A prospective study of the adverse effects of midazolam on withdrawal in critically ill children

Sedation level with midazolam: a pediatric surgery approach

Midazolam (MDZ) is a short-acting benzodiazepine that is widely used to induce and maintain general anesthesia during diagnostic and therapeutic procedures in pediatric patients due to its sedative properties. The aim of this study was to perform a systematic review without a meta-analysis to identify scientific articles and clinical assays concerning MDZ-induced sedation for a pediatric surgery approach. One hundred and twenty-eight results were obtained. After critical reading, 37 articles were eliminated, yielding 91 publications. Additional items were identified, and the final review was performed with a total of 106 publications.

In conclusion, to use MDZ accurately, individual patient characteristics, the base disease state, comorbidities, the treatment burden and other drugs with possible pharmacological interactions or adverse reactions must be considered to avoid direct alterations in the pharmacokinetics and pharmacodynamics of MDZ to obtain the desired effects and avoid overdosing in the pediatric population.

2022 Society of Critical Care Medicine Clinical Practice Guidelines on Prevention and Management of Pain, Agitation, Neuromuscular Blockade, and Delirium in Critically Ill Pediatric Patients With Consideration of the ICU Environment and Early Mobility

RATIONALE

A guideline that both evaluates current practice and provides recommendations to address sedation, pain, and delirium management with regard for neuromuscular blockade and withdrawal is not currently available.

OBJECTIVE

To develop comprehensive clinical practice guidelines for critically ill infants and children, with specific attention to seven domains of care including pain, sedation/agitation, iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment, and early mobility.

DESIGN

The Society of Critical Care Medicine Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility Guideline Taskforce was comprised of 29 national experts who collaborated from 2009 to 2021 via teleconference and/or e-mail at least monthly for planning, literature review, and guideline development, revision, and approval. The full taskforce gathered annually in-person during the Society of Critical Care Medicine Congress for progress reports and further strategizing with the final face-to-face meeting occurring in February 2020. Throughout this process, the Society of Critical Care Medicine standard operating procedures Manual for Guidelines development was adhered to.

METHODS

Taskforce content experts separated into subgroups addressing pain/analgesia, sedation, tolerance/iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment (family presence and sleep hygiene), and early mobility. Subgroups created descriptive and actionable Population, Intervention, Comparison, and Outcome questions. An experienced medical information specialist developed search strategies to identify relevant literature between January 1990 and January 2020. Subgroups reviewed literature, determined quality of evidence, and formulated recommendations classified as "strong" with "we recommend" or "conditional" with "we suggest." Good practice statements were used when indirect evidence supported benefit with no or minimal risk. Evidence gaps were noted. Initial recommendations were reviewed by each subgroup and revised as deemed necessary prior to being disseminated for voting by the full taskforce. Individuals who had an overt or potential conflict of interest abstained from relevant votes. Expert opinion alone was not used in substitution for a lack of evidence.

RESULTS

The Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility taskforce issued 44 recommendations (14 strong and 30 conditional) and five good practice statements.

CONCLUSIONS

The current guidelines represent a comprehensive list of practical clinical recommendations for the assessment, prevention, and management of key aspects for the comprehensive critical care of infants and children. Main areas of focus included 1) need for the routine monitoring of pain, agitation, withdrawal, and delirium using validated tools, 2) enhanced use of protocolized sedation and analgesia, and 3) recognition of the importance of nonpharmacologic interventions for enhancing patient comfort and comprehensive care provision.

Treatment of benzodiazepine withdrawal syndrome in a severe traumatic brain injury patient

Prolonged exposure to benzodiazepines (BDZ) may contribute towards physical dependence, which is manifested by iatrogenic Benzodiazepine Withdrawal Syndrome (BWS), a condition often underdiagnosed. Current evidence recommends precluding BDZ infusion as sedation in the intensive care unit to avoid possible withdrawal and delirium issues. Administration of dexmedetomidine should be considered to facilitate weaning in patients with BWS.

Differences in efficacy and safety of midazolam vs. dexmedetomidine in critically ill patients: A meta-analysis of randomized controlled trial

The present study aimed to compare the efficacy and safety of dexmedetomidine and midazolam in patients that are critically ill. Full text articles reporting the clinical effects and complications of dexmedetomidine and midazolam were retrieved from multiple databases. Review Manager 5.0 was adopted for meta-analysis, sensitivity and bias analysis. Finally, a total of 1,379 patients from 8 studies, which met the eligibility criteria, were included. The meta-analysis suggested that the length of stay at the intensive care unit [mean absolute difference (MD)=-1.80; 95% confidence interval (CI), -2.13, -1.48; P<0.00001; P-value for heterogeneity=0.41; I²=3%], time to extubation (MD=-2.18; 95% CI, -2.66, -1.69; P<0.00001; P-value for heterogeneity=0.84; I²=0%) and delirium (MD=0.46; 95% CI, 0.37, 0.57; P<0.00001; P-value for heterogeneity=0.65; I²=0%) was higher following midazolam treatment compared with dexmedetomidine, while bradycardia [odds ratio (OR)=5.03; 95% CI, 3.86, 6.57; P<0.00001; P-value for heterogeneity=0.13; I²=38%] was higher in dexmedetomidine treated patients compared with midazolam. However, no difference was observed in the incidence of hypotension (OR=0.88; 95% CI, 0.70, 1.10; P=0.26; P-value for heterogeneity=0.99; I²=0%) and mortality (OR=0.96; 95% CI, 0.74, 1.25; P=0.77; P-value for heterogeneity=0.99; I²=0%). Taking clinical effects and safety into account, the present study suggested dexmedetomidine to be the preferred option of anesthesia for patients that are critically ill.

Oral lorazepam can be substituted for intravenous midazolam when weaning paediatric intensive care patients off sedation

AIM

Intravenous sedatives used in the paediatric intensive care unit (PICU) need to be tapered after prolonged use to prevent iatrogenic withdrawal syndrome (IWS). We evaluated the occurrence of IWS and the levels of sedation before and after conversion from intravenous midazolam to oral lorazepam.

METHODS

This was a retrospective, observational, single cohort study of children under the age of 18 admitted to the PICU of the Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands, between January 2013 and December 2014. The outcome parameters were the Sophia Observation withdrawal Symptoms (SOS) scale scores and COMFORT Behaviour scale scores before and after conversion.

RESULTS

Of the 79 patients who were weaned, 32 and 39 had before and after SOS scores and 77 had COMFORT-B scores. IWS was reported in 15 of 79 patients (19.0%) during the 48 hours before the start of lorazepam and 17 of 79 patients (21.5%) during the 48 hours after treatment started. Oversedation was seen in 16 of 79 patients (20.3%) during the 24 hours before substitution and in 30 of 79 patients (38.0%) during the 24 hours after substitution.

CONCLUSION

The weaning protocol was not able to prevent IWS in all patients, but converting from intravenous midazolam to oral lorazepam did not increase the incidence.

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.

Opioid-associated iatrogenic withdrawal in critically ill adult patients: a multicenter prospective observational study

Background

Opioids and benzodiazepines are frequently used in the intensive care unit (ICU). Regular use and prolonged exposure to opioids in ICU patients followed by abrupt tapering or cessation may lead to iatrogenic withdrawal syndrome (IWS). IWS is well described in pediatrics, but no prospective study has evaluated this syndrome in adult ICU patients. The objective of this study was to determine the incidence of IWS caused by opioids in a critically ill adult population. This multicenter prospective cohort study was conducted at two level-1 trauma ICUs between February 2015 and September 2015 and included 54 critically ill patients. Participants were eligible if they were 18 years and older, mechanically ventilated and had received more than 72 h of regular intermittent or continuous intravenous infusion of opioids. For each enrolled patient and per each opioid weaning episode, presence of IWS was assessed by a qualified ICU physician or senior resident according to the 5th edition of Diagnostic and Statistical Manual of Mental Disorders criteria for opioid withdrawal.

Results

The population consisted mostly of males (74.1%) with a median age of 50 years (25th–75th percentile 38.2–64.5). The median ICU admission APACHE II score was 22 (25th–75th percentile 12.0–28.2). The overall incidence of IWS was 16.7% (95% CI 6–27). The median cumulative opioid dose prior to weaning was higher in patients with IWS (245.7 vs. 169.4 mcg/kg, fentanyl equivalent). Patients with IWS were also exposed to opioids for a longer period of time as compared to patients without IWS (median 151 vs. 125 h). However, these results were not statistically significant.

Conclusions

IWS was occasionally observed in this very specific population of mechanically ventilated, critically ill ICU patients. Further studies are needed to confirm these preliminary results and identify risk factors.

Differentiating Delirium From Sedative/Hypnotic-Related Iatrogenic Withdrawal Syndrome: Lack of Specificity in Pediatric Critical Care Assessment Tools

OBJECTIVES

To identify available assessment tools for sedative/hypnotic iatrogenic withdrawal syndrome and delirium in PICU patients, the evidence supporting their use, and describe areas of overlap between the components of these tools and the symptoms of anticholinergic burden in children.

DATA SOURCES

Studies were identified using PubMed and EMBASE from the earliest available date until July 3, 2016, using a combination of MeSH terms "delirium," "substance withdrawal syndrome," and key words "opioids," "benzodiazepines," "critical illness," "ICU," and "intensive care." Review article references were also searched.

STUDY SELECTION

Human studies reporting assessment of delirium or iatrogenic withdrawal syndrome in children 0-18 years undergoing critical care. Non-English language, exclusively adult, and neonatal intensive care studies were excluded.

DATA EXTRACTION

References cataloged by study type, population, and screening process.

DATA SYNTHESIS

Iatrogenic withdrawal syndrome and delirium are both prevalent in the PICU population. Commonly used scales for delirium and iatrogenic withdrawal syndrome assess signs and symptoms in the motor, behavior, and state domains, and exhibit considerable overlap. In addition, signs and symptoms of an anticholinergic toxidrome (a risk associated with some common PICU medications) overlap with components of these scales, specifically in motor, cardiovascular, and psychiatric domains.

CONCLUSIONS

Although important studies have demonstrated apparent high prevalence of iatrogenic withdrawal syndrome and delirium in the PICU population, the overlap in these scoring systems presents potential difficulty in distinguishing syndromes, both clinically and for research purposes.

Impact of a Standardized Treatment Guideline for Pediatric Iatrogenic Opioid Dependence: A Quality Improvement Initiative

OBJECTIVES

To determine whether utilization of a hospital-based clinical practice guideline for the care of pediatric iatrogenic opioid dependence (IOD) would promote a decrease in opioid exposure and improve management of opioid abstinence syndrome (AS).

METHODS

This study is a retrospective chart review of critically ill patients from a tertiary care children's hospital. Inclusion criteria included mechanically ventilated patients up to 18 years of age who received continuous opioid infusions for at least 7 days and any length of methadone administration. Data on IOD patients from January 2005 to June 2010 was divided into 3 periods: baseline, phase 1, and phase 2. Primary outcome was decrease in opioid exposure, measured by methadone duration of use and any additional opioid bolus doses used in AS management. Documentation of additional opioid bolus doses was regarded as a surrogate measure of AS. Secondary outcomes included total cumulative fentanyl dose, continuous fentanyl infusion duration of use, and hospital and pediatric intensive care unit length of stay.

RESULTS

There was a significant decrease in methadone duration of use in IOD patients from 15.3 ± 8.7 days at baseline to 9.5 ± 3.7 days during phase 1 (p = 0.002), to 8.1 ± 3.7 days on phase 2 (reduction not significant, p = 0.106) of this evaluation. Additional opioid bolus doses were significantly lower from baseline to phase 1 (5.5 ± 5.1 vs. 1.8 ± 2.3, p = 0.001) and from phase 1 to phase 2 (1.8 ± 2.3 vs. 0.2 ± 1.5, p = 0.003). For the remaining outcomes, differences were not observed among the evaluation periods, except for the total cumulative fentanyl dose, which was reduced from 2.8 ± 3.7 mg/kg at baseline to 1 ± 1 mg/kg only during phase 1 (p = 0.017).

CONCLUSIONS

Introduction of a standardized, hospital-based clinical practice guideline for children with IOD reduced the length of exposure to opioids and improved opioid AS management.

Prospective multicentre randomised, double-blind, equivalence study comparing clonidine and midazolam as intravenous sedative agents in critically ill children: the SLEEPS (Safety profiLe, Efficacy and Equivalence in Paediatric intensive care Sedation) study

BACKGROUND

Children in paediatric intensive care units (PICUs) require analgesia and sedation but both undersedation and oversedation can be harmful.

OBJECTIVE

Evaluation of intravenous (i.v.) clonidine as an alternative to i.v. midazolam.

DESIGN

Multicentre, double-blind, randomised equivalence trial.

SETTING

Ten UK PICUs.

PARTICIPANTS

Children (30 days to 15 years inclusive) weighing ≤ 50 kg, expected to require ventilation on PICU for > 12 hours.

INTERVENTIONS

Clonidine (3 µg/kg loading then 0-3 µg/kg/hour) versus midazolam (200 µg/kg loading then 0-200 µg/kg/hour). Maintenance infusion rates adjusted according to behavioural assessment (COMFORT score). Both groups also received morphine.

MAIN OUTCOME MEASURES

Primary end point Adequate sedation defined by COMFORT score of 17-26 for ≥ 80% of the time with a ± 0.15 margin of equivalence. Secondary end points Percentage of time spent adequately sedated, increase in sedation/analgesia, recovery after sedation, side effects and safety data.

RESULTS

The study planned to recruit 1000 children. In total, 129 children were randomised, of whom 120 (93%) contributed data for the primary outcome. The proportion of children who were adequately sedated for ≥ 80% of the time was 21 of 61 (34.4%) - clonidine, and 18 of 59 (30.5%) - midazolam. The difference in proportions for clonidine-midazolam was 0.04 [95% confidence interval (CI) -0.13 to 0.21], and, with the 95% CI including values outside the range of equivalence (-0.15 to 0.15), equivalence was not demonstrated; however, the study was underpowered. Non-inferiority of clonidine to midazolam was established, with the only values outside the equivalence range favouring clonidine. Times to reach maximum sedation and analgesia were comparable hazard ratios: 0.99 (95% CI 0.53 to 1.82) and 1.18 (95% CI 0.49 to 2.86), respectively. Percentage time spent adequately sedated was similar [medians clonidine 73.8% vs. midazolam 72.8%: difference in medians 0.66 (95% CI -5.25 to 7.24)]. Treatment failure was 12 of 64 (18.8%) on clonidine and 7 of 61 (11.5%) on midazolam [risk ratio (RR) 1.63, 95% CI 0.69 to 3.88]. Proportions with withdrawal symptoms [28/60 (46.7%) vs. 30/58 (52.6%)] were similar (RR 0.89, 95% CI 0.62 to 1.28), but a greater proportion required clinical intervention in those receiving midazolam [11/60 (18.3%) vs. 16/58 (27.6%) (RR 0.66, 95% CI 0.34 to 1.31)]. Post treatment, one child on clonidine experienced mild rebound hypertension, not requiring intervention. A higher incidence of inotropic support during the first 12 hours was required for those on clonidine [clonidine 5/45 (11.1%) vs. midazolam 3/52 (5.8%)] (RR 1.93 95% CI 0.49 to 7.61).

CONCLUSIONS

Clonidine is an alternative to midazolam. Our trial-based economic evaluation suggests that clonidine is likely to be a cost-effective sedative agent in the PICU in comparison with midazolam (probability of cost-effectiveness exceeds 50%). Rebound hypertension did not appear to be a significant problem with clonidine but, owing to its effects on heart rate, specific cardiovascular attention needs to be taken during the loading and early infusion phase. Neither drug in combination with morphine provided ideal sedation, suggesting that in unparalysed patients a third background agent is necessary. The disappointing recruitment rates reflect a reluctance of parents to provide consent when established on a sedation regimen, and reluctance of clinicians to allow sedation to be studied in unstable critically ill children. Future studies will require less exacting protocols allowing enhanced recruitment.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN02639863.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 71. See the NIHR Journals Library website for further project information.

Ketamine for continuous sedation of mechanically ventilated patients

CONTEXT

Long-term sedation with midazolam or propofol has been demonstrated to have serious adverse side effects, such as toxic accumulation or propofol infusion syndrome. Ketamine remains a viable alternative for continuous sedation as it is inexpensive and widely available, however, there are few analyses regarding its safety in this clinical setting.

OBJECTIVE

To review the data related to safety and efficacy of ketamine as a potential sedative agent in mechanically ventilated patients admitted to the intensive care unit (ICU).

MATERIALS AND METHODS

This was a single-center retrospective study from September 2011 to March 2012 of patients who required sedation for greater than 24 hours, in whom ketamine was selected as the primary sedative agent. All patients greater than 18 years of age, regardless of admitting diagnosis, were eligible for inclusion. Patients that received ketamine for continuous infusion but died prior to receiving it for 24 hours were not included.

RESULTS

Thirty patients received ketamine for continuous sedation. In four patients, ketamine was switched to another sedative agent due to possible adverse side effects. Of these, two patients had tachydysrhythmias, both with new onset atrial fibrillation and two patients had agitation believed to be caused by ketamine. The adverse event rate in our patient population was 13% (4/30).

CONCLUSIONS

Among ICU patients receiving prolonged mechanical ventilation, the use of ketamine appeared to have a frequency of adverse events similar to more common sedative agents, like propofol and benzodiazepines.

Ketamine for continuous sedation of mechanically ventilated patients

Context:

Long-term sedation with midazolam or propofol has been demonstrated to have serious adverse side effects, such as toxic accumulation or propofol infusion syndrome. Ketamine remains a viable alternative for continuous sedation as it is inexpensive and widely available, however, there are few analyses regarding its safety in this clinical setting.

Objective:

To review the data related to safety and efficacy of ketamine as a potential sedative agent in mechanically ventilated patients admitted to the intensive care unit (ICU).

Materials and Methods:

This was a single-center retrospective study from September 2011 to March 2012 of patients who required sedation for greater than 24 hours, in whom ketamine was selected as the primary sedative agent. All patients greater than 18 years of age, regardless of admitting diagnosis, were eligible for inclusion. Patients that received ketamine for continuous infusion but died prior to receiving it for 24 hours were not included.

Results:

Thirty patients received ketamine for continuous sedation. In four patients, ketamine was switched to another sedative agent due to possible adverse side effects. Of these, two patients had tachydysrhythmias, both with new onset atrial fibrillation and two patients had agitation believed to be caused by ketamine. The adverse event rate in our patient population was 13% (4/30).

Conclusions:

Among ICU patients receiving prolonged mechanical ventilation, the use of ketamine appeared to have a frequency of adverse events similar to more common sedative agents, like propofol and benzodiazepines.

Risk factors associated with iatrogenic opioid and benzodiazepine withdrawal in critically ill pediatric patients: a systematic review and conceptual model

OBJECTIVES

Analgesia and sedation are common therapies in pediatric critical care, and rapid titration of these medications is associated with iatrogenic withdrawal syndrome. We performed a systematic review of the literature to identify all common and salient risk factors associated with iatrogenic withdrawal syndrome and build a conceptual model of iatrogenic withdrawal syndrome risk in critically ill pediatric patients.

DATA SOURCES

Multiple databases, including PubMed/Medline, EMBASE, CINAHL, and the Cochrane Central Registry of Clinical Trials, were searched using relevant terms from January 1, 1980, to August 1, 2014.

STUDY SELECTION

Articles were included if they were published in English and discussed iatrogenic withdrawal syndrome following either opioid or benzodiazepine therapy in children in acute or intensive care settings. Articles were excluded if subjects were neonates born to opioid- or benzodiazepine-dependent mothers, children diagnosed as substance abusers, or subjects with cancer-related pain; if data about opioid or benzodiazepine treatment were not specified; or if primary data were not reported.

DATA EXTRACTION

In total, 1,395 articles were evaluated, 33 of which met the inclusion criteria. To facilitate analysis, all opioid and/or benzodiazepine doses were converted to morphine or midazolam equivalents, respectively. A table of evidence was developed for qualitative analysis of common themes, providing a framework for the construction of a conceptual model. The strongest risk factors associated with iatrogenic withdrawal syndrome include duration of therapy and cumulative dose. Additionally, evidence exists linking patient, process, and system factors in the development of iatrogenic withdrawal syndrome.

FINDINGS

Most articles were prospective observational or interventional studies.

CONCLUSIONS

Given the state of existing evidence, well-designed prospective studies are required to better characterize iatrogenic withdrawal syndrome in critically ill pediatric patients. This review provides data to support the construction of a conceptual model of iatrogenic withdrawal syndrome risk that, if supported, could be useful in guiding future research.

High doses of benzodiazepine predict analgesic and sedative drug withdrawal syndrome in paediatric intensive care patients

AIM

Critically ill children can develop withdrawal syndrome after prolonged analgesia and sedation in a paediatric intensive care unit (PICU), when treatment is stopped abruptly or reduced quickly. The aim of this study was to evaluate the incidence of withdrawal syndrome in patients after three or more days of analgesic or sedative drug therapy, using a validated scale. We also analysed the association between withdrawal syndrome and the patients' outcome and factors related to analgesia and sedation treatment.

METHODS

This prospective observational study analysed 89 periods of weaning from analgesia and sedation in 60 children between October 2010 and October 2011. Of these, 65% were less than six months old and 45% were admitted to the PICU after heart surgery. Withdrawal syndrome was assessed using the Withdrawal Assessment Tool-1 (WAT-1) scale.

RESULTS

The incidence of withdrawal syndrome was 37%, and the only variable that predicted its presence was the highest administered dose of benzodiazepine. The duration of weaning, Sophia Observational Withdrawal Symptom scale score and nurse judgment were also associated with positive WAT-1 scores.

CONCLUSION

Withdrawal syndrome should be considered after three or more days of analgesic or sedative treatment. A high dose of benzodiazepine increases the risk of developing withdrawal symptoms.

Clonidine in the sedation of mechanically ventilated children: a pilot randomized trial

PURPOSE

Clonidine is often used as a sedative in critically ill children, but its effectiveness has not been evaluated in a large, rigorous randomized controlled trial. Our objectives in this pilot trial were to assess the feasibility of a larger trial with respect to (1) effective screening, (2) recruitment, (3) timely drug administration, and (4) protocol adherence.

MATERIALS AND METHODS

This is a randomized, blinded, placebo-controlled pilot trial. Mechanically ventilated children received enteral clonidine 5 μg/kg or placebo every 6 hours; additional sedatives were at the discretion of attending physicians.

RESULTS

We enrolled 50 children. The median interquartile range (IQR) age was 2.5 (0.7-5.2) years, and Pediatric Risk of Mortality score on pediatric intensive care unit admission was 12 (8-15). In terms of feasibility outcomes, 90 (87%) of 104 eligible patients were approached for consent, and on average, 1.7 children were enrolled per month. Thirty-five (70%) were enrolled within 1 day of becoming eligible (mean, 1.2 days). Thereafter, 94% of doses were administered by protocol. Clinical outcomes and adverse effects were not significantly different between the groups.

CONCLUSIONS

This pilot trial demonstrated feasibility of a larger randomized controlled trial. Some important challenges emerged, allowing refinement of the study protocol and enrolment estimates. We recommend that future trials capitalize on the experience gained and use these results to design a larger trial focusing on clinically important outcomes.

Clinical pharmacology of midazolam in neonates and children: effect of disease-a review

Midazolam is a benzodiazepine with rapid onset of action and short duration of effect. In healthy neonates the half-life (t_1/2) and the clearance (Cl) are 3.3-fold longer and 3.7-fold smaller, respectively, than in adults. The volume of distribution (Vd) is 1.1 L/kg both in neonates and adults. Midazolam is hydroxylated by CYP3A4 and CYP3A5; the activities of these enzymes surge in the liver in the first weeks of life and thus the metabolic rate of midazolam is lower in neonates than in adults. Midazolam acts as a sedative, as an antiepileptic, for those infants who are refractory to standard antiepileptic therapy, and as an anaesthetic. Information of midazolam as an anaesthetic in infants are very little. Midazolam is usually administered intravenously; when minimal sedation is required, intranasal administration of midazolam is employed. Disease affects the pharmacokinetics of midazolam in neonates; multiple organ failure reduces the Cl of midazolam and mechanical ventilation prolongs the t_1/2 of this drug. ECMO therapy increases t_1/2, Cl, and Vd of midazolam several times. The adverse effects of midazolam in neonates are scarce: pain, tenderness, and thrombophlebitis may occur. Respiratory depression and hypotension appear in a limited percentage of infants following intravenous infusion of midazolam. In conclusion, midazolam is a safe and effective drug which is employed as a sedative, as antiepileptic agent, for infants who are refractory to standard antiepileptic therapy, and as an anaesthetic.

Psychometric evaluation of the Sophia Observation withdrawal symptoms scale in critically ill children

OBJECTIVE

The Sophia Observation withdrawal Symptoms scale is an instrument for screening benzodiazepine and opioid withdrawal syndrome in pediatric critical care patients. The objectives of this study were to establish cutoff scores and to test sensitivity to change. Second, risk factors for withdrawal syndrome were explored.

DESIGN

Prospective observational study with repeated measures.

SETTING

Level IV ICU at a university children's hospital.

PATIENTS

A total of 154 children with median age 5 months (interquartile range, 0-42 mo) who received continuous infusion of benzodiazepines and/or opioids for 5 or more days.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Nurses repeatedly applied the Sophia Observation withdrawal Symptoms scale and the Numeric Rating Scale withdrawal when children were weaned off benzodiazepines and opioids. The latter represents the nurse's expert opinion. We analyzed 3,754 paired assessments; the median number per child was 15 (interquartile range, 7-31) over a median of 5 days (interquartile range, 3-11 d). Sensitivity and specificity were 0.83 and 0.93, respectively, for the Sophia Observation withdrawal Symptoms scale cutoff score of 4 or higher against a Numeric Rating Scale-withdrawal score of 4 or higher. Sensitivity to change was determined by comparing 156 Sophia Observation withdrawal Symptoms scale assessments (n = 51 patients) before and after additional sedatives or opioids. Multilevel regression analysis showed a mean decline of 1.5 points (at score range 0-15) after intervention (p < 0.0001). Logistic regression analysis identified duration of preweaning of midazolam, duration of weaning of midazolam, duration of preweaning of morphine, duration of weaning of morphine, and number of additional sedatives/opioids as statistically significant risk factors for withdrawal syndrome in these children.

CONCLUSIONS

The Sophia Observation withdrawal Symptoms scale is a valid tool with good psychometric properties to assess withdrawal symptoms in PICU patients.

An evaluation of instruments for scoring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in pediatric mechanically ventilated patients: A systematic review

OBJECTIVES

Advancing technology allows for successful treatment of children with life-threatening illnesses. Effectively assessing and optimally treating a child's distress during their stay in the Pediatric Intensive Care Unit (PICU) is paramount. Objective measures of distress in mechanically ventilated pediatric patients are increasingly available but few have been evaluated. The objectives of this systematic review were to identify available instruments appropriate for measuring physiological and behavioral cues of pain, non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated pediatric patients, and evaluate these instruments in terms of their psychometric properties.

DESIGN

A systematic review of original and validation reports of objective instruments to measure pain and non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated PICU patients was undertaken.

DATA SOURCES

A comprehensive search was conducted in 10 databases from January 1970 to June 2011. Reference lists of relevant articles were reviewed to identify additional articles.

REVIEW METHODS

Studies were included in the review if they met pre-established eligibility criteria. Two independent reviewers reviewed studies for inclusion, assessed quality, and extracted data.

RESULTS

Twenty-five articles were included, identifying 15 instruments. The instruments had different foci including: assessing pain, non-pain related distress, and sedation (n=2); assessing pain exclusively (n=4); assessing sedation exclusively (n=7), assessing sedation in mechanically ventilated muscle relaxed PICU patients (n=1); and assessing delirium in mechanically ventilated PICU patients (n=1). The Comfort Scale demonstrated the greatest clinical utility in the assessment of pain, non-pain related distress, and sedation in mechanically ventilated pediatric patients. Modified FLACC and the MAPS are more appropriate, however, for the assessment of procedural pain and other brief painful events. More work is required on instruments for the assessment of distress in mechanically ventilated muscle relaxed PICU patients, and the assessment of delirium in PICU patients.

CONCLUSIONS

This review provides essential information to guide PICU clinicians in choosing instruments to assess pain, non-pain related distress, and adequacy of analgesia and sedation in mechanically ventilated pediatric patients. Effective knowledge translation is essential in the implementation, adoption, and successful use of these instruments.

Acetylcysteine and carbocysteine for acute upper and lower respiratory tract infections in paediatric patients without chronic broncho-pulmonary disease

BACKGROUND

Acetylcysteine and carbocysteine are the most commonly prescribed mucolytic drugs in Brazil and many European and African countries. To our knowledge, no systematic review has been published on their efficacy and safety for acute upper and lower respiratory tract infections (RTIs) in children without chronic broncho-pulmonary disease.

OBJECTIVES

The objective was to assess the efficacy and safety and to establish a benefit-risk ratio of acetylcysteine and carbocysteine as symptomatic treatments for acute upper and lower RTIs in paediatric patients without chronic broncho-pulmonary disease.

SEARCH METHODS

We searched CENTRAL (2013, Issue 2), MEDLINE (1966 to February week 3, 2013), EMBASE (1980 to March 2013), Micromedex (2010), Pascal (1987 to 2004) and Science Citation Index (1974 to March 2013).

SELECTION CRITERIA

To study efficacy, we used randomised controlled trials (RCTs) comparing the use of acetylcysteine or carbocysteine versus placebo, either alone or as an add-on therapy. To study safety, we used trials comparing acetylcysteine or carbocysteine versus active treatment or no treatment and case reports.

DATA COLLECTION AND ANALYSIS

In this review update two review authors (YD, MC), with help from a colleague, extracted data and assessed trial quality. We performed a subgroup analysis of children younger than two years of age.

MAIN RESULTS

We included six trials involving 497 participants to study efficacy. They showed some benefit (e.g. reduction of cough at day seven) from mucolytic agents, although differences were of little clinical relevance. No conclusion was drawn about the subgroup of infants younger than two years because data were unavailable. Thirty-four studies, including the previous six trials involving 2064 children, were eligible to study safety. Overall safety was good but very few data were available to evaluate safety in infants younger than two years. However, 59 cases of paradoxically increased bronchorrhoea observed in infants were reported to the French pharmacovigilance system.

AUTHORS' CONCLUSIONS

The results have to be interpreted with caution because they are based on a limited number of participants included in studies whose methodological quality is questionable. Acetylcysteine and carbocysteine seem to have a limited efficacy and appear to be safe in children older than two years. These results should take into consideration the fact that acetylcysteine and carbocysteine are prescribed for self limiting diseases (for example, acute cough, bronchitis). Given strong concerns about safety, these drugs should only be used for acute upper and lower RTIs in the context of a RCT with regards to children younger than two years.

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.

Biomarkers and clinical tools in critically ill children: are we heading toward tailored drug therapy?

In pediatric critical care, validated biomarkers are essential for guiding drug therapy. The aim of this article is to present examples of current biomarker developments in its full breadth, including biochemical substances, physiological measurements and clinical scoring tools, with a focus on the field of circulatory, renal and neurophysiologic failure. Within each field we consecutively discuss the rationale for the selected biomarkers, studies in critically ill children, biomarker validation stage and biomarker use or potential use in drug studies and clinical drug dosing. This article demonstrates that there is paucity of properly validated biomarkers. Nevertheless, recent developments in, for instance, the field of sepsis, point us toward a future wherein, for critically ill children, drug therapy may be personalized using proteomic profiling instead of a small number of biomarkers, in order to establish a personal and dynamic disease profile.

Abnormal Movements of Japanese Infants following Treatment with Midazolam in a Neonatal Intensive Care Unit: Incidence and Risk Factors

Background. This study was conducted to investigate the incidence of, and factors associated with, myoclonus-like abnormal movements of Japanese infants following treatment with midazolam in a neonatal intensive care unit (NICU). Methods. We retrospectively investigated abnormal movements and associated risk factors in Japanese infants (less than 1 year old) who received continuous intravenous midazolam treatment in the NICU of the Neonatal Medical Center, Kumamoto City Hospital, Japan, between April 2007 and March 2009. Results. The study included 94 infants who received 119 sessions of midazolam treatment in total. Nine infants (9.6%) developed abnormal movements attributable to midazolam. These nine patients had a significantly lower gestational age at birth, a significantly lower number of weeks after conception at the start of midazolam treatment, and significantly lower body weight compared with patients free of abnormal movements. Logistic regression analysis revealed neonatal asphyxia as a factor associated with an elevated risk of abnormal movements (P = 0.03). Conclusion. The incidence of abnormal movements after midazolam treatment was about 9.6% among the Japanese NICU infants. This result suggests that neonatal asphyxia may be involved in the onset of abnormal movements in infants treated with midazolam.

Blood concentrations of midazolam in status epilepticus using an appropriate condition of HPLC

BACKGROUND

The aim of the present study was to determine an index to evaluate the efficacy and safety of midazolam (MDZ) to treat status epilepticus (SE). An original system was therefore developed to measure blood concentrations of MDZ and 1-hydroxymidazolam (1-OHMDZ) as the main metabolite on high-performance liquid chromatography.

METHODS

This system was established through inspection of chromatograms, calibration curves and coefficient of correlations of MDZ. The clinical course of 11 SE patients, ranging from 4 months to 10 years of age, are described. These patients were treated with MDZ and measured at each blood concentration of MDZ. Moreover, patients were evaluated on cranial computed tomography and magnetic resonance imaging and video electroencephalogram (EEG), and it was determined that their seizures disappeared in accordance with the disappearance of convulsions and interictal EEG findings.

RESULTS

Reproducibility was good with this system. The standard curves of MDZ and 1-OHMDZ were almost straight, and the correlation coefficients of MDZ and 1-OHMDZ were r = 0.9999 and r = 0.9998, respectively. The convulsions in nine of 11 SE patients disappeared without side-effects and the blood concentrations of MDZ in all the patients were measured. The mean peak blood concentrations of MDZ and 1-OHMDZ were higher than those reported in other studies.

CONCLUSIONS

The clinical utility of this system has been demonstrated. An index to evaluate the efficacy and safety of MDZ is necessary, and MDZ blood concentrations measured on the present original precise measuring system could help in establishing a plan to successfully treat SE.

Feasibility of sedation and analgesia interruption following cannulation in neonates on extracorporeal membrane oxygenation

Purpose

In most extracorporeal membrane oxygenation (ECMO) centers patients are heavily sedated to prevent accidental decannulation and bleeding complications. In ventilated adults not on ECMO, daily sedation interruption protocols improve short- and long-term outcome. This study aims to evaluate safety and feasibility of sedation interruption following cannulation in neonates on ECMO.

Methods

Prospective observational study in 20 neonates (0.17–5.8 days of age) admitted for ECMO treatment. Midazolam (n = 20) and morphine (n = 18) infusions were discontinued within 30 min after cannulation. Pain and sedation were regularly assessed using COMFORT-B and visual analog scale (VAS) scores. Midazolam and/or morphine were restarted and titrated according to protocolized treatment algorithms.

Results

Median (interquartile range, IQR) time without any sedatives was 10.3 h (5.0–24.1 h). Median interruption duration for midazolam was 16.5 h (6.6–29.6 h), and for morphine was 11.2 h (6.7–39.4 h). During this period no accidental extubations, decannulations or bleeding complications occurred.

Conclusions

This is the first study to show that interruption of sedatives and analgesics following cannulation in neonates on ECMO is safe and feasible. Interruption times are 2–3 times longer than reported for adult ICU patients not on ECMO. Further trials are needed to substantiate these findings and evaluate short- and long-term outcomes.

Sedation and analgesia in the pediatric intensive care unit following laryngotracheal reconstruction

BACKGROUND

Children undergoing laryngotracheal reconstruction (LTR) may remain electively intubated in the pediatric intensive care unit (PICU) for several days following surgery to facilitate wound healing. These patients require sedation and analgesia with or without neuromuscular blockade in order to prevent excessive head and neck movement with resultant tension on the tracheal anastomosis. Achieving this level of immobility features in caring for these children.

AIM

The aims of this article are to describe a variety of commonly used sedation and analgesic agents and to provide guidance as to their optimal use following LTR.

Is anesthesia bad for the newborn brain?

Although certain data suggest that common general anesthetics may be neurotoxic to immature animals, there are also data suggesting that these same anesthetics may be neuroprotective against hypoxicischemic injury, and that inadequate analgesia during painful procedures may lead to increased neuronal cell death in animals and long-term behavioral changes in humans. The challenge for the pediatric anesthesia community is to design and implement studies in human infants to ascertain the safety of general anesthesia. In this article, the authors review the relevant preclinical and clinical data that are currently available on this topic.

Acetylcysteine and carbocysteine for acute upper and lower respiratory tract infections in paediatric patients without chronic broncho-pulmonary disease

BACKGROUND

Acetylcysteine and carbocysteine are the most commonly prescribed mucolytic drugs in many European countries. To our knowledge, no systematic review has been published on their efficacy and safety for acute upper and lower respiratory tract infections (ARTIs) in children without chronic broncho-pulmonary disease.

OBJECTIVES

The objective was to assess the efficacy and safety and to establish a benefit-risk ratio of acetylcysteine and carbocysteine as symptomatic treatments for ARTIs in children without chronic broncho-pulmonary disease.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, issue 4) which contains the Acute Respiratory Infections (ARI) Group's Specialized Register, MEDLINE (1966 to 2008), EMBASE (1980 to 2008); Micromedex (2008), Pascal (1987 to 2004), and Science Citation Index (1974 to 2008).

SELECTION CRITERIA

To study efficacy, we used randomised controlled trials (RCTs) comparing the use of acetylcysteine or carbocysteine versus placebo either alone or as an add-on therapy.To study safety, we also used trials comparing the use of acetylcysteine or carbocysteine versus active treatment or no treatment and case reports.

DATA COLLECTION AND ANALYSIS

At least two review authors extracted data and assessed trial quality. We performed a subgroup analysis of children younger than two years of age.

MAIN RESULTS

Six trials involving 497 participants were included to study efficacy. They showed some benefit from mucolytic agents, although differences were of little clinical relevance. No conclusion was drawn about the subgroup of infants younger than two years because the data were unavailable. Thirty-four studies including the previous six trials involving 2064 children were eligible to study safety. Overall safety was good but very few data were available to evaluate safety in infants younger than two years. However, 48 cases of paradoxically increased bronchorrhoea observed in infants were reported to the French pharmacovigilance system.

AUTHORS' CONCLUSIONS

The results of this review have to be interpreted with caution because it was based on a limited number of participants included in studies whose methodological quality is questionable. Acetylcysteine and carbocysteine seem to have a limited efficacy and appear to be safe in children older than two years. These results should take into consideration the fact that acetylcysteine and carbocysteine are prescribed for self-limiting diseases (for example, acute cough, bronchitis). Regarding children younger than two years, given concerns about safety, these drugs should only be used for ARTIs in the context of an RCT.

Sedation and analgesia in the pediatric Intensive Care Unit following laryngotracheal reconstruction

Deep levels of sedation and analgesia are needed in the majority of children who require prolonged tracheal intubation after laryngotracheal reconstruction (LTR). Drug doses may be determined most appropriately using validated scoring tools for sedation and analgesia; these scales continue to evolve and are used with increasing regularity in the pediatric intensive care unit (PICU). In this presentation, the validated scoring tools used to assess sedation and analgesia are reviewed, and specific agents used to manage sedation, analgesia, and neuromuscular blockade in the PICU after LTR are discussed.

Withdrawal symptoms in critically ill children after long-term administration of sedatives and/or analgesics: a first evaluation

OBJECTIVE

To establish frequencies of benzodiazepine and opioid withdrawal symptoms, and correlations with total doses and duration of administration.

DESIGN

A prospective, repeated-measures design.

SETTING

Two pediatric intensive care units in a university children's hospital.

PATIENTS

Seventy-nine children, aged 0 days to 16 yrs, who received intravenous midazolam and/or opioids for >5 days.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Pediatric intensive care unit nurses assessed withdrawal symptoms using the Sophia Benzodiazepine and Opioid Withdrawal Checklist, which includes all withdrawal symptoms (n = 24) described in the pediatric literature. Over 6 months, 2188 observations in 79 children were recorded. Forty-two percent of observations were performed within 24 hrs after tapering off or discontinuation of medication. Symptoms representing overstimulation of the central nervous system, such as anxiety, agitation, grimacing, sleep disturbance, increased muscle tension, and movement disorder, were observed in >10% of observations. Of symptoms reflecting gastrointestinal dysfunction, diarrhea and gastric retention were most frequently observed. Tachypnea, fever, sweating, and hypertension as manifestations of autonomic dysfunction were observed in >13% of observations. The Spearman's rank-correlation coefficient between total doses of midazolam and maximum sum score (of the Sophia Benzodiazepine and Opioid Withdrawal Checklist) was .51 (p < 0.001). The correlation between total doses of opioids and the maximum sum score was .39 (p < 0.01). A significant correlation (.52; p < 0.001) was also found between duration of use and maximum sum score.

CONCLUSIONS

This is the first study to report frequencies of all 24 withdrawal symptoms observed in children after decrease or discontinuation of benzodiazepines and/or opioids. Agitation, anxiety, muscle tension, sleeping <1 hr, diarrhea, fever, sweating, and tachypnea were observed most frequently. Longer duration of use and high dosing are risk factors for development of withdrawal symptoms in children.

Children's factual and delusional memories of intensive care

RATIONALE

Delusional memories are significantly associated with post-traumatic stress in adult patients after intensive care.

OBJECTIVES

In this study, we attempted to establish whether this relationship was found in children. We also examined the association between factual memory and distress.

METHODS

One hundred two consecutive children, aged between 7 and 17 years, were interviewed about their pediatric intensive care unit (PICU) experience 3 months after discharge from a PICU. Principal measures were the ICU Memory Tool (a checklist of intensive care memories) and an abbreviated version of the Impact of Event Scale (a screen for post-traumatic stress disorder).

MEASUREMENTS AND MAIN RESULTS

In total, 64 of 102 (63%) children reported at least one factual memory of their admission and 33 of 102 (32%) reported delusional memories, including disturbing hallucinations. Traumatic brain injury was negatively associated with factual memory (odds ratio, 0.23; 95% confidence interval [CI], 0.09-0.58; P = 0.002). Longer duration of opiates/benzodiazepines was associated with delusional memory (odds ratio, 4.98; 95% CI, 1.3-20.0; P = 0.023). Post-traumatic stress scores were higher in children reporting delusional memories (adjusted difference, 3.0; 95% CI, 0.06-5.9; P = 0.045) when illness severity and emergency status were controlled for. Factual memory was not significantly associated with post-traumatic stress.

CONCLUSIONS

This study indicates that delusional memories are reported by almost one-third of children and are associated both with the duration of opiates/benzodiazepines and risk of post-traumatic stress. More research is needed on the presence of delusional memories and associated risk factors in children receiving intensive care treatment.

Orofacial automatisms induced by acute withdrawal from high-dose midazolam mimicking nonconvulsive status epilepticus in a child

Nonconvulsive Status Epilepticus (NCSE) is not uncommon in children, and can be challenging to diagnose and treat. Etiologies vary widely and include infection, trauma and acute withdrawal from medications such as anticonvulsants. We report a child who experienced orofacial dyskinesias concerning for NCSE after withdrawal from high dose benzodiazepines andopiates. Automonic signs typically associated with sedative withdrawal were absent and treatment with benzodiazepines did not improve his symptoms. Diagnostic testing was negative, including electroencephalogram, and resolution was complete within five days. Our case demonstrates the orofacial dyskinesias that may occur during sedative medication withdrawal, and highlights potential confusion with non-convulsive status epilepticus.

Current United Kingdom sedation practice in pediatric intensive care

BACKGROUND

The aim of this study was to investigate the current practice of sedation, analgesia, and neuromuscular blockade in critically ill children on pediatric intensive care units (PICUs) in the UK and identify areas that merit further study.

METHODS

Data were gathered in a prospective observational study of 338 critically ill children in 20 UK PICUs.

RESULTS

There is considerable variation in clinical practice. A total of 24 different sedative and analgesic agents were used during the study. The most commonly used sedative and analgesic agents were midazolam and morphine. Four different neuromuscular blockers (NMBs) were used, most commonly vecuronium. There were differences in treatment between cardiac and noncardiac children, but there were a greater number of infants and neonates in the cardiac group. NMBs were used in 30% of mechanically ventilated patients. Withdrawal symptoms were reported in 13% of ventilated patients, relatively early in their stay; weaning sedative agents ('tapering') was apparently of no benefit. The use of clonidine in this setting was noted. Physical restraints were used in 7.4%. Propofol was used but in only 2.6% of patients, all over the age of 4 years, and not exceeding 2 mgxkg(-1)xh(-1). No side effects attributable to 'propofol syndrome' were noted.

CONCLUSIONS

There is considerable heterogeneity of sedation techniques. NMBs are used in a large portion of this population. Withdrawal symptoms were associated with higher doses of sedation and greater lengths of stay and were not ameliorated by withdrawing sedation gradually ('tapering').

Withdrawal symptoms in children after long-term administration of sedatives and/or analgesics: a literature review. "Assessment remains troublesome"

BACKGROUND

Prolonged administration of benzodiazepines and/or opioids to children in a pediatric intensive care unit (PICU) may induce physiological dependence and withdrawal symptoms.

OBJECTIVE

We reviewed the literature for relevant contributions on the nature of these withdrawal symptoms and on availability of valid scoring systems to assess the extent of symptoms.

METHODS

The databases PubMed, CINAHL, and Psychinfo (1980-June 2006) were searched using relevant key terms.

RESULTS

Symptoms of benzodiazepine and opioid withdrawal can be classified in two groups: central nervous system effects and autonomic dysfunction. However, symptoms of the two types show a large overlap for benzodiazepine and opioid withdrawal. Symptoms of gastrointestinal dysfunction in the PICU population have been described for opioid withdrawal only. Six assessment tools for withdrawal symptoms are used in children. Four of these have been validated for neonates only. Two instruments are available to specifically determine withdrawal symptoms in the PICU: the Sedation Withdrawal Score (SWS) and the Opioid Benzodiazepine Withdrawal Scale (OBWS). The OBWS is the only available assessment tool with prospective validation; however, the sensitivity is low.

CONCLUSIONS

Withdrawal symptoms for benzodiazepines and opioids largely overlap. A sufficiently sensitive instrument for assessing withdrawal symptoms in PICU patients needs to be developed.

Withdrawal from lorazepam in critically ill children

BACKGROUND

Sedatives are used in critically ill children to facilitate mechanical ventilation. Although tolerance and withdrawal are associated with use of sedatives, information about withdrawal from benzodiazepines in children is limited.

OBJECTIVE

To document the occurrence of lorazepam withdrawal in critically ill children and identify predictors for the development of withdrawal.

METHODS

This prospective, investigational, open-label study enrolled pediatric patients receiving a continuous infusion of lorazepam for at least 72 hours. The lorazepam dosage was tapered in a uniform fashion over 6 days by decreasing the total daily dose by 50% every other day on 3 occasions; it was then discontinued. The occurrence of withdrawal from lorazepam was determined by pediatric intensive care unit attending physicians based on clinical judgment. Patients were assessed for withdrawal twice daily beginning 48 hours after the initiation of the lorazepam taper. Assessments were continued for 72 hours after lorazepam discontinuation or until the patient experienced withdrawal, whichever came first. Patient demographic, sedative dosing, and lorazepam serum concentration data were collected to identify risk factors for withdrawal.

RESULTS

Twenty-nine patients completed the study. They received lorazepam for a median duration of about 21 days, and withdrawal occurred in 7 patients. There were no significant differences in demographic variables, lorazepam dosage or other sedative therapy, or lorazepam serum concentrations between patients with withdrawal and those without withdrawal. No predictors of withdrawal were identified.

CONCLUSIONS

Withdrawal occurred in 24% of critically ill children receiving long-term sedation from lorazepam. Risk factors for withdrawal are unknown.