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Evaluation of Influencing Variables in Awakening Concentration and Concentration at Body Movements of Propofol TCI (Targeted Controlled Infusion) Targeted at the Effector Site

Completed
Conditions
Awareness, Anesthesia
Interventions
Drug: We do not modify the normale general anesthesia delivery. We note the concentration of propofol at the effector site of body movementsand awakening
Registration Number
NCT04129112
Lead Sponsor
University of Padova
Brief Summary

Age has been related to awakening propofol concentration at effector site of TCI, but not to the loss of consciousness concentration, neither to the concentration of body movements during surgery, that can be interpreted as a sign of light anesthesia and lead to awareness.

This study aims to determinate the incidence and the propofol TCI concentration at the effector site, in patients undergoing general anaesthesia without NBDs, of any patients body movements, defined as any spontaneous movements (but no reflex movements) during surgery.

Detailed Description

Target-Controlled-Infusion (TCI), estimating the effect-size concentration (Ce) of propofol and its elimination time with a computerized system, provides the anaesthesiologist useful information to guide anaesthesia.

Although the correlation between propofol at the effector site at loss of consciousness (Ce LOC) and age is still debated with contrasting results, the correlation between propofol at the effector site at return of consciousness (Ce ROC) and age is well established, and some authors suggested that, due also for age-related changes in both pharmacokinetics and pharmacodynamics of propofol, its dosage should be reduced in elderly patients.

Lowering propofol dosage however, can lead to an higher incidence of awareness during general anaesthesia, even if anaesthesia management is guided by consciousness monitors.

Awareness during anaesthesia has recently been defined not as a binary phenomenon, but as a graded spectra of states and, during general anaesthesia without using neuromuscular blocking drugs (NBDs), body movement on the operating table can be taken as an indication of increasing probability of consciousness or 'light' anaesthesia.

Hence, this study aims to evaluate the impact of age on the concentration at the effector site of propofol-remifentanil anaesthesia administered with TCI pump and without NBDs. Concnetration at the effector site of Propofol at the return of consciousness (CeP ROC) and at any clinical sign of superficialization such as body movements (CeP BM) will be considered.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
75
Inclusion Criteria
  • Patients undergoing general anesthesia with propofol and remifentanil delivered with TCI infusion pump
Exclusion Criteria
  • neurological or psychiatric or cerebrovascular diseases
  • renal insufficiency
  • patients unable to understand the information contained in the informed consent form,
  • patients with intraoperative hemodynamic instability or
  • patients who was delivered curare agents during anaesthesia

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Patients without body movementsWe do not modify the normale general anesthesia delivery. We note the concentration of propofol at the effector site of body movementsand awakeningPatient who, under general anesthesia without curare agents, during surgery has no body movements
Patients with body movementsWe do not modify the normale general anesthesia delivery. We note the concentration of propofol at the effector site of body movementsand awakeningPatient who, under general anesthesia without curare agents, during surgery has any body movements that are no reflexes movements
Primary Outcome Measures
NameTimeMethod
Incidence of body movements in patients undergoing surgery without curare agentsDuring surgery

We will note if patients have spontaneous movements during surgery, and calculate the incidence of the phenomenon.

Secondary Outcome Measures
NameTimeMethod
Concentration of propofol at body movementsPatients will be subjected to Sort Portable Mental Status Questionnaire (SPMSQ) before surgery. Other variables are collected during surgery

We will note the concentration at the effector site of propofol TCI during body movements and compare them to pre-operative and demographical variables (age, weight, height, American Society of Anaesthesiologist physical status classification system (ASA), number of previous general anaesthesia, years of schooling, Sort Portable Mental Status Questionnaire score) and intra-operative variables ( concentration at the effector site of remifentanil at ventilator maladjustment (CeR VM), mean Ce propofol and remifentanil target during maintenance, and maximum, mean and minimum State Entropy (SE) and Response Entropy (RE) values during maintenance).

Concentration of propofol at return of consciousnessPatients will be subjected to Sort Portable Mental Status Questionnaire (SPMSQ) before surgery. Other variables are collected during surgery

We will note the concentration at the effector site of propofol TCI at awakening and compare them to pre-operative and demographical variables (age, weight, height, American Society of Anaesthesiologist physical status classification system (ASA), number of previous general anaesthesia, years of schooling, Sort Portable Mental Status Questionnaire score) and intra-operative variables ( concentration at the effector site of remifentanil at ventilator maladjustement (CeR VM), mean Ce propofol and remifentanil target during maintenance, and maximum, mean and minimum SE and RE Entropy values during maintenance).

Trial Locations

Locations (1)

ULSS 2 Marca Trevigiana

🇮🇹

Treviso, Tv, Italy

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