Intranasal Dexmedetomidine for Sedation for Pediatric Computed Tomography Imaging Eduardo Mekitarian Filho, PhD1, Fay Robinson, MPH2, Werther Brunow de Carvalho, MD, PhD3, Alfredo Elias Gilio, MD4, and Keira P. Mason, MD5 This prospective observational pilot study evaluated the aerosolized intranasal route for dexmedetomidine as a safe, effective, and efficient option for infant and pediatric sedation for computed tomography imaging. The mean time to sedation was 13.4 minutes, with excellent image quality, no failed sedations, or significant adverse events. (J Pediatr 2015;-:---). Trial registration Registered with ClinicalTrials.gov: NCT01900405.
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omputed tomography (CT) imaging, albeit brief, frequently necessitates sedation for young infants and children. Currently, oral chloral hydrate and intravenous (IV) propofol and pentobarbital are the most commonly used sedation medications for CT imaging.1-5 Dexmedetomidine (DEX) (Precedex; Hospira, Lake Forest, Illinois) was approved in 2008 by the Food and Drug Administration as an IV sedative for procedures outside of the intensive care unit.6 The present prospective observational study evaluated the efficacy, image quality, and outcomes of aerosolized intranasal (AIN) DEX as the sole sedative for CT sedation.
Methods After Institutional Review Board approval and parental consent, children who presented to the Emergency Department in need of a CT imaging study and who met enrollment criteria (aged 1 month to 5 years; no need for or presence of an IV catheter; lies supine without clinical evidence of vomiting, reflux, or aspiration; ASA [American Society of Anesthesiologists] 1 or ASA 2) and without contraindications for DEX therapy7 (Table I) were recruited in a convenience sample by the principal investigator. Nil per os (NPO) criteria followed established guidelines for emergent sedation.8,9 An initial dose of 2.5 mg/kg of aerosolized undiluted (100 mg/mL) DEX was administered with a nasal mucosal atomizer device (Wolfe Tory Medical, Salt Lake City, Utah) by an emergency medicine nurse, under the direct supervision of a pediatrician. For optimal delivery, the child was positioned either supine or sitting with the head tilted back.
AIN ASA CT DEX IV NPO RSS
Aerosolized intranasal American Society of Anesthesiologists Computed tomography Dexmedetomidine Intravenous Nil per os Ramsay Sedation Scale
Baseline physiological measurements were documented and then obtained every 5 minutes after DEX administration, until a minimum modified Aldrete score of 9 was met for discharge. At 15 minutes after AIN DEX delivery, the depth of sedation was assessed using the Ramsay Sedation Scale (RSS).10 A minimum RSS score of 3 was required to ensure motionless conditions, and a second dose of 1 mg/kg AIN was administered if the RSS 3 was not achieved. Patient demographic data and outcome variables were documented. The World Society of Intravenous Anesthesia sedation outcome tool11 was applied to ensure standardization of the definitions of events, interventions, and outcome severity (Table II; available at www.jpeds. com). Two radiologists, blinded to the sedation technique, used a previously published scoring system12 to rate image quality (Table III; available at www.jpeds. com). Statistical Analyses Descriptive statistics were generated, including means and SDs for continuous variables and frequencies for categorical variables. All results were generated using SAS version 9.3 (SAS Institute, Cary, North Carolina). Demographic information included patient age, sex, weight, ASA physical status classification, and CT examination type. Efficacy measures included the number of DEX boluses administered (first and second dose), time (in minutes) to achieve sedation, time (in minutes from first dose) to meet discharge criteria, and NPO status (in minutes) before sedation. Outcome measures included heart rate, oxygen saturation, noninvasive blood pressure, and adverse events.
From the 1Pediatric Emergency Department, University Hospital, University of Sao Paulo and Hospital Israelita Albert Einstein, Sao Paulo, Brazil; 2DM-Stat, Inc, Malden, MA; 3Department of Pediatrics, Faculty of Medicine, 4Pediatric Emergency Department, University Hospital, University of Sao Paulo, Sao Paulo, Brazil; and 5 Department of Anesthesia, Harvard Medical School, Children’s Hospital Boston, Boston, MA The authors declare no conflicts of interest. 0022-3476/$ - see front matter. Copyright ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jpeds.2015.01.036
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Table I. Contraindications to Dex7 Active, uncontrolled gastroesophageal reflux—an aspiration risk Active, uncontrolled vomiting—an aspiration risk Current (or within past 3 months) history of apnea requiring an apnea monitor Active, current respiratory issues that are different from the baseline status (pneumonia, exacerbation of asthma, bronchitis, respiratory syncytial virus) Unstable cardiac status (life threatening arrhythmias, abnormal cardiac anatomy, significant cardiac dysfunction) Craniofacial anomaly which could make it difficult to effectively establish a mask airway for positive pressure ventilation if needed Current use of digoxin Moyamoya disease New onset stroke
(4.8%). In 100% of scans, image quality was graded as “excellent” and without motion or image artifacts. Hemodynamic variability was classified as a minor risk. Nine patients (15%) experienced a >20% decrease in heart rate, and 1 patient (1.7%) had a >20% drop in mean arterial blood pressure. Two patients (3.3%) experienced a 20% increase in mean arterial blood pressure, and 1 patient (1.7%) had a 20% increase in heart rate. No patient required pharmacologic intervention for the hemodynamic responses. There were no events categorized as sentinel risk.
Discussion Results Between June and December 2013, 60 patients (56.7% males; 80% ASA 1 and 20% ASA 2) underwent a total of 63 CT studies (82.5% head scans). Mean age was 17.1 9.5 months (median, 15.0 months; range, 3.0-43.0 months) and mean weight was 10.7 2.8 kg (median, 10.0 kg, range, 5.0-19.5 kg) (Table IV). Breast milk, infant formula, and full meals were most frequently reported as the last meal (20%, 23.3%, and 43.3%, respectively). The average NPO time was 206.3 123.6 minutes (median, 185.5 minutes; range, 35.0660.0 minutes) (Table IV). All patients received an initial AIN DEX dose of 2.5 mg/kg, and 3 (5%) required a second dose of 1 mg/kg. The time to achieve sedation averaged 13.4 6.4 minutes (median, 12.0 minutes; range, 5.0-40.0 minutes), and the time to meet discharge criteria (minimum modified Aldrete score 9) was 88.7 23.4 minutes (median, 86 minutes; range, 4.0-162.0 minutes). For those who required a second dose, the time to achieve sedation (measured from the time of the initial dose) was 35 5.0 minutes (median, 35.0 minutes; range, 30.0-40.0 minutes). All patients were successfully sedated. Prolonged recovery time (defined by more than 2 hours from the initial dose), hypoxia (pulse oximetry
C
omputed tomography (CT) imaging, albeit brief, frequently necessitates sedation for young infants and children. Currently, oral chloral hydrate and intravenous (IV) propofol and pentobarbital are the most commonly used sedation medications for CT imaging.1-5 Dexmedetomidine (DEX) (Precedex; Hospira, Lake Forest, Illinois) was approved in 2008 by the Food and Drug Administration as an IV sedative for procedures outside of the intensive care unit.6 The present prospective observational study evaluated the efficacy, image quality, and outcomes of aerosolized intranasal (AIN) DEX as the sole sedative for CT sedation.
Methods After Institutional Review Board approval and parental consent, children who presented to the Emergency Department in need of a CT imaging study and who met enrollment criteria (aged 1 month to 5 years; no need for or presence of an IV catheter; lies supine without clinical evidence of vomiting, reflux, or aspiration; ASA [American Society of Anesthesiologists] 1 or ASA 2) and without contraindications for DEX therapy7 (Table I) were recruited in a convenience sample by the principal investigator. Nil per os (NPO) criteria followed established guidelines for emergent sedation.8,9 An initial dose of 2.5 mg/kg of aerosolized undiluted (100 mg/mL) DEX was administered with a nasal mucosal atomizer device (Wolfe Tory Medical, Salt Lake City, Utah) by an emergency medicine nurse, under the direct supervision of a pediatrician. For optimal delivery, the child was positioned either supine or sitting with the head tilted back.
AIN ASA CT DEX IV NPO RSS
Aerosolized intranasal American Society of Anesthesiologists Computed tomography Dexmedetomidine Intravenous Nil per os Ramsay Sedation Scale
Baseline physiological measurements were documented and then obtained every 5 minutes after DEX administration, until a minimum modified Aldrete score of 9 was met for discharge. At 15 minutes after AIN DEX delivery, the depth of sedation was assessed using the Ramsay Sedation Scale (RSS).10 A minimum RSS score of 3 was required to ensure motionless conditions, and a second dose of 1 mg/kg AIN was administered if the RSS 3 was not achieved. Patient demographic data and outcome variables were documented. The World Society of Intravenous Anesthesia sedation outcome tool11 was applied to ensure standardization of the definitions of events, interventions, and outcome severity (Table II; available at www.jpeds. com). Two radiologists, blinded to the sedation technique, used a previously published scoring system12 to rate image quality (Table III; available at www.jpeds. com). Statistical Analyses Descriptive statistics were generated, including means and SDs for continuous variables and frequencies for categorical variables. All results were generated using SAS version 9.3 (SAS Institute, Cary, North Carolina). Demographic information included patient age, sex, weight, ASA physical status classification, and CT examination type. Efficacy measures included the number of DEX boluses administered (first and second dose), time (in minutes) to achieve sedation, time (in minutes from first dose) to meet discharge criteria, and NPO status (in minutes) before sedation. Outcome measures included heart rate, oxygen saturation, noninvasive blood pressure, and adverse events.
From the 1Pediatric Emergency Department, University Hospital, University of Sao Paulo and Hospital Israelita Albert Einstein, Sao Paulo, Brazil; 2DM-Stat, Inc, Malden, MA; 3Department of Pediatrics, Faculty of Medicine, 4Pediatric Emergency Department, University Hospital, University of Sao Paulo, Sao Paulo, Brazil; and 5 Department of Anesthesia, Harvard Medical School, Children’s Hospital Boston, Boston, MA The authors declare no conflicts of interest. 0022-3476/$ - see front matter. Copyright ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jpeds.2015.01.036
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THE JOURNAL OF PEDIATRICS
Vol. -, No. -
www.jpeds.com
Table I. Contraindications to Dex7 Active, uncontrolled gastroesophageal reflux—an aspiration risk Active, uncontrolled vomiting—an aspiration risk Current (or within past 3 months) history of apnea requiring an apnea monitor Active, current respiratory issues that are different from the baseline status (pneumonia, exacerbation of asthma, bronchitis, respiratory syncytial virus) Unstable cardiac status (life threatening arrhythmias, abnormal cardiac anatomy, significant cardiac dysfunction) Craniofacial anomaly which could make it difficult to effectively establish a mask airway for positive pressure ventilation if needed Current use of digoxin Moyamoya disease New onset stroke
(4.8%). In 100% of scans, image quality was graded as “excellent” and without motion or image artifacts. Hemodynamic variability was classified as a minor risk. Nine patients (15%) experienced a >20% decrease in heart rate, and 1 patient (1.7%) had a >20% drop in mean arterial blood pressure. Two patients (3.3%) experienced a 20% increase in mean arterial blood pressure, and 1 patient (1.7%) had a 20% increase in heart rate. No patient required pharmacologic intervention for the hemodynamic responses. There were no events categorized as sentinel risk.
Discussion Results Between June and December 2013, 60 patients (56.7% males; 80% ASA 1 and 20% ASA 2) underwent a total of 63 CT studies (82.5% head scans). Mean age was 17.1 9.5 months (median, 15.0 months; range, 3.0-43.0 months) and mean weight was 10.7 2.8 kg (median, 10.0 kg, range, 5.0-19.5 kg) (Table IV). Breast milk, infant formula, and full meals were most frequently reported as the last meal (20%, 23.3%, and 43.3%, respectively). The average NPO time was 206.3 123.6 minutes (median, 185.5 minutes; range, 35.0660.0 minutes) (Table IV). All patients received an initial AIN DEX dose of 2.5 mg/kg, and 3 (5%) required a second dose of 1 mg/kg. The time to achieve sedation averaged 13.4 6.4 minutes (median, 12.0 minutes; range, 5.0-40.0 minutes), and the time to meet discharge criteria (minimum modified Aldrete score 9) was 88.7 23.4 minutes (median, 86 minutes; range, 4.0-162.0 minutes). For those who required a second dose, the time to achieve sedation (measured from the time of the initial dose) was 35 5.0 minutes (median, 35.0 minutes; range, 30.0-40.0 minutes). All patients were successfully sedated. Prolonged recovery time (defined by more than 2 hours from the initial dose), hypoxia (pulse oximetry
