Ignite Creation Date:
2024-05-05 @ 6:35 PM
Last Modification Date:
2024-10-26 @ 9:35 AM
Study NCT ID:
NCT00513032
Status:
COMPLETED
Last Update Posted:
2007-08-08
First Post:
2007-08-07
Brief Title:
Interaction Between Anaesthetics and Methylene Blue
Sponsor:
University Hospital Geneva
Organization:
University Hospital Geneva
Study Overview
Official Title:
Effects of Methylene Blue on Propofol Requirement During Anaesthesia Induction and Surgery
Status:
COMPLETED
Status Verified Date:
2007-08
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
We hypothesized that pre-treatment with methylene blue could potentiate the effects of general anaesthetic agents in patients undergoing parathyroidectomy
Detailed Description:
Sample and study design The local ethics committee granted approval for this study and informed written consent will be obtained from all participants We will study ASA grade I or II patients aged between 45 and 73 years who were free from cardiovascular and pulmonary diseases Patients with psychiatric disorders or drug abuse as well as those weighing 20 more or less than their ideal body weight will all be excluded
The interventional group will consist of 11 patients scheduled for elective parathyroidectomy who will receive MB infusion 5mgkg-1 in 250 ml 5 glucose-saline approximately 60 min before anaesthesia induction A further 11 patients scheduled for unilateral thyroid lobectomy without MB pre-treatment will be recruited as controls They will present with normal thyroid tests and will carefully be selected in an attempt to match the intervention group on the basis of age weight and sex Both types of surgical procedures will be performed by the same surgical team
Anaesthesia and surgery All patients will be premedicated with oral midazolam 75 mg and they will receive a loading dose of lactate-ringer solution 5 mlkg-1 intravenously after arrival in the operating theatre The standard anaesthetic monitoring will comprise non-invasive blood pressure ECG pulsed oxygen saturation and end-tidal carbon dioxide Processed EEG parameters will be acquired with a BIS monitor using surface electrodes with impedance maintained at less than 5kΩ to ensure adequate signal quality Raw EEG data from two channels F7-CZ and F8-CZ will be processed by company proprietary software and the BIS values calculated for each 4-sec epoch will be continuously displayed along with the trend line
Propofol will be infused using a commercially available TCI system loaded with Schneiders 3-compartment pharmacokinetic model wherein the individual patients age height and weight will be programmed The target effect-site concentration of propofol will be computed to yield a time to peak effect of 16 min which has been confirmed clinically
During anaesthesia induction the patients will breath an air-oxygen mixture through a face mask The target effect-site concentration of propofol will first be set at 05 ngml-1 and it will be increased by 02 ngml-1 every 2 min until the clinical endpoint will be achieved loss of consciousness and unresponsiveness Then ventilation will be assisted manually and the trachea will be intubated after the intravenous administration of fentanyl 100 mcg and rocuronium 07 mgkg-1
During anaesthesia maintenance the effect-site concentration of propofol will be targeted to achieve BIS values between 30 and 60 Additional fentanyl rocuronium or vasopressor agents ephedrine will be given at the discretion of the attending anaesthetist
Measurements When each patient will be comfortable on the operating table baseline measurements of BIS mean arterial pressure MAP heart rate HR and pulsed oxygen saturation SpO2 will be taken
During propofol induction BIS values MAP HR and SpO2 will be recorded every 1-min and the Observers Assessment of AlertnessSedation OAAS rating scale will be recorded after each equilibration period score 5awake and responds readily to name spoken in normal tone 4 lethargic response to name in normal tone 3response only after name is called loudly andor repeatedly 2 response only after name is called loudly and after mild shaking 1 dose not respond when name is called and after mild shaking
During surgery and anaesthesia maintenance BIS values and the effect-site concentration of propofol will be recorded each 5-min
Other recorded data will include the doses of propofol required for anaesthesia induction and maintenance the total amount of vasopressor and the time until anaesthesia emergence and readiness for tracheal extubation
Statistics Assuming that MB pre-treatment would reduce the requirement of propofol by 25 power analysis with alpha 005 beta 08 shows that we would need to study at least 10 patients in each group The computer program SAS 80 for Windows will be used for all data analyses Parametric data will be analysed by two-way ANOVA Unpaired Student t-tests Chi-squared tests and Fishers exact probability tests will be used as appropriate for comparison between groups All values are expressed as mean M standard deviation SD and statistical significance will be accepted at p 005
The interventional group will consist of 11 patients scheduled for elective parathyroidectomy who will receive MB infusion 5mgkg-1 in 250 ml 5 glucose-saline approximately 60 min before anaesthesia induction A further 11 patients scheduled for unilateral thyroid lobectomy without MB pre-treatment will be recruited as controls They will present with normal thyroid tests and will carefully be selected in an attempt to match the intervention group on the basis of age weight and sex Both types of surgical procedures will be performed by the same surgical team
Anaesthesia and surgery All patients will be premedicated with oral midazolam 75 mg and they will receive a loading dose of lactate-ringer solution 5 mlkg-1 intravenously after arrival in the operating theatre The standard anaesthetic monitoring will comprise non-invasive blood pressure ECG pulsed oxygen saturation and end-tidal carbon dioxide Processed EEG parameters will be acquired with a BIS monitor using surface electrodes with impedance maintained at less than 5kΩ to ensure adequate signal quality Raw EEG data from two channels F7-CZ and F8-CZ will be processed by company proprietary software and the BIS values calculated for each 4-sec epoch will be continuously displayed along with the trend line
Propofol will be infused using a commercially available TCI system loaded with Schneiders 3-compartment pharmacokinetic model wherein the individual patients age height and weight will be programmed The target effect-site concentration of propofol will be computed to yield a time to peak effect of 16 min which has been confirmed clinically
During anaesthesia induction the patients will breath an air-oxygen mixture through a face mask The target effect-site concentration of propofol will first be set at 05 ngml-1 and it will be increased by 02 ngml-1 every 2 min until the clinical endpoint will be achieved loss of consciousness and unresponsiveness Then ventilation will be assisted manually and the trachea will be intubated after the intravenous administration of fentanyl 100 mcg and rocuronium 07 mgkg-1
During anaesthesia maintenance the effect-site concentration of propofol will be targeted to achieve BIS values between 30 and 60 Additional fentanyl rocuronium or vasopressor agents ephedrine will be given at the discretion of the attending anaesthetist
Measurements When each patient will be comfortable on the operating table baseline measurements of BIS mean arterial pressure MAP heart rate HR and pulsed oxygen saturation SpO2 will be taken
During propofol induction BIS values MAP HR and SpO2 will be recorded every 1-min and the Observers Assessment of AlertnessSedation OAAS rating scale will be recorded after each equilibration period score 5awake and responds readily to name spoken in normal tone 4 lethargic response to name in normal tone 3response only after name is called loudly andor repeatedly 2 response only after name is called loudly and after mild shaking 1 dose not respond when name is called and after mild shaking
During surgery and anaesthesia maintenance BIS values and the effect-site concentration of propofol will be recorded each 5-min
Other recorded data will include the doses of propofol required for anaesthesia induction and maintenance the total amount of vasopressor and the time until anaesthesia emergence and readiness for tracheal extubation
Statistics Assuming that MB pre-treatment would reduce the requirement of propofol by 25 power analysis with alpha 005 beta 08 shows that we would need to study at least 10 patients in each group The computer program SAS 80 for Windows will be used for all data analyses Parametric data will be analysed by two-way ANOVA Unpaired Student t-tests Chi-squared tests and Fishers exact probability tests will be used as appropriate for comparison between groups All values are expressed as mean M standard deviation SD and statistical significance will be accepted at p 005
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None