Use of dexmedetomidine in the pediatric intensive care unit

Dexmedetomidine Withdrawal Syndrome in Children in the PICU: Systematic Review and Meta-Analysis

OBJECTIVES

To systematically review literature describing the clinical presentation, risk factors, and treatment for dexmedetomidine withdrawal in the PICU (PROSPERO: CRD42022307178).

DATA SOURCES

MEDLINE/PubMed, Cochrane, Web of Science, and Scopus databases were searched.

STUDY SELECTION

Eligible studies were published from January 2000 to January 2022 and reported clinical data for patients younger than 21 years old following discontinuation of dexmedetomidine after greater than or equal to 24 hours of infusion.

DATA EXTRACTION

Abstracts identified during an initial search were screened and data were manually abstracted after full-text review of eligible articles. The Newcastle-Ottawa Scale was used to assess study quality. Summary statistics were provided and Spearman rank correlation coefficient was used to identify relationships between covariates and withdrawal signs. A weighted prevalence for each withdrawal sign was generated using a random-effects model.

DATA SYNTHESIS

Twenty-three studies (22 of which were retrospective cohort studies) containing 28 distinct cohorts were included. Median cumulative dexmedetomidine exposure by dose was 105.95 μg/kg (range, 30-232.7 μg/kg), median dexmedetomidine infusion duration was 131.75 hours (range, 20.5-525.6 hr). Weighted estimates for proportion (95% CI) of subjects experiencing withdrawal signs across all cohorts were: hypertension 0.34 (range, 0.0-0.92), tachycardia 0.26 (range, 0.0-0.87), and agitation 0.26 (range, 0.09-0.77). Meta-analysis revealed no correlation between dexmedetomidine exposure variables and withdrawal signs. A moderate negative monotonic relationship existed between the proportion of patients who had undergone cardiac surgery and the proportion experiencing hypertension (correlation coefficient, -0.47; p = 0.048) and tachycardia (correlation coefficient, -0.57; p = 0.008), indicating that in cohorts with a higher proportion of patients who were postcardiac surgery, there were fewer occurrences of hypertension and or tachycardia.

CONCLUSIONS

On review of the 2000-2022 literature, dexmedetomidine withdrawal may be characterized by tachycardia, hypertension, or agitation, particularly with higher cumulative doses or prolonged durations. Since most studies included in the review were retrospective, prospective studies are needed to further clarify risk factors, establish diagnostic criteria, and identify optimal management strategies.

Impact of Dexmedetomidine Infusion on Opioid and Benzodiazepine Doses in Ventilated Pediatric Patients in the Cardiac Intensive Care Unit

INTRODUCTION

Dexmedetomidine (DEX) is frequently used as an adjunct agent for prolonged sedation in the intensive care unit (ICU), though its effect on concomitant opioids or benzodiazepines infusions is unclear. We explored the impact of DEX on concomitant analgosedation in a cohort of ventilated pediatric patients in a cardiac ICU, with stratification of patients according to duration of ventilation (< 5 versus ≥ 5 days) following DEX initiation.

METHODS

We conducted a retrospective analysis on ventilated patients receiving a DEX infusion ≥ 24 h and at least one other sedative/analgesic infusion (January 2011-June 2021). We evaluated trends of daily doses of opioids and benzodiazepines from 24 h before to 72 h following DEX initiation, stratifying patients based on ventilation duration after DEX initiation (< 5 versus ≥ 5 days).

RESULTS

After excluding 1146 patients receiving DEX only, 1073 patients were included [median age 234 days (interquartile range 90, 879)]. DEX was associated with an opioid infusion in 99% of patients and a benzodiazepine infusion in 62%. Among patients ventilated for < 5 days (N = 761), opioids increased in the first 24 h following DEX initiation [+ 1.12 mg/kg/day (95% CI 0.96, 1.23), P < 0.001], then decreased [- 0.90 mg/kg/day (95% CI - 0.89, - 0.71), P < 0.001]; benzodiazepines slowly decreased [- 0.20 mg/kg/day (95% CI - 0.21, - 0.19), P < 0.001]. Among patients ventilated for ≥ 5 days (N = 312), opioid administration doubled [+ 2.09 mg/kg/day (95% CI 1.82, 2.36), P < 0.001] in the first 24 h, then diminished minimally [- 0.18 mg/kg/day (95% CI - 0.32, - 0.04), P = 0.015] without returning to baseline; benzodiazepine administration decreased minimally [- 0.03 mg/kg/day (95% CI - 0.05, - 0.01), P = 0.010]. Similar trends were confirmed when adjusting for age, gender, surgical complexity, recent major invasive procedures, duration of mechanical ventilation before DEX initiation, extubation within 72 h following DEX initiation, mean hourly DEX dose, and use of neuromuscular blocking infusion.

CONCLUSION

While in patients ventilated < 5 days opioids initially increased and then quickly decreased in the 72 h following DEX initiation, among patients ventilated ≥ 5 days opioids doubled, then decreased only minimally; benzodiazepines decreased minimally in both groups, although more slowly in the long-ventilation cohort. These findings may inform decision-making on timing of DEX initiation in ventilated patients already being treated with opioid or benzodiazepine infusions.

Dexmedetomidine for Prolonged Sedation in the PICU: A Systematic Review and Meta-Analysis

OBJECTIVES

We aimed to systematically describe the use of dexmedetomidine as a treatment regimen for prolonged sedation in children and perform a meta-analysis of its safety profile.

DATA SOURCES

PubMed, EMBASE, Cochrane Library, Scopus, Web of Science, ClinicalTrials.gov, and CINAHL were searched from inception to November 30, 2018.

STUDY SELECTION

We included studies involving hospitalized critically ill patients less than or equal to 18 years old receiving dexmedetomidine for prolonged infusion (≥ 24 hr).

DATA EXTRACTION

Data extraction included study characteristics, patient demographics, modality of dexmedetomidine use, associated analgesia and sedation details, comfort and withdrawal evaluation scales, withdrawal symptoms, and side effects.

DATA SYNTHESIS

Literature search identified 32 studies, including a total of 3,267 patients. Most of the studies were monocentric (91%) and retrospective (88%); one was a randomized trial. Minimum and maximum infusion dosages varied from 0.1-0.5 µg/kg/hr to 0.3-2.5 µg/kg/hr, respectively. The mean/median duration range was 25-540 hours. The use of a loading bolus was reported in eight studies (25%) (range, 0.5-1 µg/kg), the mode of weaning in 11 (34%), and the weaning time in six of 11 (55%; range, 9-96 hr). The pooled prevalence of bradycardia was 2.6% (n = 10 studies; 14/387 patients; 95% CI, 0.3-7.3; I = 75%), the pooled prevalence incidence of bradycardia was 2.6% (n = 10 studies; 14/387 patients; 95% CI, 0.3-7.3; I = 75%), the pooled incidence of hypotension was 6.1% (n = 8 studies; 19/304 patients; 95% CI, 0.8-15.9; I = 84%). Three studies (9%) reported side effects' onset time which in all cases was within 12 hours of the infusion starting.

CONCLUSIONS

High-quality data on dexmedetomidine use for prolonged sedation and a consensus on correct dosing and weaning protocols in children are currently missing. Infusion of dexmedetomidine can be considered relatively safe in pediatrics even when longer than 24 hours.

Efficacy and Safety of Dexmedetomidine for Prolonged Sedation in the PICU: A Prospective Multicenter Study (PROSDEX)

OBJECTIVES

We sought to evaluate dexmedetomidine efficacy in assuring comfort and sparing conventional drugs when used for prolonged sedation (≥24 hr) in critically ill patients, by using validated clinical scores while systematically collecting drug dosages. We also evaluated the safety profile of dexmedetomidine and the risk factors associated with adverse events.

DESIGN

Observational prospective study.

SETTING

Nine tertiary-care PICUs.

PATIENTS

Patients less than 18 years who received dexmedetomidine for greater than or equal to 24 hours between January 2016 and December 2017.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One-hundred sixty-three patients (median age, 13 mo; interquartile range, 4-71 mo) were enrolled. The main indication for dexmedetomidine use was as an adjuvant for drug-sparing (42%). Twenty-three patients (14%) received dexmedetomidine as monotherapy. Seven percent of patients received a loading dose. The median infusion duration was 108 hours (interquartile range, 60-168 hr), with dosages between 0.4 (interquartile range, 0.3-0.5) and 0.8 µg/kg/hr (interquartile range, 0.6-1.2 µg/kg/hr). At 24 hours of dexmedetomidine infusion, values of COMFORT-B Scale (n = 114), Withdrawal Assessment Tool-1 (n = 43) and Cornell Assessment of Pediatric Delirum (n = 6) were significantly decreased compared with values registered immediately pre dexmedetomidine (p < 0.001, p < 0.001, p = 0.027). Dosages/kg/hr of benzodiazepines, opioids, propofol, and ketamine were also significantly decreased (p < 0.001, p < 0.001, p = 0.001, p = 0.027). The infusion was weaned off in 85% of patients, over a median time of 36 hours (interquartile range, 12-48 hr), and abruptly discontinued in 15% of them. Thirty-seven percent of patients showed hemodynamic changes, and 9% displayed hemodynamic adverse events that required intervention (dose reduction in 79% of cases). A multivariate logistic regression model showed that a loading dose (odds ratio, 4.8; CI, 1.2-18.7) and dosages greater than 1.2 µg/kg/hr (odds ratio, 5.4; CI, 1.9-15.2) increased the odds of hemodynamic changes.

CONCLUSIONS

Dexmedetomidine used for prolonged sedation assures comfort, spares use of other sedation drugs, and helps to attenuate withdrawal syndrome and delirium symptoms. Adverse events are mainly hemodynamic and are reversible following dose reduction. A loading dose and higher infusion dosages are independent risk factors for hemodynamic adverse events.

The Impact of a Clonidine Transition Protocol on Dexmedetomidine Withdrawal in Critically Ill Pediatric Patients

OBJECTIVES

This study describes our experience with a clonidine transition protocol to prevent dexmedetomidine (DEX) withdrawal in critically ill pediatric patients.

METHODS

Retrospective review of electronic medical records of patients in the pediatric intensive care unit of a single tertiary children's hospital. All patients up to 19 years of age, who received concomitant DEX infusion and enteral clonidine between June 1, 2016, and May 31, 2018, were included.

RESULTS

Two of 24 encounters had DEX restarted for withdrawal (8.3%). Five of 14 encounters who were transitioned to clonidine 2 mcg/kg every 6 hours required an increased dose, and 1 of 10 encounters transitioned to clonidine 4 mcg/kg every 6 hours required an increased dose (36% vs 10%, p = 0.21). For encounters with clonidine dose increases, 5 of 6 had improvements in Withdrawal Assessment Tool-1 (WAT-1) scores. Of these 5 encounters, 4 had decreasing or stable opioid and sedative requirements and 1 was transitioned to methadone. No encounters required discontinuation of clonidine owing to adverse events. Two of 24 encounters met our safety endpoint. One received a fluid bolus during the clonidine transition with no change in clonidine dosing, while the other had clonidine dose decreased for asymptomatic bradycardia.

CONCLUSIONS

The 24 encounters in our retrospective study add to the limited literature available to describe dosing, initiation time, and duration of clonidine to prevent withdrawal from DEX in critically ill pediatric patients. Further research is needed to clarify the optimal dosing and duration of clonidine to prevent DEX withdrawal in pediatric patients.

[Progress in perioperative pain management of pediatric and adolescent spinal deformity corrective surgery]

OBJECTIVE

To review the advances in perioperative pain management of pediatric and adolescent spinal deformity corrective surgery.

METHODS

Regular analgesics, drug administrations, and analgesic regimens were reviewed and summarized by consulting domestic and overseas related literatures about perioperative pain management of pediatric and adolescent spinal deformity corrective surgery in recent years.

RESULTS

As for perioperative analgesis regimens of pediatric and adolescent spinal deformity corrective surgery, regular analgesics include non-steroidal anti-inflammatory drugs, opioids, antiepileptic drugs, adrenergic agonists, and local anesthetic, etc. Besides drug administration by mouth, intravenous injection, and intramuscular injection, the administration also includes patient controlled analgesia, epidural injection, and intrathecal injection. Multimodal analgesia is the most important regimen currently.

CONCLUSION

Heretofore, a number of perioperative pain managements of pediatric and adolescent spinal deformity corrective surgery have been applied clinically, but the ideal regimen has not been developed. To design a safe and effective analgesic regimen needs further investigations.

Survey of the Current Use of Dexmedetomidine and Management of Withdrawal Symptoms in Critically Ill Children

OBJECTIVES

Dexmedetomidine use for sedation in the pediatric intensive care units (PICUs) has increased since its initial US Food and Drug Administration (FDA) approval in adults. However, there is limited evidence to direct providers regarding current usage, dosing, and monitoring for withdrawal symptoms in pediatric patients. This study sought to determine the utilization of dexmedetomidine and management of dexmedetomidine withdrawal symptoms among PICU physicians.

METHODS

A questionnaire survey was distributed to all members of the American Academy of Pediatrics Section on Critical Care. It assessed the practice site demographics, indication, dosing, and duration of dexmedetomidine infusion, unit protocol, and strategies for management of dexmedetomidine withdrawal.

RESULTS

A total of 147 surveys (21.1%) were returned and analyzed. The reported uses for dexmedetomidine were as a primary sedative (59.9%), adjunctive agent for sedation (82.3%), and adjunctive agent to assist weaning sedation (62.6%) or from mechanical ventilation (70.1%). One hundred twenty-nine respondents (87.8%) had concerns over dexmedetomidine withdrawal, with 59 respondents becoming concerned after 120 hours of infusion (45.7%). Most respondents reported managing dexmedetomidine withdrawal symptoms via a regimented wean and initiation of clonidine (81%). Units with >1000 admissions per year were more likely to have a protocol related to dexmedetomidine use (p = 0.021). Units with >1000 admissions per year reported using clonidine for withdrawal at a higher rate, whereas units with ≤1000 admissions per year used a systematic wean of dexmedetomidine (p = 0.014).

CONCLUSIONS

Dexmedetomidine use in the PICU is varied among pediatric intensive care physicians. Intensivists have withdrawal concerns after dexmedetomidine discontinuation, and the primary management of this withdrawal phenomenon is the initiation of clonidine with a regimented dexmedetomidine wean.

Prolonged sedation in critically ill children: is dexmedetomidine a safe option for younger age? An off-label experience

BACKGROUND

Dexmedetomidine (DEX) is an alpha-2-adrenergic agonist, recently approved by Italian-Medicines-Agency for difficult sedation in pediatrics, but few data exist regarding prolonged infusions in critically-ill children, especially in younger ages. Aim of our study was to evaluate DEX use and safety for prolonged sedation in Pediatric Intensive Care Units (PICUs).

METHODS

Patients receiving DEX for ≥24 hours were retrospectively evaluated to analyze DEX indications, dosages, use of analgesics or sedatives, adverse events (AEs), withdrawal syndrome or delirium.

RESULTS

Forty-seven patients (median 0.7years) from nine PICUs were enrolled. Main indications were adjuvant for drugs sparing (59.6%) and for analgosedation weaning (36.2%). Median infusion duration was 82.0 hours (IQR 62.2-126.0), with dosages between 0.4 (IQR 0.2-0.5) and 0.8 mcg/kg/h (IQR 0.6-1.2). Fifty-nine-percent of patients received other sedatives, 83% other analgesics. Twenty-one-percent presented withdrawal syndrome, 4.2% delirium, none of them DEX-related. Forty-six-percent experienced a potentially-DEX-related AE. AEs were all hemodynamic, 14.9% requiring intervention but none DEX interruption. The median minimum and maximum dosages were significantly higher in patients with AEs (0.5 vs. 0.3,P=0.001; 1.0 vs. 0.7,P<0.001), without correlations with the infusion duration. AEs rate was higher in patients receiving benzodiazepines (P=0.020) or more than one analgesic (P=0.003) and in those presenting withdrawal syndrome (P<0.001).

CONCLUSIONS

DEX was confirmed as useful and relatively safe drug for prolonged sedation in critically-ill children, particularly in younger ages. Main AEs were cardiovascular, reversible, related with higher doses, with the concomitant use of benzodiazepines or multiple sedation drugs and with the presence of withdrawal syndrome.

Dexmedetomidine Use in Critically Ill Children With Acute Respiratory Failure

OBJECTIVE

Care of critically ill children includes sedation but current therapies are suboptimal. To describe dexmedetomidine use in children supported on mechanical ventilation for acute respiratory failure.

DESIGN

Secondary analysis of data from the Randomized Evaluation of Sedation Titration for Respiratory Failure clinical trial.

SETTING

Thirty-one PICUs.

PATIENTS

Data from 2,449 children; 2 weeks to 17 years old.

INTERVENTIONS

Sedation practices were unrestrained in the usual care arm. Patients were categorized as receiving dexmedetomidine as a primary sedative, secondary sedative, periextubation agent, or never prescribed. Dexmedetomidine exposure and sedation and clinical profiles are described.

MEASUREMENTS AND MAIN RESULTS

Of 1,224 usual care patients, 596 (49%) received dexmedetomidine. Dexmedetomidine as a primary sedative patients (n = 138; 11%) were less critically ill (Pediatric Risk of Mortality III-12 score median, 6 [interquartile range, 3-11]) and when compared with all other cohorts, experienced more episodic agitation. In the intervention group, time in sedation target improved from 28% to 50% within 1 day of initiating dexmedetomidine as a primary sedative. Dexmedetomidine as a secondary sedative usual care patients (n = 280; 23%) included more children with severe pediatric acute respiratory distress syndrome or organ failure. Dexmedetomidine as a secondary sedative patients experienced more inadequate pain (22% vs 11%) and sedation (31% vs 16%) events. Dexmedetomidine as a periextubation agent patients (n = 178; 15%) were those known to not tolerate an awake, intubated state and experienced a shorter ventilator weaning process (2.1 vs 2.3 d).

CONCLUSIONS

Our data support the use of dexmedetomidine as a primary agent in low criticality patients offering the benefit of rapid achievement of targeted sedation levels. Dexmedetomidine as a secondary agent does not appear to add benefit. The use of dexmedetomidine to facilitate extubation in children intolerant of an awake, intubated state may abbreviate ventilator weaning. These data support a broader armamentarium of pediatric critical care sedation.

Emergency Corrective Surgery of Congenital Diaphragmatic Hernia With Pulmonary Hypertension: Prolonged Use of Dexmedetomidine as a Pharmacologic Adjunct

INTRODUCTION

Underdevelopment of the lung parenchyma associated with abnormal growth of pulmonary vasculature in neonates with congenital diaphragmatic hernia results in pulmonary hypertension which mandates smooth elective mechanical ventilation in postoperative period, for proper alveolar recruitment and oxygenation, allowing lungs to mature enough for its functional anatomy and physiology. Dexmedetomidine is sympatholytic, reduces pulmonary vascular resistance and exerts sedative and analgesic property to achieve stable hemodynamics during elective ventilation. Neonatal experience with dexmedetomidine has been predominately in the form of short term or procedural use as a sedative.

CASE PRESENTATION

The preliminary clinical experience with pre-induction to 48 hours postoperative use of dexmedetomidine infusion as a pharmacologic adjunct in the emergency corrective surgery of three such neonates are presented.

CONCLUSIONS

Hemodynamics remained virtually stable during the whole procedure and post-operative pain relief and recovery profile were satisfactory. The prolonged infusion was well tolerated with a gradual trend towards improved oxygen saturation. Careful planning of the anesthetic management and the ability to titrate the adjunct utilized for smooth postoperative ventilation are the keys to ameliorate the complications encountered and favorable outcomes achieved in such patients.

Pain and Sedation Management in Mechanically Ventilated Children

Assessing and managing pain and agitation in critically ill children can be challenging. Multiple factors contribute to the challenges of management, including prior medication exposure, surgical and procedural interventions, pharmacokinetics, and age-related pharmacodynamics making the population heterogeneous. Therefore, individualizing treatment approaches embedded with frequent assessments is likely to improve the management of pain and agitation in critically ill children. Novel approaches to manage pain and agitation continue to evolve and will require ongoing evaluation prior to widespread adoption.

Characterization of dexmedetomidine dosing and safety in neonates and infants

OBJECTIVES

To describe and compare off-label use and cardiovascular (CV) adverse effects of dexmedetomidine in neonates and infants in the pediatric intensive care unit (PICU).

METHODS

Patients younger than 12 months with corrected gestational ages of at least 37 weeks who were receiving continuous infusion of dexmedetomidine at a tertiary pediatric referral center between October 2007 and August 2012 were assessed retrospectively. Patients were excluded if dexmedetomidine was used for procedural sedation, postoperative CV surgery, or if postanesthesia infusion weaning orders existed at the time of PICU admission.

RESULTS

The median minimum dexmedetomidine dose was similar between infants and neonates at 0.2 mcg/kg/hr (IQR, 0.17-0.3) versus 0.29 mcg/kg/hr (IQR, 0.2-0.31), p = 0.35. The median maximum dose was higher for infants than neonates (0.6 mcg/kg/hr [IQR, 0.4-0.8] vs. 0.4 mcg/kg/hr [IQR, 0.26-0.6], p < 0.01). Additional sedative use was more common in infants than neonates (75/99 [76%] vs. 15/28 [54%], p = 0.02). At least 1 episode of hypotension was noted in 34/127 (27%) patients and was similar between groups. An episode of bradycardia was identified more frequently in infants than neonates (55/99 [56%] vs. 2/28 [7%], p < 0.01). Significant reduction in heart rate and systolic blood pressure was noted when comparing baseline vital signs to lowest heart rate and systolic blood pressure during infusion (p < 0.01).

CONCLUSIONS

Dexmedetomidine dose ranges were similar to US Food and Drug Administration-labeled dosages for intensive care unit sedation in adults. More infants than neonates experienced a bradycardia episode, but infants were also more likely to receive higher dosages of dexmedetomidine and additional sedatives.

Dexmedetomidine in combination with midazolam after pediatric cardiac surgery

Objective

Although midazolam is one of the most commonly used sedatives for infants in the intensive care unit, it has well-known disadvantages including a dose-dependent potential to induce tolerance, withdrawal, and hemodynamic depression. The aim of this study was to evaluate the clinical effects of dexmedetomidine combined with midazolam in postoperative intensive care following pediatric cardiac surgery.

Methods

Forty consecutive infants who underwent cardiac surgery for isolated ventricular septal defects from January 2011 to July 2013 were enrolled in this retrospective study. They were divided into two groups according to postoperative sedation regimen: dexmedetomidine sedation with midazolam ( n = 20), or midazolam sedation without dexmedetomidine (control group, n = 20). Perioperative variables were compared between the two groups.

Results

There were no significant differences in patient characteristics between the two groups. During the first 24 h after intensive care unit admission, heart rate and serum lactate levels were significantly lower in the dexmedetomidine group compared to the control group ( p = 0.0292 and p = 0.0027, respectively). The maximal midazolam dose was also significantly lower in the dexmedetomidine group (0.12 ± 0.09 vs. 0.20 ± 0.08 mg kg−1 h−1, p = 0.0059). There were no adverse effects of dexmedetomidine such as bradycardia, hypotension, agitation, or seizures. Three (15%) patients in the control group and none in the dexmedetomidine group experienced sudden cardiopulmonary decompensation.

Conclusions

Dexmedetomidine can provide favorable sedative properties with a reduced requirement for concomitant midazolam and stable hemodynamics with tachycardia prevention, for postoperative intensive care following pediatric cardiac surgery.

Effects of Clonidine on Withdrawal From Long-term Dexmedetomidine in the Pediatric Patient

OBJECTIVE

To compare withdrawal symptoms among pediatric intensive care patients receiving clonidine to those not receiving clonidine while being weaned from long-term dexmedetomidine.

METHODS

This retrospective analysis evaluated Withdrawal Assessment Tool-1 (WAT-1) scores and hemodynamic parameters in pediatric patients on dexmedetomidine for 5 days or longer between January 1, 2009, and December 31, 2012. The primary objective was to compare withdrawal symptoms based on the number of elevated WAT-1 scores among patients on clonidine to those not on clonidine, while being weaned from long-term dexmedetomidine. The secondary objective was to describe withdrawal symptoms associated with long-term dexmedetomidine use.

RESULTS

Nineteen patients (median age, 1.5 years; interquartile range [IQR], 0.67-3.3) received 20 treatment courses of dexmedetomidine for at least 5 days. Clonidine was received by patients during 12 of the treatment courses. The patients in the clonidine group had an average of 0.8 (range, 0-6) elevated WAT-1 scores 24 hours post wean compared to an average of 3.2 (0-8) elevated WAT-1 scores in the no clonidine group (p = 0.49). There were no significant difierences between prewean and postwean systolic or diastolic blood pressures among the 2 groups. The average heart rate during the postwean period was 112 beats per minute (bpm) (range, 88.5-151.5) in the clonidine group compared to 138.4 bpm (range, 117.8-168.3) in the no clonidine group (p = 0.003). In the clonidine group, the mean change in heart rate postwean compared to prewean was an increase of 3.6 bpm (range, -39.6 to 47.5), compared to a mean increase of 29.9 bpm (range, 5.5-74.7) in the no clonidine group (p = 0.042).

CONCLUSIONS

There was no difierence in WAT-1 scores between groups, with the clonidine group displaying a trend towards fewer elevated WAT-1 scores during the 24 hours post dexmedetomidine wean. Patients who received clonidine had significantly lower heart rates than the no clonidine group.

Retrospective Evaluation of the Epidemiology and Practice Variation of Dexmedetomidine Use in Invasively Ventilated Pediatric Intensive Care Admissions, 2007-2013

OBJECTIVES

The study assessed dexmedetomidine utilization and practice variation over time in ventilated pediatric intensive care unit (PICU) patients; and evaluated differences in hospital outcomes between high- and low-dexmedetomidine utilization hospitals.

STUDY DESIGN

This serial cross-sectional analysis used administrative data from PICU admissions in the pediatric health information system (37 US tertiary care pediatric hospitals). Included admissions from 2007 to 2013 had simultaneous dexmedetomidine and invasive mechanical ventilation charges, <18 years of age, excluding neonates. Patient and hospital characteristics were compared as well as hospital-level severity-adjusted indexed length of stay (LOS), charges, and mortality.

RESULTS

The utilization of dexmedetomidine increased from 6.2 to 38.2 per 100 ventilated PICU patients among pediatric hospitals. Utilization ranged from 3.8 to 62.8 per 100 in 2013. Few differences in patient demographics and no differences in hospital-level volume/severity of illness measures between high- and low-utilization hospitals occurred. No differences in hospital-level, severity-adjusted indexed outcomes (LOS, charges, and mortality) were found.

CONCLUSION

Wide practice variation in utilization of dexmedetomidine for ventilated PICU patients existed even as use has increased sixfold. Higher utilization was not associated with increased hospital charges or reduced hospital LOS. Further work should define the expected outcome benefits of dexmedetomidine and its appropriate use.

Long-term dexmedetomidine use and safety profile among critically ill children and neonates

OBJECTIVE

To determine whether long-term dexmedetomidine dosing is associated with lower opioid and benzodiazepine use without risk of significant hemodynamic changes and/or withdrawal.

DESIGN

Retrospective, observational study.

SETTING

PICU, cardiovascular ICU, and neonatal ICU in a single, tertiary care, academic children's hospital.

SUBJECTS

We included all patients less than or equal to 21 years old, who received dexmedetomidine for greater than or equal to 72 hours from December 2008 to December 2010 resulting in a 98-subject cohort.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

The median duration of dexmedetomidine use was 141 hours. A decrease in systolic blood pressure and heart rate was seen after initiation of dexmedetomidine. After dexmedetomidine was discontinued, systolic blood pressure was statistically significantly higher than baseline. Similarly, heart rate showed a significant increase from baseline following discontinuation of dexmedetomidine. Starting dexmedetomidine was not associated with a significant difference in the dosing of opiates or benzodiazepines. Comfort scores were significantly lower at 2 and 72 hours of dexmedetomidine infusion. After stopping dexmedetomidine, the comfort score for patients at 1 hour was statistically higher than for patients at cessation of the infusion. Thirty percent of patients who were taken off dexmedetomidine, whether weaned or abruptly stopped, had withdrawal symptoms and scores recorded with agitation, tremor, and decreased sleep being most prominent.

CONCLUSIONS

Hemodynamic effects of dexmedetomidine did not limit long-term use in this diverse population. After the addition of dexmedetomidine, opioid and benzodiazepine doses did not significantly escalate, and patients were more comfortable as evidenced by decreasing comfort scores. Withdrawal from dexmedetomidine may be an issue and manifests as agitation, tremors, and decreased sleep.

Dexmedetomidine attenuates hypoxemia during palliative reconstruction of the right ventricular outflow tract in pediatric patients

The objective of this study was to investigate whether the α agonist dexmedetomidine has the ability to attenuate hypoxemia in pediatric patients undergoing palliative pulmonary artery reconstruction.From January 2009 to January 2013, a total of 25 pediatric patients with Tetralogy of Fallot, pulmonary atresia (ventricular septal defect), or persistent truncus arteriosus (I) were enrolled in our study. Due to hypoplastic pulmonary arteries, all patients received palliative pulmonary artery reconstruction. During the perioperative period, they were allocated to receive either dexmedetomidine (bolus dose of 0.3 μg/kg followed by an infusion of 0.2-0.3 μg/kg/h, n = 15) or control drug (n = 10) intravenously. Any desaturation was recorded. Heart rate, mean arterial pressure, pulse oximetry, and arterial blood gas parameters were measured during the perioperative period.There were no significant differences between the groups in hemodynamic variables. The arterial oxygen saturation and arterial blood gas parameters increased in the dexmedetomidine groups (P < 0.05).These findings suggest that the injection of dexmedetomidine can attenuate hypoxemia during palliative pulmonary artery reconstruction in pediatric patients.

The pharmacologic management of delirium in children and adolescents

Delirium is a serious and common problem in severely medically ill patients of all ages. It has been less addressed in children and adolescents. Treatment of delirium is predicated on addressing its underlying cause. The management of its symptoms depends on the off-label use of antipsychotics, while avoiding agents that precipitate or worsen delirium. Olanzapine, quetiapine, and risperidone are presently considered first-line drugs, usually replacing haloperidol. Other agents have shown promise, including melatonin to address the sleep disturbance characteristic of delirium, and dexmedetomidine, an α2-agonist, that may facilitate lower doses of benzodiazepines and opioids that may worsen delirium.

Cardiovascular Effects of Continuous Dexmedetomidine Infusion Without a Loading Dose in the Pediatric Intensive Care Unit

BACKGROUND

Use of dexmedetomidine in pediatric critical care is common, despite lack of prospective studies on its hemodynamic effects.

OBJECTIVE

To describe cardiovascular effects in critically ill children treated with a constant continuous infusion of dexmedetomidine without a loading dose at highest Food and Drug Administration-approved adult dose.

METHODS

Prospective, pilot study of 17 patients with dexmedetomidine infused at a rate of 0.7 μg/kg/h for 6 to 24 hours. Heart rate (HR) and blood pressure (BP) values over time were analyzed by a random effects mixed model.

RESULTS

Patients with median age of 1.6 years (1 month to 17 years) and median weight of 11.8 kg (2.8-84 kg) received an infusion for a mean of 16 ± 7.2 hours. There were no cardiac conduction abnormalities. One patient required discontinuation of infusion for predetermined low HR termination criteria at hour 13 of infusion; there was no clinical compromise and it coincided with planned extubation. Decreased HR of 20% from baseline was found in 35% of patients. The mean HR reduction was largest at hour 13 of infusion with a decrease of 13 ± 17 bpm from baseline, but HR changes over time were not statistically significant. Blood pressure effects included a decrease in 12% and an increase in 29%. There was a small but statistically significant increase in systolic BP of 0.4 mm Hg/h of infusion, P < .001.

CONCLUSION

A continuous infusion of 0.7 μg/kg/h of dexmedetomidine without a loading dose for up to 24 hours in critically ill children had tolerable effects on HR and BP.

Dexmedetomidine infusion associated with transient adrenal insufficiency in a pediatric patient: a case report

Dexmedetomidine is a highly selective α₂-adrenoceptor agonist used for sedation due to its anxiolytic and analgesic properties without respiratory compromise. Due to its structural similarity to etomidate, there has been concern that dexmedetomidine may cause adrenal insufficiency. This concern was initially supported by animal studies, but subsequent human studies demonstrated mixed results. We describe the case of transient adrenal insufficiency in a 1-year-old male who presented with 24% total body surface 2nd degree burns. He required sedation with a prolonged, high-dose dexmedetomidine infusion with a peak infusion dose of 2.7 mcg/kg/hr and duration of 6.5 days. The patient developed lethargy and hypotension four days after discontinuation of his infusion. He had a random cortisol level which was low at 0.4 mcg/dL, and the concern for adrenal suppression was confirmed with an ACTH stimulation test with the baseline cortisol of 0.4 mcg/dL and inappropriate 60 minute post-ACTH stimulation cortisol of 7.8 mcg/dL. While further studies will be needed to clarify the risk of adrenal suppression secondary to dexmedetomidine, this case suggests that caution should be taken when administering dexmedetomidine to pediatric patients and highlights the need for future studies to look at appropriate dosing and duration of dexmedetomidine infusions.

Safety and efficacy of dexmedetomidine in children with heart failure

This retrospective observational study aimed to evaluate the safety and efficacy of dexmedetomidine (DEX) for children with heart failure. The study was conducted in the cardiovascular intensive care unit (CVICU) of a single, tertiary care, academic children's hospital. A retrospective review of the charts for all children (up to 18 years of age) with signs and symptoms consistent with congestive heart failure who received DEX in our CVICU between April 2006 and April 2011 was performed. The patients were divided into two groups for study purposes: the DEX group of 21 patients, who received a DEX infusion together with other conventional sedation agents, and the control group of 23 patients, who received conventional sedation agents without the use of DEX. To evaluate the safety of DEX, physiologic data were collected including heart rate, mean arterial pressure (MAP), and inotrope score. To assess the efficacy of DEX, the amount and duration of concomitant sedation and analgesic infusions in both the DEX and control groups were examined. The numbers of rescue boluses for each category before the initiation of sedative infusion and during the sedative infusion also were examined. The baseline characteristics of the patients in the two groups were similar. There was no effect of DEX infusion on heart rate, MAP, or inotrope score at the termination of infusion. The daily amount of midazolam administered was significantly less during the last 24 h of DEX infusion in the DEX group than in the control group (p = 0.04). The daily amount of morphine infusion did not differ between the DEX and control groups during any period. The numbers of sedation and analgesic rescue boluses were lower in DEX group throughout the infusion. No other significant side effects were noted. Two patients in the DEX group had a 50 % or greater drop in MAP compared with baseline in the first 3 h after initiation of DEX infusion, whereas one patient had a 50 % or greater drop in heart rate compared with baseline in the first 3 h after initiation of DEX infusion. Administration of DEX for children with heart failure appears to be safe but should be used cautiously. Furthermore, DEX use is associated with a decreased opiate and benzodiazepine requirement for children with heart failure.

The role of systematic reviews in pharmacovigilance planning and Clinical Trials Authorisation application: example from the SLEEPS trial

BACKGROUND

Adequate sedation is crucial to the management of children requiring assisted ventilation on Paediatric Intensive Care Units (PICU). The evidence-base of randomised controlled trials (RCTs) in this area is small and a trial was planned to compare midazolam and clonidine, two sedatives widely used within PICUs neither of which being licensed for that use. The application to obtain a Clinical Trials Authorisation from the Medicines and Healthcare products Regulatory Agency (MHRA) required a dossier summarising the safety profiles of each drug and the pharmacovigilance plan for the trial needed to be determined by this information. A systematic review was undertaken to identify reports relating to the safety of each drug.

METHODOLOGY/PRINCIPAL FINDINGS

The Summary of Product Characteristics (SmPC) were obtained for each sedative. The MHRA were requested to provide reports relating to the use of each drug as a sedative in children under the age of 16. Medline was searched to identify RCTs, controlled clinical trials, observational studies, case reports and series. 288 abstracts were identified for midazolam and 16 for clonidine with full texts obtained for 80 and 6 articles respectively. Thirty-three studies provided data for midazolam and two for clonidine. The majority of data has come from observational studies and case reports. The MHRA provided details of 10 and 3 reports of suspected adverse drug reactions.

CONCLUSIONS/SIGNIFICANCE

No adverse reactions were identified in addition to those specified within the SmPC for the licensed use of the drugs. Based on this information and the wide spread use of both sedatives in routine practice the pharmacovigilance plan was restricted to adverse reactions. The Clinical Trials Authorisation was granted based on the data presented in the SmPC and the pharmacovigilance plan within the clinical trial protocol restricting collection and reporting to adverse reactions.

Safety and Effectiveness of Dexmedetomidine in the Pediatric Intensive Care Unit (SAD-PICU)

BACKGROUND

Critically ill children require sedation for comfort and to facilitate mechanical ventilation and interventions. Dexmedetomidine is a newer sedative with little safety data in pediatrics, particularly for therapy lasting longer than 48 h.

OBJECTIVE

To quantify the frequency of adverse events and withdrawal syndromes associated with dexmedetomidine and to describe the use of this drug for continuous sedation in critically ill children.

METHODS

In this retrospective study of patients who received dexmedetomidine for sedation in the pediatric intensive care unit, adverse events were assessed with the Naranjo scale to determine the likelihood of association with dexmedetomidine. Interventions in response to adverse events were also recorded.

RESULTS

One hundred and forty-four patients (median age 34 months, range 0 - 17.7 years) who underwent a total of 153 treatment courses were included. The mean infusion rate of dexmedetomidine was 0.42 μg/kg per hour (standard deviation 0.17 μg/kg per hour, range 0.05-2 μg/kg per hour). The median duration of therapy was 20.50 h (range 0.75-854.75 h), and 70 infusions (46%) lasted more than 24 h. At least one adverse event was observed in 115 (75%) of the treatment courses. Hypotension (81 [53%]) and bradycardia (38 [25%]) were the most common adverse events and were deemed "probably" attributable to dexmedetomidine in 17 (11%) and 9 (6%) of the treatment courses, respectively. In 55 of the 66 treatment courses with infusions lasting longer than 24 h for which post-infusion data were available, at least one withdrawal symptom was observed; agitation (41 [62%]) and hypertension (22 [33%]) were the most common withdrawal symptoms.

CONCLUSIONS

Dexmedetomidine was commonly administered for longer than 24 h in the authors' institution. Dexmedetomidine was generally well tolerated; however, the majority of patients experienced withdrawal symptoms. Patients receiving dexmedetomidine for more than 24 h should be monitored for withdrawal following discontinuation, and interventions should be provided if needed. Prospective, controlled studies are needed to characterize the safety of long-term dexmedetomidine therapy in critically ill children.

Safety and efficacy of prolonged dexmedetomidine use in critically ill children with heart disease*

OBJECTIVES

To evaluate the safety and efficacy of prolonged dexmedetomidine administration (≥ 96 hrs) in critically ill children with heart disease.

DESIGN

Retrospective observational study.

SETTING

Cardiovascular intensive care unit in a single, tertiary care, academic children's hospital.

INTERVENTIONS

None.

SUBJECTS

We conducted a retrospective review of the charts of all critically ill infants and children (up to 18 yrs of age) with congenital or acquired heart disease who received dexmedetomidine for ≥ 96 hrs in our pediatric cardiovascular intensive care unit between January 2009 and March 2010. Patients were divided into two groups for study purposes: the dexmedetomidine group (n = 52) included patients who received a dexmedetomidine infusion along with other conventional sedation agents, and the control group (n = 42) included patients who received conventional sedation agents without the use of dexmedetomidine. Clinical outcomes evaluated in our study included days of mechanical ventilation, cardiovascular intensive care unit length of stay, hospital length of stay, and mortality. To evaluate the safety of dexmedetomidine, we collected physiologic data, including heart rate, mean arterial pressure, respiratory rate, systemic oxygen saturation by pulse oximetry, and inotrope score. To assess the efficacy of dexmedetomidine, we examined the amount and duration of concomitant sedation and analgesic infusions over a period of 24 hrs in both dexmedetomidine and control groups. We also examined the number of rescue boluses for each category prior to the initiation of sedative infusion, during the sedative infusion, and after the termination of the sedative infusion. The potential side effects evaluated in our study included nausea, vomiting, abdominal distension, dysrhythmias, neurological abnormalities, seizures, and signs and symptoms of withdrawal.

MEASUREMENTS AND MAIN RESULTS

Patients' baseline characteristics were similar in the two groups. Patient complexity as measured by Risk-Adjusted Classification for Congenital Heart Surgery-1 score, ventricular ejection fraction, and proportion of patients receiving mechanical ventilatory support at the time of initiation of sedative infusion was also similar. The duration and amount of continuous midazolam and morphine infusions were significantly lower in the dexmedetomidine group when compared to the control group. During dexmedetomidine infusion, there was no statistical difference in the heart rate and blood pressure between the two groups. Inotrope score was significantly lower in the dexmedetomidine group as compared to the control group in the last 6 hrs prior to termination of dexmedetomidine infusion (p < .001), and at 1 hr (p < .001) and 6 hrs (p < .001) after termination of dexmedetomidine infusion. There was no difference in duration of mechanical ventilation (p = .77), cardiovascular intensive care unit length of stay (p = .29), or hospital length of stay (p = .43) in the two groups. One patient experienced junctional rhythm at 130 beats/min requiring temporary pacing. No other significant side effects were noted. A higher proportion of patients in the dexmedetomidine group were administered clonidine when compared to the control group after termination of dexmedetomidine (31% vs. 7%, p = .005).

CONCLUSIONS

Prolonged dexmedetomidine administration in children with heart disease appears to be safe and is associated with decreased opioid and benzodiazepine requirement and decreased inotropic support.

Hemodynamic effects of dexmedetomidine in critically ill neonates and infants with heart disease

The primary objective of this study was to evaluate the hemodynamic effects of dexmedetomidine (DEX) infusion on critically ill neonates and infants with congenital heart disease (CHD). The secondary objective of the study was to evaluate the safety and efficacy profile of the drug in this patient population. A retrospective observational study was conducted in the cardiovascular intensive care unit (CVICU) of a single tertiary care university children's hospital. The charts of all neonates and infants who received DEX in the authors' pediatric CVICU between August 2009 and June 2010 were retrospectively reviewed. The demographic data collected included age, weight, sex, diagnosis, and Risk Adjustment in Congenital Heart Surgery (RACHS-1) score. To evaluate the hemodynamic effects of DEX, physiologic data were collected including heart rate, mean arterial pressure (MAP), inotrope score, near-infrared spectroscopy, and central venous pressure (CVP). To assess the efficacy of DEX, the amount and duration of concomitant sedation and analgesic infusions over a period of 24 h were examined together with the number of rescue boluses. The potential side effects evaluated in this study included nausea, vomiting, abdominal distension, dysrhythmias, neurologic abnormalities, seizures, and signs and symptoms of withdrawal. During the study period, 50 neonates and infants received DEX for a median period of 78 h (range, 40-290 h). These patients had an average age of 3.53 ± 2.64 months and a weight of 4.85 ± 1.67 kg. Whereas 34 patients (68%) received DEX after surgery for CHD, 15 patients (30%) received DEX after heart transplantation. Of these 50 infants, 10 (20%) had a single-ventricle anatomy, whereas 13 (26%) had a risk adjustment score (RACHS-1) in the category of 4-6. The median CVICU stay was 29 days (range, 8-69 days). Despite a significant decrease in heart rate, MAP, inotrope score, and CVP, all the patients remained hemodynamically stable during DEX infusion. There was no substantial difference in major hemodynamic variables between neonates and infants, single- and two-ventricle repair, RACHS 4-6 and RACHS 1-3 categories for patients undergoing surgery, or patients undergoing heart transplantation and patients undergoing other surgical procedures. Dexmedetomidine infusion for neonates and infants with heart disease is safe from a hemodynamic standpoint and can reduce the concomitant dosing of opioid and benzodiazepine agents. Furthermore, DEX infusion may be useful for reducing vasopressor agent dosing in children with catecholamine-refractory cardiogenic shock.

Dexmedetomidine versus standard therapy with fentanyl for sedation in mechanically ventilated premature neonates

OBJECTIVE

To compare the efficacy and safety of dexmedetomidine and fentanyl for sedation in mechanically ventilated premature neonates.

METHODS

This was a retrospective, observational case-control study in a level III neonatal intensive care unit. Forty-eight premature neonates requiring mechanical ventilation were included. Patients received fentanyl (n=24) or dexmedetomidine (n=24) for pain or sedation. Each group also received fentanyl and lorazepam boluses as needed for agitation. The primary outcomes were efficacy and frequency of acute adverse events associated with each drug. Days on mechanical ventilation, stooling patterns, feeding tolerance, and neurologic outcomes were also evaluated.

RESULTS

There were no significant differences in baseline demographics between the dexmedetomidine and fentanyl patients. Patients in the dexmedetomidine group required less adjunctive sedation and had more days free of additional sedation in comparison to fentanyl (54.1% vs. 16.5%, p<0.0001). There were no differences in hemodynamic parameters between the 2 groups. Duration of mechanical ventilation was shorter in the dexmedetomidine group (14.4 vs. 28.4 days, p<0.001). Meconium passage (7.5 vs. 22.4 days, p<0.0002) and time from initiation to achievement of full enteral feeds (26.8 vs. 50.8 days, p<0.0001) were shorter in the dexmedetomidine group. Incidence of culture-positive sepsis was lower in the dexmedetomidine group (48% vs. 88%). The incidence of either severe intraventricular hemorrhage or periventricular leukomalacia was not statistically significantly reduced (2% vs. 7%).

CONCLUSIONS

Dexmedetomidine was safe and effective for sedation in the premature neonates included in this study. Prospective randomized-controlled trials are needed before routine use of dexmedetomidine can be recommended.

Dexmedetomidine hydrochloride as a long-term sedative

Dexmedetomidine undoubtedly is a useful sedative in the intensive care setting because it has a minimal effect on the respiratory system. Dexmedetomidine infusions lasting more than 24 hours have not been approved since the first approval was acquired in the US in 1999. However, in 2008, dexmedetomidine infusions for prolonged use were approved in Colombia and in the Dominican Republic, and the number of countries that have granted approval for prolonged use has been increasing every year. This review discusses the literature examining prolonged use of dexmedetomidine and confirms the efficacy and safety of dexmedetomidine when it is used for more than 24 hours. Dexmedetomidine was administered at varying doses (0.1–2.5 μg/kg/hour) and durations up to 30 days. Dexmedetomidine seems to be an alternative to benzodiazepines or propofol for achieving sedation in adults because the incidences of delirium and coma associated with dexmedetomidine are lower than the corresponding incidences associated with benzodiazepines and propofol, although dexmedetomidine administration can cause mild adverse effects such as bradycardia. Controlled comparative studies on the efficacy and safety of dexmedetomidine and other sedatives in pediatric patients have not been reported. However, dexmedetomidine seems to be effective in managing extubation, reducing the use of conventional sedatives, and as an alternative for inducing sedation in patients for whom traditional sedatives induce inadequate sedation. Prolonged dexmedetomidine infusion has not been reported to have any serious adverse effects. Dexmedetomidine appears to be an alternative long-term sedative, but further studies are needed to establish its efficacy and safety.

Use of dexmedetomidine for sedation in critically ill mechanically ventilated pediatric burn patients

Dexmedetomidine has previously been used only for short-term, procedural sedation in children. The purpose of this review was to describe the dosing, safety, and efficacy of dexmedetomidine for sustained sedation in intubated pediatric burn patients. The authors reviewed acutely burned children treated between 2005 and 2008 who were intubated during their course of care and who received dexmedetomidine for sedation. Patients served as their own controls using the time periods when they received sedatives other than dexmedetomidine. Eleven patients with 17 dexmedetomidine treatment courses were identified. The median patient age was 7 years (range 1.6-17 years), and median burn size was 30.5% TBSA (range 6-59%). Patients were ventilated for a median of 9 days (range 4-46 days). The median initial dose of dexmedetomidine was 0.39 μg/kg/hr (range 0.10-1.16 μg/kg/hr), with a median infusion dose of 0.57 μg/kg/hr (range 0.11-1.17 μg/kg/hr) and median treatment duration of 40 hours (range 1-356 hours). None of the patients received dexmedetomidine loading dose. Patients achieved more appropriate Riker scores while treated with dexmedetomidine than while being treated with other sedatives (3.8 vs 3.3, P = .003). The incidence of hypotension and/or bradycardia while on dexmedetomidine was not greater than when it was not being used. Clinically significant rebound hypertension and tachycardia were absent on discontinuation of dexmedetomidine. No unplanned extubations were observed. Median length of hospital stay was 49 days (range 7-118 days). Dexmedetomidine seems to be safe and effective for sedation of pediatric burn patients on mechanical ventilation with close cardiovascular monitoring.

Optimal timing for the administration of intranasal dexmedetomidine for premedication in children

Previous studies have shown that 1 μg.kg(-1) intranasal dexmedetomidine produces significant sedation in children aged between 2 and 12 years. This investigation was designed to evaluate the onset time. One hundred children aged 1-12 years of ASA physical status 1-2 undergoing elective surgery were randomly allocated to five groups. Patients in groups A to D received intranasal dexmedetomidine 1 μg.kg(-1) . Patients in Group E received intranasal placebo (0.9% saline). Children from groups A, B, C, D and E had intravenous cannulation attempted at 30, 45, 60, 75 and 45 min respectively after intranasal drug or placebo administration. Vital signs, behaviour and sedation status of the children were assessed regularly until induction of anaesthesia. More children from groups A to D achieved satisfactory sedation at the time of cannulation when compared to group E (p < 0.001). The proportion of children who achieved satisfactory sedation was not significantly different among groups A to D. Overall 62% of the children who received intranasal dexmedetomidine had satisfactory sedation at the time of cannulation. The median (95% CI) time for onset of sedation was 25 (25-30) min. The median (95% CI) duration of sedation was 85 (55-100) min.

Dexmedetomidine use in pediatric airway reconstruction

OBJECTIVE

Assess the postoperative use of dexmedetomidine (Precedex) in pediatric patients following airway reconstruction.

STUDY DESIGN

Historical cohort study.

SETTING

Tertiary medical center.

SUBJECTS AND METHODS

A retrospective review of 24 children undergoing laryngotracheal reconstruction (LTR) or laryngeal cleft repair (LCR) was conducted. Twelve children were treated with standard sedation protocols where dexmedetomidine was administered in lieu of propofol (Diprivan); 12 age-, gender-, and procedure-matched controls were selected. Subjects were divided into groups based on duration of postoperative intubation for cross-comparison; group 1 was intubated <24 hours, group 2 was intubated 2 to 6 days, and group 3 was intubated 7 days or longer. Baseline heart rate and blood pressure measurements were compared to hourly measurements for the first 6 hours following initiation of dexmedetomidine or mechanical ventilation in the control group. Number of supportive respiratory interventions, adverse events, self-extubations, premature termination of dexmedetomidine, amount of muscle relaxants, agents to treat withdrawal, and length of stay were evaluated.

RESULTS

Ten patients undergoing LTR and 2 patients undergoing LCR receiving dexmedetomidine were compared to 10 LTR and 2 LCR control patients. Overall, dexmedetomidine was well tolerated and without significant adverse effects, particularly in cases of short-term intubation or as a bridge to extubation.

CONCLUSION

In cases requiring short-term intubation following airway reconstruction, dexmedetomidine may offer a safe alternative to propofol by providing readily reversible sedation during the periextubation period. Further studies are needed to determine the safety, efficacy, dosing, and potential complications of longer term dexmedetomidine administration in pediatric airway reconstruction.

Prolonged infusions of dexmedetomidine in critically ill patients

PURPOSE

The efficacy and safety of dexmedetomidine when used longer than the manufacturer-recommended 24 hours were evaluated.

SUMMARY

Dexmedetomidine is the newest agent available for use in the critical care setting to induce and maintain sedation and analgesia. However, concerns over efficacy and safety during prolonged administration are a limiting factor for use in this patient population. A literature review was conducted to assess the clinical evidence regarding the efficacy and safety of dexmedetomidine for longer than 24 hours. A total of 11 studies were identified. Of these trials, 6 included adult patients and 5 included pediatric patients. Of the 6 adult trials, 3 comparative trials demonstrated a similar efficacy with benzodiazepines (i.e., midazolam and lorazepam) or propofol, with a reduction in the incidence of delirium and coma associated with dexmedetomidine. In noncomparative trials, dexmedetomidine was efficacious in achieving sedation goals with only mild adverse effects. In the 5 pediatric trials evaluated, efficacy to achieve a target sedation scale score could not be assessed, as most studies did not use validated sedation scales to measure goal sedation. Alternatively, the safety of dexmedetomidine has been demonstrated throughout an extended duration of use. In all of the studies evaluated, dexmedetomidine was associated with bradycardia; however, there were no reports of withdrawal effects, including rebound tachycardia and hypertension, upon discontinuation of dexmedetomidine infusion.

CONCLUSION

Dexmedetomidine is an alternative to traditional sedatives and analgesics in critically ill patients. The safety and efficacy of dexmedetomidine in adults likely persist beyond 24 hours, without the emergence of rebound effects after discontinuation.

Dexmedetomidine Use in Pediatric Intensive Care and Procedural Sedation

OBJECTIVE

Dexmedetomidine was approved by the Food and Drug Administration in 1999 for the sedation of adults receiving mechanical ventilation in an intensive care setting. It provides sedation with minimal effects on respiratory function and may be used prior to, during, and following extubation. Based on its efficacy in adults, dexmedetomidine is now being explored as an alternative or adjunct to benzodiazepines and opioids in the pediatric intensive care setting. This review describes the studies evaluating the safety and efficacy dexmedetomidine in infants and children and provides recommendations on dosing and monitoring.

METHODS

The MEDLINE (1950–November 2009) database was searched for pertinent abstracts, using the key term dexmedetomidine. Additional references were obtained from the bibliographies of the articles reviewed and the manufacturer. All available English-language case reports, clinical trials, retrospective studies, and review articles were evaluated.

RESULTS

Over two dozen case series and clinical studies have documented the utility of dexmedetomidine as a sedative in children requiring mechanical ventilation or procedural sedation. In several papers, dexmedetomidine use resulted in a reduction in the dose or discontinuation of other sedative agents. It may be of particular benefit in children with neurologic impairment or in those who do not tolerate benzodiazepines. The most frequent adverse effects reported with dexmedetomidine have been hypotension and bradycardia, in 10% to 20% of patients. These effects typically resolve with dose reduction.

CONCLUSIONS

Dexmedetomidine offers an additional choice for the sedation of children receiving mechanical ventilation in the intensive care setting or requiring procedural sedation. While dexmedetomidine is well tolerated when used at recommended doses, it has the potential to cause hypotension and bradycardia and requires close monitoring. In addition to clinical trials currently underway, larger controlled studies are needed to further define the role of dexmedetomidine in pediatric intensive care.

Neurologic Withdrawal Symptoms Following Abrupt Discontinuation of a Prolonged Dexmedetomidine Infusion in a Child

Dexmedetomidine is a α2-adrenergic agonist which possesses sedative, analgesic, and anxiolytic properties. It is approved for short-term use in adults to provide sedation while mechanically ventilated and for noninvasive procedural sedation. An increased number of anecdotal reports describe the use dexmedetomidine in children. Cardiovascular withdrawal symptoms have been reported in the literature. However, there have been few published reports of neurologic withdrawal symptoms following discontinuation of prolonged infusions of dexmedetomidine. We describe a 2 year-old child who received a prolonged continuous infusion (263 hours) of dexmedetomidine as an adjunctive sedative agent. Following abrupt discontinuation of dexmedetomidine, the patient presented with symptoms suggestive of neurological withdrawal. The symptoms gradually resolved over two days without further intervention, and the patient had full resolution of symptoms and was discharged home with no further neurologic sequelae.

Evaluation of Adverse Events Noted in Children Receiving Continuous Infusions of Dexmedetomidine in the Intensive Care Unit

OBJECTIVES

Dexmedetomidine is an α2-adrenergic receptor agonist with sedative and analgesic effects in mechanically ventilated adults and children. Safety and efficacy data are limited in children. The purpose of this study is to retrospectively identify the incidence and types of adverse events noted in children receiving continuous infusions of dexmedetomidine and evaluate potential risk factors for adverse events.

METHODS

Between July 1, 2006, and July 31, 2007, data were collected on all children (&lt; 18 years) who received continuous infusions of dexmedetomidine. Data collection included demographics, dexmedetomidine regimen, and type/number of adverse events. The primary endpoint was the total number of adverse events noted, including: transient hypertension, hypotension, neurological manifestations, apnea, and bradycardia. Secondary endpoints included categorization of each type of adverse event and an assessment of risk factors. A logistic regression model was used to assess the relationship of adverse events with independent variables including length of ICU stay, cumulative dose, peak infusion rate, duration of therapy, PRISM III score, and bolus dose.

RESULTS

Thirty-six patients received dexmedetomidine representing 41 infusions. The median age was 16 months (range, 0.1–204 months) and median PRISM III score was 2 (range, 0–18). Eighteen (43.9%) patients received a bolus dose of dexmedetomidine. The median cumulative dose (mcg/kg) and peak dose (mcg/kg/hr) were 8.5 (range, 2.2–193.7) and 0.5 (range, 0.2–0.7), respectively. Dexmedetomidine was continued for a median of 20 (range, 3–263) hours. Six (14.6%) patients were slowly tapered off the continuous infusions. Twenty-one adverse events were noted in 17 patients, including 4 neurologic manifestations. Fourteen patients required interventions for adverse events. ICU length of stay was the only independent risk factor (p=0.036) for development of adverse events.

CONCLUSIONS

Several potential adverse events were noted with dexmedetomidine continuous infusions including possible neurological manifestations. Further studies are needed looking at adverse events associated with dexmedetomidine use in the pediatric population.

A new dosing protocol reduces dexmedetomidine-associated hypotension in critically ill surgical patients

BACKGROUND

Although no ideal sedative exists, dexmedetomidine is unique because it produces sedation and analgesia without decreasing the respiratory drive. Hemodynamic responses to dexmedetomidine are variable and dependent on the patient population. Our initial experience was associated with an unacceptable incidence of hypotension and bradycardia. We evaluated occurrence of hypotension and bradycardia in critically ill surgical patients receiving dexmedetomidine before and after implementation of a dosing protocol.

METHODS

This is a retrospective chart review of all admissions to a university medical center-based, 44-bed surgical intensive care unit pre and post protocol implementation.

RESULTS

Forty-four patients received dexmedetomidine including 19 historic controls and 25 dosed via protocol. Both groups had comparable demographics and initial and maximum dosages of dexmedetomidine. Use of the dosing protocol resulted in fewer dosage changes (mean +/- standard deviation, 4.8 +/- 3.8 compared to 7.8 +/- 3.9; P = .014) and fewer episodes of hypotension (16% vs 68.4%; P = .0006) but did not influence bradycardic episodes (20% vs 15.5%; P > .99).

CONCLUSION

We found that use of a protocol that increases the time interval between dosage adjustments may reduce dexmedetomidine-associated hypotension.

Dexmedetomidine sedation for pediatric post-Fontan procedure patients

OBJECTIVE

The hemodynamic, respiratory, and sedative effects of dexmedetomidine (DEX) for pediatric patients post-Fontan surgery.

DESIGN

Retrospective.

SETTING

Single institutional intensive care unit.

PARTICIPANTS

Fourteen patients undergoing Fontan-type surgery.

RESULT

A retrospective review was conducted on 14 pediatric patients who had undergone a Fontan procedure for congenital heart disease. A vital component of postoperative management of these patients is to prevent an increase in pulmonary vascular resistance (PVR) that may lead to a serious reduction in cardiac output. DEX an alpha-2 adrenergic receptor agonist might offer an advantage over current sedation methods in preventing a rise in PVR. Nine patients received sedation with DEX and five patients in a control group were administered standard regimens of sedation and analgesia. The DEX group exhibited no evidence of an increased partial pressure of arterial carbon dioxide postoperatively as opposed to the control group. This lack of respiratory depression made the DEX group less likely to increase their PVR. However, the DEX group did experience a significant incidence of bradycardia that required the use of a cardiac pacemaker.

CONCLUSIONS

The results of this retrospective review of the role of DEX in the management of the post-Fontan surgical pediatric patient indicate some potential advantages.

Efficacy of sedation regimens to facilitate mechanical ventilation in the pediatric intensive care unit: a systematic review

OBJECTIVE

Children admitted to pediatric intensive care units (PICUs) often receive sedatives to facilitate mechanical ventilation. However, despite their widespread use, data supporting appropriate dosing, safety, and optimal regimens for sedation during mechanical ventilation are lacking. Therefore, we conducted a systematic review of published data regarding efficacy of sedation to facilitate mechanical ventilation in PICU patients. Our primary objective was to identify and evaluate the quality of evidence supporting sedatives used in PICUs for this purpose.

DATA SOURCES

We searched MEDLINE, EMBASE, and The Cochrane Registry of Clinical Trials from 1966 to June 2008 to identify published articles evaluating sedation regimens to facilitate mechanical ventilation in PICU patients.

STUDY SELECTION

We included only those studies of intubated PICU or pediatric cardiac intensive care unit patients receiving pharmacologic agents to facilitate mechanical ventilation that reported quality of sedation as an outcome.

DATA EXTRACTION

We analyzed studies separately for study type and by agents being studied. Studies were appraised using criteria of particular importance for reviews evaluating sedatives.

DATA SYNTHESIS

Our search strategy yielded 39 studies, including 3 randomized trials, 15 cohort studies, and 21 cases series or reports. The 39 studies evaluated a total of 39 different sedation regimens, with 21 different scoring systems, in a total of 901 PICU/cardiac intensive care unit patients ranging in age from 3 days to 19 years old. Most of the studies were small (<30 patients), and only four studies compared one or more agents to another. Few studies thoroughly evaluated drug safety, and only one study met all quality criteria.

CONCLUSIONS

Despite the widespread use of sedatives to facilitate mechanical ventilation in the PICU, we found that high-quality evidence to guide clinical practice is still limited. Pediatric randomized, controlled trials with reproducible methods and assessment of drug safety are needed.

Prolonged use of dexmedetomidine in the paediatric cardiothoracic intensive care unit

BACKGROUND

Dexmedetomidine is an alpha2-adrenergic agonist that causes sleep-like sedation and mild analgesia without narcosis or respiratory depression, and has relative cardiovascular stability. Due to these properties, it may be an effective agent for prolonged use in the sedation of patients in the paediatric cardiothoracic intensive care unit. We reviewed our experience with the drug to detail its safety and efficacy.

METHODS

We conducted a retrospective chart review of all patients who received dexmedetomidine over a six month period in a dedicated paediatric cardiothoracic intensive care unit. Patients were identified from pharmacy records showing administration of drugs. We collected demographic data, information relating to doses of dexmedetomidine, physiologic parameters, and clinical outcomes.

RESULTS

We identified 54 patients who received the drug. The median age of recipients was 6 months, with a range from 1 day to 16 years. The mean duration of administration was 37.3 hours, with a range from 2 to 177 hours. The mean duration of continuation of administration after extubation was 16.7 hours, with a range from zero to 112.5 hours. Physiologically, there were no clinically significant changes in mean arterial pressure, heart rate, respiratory rate, or saturations of oxygen before, during, or after utilization of the drug. Use of dexmedetomidine significantly reduced the need to administer narcotics, and scores using the COMFORT system were not different between patients who received dexmedetomidine and those who did not.

CONCLUSIONS

In this limited and retrospective review, dexmedetomidine was found to be safe and efficacious. Its use as a sedative agent for extended periods of time in critically-ill children deserves investigation in a prospective and controlled manner.