Pharmacokinetics of Dexmedetomidine in Children During Cardiopulmonary Bypass (CPB)

N/ACompletedNCT02059343

Duke University18 enrolled

Overview

Dexmedetomidine is increasingly used for sedation in children placed on cardiopulmonary bypass for heart surgery. It is also often used after surgery and may be particularly helpful for children with heart disease. In order for this medication to be helpful and to minimize risks associated with taking the medication, it is important to provide correct dosing for this medication. Based on evidence from studies of other medications used during heart surgery, it is likely that dosing of dexmedetomidine while on cardiopulmonary bypass is different from dosing in other settings. The purpose of this study is to evaluate how the heart-lung bypass machine affects dexmedetomidine levels in the body.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Pharmacokinetics Cardiopulmonary Bypass Children

Eligibility

Sex: ALLMax age: 2 Years

Medical Language ↔ Plain English

Inclusion Criteria: * \< 2 years of age * Sufficient venous access to permit administration of study medication. * Supported with cardiopulmonary bypass (CPB) * Receiving dexmedetomidine per standard of care. * Availability and willingness of the parent/legal guardian to provide written informed consent. Exclusion Criteria: * \<38 weeks post menstrual age * Any concomitant condition, which in the opinion of the investigator would preclude a subject's participation in the study. * Previous participation in this study * CPB circuit primed with clear fluid

Outcomes

Primary Outcomes

Plasma pharmacokinetics (clearance, volume of distribution, area under the curve, oxygenator extraction efficiency) of dexmedetomidine in children supported with cardiopulmonary bypass

The plasma pharmacokinetics of dexmedetomidine will include * Clearance (CL) * Volume of distribution (V) * Area under the curve (AUC) * Oxygenator extraction efficiency

Time frame: Data will be collected at the following approximate time points: 0h, 0.5h, 0.75h, and 2h after infusion initiation; 0.25h, 0.75h, and 2h after bypass initiation; 0.5h prior to bypass termination, 0.25h, 1h, 3h, 7h, and 10h after bypass termination

Secondary Outcomes

COMFORT behavioral score as a measure of dexmedetomidine pharmacodynamics

Time frame: assessed at time 0, upon presentation to the intensive care unit after surgery, and 12-24 hours from study drug initiation.

Accessory sedative and analgesic use as a measure of dexmedetomidine pharmacodynamics

We will monitor sedatives and analgesics used in addition to dexmedetomidine. Quantification of use of other drugs will allow an indication of the sedative effects of dexmedetomidine.

Time frame: up to 48 hours after study drug initiation