Baruch Krauss

Procedural sedation and analgesia in children

Procedural sedation and analgesia for children--the use of sedative, analgesic, or dissociative drugs to relieve anxiety and pain associated with diagnostic and therapeutic procedures--is now widely practised by a diverse group of specialists outside the operating theatre. We review the principles underlying safe and effective procedural sedation and analgesia and the spectrum of procedures for which it is currently done. We discuss the decision-making process used to determine appropriate drug selection, dosing, and sedation endpoint. We detail the pharmacopoeia for procedural sedation and analgesia, reviewing the pharmacology and adverse effects of these drugs. International differences in practice are described along with current areas of controversy and future directions.

Clinical practice guideline for emergency department ketamine dissociative sedation: 2011 update.

We update an evidence-based clinical practice guideline for the administration of the dissociative agent ketamine for emergency department procedural sedation and analgesia. Substantial new research warrants revision of the widely disseminated 2004 guideline, particularly with respect to contraindications, age recommendations, potential neurotoxicity, and the role of coadministered anticholinergics and benzodiazepines. We critically discuss indications, contraindications, personnel requirements, monitoring, dosing, coadministered medications, recovery issues, and future research questions for ketamine dissociative sedation.

Preprocedural fasting state and adverse events in children undergoing procedural sedation and analgesia in a pediatric emergency department

STUDY OBJECTIVE Assessment of preprocedural fasting is considered essential in minimizing the risks of procedural sedation and analgesia. Established fasting guidelines are difficult to follow in the emergency department (ED). We characterize the fasting status of patients receiving procedural sedation and analgesia in a pediatric ED and assess the relationship between fasting status and adverse events. METHODS A prospective case series was conducted in a childrens hospital ED during an 11-month period. All consecutive patients requiring procedural sedation and analgesia were included. Preprocedural fasting state and adverse events were recorded. The percentage of patients undergoing procedural sedation and analgesia who did not meet fasting guidelines was determined. Adverse events were analyzed in relation to fasting status. RESULTS One thousand fourteen patients underwent procedural sedation and analgesia, and data on fasting status were available for 905 (89%) patients. Of these 905 patients, 509 (56%; 95% confidence interval [CI] 53% to 60%) did not meet fasting guidelines. Seventy-seven adverse events occurred in 68 (6.7%; 95% CI 5.2% to 8.4%) of the 1,014 patients. All adverse events were minor and successfully treated. Adverse events occurred in 32 (8.1%; 95% CI 5.6% to 11.2%) of 396 patients who met and 35 (6.9%; 95% CI 4.8% to 9.4%) of 509 patients who did not meet fasting guidelines. There was no significant difference in median fasting duration between patients with and without adverse events and between patients with and without emesis. Emesis occurred in 15 (1.5%) patients. There were no episodes of aspiration (1-sided 97.5% CI 0% to 0.4%). CONCLUSION Fifty-six percent of children undergoing ED procedural sedation and analgesia were not fasted in accordance with established guidelines. There was no association between preprocedural fasting state and adverse events.

Predictors of Airway and Respiratory Adverse Events With Ketamine Sedation in the Emergency Department: An Individual-Patient Data Meta-analysis of 8,282 Children

STUDY OBJECTIVE Although ketamine is one of the most commonly used sedatives to facilitate painful procedures for children in the emergency department (ED), existing studies have not been large enough to identify clinical factors that are predictive of uncommon airway and respiratory adverse events. METHODS We pooled individual-patient data from 32 ED studies and performed multiple logistic regressions to determine which clinical variables would predict airway and respiratory adverse events. RESULTS In 8,282 pediatric ketamine sedations, the overall incidence of airway and respiratory adverse events was 3.9%, with the following significant independent predictors: younger than 2 years (odds ratio [OR] 2.00; 95% confidence interval [CI] 1.47 to 2.72), aged 13 years or older (OR 2.72; 95% CI 1.97 to 3.75), high intravenous dosing (initial dose > or =2.5 mg/kg or total dose > or =5.0 mg/kg; OR 2.18; 95% CI 1.59 to 2.99), coadministered anticholinergic (OR 1.82; 95% CI 1.36 to 2.42), and coadministered benzodiazepine (OR 1.39; 95% CI 1.08 to 1.78). Variables without independent association included oropharyngeal procedures, underlying physical illness (American Society of Anesthesiologists class >or = 3), and the choice of intravenous versus intramuscular route. CONCLUSION Risk factors that predict ketamine-associated airway and respiratory adverse events are high intravenous doses, administration to children younger than 2 years or aged 13 years or older, and the use of coadministered anticholinergics or benzodiazepines.

The spectrum and frequency of illness presenting to a pediatric emergency department.

Knowledge of the spectrum and relative frequencies of pediatric emergencies is an important factor in developing appropriate training curricula for physicians treating children in emergency departments. To provide these data, we reviewed the records for four one-week periods (January, April, July, and October) of a large pediatric emergency department to describe the population in terms of age, chief complaints, diagnoses, time of arrival, seasonal variation, and disposition. There were 3796 log entries. Complete information on all variables was obtained on 3784 patients. Age ranged from one day to 39 years, and the mean age was 6.0 ± 6.15 years. One half of all emergency department visits were by children three years old or younger. On the other hand, 12% of visits were by adolescents (ages 13 to 18), and one in 25 visits was made by an adult (>18 years old). The majority of chief complaints and final diagnoses were related to infection and trauma. More than half of the patients arrived on the evening shift, between 4 pm and 12 am. Eleven percent of the children seen on day and evening shifts and 13% from the night shift were admitted. From the analysis of our data we recommend expanded skills in the management of minor trauma for pediatric residents, an emphasis on management of infections for nonpediatric emergency specialists, and extensive training in both pediatric and adult trauma for physicians in pediatric emergency medicine fellowships.

Consensus-Based Recommendations for Standardizing Terminology and Reporting Adverse Events for Emergency Department Procedural Sedation and Analgesia in Children

Children commonly require sedation and analgesia for procedures in the emergency department. Establishing accurate adverse event and complications rates from the available literature has been difficult because of the difficulty in aggregating results from previous studies that have used varied terminology to describe the same adverse events and outcomes. Further, serious adverse events occur infrequently, necessitating the study of large numbers of children to assess safety. These limitations prevent the establishment of a sufficiently large database on which evidence-based practice guidelines may be based. We assembled a panel of pediatric sedation researchers and experts to develop consensus-based recommendations for standardizing procedural sedation and analgesia terminology and reporting of adverse events. Our goal was to create a uniform reporting mechanism for future studies to facilitate the aggregation and comparison of results.

Microstream Capnography Technology: A New Approach to an Old Problem

Significant technical limitations inherent in blackbody infrared technology used in conventional sidestream and mainstream capnography have hindered the acceptance and growth of capnography as a monitoring tool outside the operating room environment. We describe a new technology (Microstream™) for CO2 monitoring, based on molecular correlation spectroscopy, which results in a highly efficient and selective emission of a spectrum of discrete wavelengths exactly matching those for CO2 absorption. The CO2 specific emissions allow for an extremely small sample cell (15 µl), which in turn, permits the use of a very low sample flow rate (50 ml/min) without compromising waveform integrity or end-tidal CO2 accuracy. Design and technology features of the CO2 emission source, sample cell, and breath sampling circuits are described.

Predictors of Emesis and Recovery Agitation With Emergency Department Ketamine Sedation: An Individual-Patient Data Meta-Analysis of 8,282 Children

STUDY OBJECTIVE Ketamine is widely used in emergency departments (EDs) to facilitate painful procedures; however, existing descriptors of predictors of emesis and recovery agitation are derived from relatively small studies. METHODS We pooled individual-patient data from 32 ED studies and performed multiple logistic regression to determine which clinical variables would predict emesis and recovery agitation. The first phase of this study similarly identified predictors of airway and respiratory adverse events. RESULTS In 8,282 pediatric ketamine sedations, the overall incidence of emesis, any recovery agitation, and clinically important recovery agitation was 8.4%, 7.6%, and 1.4%, respectively. The most important independent predictors of emesis are unusually high intravenous (IV) dose (initial dose of > or =2.5 mg/kg or a total dose of > or =5.0 mg/kg), intramuscular (IM) route, and increasing age (peak at 12 years). Similar risk factors for any recovery agitation are low IM dose (<3.0 mg/kg) and unusually high IV dose, with no such important risk factors for clinically important recovery agitation. CONCLUSION Early adolescence is the peak age for ketamine-associated emesis, and its rate is higher with IM administration and with unusually high IV doses. Recovery agitation is not age related to a clinically important degree. When we interpreted it in conjunction with the separate airway adverse event phase of this analysis, we found no apparent clinically important benefit or harm from coadministered anticholinergics and benzodiazepines and no increase in adverse events with either oropharyngeal procedures or the presence of substantial underlying illness. These and other results herein challenge many widely held views about ED ketamine administration.

IgE-mediated food allergy in children

Food allergy is a serious health issue affecting roughly 4% of children, with a substantial effect on quality of life. Prognosis is good for the most frequent allergens with almost all children outgrowing their allergy. However, the long-term implications for disease burden are substantial for children with persistent allergies (eg, peanuts, tree nuts, fish, and shellfish) and for those with high concentrations of milk, egg, and wheat IgE. Antigen avoidance has been the time-honoured approach both for prevention and treatment. However, findings from studies done in the past 5 years show that early contact with food can induce tolerance and desensitisation to foods. We review the epidemiology, natural history, and management of food allergy, and discuss the areas of controversy and future directions in research and clinical practice.

Bispectral index monitoring quantifies depth of sedation during emergency department procedural sedation and analgesia in children.

STUDY OBJECTIVE The bispectral index monitor uses processed electroencephalogram signals to measure sedation depth on a unitless scale from 0 to 100 (0, coma; 40 to 60, general anesthesia; 60 to 90, sedated; 100, awake). It has been validated in the operating room as an objective measure of sedation depth with nondissociative general anesthesia; however, its usefulness in the pediatric emergency department (ED) for procedural sedation and analgesia has not been established. We determine the ability of the bispectral index to monitor depth of nondissociative procedural sedation and analgesia in children. METHODS This was an observational study conducted in a childrens hospital ED. Procedural sedation and analgesia was performed in the standard manner, with the addition of bispectral index monitoring and simultaneous clinical sedation scoring (modified Ramsay Sedation Scale [range 1 to 8; 1=alert, 8=unresponsive]). Paired bispectral index and Ramsay Sedation Scale scores were assigned every 5 minutes during the sedation. Ramsay Sedation Scale scores were assigned by a single study investigator blinded to the bispectral index score. An emergency physician independently administered all medications for procedural sedation and analgesia. The correlation between the paired bispectral index/Ramsay Sedation Scale scores was determined by using a repeated-measures regression analysis. Receiver operator characteristic (ROC) curves were constructed to determine the ability of the bispectral index to discriminate various thresholds of sedation depth. RESULTS A convenience sample of 20 patients was enrolled, providing 217 paired bispectral index/Ramsay Sedation Scale measurements. Median age was 4.6 years (range 0.4 to 16.7 years). Fourteen patients received midazolam with fentanyl; the remainder received pentobarbital. Bispectral index scores ranged from 40 to 98 (mean 81.6+/-16.1). Ramsay Sedation Scale scores ranged from 1 to 8 (median 3; interquartile range 2 to 4). The simple Pearson correlation between paired bispectral index and Ramsay Sedation Scale scores was -0.78 (95% confidence interval [CI] -0.83 to -0.72; P<.001). After adjustment for the nonindependence of intrapatient data with bivariate repeated-measures analysis, the correlation was -0.67 (95% CI -0.90 to -0.43; P<.001). The linear regression coefficient between bispectral index and Ramsay Sedation Scale scores was estimated to be between -5.7 and -12.7. ROC curve analysis demonstrated moderate to high discriminatory power of bispectral index scores in predicting level of sedation throughout the sedation continuum, with areas under the curve at least 0.87 for all Ramsay Sedation Scale score thresholds. Bispectral index scores between 60 and 90 predicted with moderate accuracy traditional clinical levels of sedation typically encountered during procedural sedation and analgesia in the pediatric ED. CONCLUSION Bispectral index monitoring correlated with clinical sedation scores and may serve as a useful, objective adjunct in quantifying depth of nondissociative procedural sedation and analgesia in children.