Hemodynamic response to fluid management in children undergoing dexmedetomidine sedation for MRI.
OBJECTIVE
Dexmedetomidine is administered for pediatric sedation for MRI studies. It has the advantage of preserving respiratory function and producing a sedation state identical to that of natural sleep. It can, however, cause a dose-dependent decrease in systemic blood pressure in children. The purpose of this study was to investigate whether i.v. fluid loading with normal saline solution before the initiation of dexmedetomidine administration would affect the frequency of hypotension.


METHODS
Quality assurance data on consecutively registered children who were sedated with dexmedetomidine for MRI were reviewed. All children received a bolus of 3 μg/kg dexmedetomidine followed by a continuous infusion of 2 mg/ kg/h. A normal saline fluid bolus consisting of 0, 10, or 20 mL/kg was administered to each child within 1 hour before initiation of dexmedetomidine administration. Hypotension was defined as a greater than 20% decrease in mean arterial blood pressure from baseline.


RESULTS
Sedation was administered to 1692 children. Data on fluid administration were missing in three cases. In the other cases, 252 (14.9%) children received 0 mL/kg of normal saline solution, 598 (35.3%) received 10 mL/kg, and 839 (49.6%) received 20 mL/kg. In a multiple logistic regression model controlled for confounding variables, the odds of development of hypotension with 10 mL/kg of fluid decreased 53% (odds ratio, 0.47; 95% CI, 0.28-0.79; p = 0.004) compared with 0 mL/kg.


CONCLUSIONS
Administration of 10 mL/kg of normal saline solution before the initiation of dexmedetomidine administration for pediatric MRI sedation is effective in decreasing the incidence of observed hypotension.
1 Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital, 300 Longwood Ave, Boston, MA 02115.
Keira P
KP
Mason
Dana P
DP
Turner
Timothy T
TT
Houle
Paulette J
PJ
Fontaine
Jerrold
J
Lerman
D000293:Adolescent; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D020927:Dexmedetomidine / Q000008:administration & dosage / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects; D007022:Hypotension / Q000139:chemically induced* / Q000503:physiopathology / Q000517:prevention & control*; D007089:Image Enhancement / Q000379:methods; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012189:Retrospective Studies; D012462:Saline Solution, Hypertonic / Q000008:administration & dosage*; D016896:Treatment Outcome; D055815:Young Adult
D006993:Hypnotics and Sedatives; D012462:Saline Solution, Hypertonic; D020927:Dexmedetomidine