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Cognitive Dysfunction After Cataract Surgery

The Effect of Ketamine and Dexmedetomidine on the Postoperative Cognitive Dysfunction After Cataract Surgery: Randomized Controlled Double-blinded Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04730596
Enrollment
90
Registered
2021-01-29
Start date
2021-02-01
Completion date
2021-04-15
Last updated
2021-04-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

POCD - Postoperative Cognitive Dysfunction

Keywords

Ketamine, Dexmedetomidine, cataract, Cognitive dysfunction

Brief summary

* Cataract surgery is commonly performed in elderly patients who are at high risk for developing postoperative cognitive dysfunction. Most cataract surgeries are performed under peribulbar or retrobulbar anesthesia, however, most of the patients require sedation to relieve the perioperative anxiety and induce amnesia. So, many sedative agents can be used especially benzodiazepines which may increase the risk of developing postoperative cognitive dysfunction. * Ketamine can be used as a sedative and analgesic agent in a dose of 0.25 -0.5 mg/kg with certain studies suggesting that it may decrease the risk of postoperative cognitive dysfunction. Similarly, dexmedetomidine can be used as a sedative and analgesic agent with the possibility of decreasing the incidence of postoperative cognitive dysfunction. * this controlled study will compare the effect of ketamine or dexmedetomidine on the POCD of patients undergoing cataract surgery.

Detailed description

* Postoperative cognitive dysfunction is a common postoperative complication in elderly patients. Despite the role of the risk of anesthesia and/or surgery in developing postoperative cognitive dysfunction, it can be developed even with surgeries performed under local or regional anesthesia. * Ageing is the most common risk factor for developing postoperative cognitive dysfunction that can affect memory and speech. Also, impaired vision may be another important risk factor. * Cataract surgeries can be considered the most common surgery performed in elderly patients. It is usually performed under local anesthesia (peribulbar, retrobulbar, or sub-tenon blocks), however, sedation is usually required to relieve the anxiety of the patients and induce amnesia. * there are many sedative agents that can be used with such patients, the most commonly used are benzodiazepines. However, benzodiazepines use may increase the incidence of postoperative cognitive dysfunction. * Ketamine, the dissociative anesthetic, acts mainly through inhibition of NMDA receptors that reduce the neuronal loss of the cortex. it may attenuate the postoperative cognitive dysfunction and induce neuroprotective effect through suppressing the inflammatory response and minimizing cerebral ischemia. * dexmedetomidine is a sedative and analgesic agent that have the advantage of minimal respiratory depression and can be used as a sedative agent in cataract surgery. Studied revealed that its sedative analgesic effect is not associated with changes in memory. * This randomized controlled double-blinded study will be carried upon 90 elderly patients undergoing cataract surgery under peribulbar anesthesia where they will be classified into 3 groups: - Group I (Placebo Group). Where the patients will receive normal saline as a placebo. Group II (Ketamine group). Where patients will receive ketamine in a dose of 0.3 mg/kg in physiological solution. Group III (Dexmedetomidine group). where patients will receive dexmedetomidine in a dose of 0.5 ug/kg in a physiological solution. -Primary outcome will be the incidence of POCD, the secondary outcomes will be the hemodynamic changes and the changes in the intraocular pressure.

Interventions

DRUGKetamine

Ketamine at a dose of 0.3 mg/kg dissolved in normal saline.

DRUGDexmedetomidine

Dexmedetomidine at a dose of 0.5 ug/kg dissolved in normal saline.

DRUGNormal saline

Normal saline in a labeled syringe

Sponsors

Magrabi Hospital - Doha
CollaboratorUNKNOWN
Tanta University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)

Masking description

* The patients will be blinded to their groups. * An anesthesia resident who will not participate in the study and have no the subsequent rule in it will help in the preparation of local anesthetic mixtures under strict aseptic precautions. * An assistant nurse who will be blinded to the study groups and will have no the subsequent rule in it will help in the collection of the data of measurements

Eligibility

Sex/Gender
ALL
Age
65 Years to 85 Years
Healthy volunteers
No

Inclusion criteria

* Patients aged more than 65 years presented for cataract surgery under peribulbar anesthesia.

Exclusion criteria

* Patients with a history of psychological disorders as psychosis, schizophrenia, nephropathy. * Patients with uncontrolled medical conditions as D.M and hypertension. * Known allergy to the used medications * patients with hepatic, renal, or heart failure * Patients receiving anti-psychotic or anti-depressant medications.

Design outcomes

Primary

MeasureTime frameDescription
The postoperative cognitive functionWithin the first 3 days after surgeryShort Portable Mental Status Questionnaire (SPMSQ) It is a score system that depends upon the number of errors in 10 questions asked to the patient where; - 0-2 errors: normal mental functioning 3-4 errors: mild cognitive impairment 5-7 errors: moderate cognitive impairment 8 or more errors: severe cognitive impairment Mental Status Questionnaire (SPMSQ) score will be used to assess the cognitive dysfunction

Secondary

MeasureTime frameDescription
Change in the intraocular pressureThroughout the whole intraoperative periodThe IOP will be measured before the peribulbar anesthesia, min, 5 min and 10 min after peribulbar injection, then immediately after surgery.

Countries

Egypt

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026