Withdrawal from multiple sedative agent therapy in an infant: is dexmedetomidine the cause or the cure?

Weaning Dexmedetomidine in Non-ICU Areas: An Implementation Effort

OBJECTIVES

To develop and implement clinical practice guidelines for safely weaning dexmedetomidine infusions in non-ICU areas.

DESIGN

Development, implementation, and analysis of effectiveness of clinical practice guidelines.

SETTING

Quaternary care academic free-standing pediatric hospital.

PATIENTS

Children, otherwise medically ready for transfer to non-ICU areas, who were undergoing a planned wean of a dexmedetomidine infusion.

INTERVENTIONS

Subject matter experts developed evidence-based guidelines for weaning dexmedetomidine in patients whose critical phase of illness had resolved.

MEASUREMENTS AND MAIN RESULTS

Searches identified no prospective studies of dexmedetomidine weaning. We identified two retrospective reviews of withdrawal symptoms and one on the use of clonidine. There were case studies on withdrawal symptoms. Guidelines were piloted on a cohort of 24 patients while in the ICU. The guidelines were then implemented in non-ICU areas for patients undergoing dexmedetomidine weaning after ICU transfer. Over a 2-year period (October 1, 2018, to September 30, 2020), 63 patients (1 mo to 18 yr old) successfully weaned dexmedetomidine in non-ICU areas. The median time to discontinuation of dexmedetomidine after transfer to non-ICU areas was 5.8 days (interquartile range, 4.75-15 d). Fifty-eight percent (n = 41) of all patients were considered high risk for dexmedetomidine withdrawal based on the dose, duration of exposure, and the risk of experiencing physiologic detriment with more than mild withdrawal. Twenty-nine patients (46%) exhibited no signs or symptoms of withdrawal while weaning per guidelines. For those with signs and symptoms of withdrawal, the most common were tachycardia (n = 26, 40%), agitation (n = 9, 14%), and hypertension (n = 9, 11%).

CONCLUSIONS

Weaning dexmedetomidine in non-ICU areas is feasible and can be accomplished safely even among pediatric patients at high risk for withdrawal using standardized weaning guidelines. At our institution, implementation was associated with reduced ICU length of stay for patients recovering from critical illness.

Clonidine as a strategy for discontinuing dexmedetomidine sedation in critically ill patients: A narrative review

PURPOSE

To review the efficacy and safety of transitioning from dexmedetomidine to clonidine to facilitate weaning of patients from sedation with dexmedetomidine. There is a paucity of data describing dexmedetomidine withdrawal syndrome (DWS) as well as clonidine's place in therapy for DWS. This review will describe and analyze current literature to provide clinical recommendations.

SUMMARY

A MEDLINE literature search was performed to identify original research articles describing DWS and/or transitioning from dexmedetomidine to clonidine for the purpose of weaning patients from sedation with dexmedetomidine. Four case reports describing DWS, 3 case reports describing the use of clonidine to treat DWS, and 3 observational studies describing the use of clonidine to facilitate dexmedetomidine weaning were identified. The incidence of and risk factors for DWS are unknown; factors including patient age and dexmedetomidine infusion rate, loading dose, and discontinuation strategy have inconsistent associations with DWS. All cases of DWS have been associated with infusion durations greater than 72 hours. While there are limited data describing clonidine use for the treatment of dexmedetomidine withdrawal, clonidine appears to be beneficial for dexmedetomidine weaning and its use for that purpose has been well described. Clonidine dosages that have been assessed for discontinuing dexmedetomidine vary from 0.1 to 0.3 mg orally or enterally every 6 to 8 hours; one study assessed use of transdermal clonidine (100 µg/24 h patch). Patients with extensive cardiac comorbidities may be more susceptible to adverse effects of clonidine, which may limit the drug's use for DWS intervention.

CONCLUSION

Despite limited supportive data, clonidine provides a promising option for sedation management in adult ICU patients, with successful transitions from dexmedetomidine reported within 24 hours after clonidine initiation.

Effects of a Clonidine Taper on Dexmedetomidine Use and Withdrawal in Adult Critically Ill Patients-A Pilot Study

OBJECTIVES

Prolonged use of dexmedetomidine has become increasingly common due to its favorable sedative and anxiolytic properties. Hypersympathetic withdrawal symptoms have been reported with abrupt discontinuation of prolonged dexmedetomidine infusions. Clonidine has been used to transition patients off dexmedetomidine infusions for ICU sedation. The objective of this study was to compare the occurrence of dexmedetomidine withdrawal symptoms in ICU patients transitioning to a clonidine taper versus those weaned off dexmedetomidine alone after prolonged dexmedetomidine infusion.

DESIGN

This was a single-center, prospective, double cohort observational study conducted from November 2017 to December 2018.

SETTING

Medical-surgical, cardiothoracic, and neurosurgical ICUs in a tertiary care hospital.

PATIENTS

We included adult ICU patients being weaned off dexmedetomidine after receiving continuous infusions for at least 3 days.

INTERVENTIONS

Patients were either weaned off dexmedetomidine alone or with a clonidine taper at the discretion of the providers.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was the incidence of at least two dexmedetomidine withdrawal symptoms during a single assessment within 24 hours of dexmedetomidine discontinuation. Time on dexmedetomidine after wean initiation and difference in medication cost were also evaluated. Forty-two patients were included in this study: 15 received clonidine (Group C) and 27 weaned off dexmedetomidine alone (Group D). There was no significant difference in the incidence of two or more withdrawal symptoms between groups (73% in Group C vs 59% in Group D; p = 0.51). Patients in Group C spent less time on dexmedetomidine after wean initiation compared with patients in Group D (19 vs 42 hr; p = 0.02). An average cost savings of $1,553.47 per patient who received clonidine was observed. No adverse effects were noted.

CONCLUSIONS

Our study demonstrated that patients receiving clonidine were able to wean off dexmedetomidine more rapidly, with a considerable cost savings and no difference in dexmedetomidine withdrawal symptoms, compared with patients weaned off dexmedetomidine alone. Clonidine may be a safe, effective, and practical option to transition patients off prolonged dexmedetomidine infusions.

Incidence of Rebound Hypertension after Discontinuation of Dexmedetomidine

INTRODUCTION

To date, no studies have evaluated the incidence of rebound hypertension occurring with the discontinuation of long-term (> 72 hrs) dexmedetomidine infusions. Rebound hypertension has been documented in the literature with clonidine, a structurally and pharmacologically similar medication.

OBJECTIVES

To compare the incidence of rebound hypertension associated with cessation of dexmedetomidine infusion with other sedative medications.

METHODS

This retrospective, matched cohort study evaluated the incidence of rebound hypertension in intensive care unit patients receiving continuous infusions of at least 72 hours in duration of dexmedetomidine, propofol, or midazolam.

RESULTS

The study population consisted of 216 patients: 54 treated with dexmedetomidine and 162 treated with propofol or midazolam. Rebound hypertension occurred significantly more often in patients with a history of hypertension (71.1%) than in patients with no prior hypertension (28.9%; p<0.001).There was no difference in incidence of rebound hypertension in the dexmedetomidine or propofol and midazolam arms (16.7% vs 17.9%, p=0.837). The titration timeframe for the dexmedetomidine infusion, defined as the time from peak infusion rate until discontinuation, was significantly shorter in patients with rebound hypertension (median duration, 4 hrs) compared with patients who did not have rebound hypertension (median duration, 17 hrs; p=0.011).

CONCLUSION

There was no difference in the incidence of rebound hypertension observed with dexmedetomidine discontinuation compared with propofol or midazolam. Instead, history of hypertension and a shorter weaning duration appear to be associated with increased risk of rebound hypertension regardless of the sedative used.

Incidence of Dexmedetomidine Withdrawal in Adult Critically Ill Patients: A Pilot Study

To determine the incidence of dexmedetomidine withdrawal in adult critically ill patients.

DESIGN

This was a prospective, observational study of patients from November 2017 to December 2018.

SETTING

Medical-surgical, cardiothoracic, and neurosurgical ICUs in a tertiary care hospital.

PATIENTS

Adult critically ill patients on dexmedetomidine infusions for at least 3 days.

INTERVENTIONS

Indicators of withdrawal were assessed at baseline and at least daily during the dexmedetomidine wean period. Delirium was assessed using the Confusion Assessment Method for the ICU. Sedation was assessed using the Richmond Agitation-Sedation Scale. The Withdrawal Assessment Tool-1 was performed and vital signs were recorded during each assessment. Patients were considered positive for dexmedetomidine withdrawal if they had two or more of the following symptoms: positive Confusion Assessment Method for the ICU, Richmond Agitation-Sedation Scale greater than +1, positive Withdrawal Assessment Tool-1 assessment, tachycardia (heart rate > 90 beats/min), and hypertension (systolic blood pressure > 140 mm Hg or mean arterial pressure > 90).

MEASUREMENTS AND MAIN RESULTS

Forty-two patients were included in the study, with 64% of patients experiencing signs of dexmedetomidine withdrawal. The median time on dexmedetomidine for all patients was 9.6 days (5.8-12.7 d), and the median dose of dexmedetomidine received was 0.8 µg/kg/hr (0.5-1 µg/kg/hr). Of the patients who were positive for withdrawal, the most prevalent withdrawal symptoms observed included delirium, hypertension, and agitation (93%, 48%, and 33%, respectively). We found no correlation between chronic opioid tolerance and incidence of withdrawal symptoms. Peak dexmedetomidine doses greater than 0.8 µg/kg/hr and cumulative daily doses of dexmedetomidine greater than 12.9 µg/kg/d were associated with a higher incidence of withdrawal.

CONCLUSIONS

The majority of patients in our study demonstrated signs that may be indicative of dexmedetomidine withdrawal. Peak and cumulative daily dexmedetomidine dose, rather than duration of therapy, may be associated with a higher incidence of withdrawal signs. Regular screening of patients on prolonged dexmedetomidine infusions is recommended to ensure safe and effective use in critically ill patients.

Interprofessional Team's Perception of Care Delivery After Implementation of a Pediatric Pain and Sedation Protocol

BACKGROUND

Pain and agitation are common experiences of patients in pediatric cardiac intensive care units. Variability in assessments by health care providers, communication, and treatment of pain and agitation creates challenges in management of pain and sedation.

OBJECTIVES

To develop guidelines for assessment and treatment of pain, agitation, and delirium in the pediatric cardiac intensive unit in an academic children's hospital and to document the effects of implementation of the guidelines on the interprofessional team's perception of care delivery and team function.

METHODS

Before and after implementation of the guidelines, interprofessional team members were surveyed about the members' perception of analgesia, sedation, and delirium management RESULTS: Members of the interprofessional team felt more comfortable with pain and sedation management after implementation of the guidelines. Team members reported improvements in team communication on patients' comfort. Members thought that important information was less likely to be lost during transfer of care. They also noted that the team carried out comfort management plans and used pharmacological and nonpharmacological therapies better after implementation of the guidelines than they did before implementation.

CONCLUSIONS

Guidelines for pain and sedation management were associated with perceived improvements in team function and patient care by members of the interprofessional team.

Prolonged Dexmedetomidine Infusion and Drug Withdrawal In Critically Ill Children

OBJECTIVE

To characterise the incidence, symptoms and risk factors for withdrawal associated with prolonged dexmedetomidine infusion in paediatric critically ill patients.

METHODS

Retrospective chart review in the paediatric intensive care unit and the cardiac critical care unit of a single tertiary children's hospital. Patients up to 18 years old, who received dexmedetomidine for longer than 48 hours were included.

RESULTS

A total of 52 patients accounted for 68 unique dexmedetomidine treatment courses of more than 48 hours. We identified 24 separate episodes of withdrawal in the 68 dexmedetomidine courses (incidence 35%). Of these episodes 38% occurred in patients who were weaned from dexmedetomidine alone while the remaining occurred in patients who had concurrent weans of opioids and/or benzodiazepines. Most common symptoms were agitation, fever, vomiting/retching, loose stools and decreased sleep. The symptoms occurred during the latter part of the wean or after discontinuation of dexmedetomidine. A cumulative dose of dexmedetomidine of 107 mcg/kg prior to initiation of wean was more likely associated with withdrawal (this equates to a dexmedetomidine infusion running at 1 mcg/kg/hr over 4 days). Duration of opioid use was an additional risk factor for withdrawal. The use of clonidine, as a transition from dexmedetomidine, did not protect against withdrawal (p = 1).

CONCLUSIONS

A withdrawal syndrome may occur after prolonged infusion of dexmedetomidine. As all our patients were also exposed to opioids this may be affected by the duration of opioid use. We identified a cumulative dose of 107 micrograms/kg of dexmedetomidine beyond which withdrawal symptoms were more likely (which equates to 4 days of use at a dose of 1 mcg/kg/hr). A protocol for weaning should be considered in this circumstance.

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.

Optimizing Sedation Management to Promote Early Mobilization for Critically Ill Children

Achieving successful early mobilization for the intubated, critically ill child is dependent on optimizing sedation and analgesia. Finding the fine balance between oversedation and undersedation can be challenging. The ideal is for a child to be lucid and interactive during the daytime and demonstrate normal circadian rhythm for sleep with rest at night. Being alert during the day facilitates active participation in therapy including potential ambulation, while decreasing the risk of delirium during mechanical ventilation. An active state during the day with frequent mobilization promotes restorative sleep at night, which brings with it multiple benefits for healing and recovery. Indeed, this ideal may not be physiologically feasible given a child's critical illness and trajectory, but defining it as the "gold standard" for early mobilization provides a consistent goal for the pediatric intensive care unit (PICU) hospitalization. As such, goal-directed, patient-specific sedation plans are integral to creating a culture of mobility in the PICU. We review currently available sedation strategies for mechanically ventilated children for successful implementation of early mobilization in the PICU, as well as pharmacologic considerations for specific classes of sedative-analgesics.

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.

Sedation, sleep promotion, and delirium screening practices in the care of mechanically ventilated children: a wake-up call for the pediatric critical care community*

OBJECTIVES

To examine pediatric intensivist sedation management, sleep promotion, and delirium screening practices for intubated and mechanically ventilated children.

DESIGN

An international, online survey of questions regarding sedative and analgesic medication choices and availability, sedation protocols, sleep optimization, and delirium recognition and treatment.

SETTING

Member societies of the World Federation of Pediatric Intensive and Critical Care Societies were asked to send the survey to their mailing lists; responses were collected from July 2012 to January 2013.

SUBJECTS

Pediatric critical care providers.

INTERVENTIONS

Survey.

MEASUREMENTS AND MAIN RESULTS

The survey was completed by 341 respondents, the majority of whom were from North America (70%). Twenty-seven percent of respondents reported having written sedation protocols. Most respondents worked in PICUs with sedation scoring systems (70%), although only 42% of those with access to scoring systems reported routine daily use for goal-directed sedation management. The State Behavioral Scale was the most commonly used scoring system in North America (22%), with the COMFORT score more prevalent in all other countries (39%). The most commonly used sedation regimen for intubated children was a combination of opioid and benzodiazepine (72%). Most intensivists chose fentanyl as their first-line opioid (66%) and midazolam as their first-line benzodiazepine (86%) and prefer to administer these medications as continuous infusions. Propofol and dexmedetomidine were the most commonly restricted medications in PICUs internationally. Use of earplugs, eye masks, noise reduction, and lighting optimization for sleep promotion was uncommon. Delirium screening was not practiced in 71% of respondent's PICUs, and only 2% reported routine screening at least twice a day.

CONCLUSIONS

The results highlight the heterogeneity in sedation practices among intensivists who care for critically ill children as well as a paucity of sleep promotion and delirium screening in PICUs worldwide.

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.

Two cases of acute dexmedetomidine withdrawal syndrome following prolonged infusion in the intensive care unit: Report of cases and review of the literature

Prolonged infusion of dexmedetomidine, an α(2)-adrenoreceptor agonist anesthetic used in the intensive care unit, produces a withdrawal syndrome of sympathetic over-activity, characterized by tachycardia, hypertension and agitation, but there is no recommended standard treatment for this syndrome. We describe two patients with a clinical diagnosis of acute dexmedetomidine withdrawal and its management with oral clonidine. We utilized the principle of managing acute drug withdrawal with longer acting medications. These two cases demonstrated the benefit of using oral, longer acting clonidine to manage acute withdrawal from shorter-acting, intravenous dexmedetomidine.

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.

Perceived versus actual sedation practices in adult intensive care unit patients receiving mechanical ventilation

BACKGROUND

With drug shortages, newer sedative medications, and updates in research, management of sedation and delirium in patients receiving mechanical ventilation continues to evolve.

OBJECTIVE

To compare perceived and actual sedation practices for adults receiving mechanical ventilation in intensive care units (ICUs).

METHODS

This was a multicenter, 2-part study conducted in adult ICUs in US hospitals. It included a sedation practice survey completed by ICU pharmacists and an observational study evaluating actual sedation practices over a 24-hour period.

RESULTS

Surveys were completed for 85 ICUs; observational data for 496 patients were collected. Preferred sedatives from the survey data were propofol (short-term); propofol, midazolam, or lorazepam (intermediate); and lorazepam (long-term). Propofol was the most commonly used agent overall during the observational period (primarily for short-term and intermediate-length sedation); midazolam was the most commonly used for long-term sedation. Fentanyl was the preferred analgesic, and haloperidol and quetiapine were the preferred antipsychotics. Sedation treatment algorithms were used in only 50% of observed ICUs. Use of daily interruption of sedation was perceived to be 66% but was only observed in 36% of patients. Monitoring for delirium was reported among 25% of those surveyed but was observed in only 10% of patients. Targeted sedation goals were most frequently achieved when a treatment algorithm was used or when an opiate infusion was the single agent used for sedative management.

CONCLUSIONS

These data suggest differences in perceived and actual sedation practice in the US, as well as underutilization of evidence-based interventions. Most notable was the limited use of sedation treatment algorithms, daily interruption of sedation, and monitoring for delirium. Individual sedation and delirium protocols should be evaluated and updated based on evidence-based recommendations.

Discontinuation of prolonged infusions of dexmedetomidine in critically ill children with heart disease

PURPOSE

To describe changes in hemodynamic variables, sedation, and pain score after discontinuation of prolonged infusions of dexmedetomidine in a pediatric population of critically ill cardiac patients.

METHODS

Retrospective case series of patients who received continuous infusions of dexmedetomidine for longer than 3 days in a pediatric cardiac intensive care unit from 2008 to 2010.

RESULTS

Sixty-two patients, age 5.2 months (range 0.3 months-17 years) and weight 5.1 kg (range 2.2-84 kg), were included. Thirty-nine patients (63%) were younger than 1 year of age. Median duration of dexmedetomidine infusion was 5.8 days (range 4-26 days) and median infusion dose was 0.71 μg/kg/h (range 0.2-2.1 μg/kg/h). Median weaning time and dose at discontinuation were 43 h (range 0-189 h) and 0.2 μg/kg/h (range 0.1-1.3 μg/kg/h). Tachycardia, transient hypertension and agitation were observed in 27, 35 and 27% of patients. Episodes of tachycardia were more frequent in children older than 1 year of age (61 vs. 8%, p < 0.001), patients who received dexmedetomidine for 4 days when compared to those who received 5 days or longer (48 vs. 17%, p = 0.011), and patients whose infusion was discontinued abruptly (42 vs. 14%, p = 0.045). Tachyarrhythmias were seen in nine patients (15%) after discontinuation of the dexmedetomidine infusion. Adequate sedation and analgesia scores at the moment of infusion discontinuation were seen in 90 and 88% of patients, respectively.

CONCLUSIONS

Our study suggests that tachycardia, transient hypertension, and agitation are frequently observed in pediatric cardiac intensive care unit patients after discontinuing prolonged dexmedetomidine infusions.

Tolerance and addiction; the patient, the parent or the clinician?

Tolerance has been recognized for some time where chronic exposure to certain drugs, particularly benzodiazepines and opioids, is associated with apparent tachyphylaxis. When these drugs are stopped or progressively reduced as in 'tapering', withdrawal symptoms may result. Tolerance and the flip side of the coin, withdrawal, are the determinants of addiction. It is increasingly apparent that tolerance can occur acutely, even within the time span of a single anesthetic for a surgical procedure. Addiction is caused by agents, foreign to the body, that provoke adaptation by homeostatic biological processes. When these agents are withdrawn, the adaptive mechanisms, devoid of substrate, take time to diminish and produce symptoms recognizable under the term of 'withdrawal'. Children may be exposed to these agents in different ways; in utero, as a result of substances that the mother ingests by enteral, parenteral or inhalational means that are transmitted to the infant via the placenta; as a result of an anesthetic for surgery; or as a result of sedation and analgesia administered to offset the stresses and trauma inherent from intensive care treatment in the neonatal intensive care unit or pediatric intensive care unit. Additionally, anesthetic and intensive care staff are exposed to powerful and addictive drugs as part of everyday practice, not simply by overt access, but also by subliminal environmental exposure.