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Trial registered on ANZCTR


Registration number
ACTRN12625000299404p
Ethics application status
Submitted, not yet approved
Date submitted
2/04/2025
Date registered
15/04/2025
Date last updated
22/06/2025
Date data sharing statement initially provided
15/04/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Plasma concentrations and outcomes of an optimised intraoperative lidocaine infusion regimen in patients with obesity
Scientific title
Plasma concentrations and outcomes of an optimised intraoperative lidocaine infusion regimen in patients with obesity during laparoscopic abdominal surgery
Secondary ID [1] 314068 0
None
Universal Trial Number (UTN)
Trial acronym
LIIDO: Lidocaine Intraoperative Infusion Dose Optimisation in obesity
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 336815 0
Condition category
Condition code
Diet and Nutrition 333310 333310 0 0
Obesity
Surgery 333311 333311 0 0
Other surgery
Anaesthesiology 333309 333309 0 0
Anaesthetics

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
An intravenous lidocaine infusion regimen will be administered in patients with BMI >30kg/m2 having elective laparoscopic abdominal surgery. A regimen dosed according to lean body weight of of 2mg/kg bolus over 20 minutes commencing prior to skin incision, followed by 3mg/kg/hour for 80 mins then reduced to 2mg/kg/hour until completion of the surgery will be delivered and documented by the treating anaesthetist.

Intravenous lignocaine infusions are widely regarded as a valuable adjunct to laparoscopic abdominal surgical procedures however their use in this population group, with the current level of evidence, is entirely dependant on anaesthetist preference. As such in some cases intravenous lignocaine infusions would be used regardless but in some cases they will be utilised specifically for the purposes of the study.
Intervention code [1] 330644 0
Treatment: Drugs
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 341052 0
Plasma GX concentrations (secondary active metabolite of lidocaine)
Timepoint [1] 341052 0
Baseline prior to infusion starting (T0); at the completion of the 20-minute loading dose (T20), 5 minutes after completion of loading dose (T25); then at 60, and 100 minutes (T60; T100) during the infusion. A sample will be taken at 180 minutes after the regimen is commenced (T180) (following reduction of the infusion rate). Samples will also be taken at the time of discontinuation of infusion (TE); and then 10, 60 and 180 minutes after discontinuation of the infusion (TE10, TE60, TE180). Final samples at 6 and 24 hours (TP6, TP24).
Primary outcome [2] 340887 0
Plasma lidocaine concentrations
Timepoint [2] 340887 0
Baseline prior to infusion starting (T0); at the completion of the 20-minute loading dose (T20), 5 minutes after completion of loading dose (T25); then at 60, and 100 minutes (T60; T100) during the infusion. A sample will be taken at 180 minutes after the regimen is commenced (T180) (following reduction of the infusion rate). Samples will also be taken at the time of discontinuation of infusion (TE); and then 10, 60 and 180 minutes after discontinuation of the infusion (TE10, TE60, TE180). Final samples at 6 and 24 hours (TP6, TP24).
Primary outcome [3] 340888 0
Plasma MEGX concentrations (primary active metabolite of lidocaine)
Timepoint [3] 340888 0
Baseline prior to infusion starting (T0); at the completion of the 20-minute loading dose (T20), 5 minutes after completion of loading dose (T25); then at 60, and 100 minutes (T60; T100) during the infusion. A sample will be taken at 180 minutes after the regimen is commenced (T180) (following reduction of the infusion rate). Samples will also be taken at the time of discontinuation of infusion (TE); and then 10, 60 and 180 minutes after discontinuation of the infusion (TE10, TE60, TE180). Final samples at 6 and 24 hours (TP6, TP24).
Secondary outcome [1] 445959 0
Post-operative nausea and vomiting (PONV)
Timepoint [1] 445959 0
PACU, 24 h
Secondary outcome [2] 445357 0
Feasibility of delivering standardised anaesthesia and lidocaine protocol
Timepoint [2] 445357 0
Intraoperative.
Secondary outcome [3] 445957 0
Pain assessment
Timepoint [3] 445957 0
In post-anaesthetic care unit (PACU), at 24h
Secondary outcome [4] 445958 0
Opioid use
Timepoint [4] 445958 0
Intraoperative, PACU, first 24 hours, 48 hours.
Secondary outcome [5] 445356 0
Intraoperative anaesthesia details
Timepoint [5] 445356 0
Intraoperative.
Secondary outcome [6] 445961 0
Respiratory complications (e.g. desaturation, aspiration, respiratory failure)
Timepoint [6] 445961 0
PACU, 24 hr
Secondary outcome [7] 445962 0
Bowel recovery and ileus
Timepoint [7] 445962 0
Post-operative
Secondary outcome [8] 445966 0
Hospital length of stay (days)
Timepoint [8] 445966 0
Post-operative
Secondary outcome [9] 445964 0
PACU length of stay (minutes)
Timepoint [9] 445964 0
In PACU
Secondary outcome [10] 445967 0
Adverse events (including suspected local anaesthetic toxicity)
Timepoint [10] 445967 0
Intraoperative, PACU, post-operative
Secondary outcome [11] 445960 0
Quality of recovery
Timepoint [11] 445960 0
At 24 hours

Eligibility
Key inclusion criteria
BMI greater than or equal to 30 kg/m2
Elective laparoscopic abdominal surgery, expected > 90 mins duration, positioned with one arm available for venous sampling
Informed consent
Minimum age
18 Years
Maximum age
90 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Known or suspected allergy or contraindication to lidocaine or other amide local anaesthetics, including patients with porphyria and methaemaglobinaemia
Acute or chronic renal disease (estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m2)
Acute or chronic liver disease (based on laboratory reference range values)
Congestive cardiac failure or cardiac conduction abnormalities (e.g. heart block, bundle branch block, prolonged QT interval, Wolf Parkinson White Syndrome, or channelopathy (e.g. Brugada Syndrome)
Pregnancy
History of seizure disorder

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Pharmacokinetics
Statistical methods / analysis
An open-label plasma pharmacokinetic study of an intraoperative intravenous lidocaine infusions regimen in patients with obesity. Detailed phamacokinetic analysis of the total and unbound lidocaine, MEGX and GX concentrations using existing validated liquid chromatography mass spectrometry methodology. Analysis of alpha-1-acid glycoprotein and influence on protein binding as well as analysis of covariates (e.g. BMI, albumin).

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
2/02/2026
Actual
Date of last participant enrolment
Anticipated
2/02/2027
Actual
Date of last data collection
Anticipated
2/08/2027
Actual
Sample size
Target
30
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment hospital [1] 27671 0
Royal Brisbane & Womens Hospital - Herston
Recruitment postcode(s) [1] 43846 0
4029 - Herston

Funding & Sponsors
Funding source category [1] 318574 0
Hospital
Name [1] 318574 0
Royal Brisbane and Women's Hospital
Country [1] 318574 0
Australia
Primary sponsor type
Hospital
Name
Department of Anaesthesia Royal Brisbane and Women's Hospital
Address
Country
Australia
Secondary sponsor category [1] 320973 0
None
Name [1] 320973 0
Address [1] 320973 0
Country [1] 320973 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 317174 0
Metro North Health Human Research Ethics Committee A
Ethics committee address [1] 317174 0
Ethics committee country [1] 317174 0
Australia
Date submitted for ethics approval [1] 317174 0
05/06/2025
Approval date [1] 317174 0
Ethics approval number [1] 317174 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 140246 0
Dr Angela Tognolini
Address 140246 0
RBWH Anaesthetic Department Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Queensland 4029
Country 140246 0
Australia
Phone 140246 0
+61 7 36467154
Fax 140246 0
Email 140246 0
[email protected]
Contact person for public queries
Name 140247 0
Ms Christine Woods
Address 140247 0
RBWH Anaesthetic Department Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Queensland 4029
Country 140247 0
Australia
Phone 140247 0
+61 7 36467154
Fax 140247 0
Email 140247 0
[email protected]
Contact person for scientific queries
Name 140248 0
Angela Tognolini
Address 140248 0
RBWH Anaesthetic Department Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Queensland 4029
Country 140248 0
Australia
Phone 140248 0
+61 7 36467154
Fax 140248 0
Email 140248 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No
No IPD sharing reason/comment: This is a pharmacokinetic study for lidocaine infusions in the obese population as such the collected data is deidentified and pooled making each individual patient's data on its own irrelevant to the overall outcome.



What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.