Predictors of airway and respiratory adverse events with ketamine sedation in the emergency department: an individual-patient data meta-analysis of 8,282 children

Pediatric sedation: a global challenge

Pediatric sedation is a challenge which spans all continents and has grown to encompass specialties outside of anesthesia, radiology and emergency medicine. All sedatives are not universally available and local and national regulations often limit the sedation practice to specific agents and those with specific credentials. Some specialties have established certification and credentials for sedation delivery whereas most have not. Some of the relevant sedation guidelines and recommendations of specialty organizations worldwide will be explored. The challenge facing sedation care providers moving forward in the 21st century will be to determine how to apply the local, regional and national guidelines to the individual sedation practices. A greater challenge, perhaps impossible, will be to determine whether the sedation community can come together worldwide to develop standards, guidelines and recommendations for safe sedation practice.

Wherefore ketamine?

PURPOSE OF REVIEW

Ketamine has been repeatedly reviewed in this journal but novel developments have occurred in the last few years prompting an update. Interesting recent publications will be highlighted against a background of established knowledge.

RECENT FINDINGS

In the field of anesthesia, particularly in pediatrics, some contributions have been made concerning intramuscular versus intravenous induction. The need for anticholinergic adjuvants has also been clarified. Neuroapoptosis has been observed in animals and its implications for human subjects are discussed in a general context of neurotoxicity. The most important developments, however, are in the treatment of pain. Neurological and urological side effects strongly question long-term use. Other potentially beneficial effects have also been reported, such as anti-inflammatory and antidepressive effects. There are also indications that ketamine may attenuate postoperative delirium in coronary by-pass patients.

SUMMARY

More questions have arisen than have been answered. Some have very grave implications. The issue of neuroapoptosis must be clarified. The long-term effects must be further investigated. On the bright side the effects on postoperative delirium, as well as the anti-inflammatory and antidepressive effects, might open new vistas for an old drug.

Intravenous vs intramuscular ketamine for pediatric procedural sedation by emergency medicine specialists: a review

Ketamine is a general anesthetic agent widely used for pediatric procedural sedation outside the operating theater by nonanesthesiologists. In a setting where efficacy and safety of the agent are paramount, there are conflicting recommendations in terms of optimal mode of parenteral administration, as well as optimal dosage and need for the coadministration of adjunctive agents to decrease side effects. We investigated existing evidence to determine whether ketamine should be best administered intravenously or intramuscularly. This analysis was made difficult by limited direct comparisons of both modes of parenteral administration and a lack of consistent definitions for key outcomes such as 'effectiveness,''adverse events,''hypoxia,''ease of completion of the procedure,' and 'satisfaction' across studies that have evaluated ketamine. Based on large data sets, the safety and efficacy of both modes of administration are broadly similar. Although data on head to head comparisons of intravenous and intramuscular ketamine is limited, based on our analysis, we conclude that the trends indicate ketamine is ideally administered intravenously.

Professional skills and competence for safe and effective procedural sedation in children: recommendations based on a systematic review of the literature

Objectives. To investigate which skills and competence are imperative to assure optimal effectiveness and safety of procedural sedation (PS) in children and to analyze the underlying levels of evidence. Study Design and methods. Systematic review of literature published between 1993 and March 2009. Selected papers were classified according to their methodological quality and summarized in evidence-based conclusions. Next, conclusions were used to formulate recommendations. Results. Although the safety profiles vary among PS drugs, the possibility of potentially serious adverse events and the predictability of depth and duration of sedation define the imperative skills and competence necessary for a timely recognition and appropriate management. The level of effectiveness is mainly determined by the ability to apply titratable PS, including deep sedation using short-acting anesthetics for invasive procedures and nitrous oxide for minor painful procedures, and the implementation of non-pharmacological techniques. Conclusions. PS related safety and effectiveness are determined by the circumstances and professional skills rather than by specific pharmacologic characteristics. Evidence based recommendations regarding necessary skills and competence should be used to set up training programs and to define which professionals can and cannot be credentialed for PS in children.

Procedural Sedation and Analgesia in Children: Perspectives from Paediatric Emergency Physicians

Procedural sedation and analgesia in children is now widely practised in many emergency departments internationally. In this article, we address the general principles, indications, guidelines, medications, adverse events and future research in paediatric procedural sedation and analgesia in the Emergency Department.

Procedural sedation and analgesia is the use of sedative, analgesia and dissociative drugs to provide anxiolysis, analgesia, sedation and motor control during painful or unpleasant diagnostic and therapeutic procedures. It is a continuous spectrum from mild, moderate, deep sedation and then general anaesthesia. Dissociative sedation from ketamine is also commonly used.

Internationally, major clinical guidelines have been issued and revised since the 1980s. The guidelines should include the following components and documentation: pre-sedation assessment, intra-procedural monitoring and post-procedural monitoring and discharge criteria. The pre-sedation assessment involves assessing suitability of patient as candidate for sedation, any contraindications, fasting time, ensuring that the necessary equipment and drugs are available and the personnel providing the sedation are skilled in sedation and resuscitation.

The common medications for sedation in the emergency departments include ketamine, midazolam, fentanyl, morphine, oral chloral hydrate and nitrous oxide inhalation. Propofol and etomidate are used widely in some of the paediatric emergency departments internationally.

Procedural sedation has been documented to be safe and effective when performed by trained emergency physicians. The overall incidence of complications was 5.3% in a large prospective study, including airway and respiratory events (laryngospasm, apnoea, desaturations) and emesis. Aspirations are rare complications. Though the risks of adverse events are not high, emergency physicians need to have core competencies in sedation and resuscitation skills. The future of procedural sedation and analgesia will focus on enhancing training, safety and effectiveness.

Randomized clinical trial of propofol versus ketamine for procedural sedation in the emergency department

OBJECTIVES

The objective was to compare the occurrence of respiratory depression, adverse events, and recovery duration of propofol versus ketamine for use in procedural sedation in the emergency department (ED).

METHODS

This was a randomized nonblinded prospective clinical trial of adult patients undergoing procedural sedation for painful procedures in the ED. Patients with pain before the procedure were treated with intravenous (IV) morphine sulfate until their pain was adequately treated at least 20 minutes before starting the procedure. Patients were randomized to receive either propofol 1 mg/kg IV followed by 0.5 mg/kg every 3 minutes as needed or ketamine 1.0 mg/kg IV followed by 0.5 mg/kg every 3 minutes as needed. Doses, vital signs, nasal end-tidal CO(2) (ETCO(2)), and pulse oximetry were recorded. Subclinical respiratory depression was defined as a change in ETCO(2) of >10 mm Hg, an oxygen saturation of <92% at any time, or an absent ETCO(2) waveform at any time. Clinical interventions related to respiratory depression were noted during the procedure, including the addition of or increase in the flow rate of supplemental oxygen, the use of a bag-valve mask apparatus, airway repositioning, or stimulation to induce breathing. After the procedure, patients were asked if they experienced pain during the procedure and had recall of the procedure. Physicians were asked to describe any adverse events or the occurrence of recovery agitation.

RESULTS

One-hundred patients were enrolled; 97 underwent sedation and were included in the analysis. Fifty patients received propofol and 47 received ketamine. Subclinical respiratory depression was seen in 20 of 50 patients in the propofol group and 30 of 47 patients in the ketamine group (p = 0.019, effect size 22.8%; 95% CI = 4.0% to 43.6%). Clinical interventions related to respiratory depression were used in 26 of 50 propofol patients and 19 of 47 ketamine patients (p = 0.253, effect size = -13.7%; 95% CI = -33.8% to 6.4%). The median times of the procedures were 11 minutes (range = 4 to 33 minutes) for the ketamine group versus 10 minutes (range = 5 to 33 minutes) for the propofol group (p = 0.256). The median time to return to baseline mental status after the procedure was completed was 14 minutes (range = 2 to 47 minutes) for the ketamine group and 5 minutes (range = 1 to 32 minutes) for the propofol group (p < 0.001). Pain during the procedure was reported by 3 of 50 patients in the propofol group and 1 of 47 patients in the ketamine group (effect size = -3.9%, 95% confidence interval [CI] = -11.9 to 4.1). Recall of some part of the procedure was reported by 4 of 50 patients in the propofol group and 6 of 47 patients in the ketamine group (effect size = 4.8%, 95% CI = -7.6% to 17.1%). Forty-eight of 50 procedures were successful in the propofol group and 43 of 47 in the ketamine group (p = 0.357, effect size = 0.3%; 95% CI = -7.8% to 8.4%). Recovery agitation was reported in 4 of 50 in the propofol group and 17 of 47 in the ketamine group (effect size = 28.2%, 95% CI = 12.4% to 43.9%).

CONCLUSIONS

This study detected a higher rate of subclinical respiratory depression in patients in the ketamine group than the propofol group. There was no difference in the rate of clinical interventions related to respiratory depression, pain, or recall of the procedure between the groups. Recovery agitation was seen more frequently in patients receiving ketamine than in those receiving propofol. The time to regain baseline mental status was longer in the ketamine group than the propofol group. This study suggests that the use of either ketamine or propofol is safe and effective for procedural sedation in the ED.

A prospective case series of pediatric procedural sedation and analgesia in the emergency department using single-syringe ketamine-propofol combination (ketofol)

OBJECTIVES

This study evaluated the effectiveness, recovery time, and adverse event profile of intravenous (IV) ketofol (mixed 1:1 ketamine-propofol) for emergency department (ED) procedural sedation and analgesia (PSA) in children.

METHODS

Prospective data were collected on all PSA events in a trauma-receiving, community teaching hospital over a 3.5-year period, from which data on all patients under 21 years of age were studied. Patients receiving a single-syringe 1:1 mixture of 10 mg/mL ketamine and 10 mg/mL propofol (ketofol) were analyzed. Patients received ketofol in titrated aliquots at the discretion of the treating physician. Effectiveness, recovery time, caregiver and patient satisfaction, drug doses, physiologic data, and adverse events were recorded.

RESULTS

Ketofol PSA was performed in 219 patients with a median age of 13 years (range = 1 to 20 years; interquartile range [IQR] = 8 to 16 years) for primarily orthopedic procedures. The median dose of medication administered was 0.8 mg/kg each of ketamine and propofol (range = 0.2 to 3.0 mg/kg; IQR = 0.7 to 1.0 mg/kg). Sedation was effective in all patients. Three patients (1.4%; 95% confidence interval [CI] = 0.0% to 3.0%) had airway events requiring intervention, of which one (0.4%; 95% CI = 0.0% to 1.2%) required positive pressure ventilation. Two patients (0.9%; 95% CI = 0.0% to 2.2%) had unpleasant emergence requiring treatment. All other adverse events were minor. Median recovery time was 14 minutes (range = 3 to 41 minutes; IQR = 11 to 18 minutes). Median staff satisfaction was 10 on a 1-to-10 scale.

CONCLUSIONS

Pediatric PSA using ketofol is highly effective. Recovery times were short; adverse events were few; and patients, caregivers, and staff were highly satisfied.

Anticholinergics and ketamine sedation in children: a secondary analysis of atropine versus glycopyrrolate

OBJECTIVES

Adjunctive anticholinergics are commonly administered during emergency department (ED) ketamine sedation in children under the presumption that drying oral secretions should decrease the likelihood of airway and respiratory adverse events. Pharmacologic considerations suggest that glycopyrrolate might exhibit a superior adverse effect profile to atropine. The authors contrasted the adverse events noted with use of each of these anticholinergics in a large multicenter observational database of ketamine sedations.

METHODS

This was a secondary analysis of an observational database of 8,282 ED ketamine sedations assembled from 32 prior series. The authors compared the relative incidence of six adverse events (airway and respiratory adverse events, laryngospasm, apnea, emesis, recovery agitation, and clinically important recovery agitation) between children who received coadministered atropine, glycopyrrolate, or no anticholinergic. Multivariable analysis using the specific anticholinergic as a covariate was performed, while controlling for other known predictors.

RESULTS

Atropine was associated with less vomiting (5.3%) than either glycopyrrolate (10.7%) or no anticholinergic (11.4%) in both unadjusted and multivariable analyses. Glycopyrrolate was associated with significantly more airway and respiratory adverse events (6.4%) than either atropine (3.3%) or no anticholinergic (3.0%) and similarly more clinically important recovery agitation (2.1% vs. 1.2 and 1.3%). There were, however, no differences noted in odds of laryngospasm and apnea.

CONCLUSIONS

This secondary analysis unexpectedly found that the coadministered anticholinergic atropine exhibited a superior adverse event profile to glycopyrrolate during ketamine sedation. Any such advantage requires confirmation in a separate trial; however, our data cast doubt on the traditional premise that glycopyrrolate might be superior. Further, neither anticholinergic showed efficacy in decreasing airway and respiratory adverse events.

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.