848

Abstract

Introduction: There are concerns that fluid abstinence prior to sedation may put patients at risk for hypotension during sedation. This risk may be increased in children. Methods: This study is a retrospective chart review of 263 children who received intravenous (IV) Propofol by bolus then continuous infusion to complete magnetic resonance imaging from June 2011 through May 2013. All patients were instructed to take nothing by mouth as directed by the American Society of Anesthesiologists preoperative fasting guideline. Actual time of abstinence was documented prior to initiation of sedation. Study data included patient characteristics (gender, age, and weight), propofol bolus dose and infusion rate and hemodynamic parameters were measured at baseline and 5 minute intervals for the sedation duration which is routine per policy. IV fluid received was also recorded. Total and percent maximum decrease in systolic blood pressure (SBP) and mean arterial pressure (MAP) relative to baseline were calculated. Max SBP and MAP decreases were also dichotomized at 25 SBP units (SBPdrop25) and 20% MAP (pctMAPdrop20). Associations of hemodynamic changes with fluid abstinence and other patient characteristics were explored with linear correlation and logistic regression analyses. Results: Mean fluid abstinence time was 538.4 +/- 294.0 minutes, propofol bolus dose 2.4 +/- 0.9 mg/kg, propofol infusion rate dose 160.1 +/- 29.3 g/kg/min, and duration 51.6 +/- 24.8 minutes. Duration of procedure, baseline SBP and MAP were significantly correlated with blood pressure decreases but not with fluid abstinences time. Fluid abstinence time was not significantly correlated with maximum SBP decrease (r = 0.02, p = .727) or maximum percent MAP decrease (r = 0.08, p = .20). Logistic regression showed no significant relationships between fluid abstinence time and SBPdrop25 (O.R. 1.0, 95% C.I. 1.00 – 1.01) or pctMAPdrop20 (O.R. 1.0, 95% C.I. 1.00 – 1.01). Conclusions: In our study duration of fluid abstinence prior to sedation with Propofol is not independently associated with hemodynamic changes in children.