Post-operative use of dexmedetomidine in a pediatric cardiovascular intensive care unit

• Main Author: Halbrooks, Emma
• Language: en_US
• Published: Boston University 2015
• Online Access: https://hdl.handle.net/2144/12410

Thesis (M.A.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at [e-mail]. Thank you. === Introduction: Dexmedetomidine (DEX) was first approved by the Food and Drug Administration in 1999 for use as a sedative in adults who are initially intubated and require mechanical ventilation in an intensive care unit. DEX is not currently approved for use in children but its use to sedate children during radiologic procedures began to appear in the literature in 2005. The use of DEX in the pediatric population has expanded significantly since but appropriate dosage and clinical safety still needs further study. Children who have undergone heart surgery are a population that has benefited from DEX. A study of the pharmacokinetic properties of DEX in children indicated that children may benefit from higher dosages than the current dosage of 0.2-0. 7 mcg/kg/hr that is currently approved for adults (Suet al., 2011). Populations such as infants, neonates, and children with trisomy 21, in particular, have not been well described. At Children's Hospitals and Clinics of Minnesota, DEX is a frequently used sedative, often at higher dosages than 0.7 mcg/kg/hr and often in infants. Our retrospective study addresses DEX's effect on pediatric patients that are post-operative from cardiac surgery. Methods: Cardiac surgical cases that took place from April 2010 through April 2011 were reviewed. There were 107 patients who had heart surgery and received DEX post-operatively that were included in our study. Data regarding a patient's dosage, length of infusion, vital signs (heart rate, blood pressure, and respiratory rate) were collected every day that the patient received DEX. Evidence of withdrawal, adverse events, or any other adverse responses associated with the DEX infusion was also retrieved. Data regarding the patient vital signs were analyzed by age group: infant (less than one year), one to three years, and greater than three years, to compare against age-appropriate standards. All statistical analysis was conducted with SPSS 15.0 (Chicago, IL). Results: The average age of patients included was 6.2 months, with a range of 0.1 to 209.4 months. Seventy patients (approximately 65%) were infants. Nine patients (about 8%) were neonates (less than one month of age). The average weight was 6.5 kg. Patients were on DEX for a median of 1.6 days, to a maximum of 23.9 days. Their overall average dose was 0.83 mcg/kg/hr. Children age one to three years required the highest average dose of approximately 1 mcg/kg/hr. There was a statistically significant decrease in heart rate from baseline during the first 12 hours of infusion. The decrease in heart rate was most pronounced in infants and neonates. Systolic blood pressure decreased during the first 12 hours but was not statistically significant. The respiratory rate of extubated patients remained stable. A slight decrease could be seen in children greater than 3 years old but was not clinically significant. Children with trisomy 21 required the same dose of DEX as children without trisomy 21. There was no significant difference between the vital signs of children with trisomy 21 and children without. Incidence of withdrawal amongst patients was 5.7%. Agitation following the DEX infusion was higher in 17% of patients. An adverse event caused 6.5% of patients to be discontinued from DEX. Conclusions: Despite the statistically significant decreases in heart rate, the average values of patients' vital signs remained within the age-appropriate clinical standards. Patients were hemodynamically stable. Incidence of withdrawal and adverse events were low. Agitation after discontinuation was higher, particularly in infants. DEX is a safe sedative in this pediatric subpopulation.