to be monitored for 2 hours before discharge.

Official Title
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Nalbuphine/Dexmedetomidine Versus Nalbuphine/Propofol Conscious Sedation for Cataract Extraction Under Topical Anaesthesia: A Double-Blind Randomized Trial

Conditions
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Conscious Sedation

Intervention / Treatment
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* Drug: Nalbuphine
* Drug: Propofol
* Drug: Dexmedetomidine
* Drug: Benoxinate Hydrochloride 0.4% Eye Drops


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Both genders, 20 and 65 years, American Society of Anesthesiologists (ASA) physical status I and II, Scheduled for cataract extraction surgery under topical anaesthesia. Exclusion Criteria: Known allergy to local anaesthetics, Allergy to study drugs, Second or third-degree heart block, Alcohol or drug abuse Morbid obesity, pregnant and lactating females, Patients with severe cardiac, renal and hepatic disorders.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group P<br>nalbuphine/propofol group | Drug: Nalbuphine<br>* i.v. nalbuphine bolus of 50 μg/kg.<br>* Other names: Nalbuphine bolus;Drug: Propofol<br>* A bolus i.v. dose of propofol 0.5 mg/kg followed by an infusion of 0.025 mg/kg/min<br>* Other names: propofol infusion;Drug: Benoxinate Hydrochloride 0.4% Eye Drops<br>* Benoxinate hydrochloride 0.4% eye drops instilled twice, 5 minutes apart.<br>* Other names: Topical anaesthesia of the eye;|
| Active Comparator: Droup D<br>Nalbuphine/dexmedetomidine group | Drug: Nalbuphine<br>* i.v. nalbuphine bolus of 50 μg/kg.<br>* Other names: Nalbuphine bolus;Drug: Dexmedetomidine<br>* i.v. loading dose of dexmedetomidine 1 μg/kg over 10 min followed by a maintenance infusion of 0.5 μg/kg/h.<br>* Other names: Dexmedetomidine infusion;Drug: Benoxinate Hydrochloride 0.4% Eye Drops<br>* Benoxinate hydrochloride 0.4% eye drops instilled twice, 5 minutes apart.<br>* Other names: Topical anaesthesia of the eye;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sedation score | The degree of sedation assessed by Ramsay sedation score(1 = anxious, agitated, restless;2 = cooperative, oriented, tranquil; 3 = responds to commands only; 4 = brisk response to light glabellar tap or loud noise; 5 = sluggish response to light glabellar tap or loud noise; 6 = no response), score of (1) means inadequate sedation. Score (2 to 4) indicates acceptable sedation. Score (5) or (6) excessive sedation. | perioperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart rate | Heart rate in beats/minutes | perioperative | 
| Mean arterial blood pressure | Mean arterial blood pressure in mmHg | perioperative | 
| Oxygen saturation | Arterial oxygen saturation as a percentage of the total haemoglobin | perioperative | 
| Analgesia | Measured by Numerical Pain Rating scale where the patient verbally rates pain from 0 no pain to 10 worst imaginable pain | perioperative |