Validation of a Pharmacokinetic Pharmacodynamic Model to Administer Propofol in Obese Patients

The purpose of this study is to validate an integrated pharmacokinetic-pharmacodynamic model to administer propofol in obese patients.

Our hypothesis is that pharmacokinetic and pharmacodynamic changes occur with increasing weight and that mathematical models to administer drugs in obese patients can be developed to accurately predict dose schemes in this population.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Obesity Body Weight Nutrition Disorders Nutritional and Metabolic Diseases Overnutrition Overweight Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

18 year–60 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Hospital Clinico Pontificia Universidad Catolica

Santiago, Santiago Metropolitan, Chile

About this study

Propofol is the most frequently used IV anesthetic today. Propofol TCI is commonly used for induction and maintenance of general anaesthesia in obese and non obese patients. However, current propofol PK models, used in TCI devices, were derived from studies that did not include obese patients. A controversial issue for propofol dose adjustment in this population has been the selection of an adequate size descriptor to scale PK parameters, as drug administration based on total body weight can result in overdose, and conversely, administration based on ideal body weight can result in a sub-therapeutic dose. In a previous study from our group, we developed a PK model capable of characterizing the influence of obesity on propofol disposition. The purpose of this study is to validate this model to administer propofol in obese patients.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

IMC > 35 kg m-2
Scheduled for laparoscopic bariatric surgery
ASA I-II patients
Between 18 and 60 yr of age.

Exclusion criteria

Patients with allergy to study drugs
Uncontrolled hypertension
Heart block greater than first degree
Take any drug acting in the central nervous system within 24 hrs before surgery.

Treatment and study plan

Propofol

Drug

General anesthesia will be induced administering propofol by effect site TCI system using our previously derived model, the target plasma concentration initially will be set at 4 mcg/ml. After loss of consciousness, rocuronium 0.6mg/kg, and remifentanil 0.2mcg/kg/min will be given to facilitate tracheal intubation. After intubation propofol target will be decreased to 3 for 10 minutes and then adapted to the needs of each patient to maintain stable BIS values between 40 and 50. At the end of surgery propofol infusion will be stopped, and patients will be transferred to the recovery unit extubated. Samples of 2.5 ml of arterial blood will be taken at 2, 5 and 10 min after every new target is set. Thereafter samples will be taken at 2, 5, 10, 15, 30, 60, 120 min after stopping drug infusion. Blood samples will be immediately centrifuged and then stored until analysis.

Primary outcomes

Validated pharmacokinetic-pharmacodynamic model of Propofol in Obese patients

Time frame: During the intraoperative period and until 120 min after stopping propofol infusion

Sponsors and collaborators

Lead sponsor

Pontificia Universidad Catolica de Chile

Other

Registry information

Important dates

Study start: 2012
Primary completion: 2012
Study completion: 2012
First posted: May 11, 2012
Registry last updated: May 11, 2012

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.

Completed