Ketamine Pharmacokinetics in Children Having Heart Surgery

Brief Summary

What are the pharmacokinetics of ketamine in infants and children requiring ketamine for induction of anesthesia for cardiac surgery that requires CPB? Specific Aim 1: To determine the pharmacokinetic parameters of a single intravenous bolus dose of ketamine in infants and children undergoing cardiac surgery with and without CPB (cardio-pulmonary bypass). Specific Aim 2: To describe the disposition of ketamine's primary active metabolite, norketamine,following a single intravenous bolus dose of ketamine in infants and children undergoing cardiac surgery with and without CPB. Specific Aim 3: To determine the relationship between ketamine and norketamine pharmacokinetic parameters and age as well as CPB time.

Intervention / Treatment

  • Ketamine (DRUG)
    subject will then receive an intravenous bolus dose of ketamine 2 mg/kg as a rapid intravenous bolus, over less than two minutes just prior to CPB. In the non-CPB patients, ketamine will be administered just prior to the skin incision. All doses will be rounded to the nearest tenth of a milligram. Timed blood samples will be collected at standardized times after the completion of the ketamine infusion and samples will be obtained from an indwelling arterial line. Each blood sample for pharmacokinetic analysis will be 1 mL.

Condition or Disease

  • C.Surgical Procedure; Cardiac

Phase

  • Not Applicable
  • Study Design

    Study type: INTERVENTIONAL
    Status: Completed
    Study results: No Results Available
    Age: 1 Day to 6 Years
    Enrollment: 18 (ACTUAL)
    Funded by: Other
    Allocation: N/A
    Primary Purpose: Supportive Care

    Masking

    Clinical Trial Dates

    Start date: Jun 01, 2006
    Primary Completion: Jan 01, 2009 ACTUAL
    Completion Date: Dec 01, 2009 ACTUAL
    Study First Posted: Jan 21, 2008 ESTIMATED
    Results First Posted: Aug 31, 2020
    Last Updated: Feb 26, 2013

    Sponsors / Collaborators

    Lead sponsor is responsible party
    Responsible Party: N/A

    The role of ketamine in pediatric anesthesia is well established. It is one of the most commonly used agents for conscious sedation in pediatrics. Its widespread use stems for its abrupt onset of action and brief duration of sedation. There is limited ketamine pharmacokinetic data in children and none to our knowledge in infants and young children who will be given an intravenous bolus dose before a surgical procedure that includes cardiopulmonary bypass.

    Ketamine is marketed as a racemic mixture (50:50 mixture of S- and R-ketamine enantiomers).

    Ketamine undergoes N-demethylation (CYP3B6, 2C9, and 3A4) to its primary active metabolite,norketamine, with minor inactive metabolites, dehydroxynorketamine, generated secondary to direct oxidation. Ketamine exhibits a high intrinsic clearance with hepatic clearance dependent on hepatic blood flow under normal circumstances. One inherent disadvantage associated with the use of cardiopulmonary bypass (CPB) is the potential for organ dysfunction post-operatively.

    We propose an open-label controlled study describing the disposition of ketamine in 28 infants and children who will be undergoing cardiac surgery with (n=16) and without (n=12) CPB. We anticipate that cardiopulmonary bypass alters the pharmacokinetics of ketamine.

    Participant Groups

    • The pharmacokinetic action of Ketamine used in Children having heart surgery.

    Eligibility Criteria

    Sex: All
    Maximum Age: 6
    Age Groups: Child
    Healthy Volunteers: Yes

    Inclusion Criteria:

    * ≤ 6 years of age
    * cardiac surgical procedure
    * Indwelling arterial line or central venous line for blood sampling

    Exclusion Criteria:

    * patients with known hepatic dysfunction(\>3 times normal AST \& ALT)
    * clinically significant alteration (as determined by the investigator) hemoglobin or hematocrit
    * patients receiving medications known to be potent inhibitors or inducers of CYP3A4 and CYP2C19
    * patients with significant malnutrition (\< 1%tile for age-adjusted weight)
    * patients enrolled in other studies that require frequent blood sampling during and after cardiac surgery
    * any contraindication for ketamine administration
    * ketamine administration within the previous 24 hours
    * Patients with known history of pulmonary hypertension

    Primary Outcomes
    • To measure how long ketamine remains in blood after a single dose of ketamine is given (venous) to children undergoing cardiac surgery on cardiopulmonary bypass (CPB)compared to levels of children undergoing cardiac surgery without CPB. Length of time ketamine remains in the blood

    More Details

    NCT Number: NCT00598195
    Other IDs: 57839
    Study URL: https://clinicaltrials.gov/study/NCT00598195
    Last updated: Sep 29, 2023