Impact of Estimated Concentration of Propofol on Implicit Memory Formation

Not yet recruiting

• Conditions: General Anaesthesia; Implicit Memory

• Registration Number: NCT06497855
• Lead Sponsor: University of Padova

Brief Summary

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.

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 Timeline

• Status Verified: 2024-06
• Study Start: 2024-07-01
• Study First Submitted: 2024-07-01
• Study First Submitted QC: 2024-07-09
• Last Update Submitted: 2024-07-09
• Study First Posted: 2024-07-12
• Last Update Posted: 2024-07-12
• Primary Completion: 2024-10-31
• Study Completion: 2024-11-15

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: Female
• Target Recruitment: 80

Inclusion Criteria

• General anaesthesia with TIVA-TCI

Exclusion Criteria

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

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
The role of Propofol Concentration at the return of responsiveness on 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.	CeP at ROR will be compared between patients who exhibit or not implicit memory formation.
The role of Propofol Concentration at the loss of responsiveness on 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.	CeP at LOR will be compared between patients who exhibit or not implicit memory formation.
The role of Propofol Concentration at the maintenance of anaesthesia on 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.	CeP at anaesthesia maintenance will be compared between patients who exhibit or not implicit memory formation.