Impact of Estimated Concentration of Propofol on Implicit Memory Formation

Impact of Target Controlled Infusion Estimated Concentration of Propofol on Implicit Memory Formation During Propofol-Remifentanil General Anaesthesia

Implicit memory formation and learning during general anaesthesia is a still debated question and no anesthetic regimen (ie intravenous anaesthesia vs inhalatory one) nor analgesic regimen (i.e. low or high opioids usage) has been identified for prevention.

With this study the investigators aim to investigate if, during Total Intravenous Anaesthesia with Target Controlled Infusion (TIVA-TCI) different concentrations of Propofol at loss of responsiveness, maintenance and return of responsiveness can have a role in implicit memory formation.

Study Overview

• Status: Not yet recruiting
• Conditions: General Anaesthesia; Implicit Memory

Detailed Description

Implicit memory formation and learning during general anaesthesia is a still debated question and no anesthetic regimen (ie intravenous anaesthesia vs inhalatory one) nor analgesic regimen (i.e. low or high opioids usage) has been identified for prevention.

With this study the investigators aim to investigate if, during Total Intravenous Anaesthesia with Target Controlled Infusion (TIVA-TCI) different concentrations of Propofol at loss of responsiveness (CeP RoR), maintenance (CePMA) and return of responSiveness (CeP RoR) can have a role in implicit memory formation.

20 most common italiaN words will be continuously presented to the anaesthetized patients from Loss of responsiveness to end of surgery.

CeP RoR, MA and LoR, as well as patient state index (PSi) from Sedline monitor for hypnosis level monitoring will be recorded.

Within 24 hours, a trained psychologist will be present the patients the Word Steam Recognition Test, Free Recall and Force Choice recognition task to asses the presence of implicit memory formation. A second group, who did not hear the words, will be investigated to assess the role of chance in the above-mentioned test.

• Study Type: Observational
• Enrollment (Estimated): 80

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Probability Sample

Study Population

Breast-Surgery women undergoing TIVA-TCI

Description

Inclusion Criteria:

• General anaesthesia with TIVA-TCI

Exclusion Criteria:

• ASA > III
• Benzodiazepines premedication
• Neurological/Psychiatric disease

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Cases; Patients who, during general anaesthesia, will hear the 20 words and will be tested form implicit memory formation.
Controls; Patients who, during general anaesthesia, will not hear the 20 words and will be tested form implicit memory formation to assess the role of chance on the tests adopted

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The role of Propofol Concentration at the loss of responsiveness on Implicit Memory formation	CeP at LOR will be compared between patients who exhibit or not implicit memory formation.	CeP will be recorded at Loss of responsiveness. Word Steam recognition, Free recall and Forced Choice Recognition Task will be performed within 12-24 hours after surgery. These 3 tests are analysed togheter to check for implicit memory formation.
The role of Propofol Concentration at the maintenance of anaesthesia on Implicit Memory formation	CeP at anaesthesia maintenance will be compared between patients who exhibit or not implicit memory formation.	CeP will be recorded during anaesthesia maintenance. Word Steam recognition, Free recall and Forced Choice Recognition Task will be performed within 12-24 hours after surgery. These 3 tests are analysed togheter to check for implicit memory formation.
The role of Propofol Concentration at the return of responsiveness on Implicit Memory formation	CeP at ROR will be compared between patients who exhibit or not implicit memory formation.	CeP will be recorded at Return of responsiveness. Word Steam recognition, Free recall and Forced Choice Recognition Task will be performed within 12-24 hours after surgery. These 3 tests are analysed togheter to check for implicit memory formation.

Collaborators and Investigators

• Sponsor: University of Padova

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2024
• Primary Completion (Estimated): October 31, 2024
• Study Completion (Estimated): November 15, 2024

Study Registration Dates

• First Submitted: July 1, 2024
• First Submitted That Met QC Criteria: July 9, 2024
• First Posted (Actual): July 12, 2024

Study Record Updates

• Last Update Posted (Actual): July 12, 2024
• Last Update Submitted That Met QC Criteria: July 9, 2024
• Last Verified: June 1, 2024

More Information

Terms related to this study

• Other Study ID Numbers: ImpliMAST

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No