Sedation with meperidine and midazolam in pediatric patients undergoing endoscopy

What is the level of evidence for the amnestic effects of sedatives in pediatric patients? A systematic review and meta-analyses

Background

Studies have suggested that benzodiazepines are amnestic drug par excellence, but when taken together, what level of evidence do they generate? Are other sedatives as amnestic as benzodiazepines? The aim of this study was to assess the level of scientific evidence for the amnestic effect of sedatives in pediatric patients who undergo health procedures.

Methods

The literature was searched to identify randomized controlled trials that evaluated anterograde and retrograde amnesia in 1-19-year-olds who received sedative drugs during health procedures. Electronic databases, including PubMed, Scopus and Cochrane Library besides clinical trial registries and grey literature were searched. Two independent reviewers performed data extraction and risk of bias assessment using the Cochrane Collaboration's Tool. The meta-analyses were performed by calculating relative risk (RR) to 95% confidence intervals (CI). The quality of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation approach.

Results

Fifty-four studies were included (4,168 participants). A higher occurrence of anterograde amnesia was observed when benzodiazepines, the most well-studied sedatives (n = 47), were used than when placebo was used (n = 12) (RR = 3.10; 95% CI: 2.30–4.19, P<0.001; I² = 14%), with a moderate level of evidence. Higher doses of alpha2-adrenergic agonists (clonidine/dexmedetomidine) produced more anterograde amnesia than lower doses (n = 2) (RR = 1.83; 95% CI: 1.03–3.25; P = 0.038; I² = 0%), with a low level of evidence; benzodiazepines’ amnestic effects were not dose-dependent (n = 3) (RR = 1.54; 95% CI: 0.96–2.49; P = 0.07; I² = 12%) but the evidence was low. A qualitative analysis showed that retrograde amnesia did not occur in 8 out of 10 studies.

Conclusions

In children, moderate evidence support that benzodiazepines induce anterograde amnesia, whereas the evidence for other sedatives is weak and based on isolated and small studies. Further clinical trials focused on the amnesia associated with non-benzodiazepine sedatives are therefore needed.

Trial registration

PROSPERO CRD42015017559.

Il lavaggio broncoalveolare (BAL) in età pediatrica

Il lavaggio broncoalveolare o BAL, permettendo di ottenere le cellule ed i soluti presenti sulla superficie epiteliale del tratto respiratorio distale, si è dimostrato una metodica di ricerca essenziale per lo studio dei meccanismi eziopatogenetici delle malattie del polmone profondo, come ad esempio lo studio delle interstiziopatie, su cui esiste una vastissima letteratura di dati ottenuti con il BAL. Oltre a questo aspetto di metodica di ricerca, il BAL rappresenta perè anche una procedura diagnostica insostituibile nella pratica clinica quotidiana.

Paradoxical reaction following intravenous midazolam premedication in pediatric patients - a randomized placebo controlled trial of ketamine for rapid tranquilization

BACKGROUND

Paradoxical reactions to benzodiazepines include restlessness, violent behavior, physical assault, act of self-injury and need for restraints. These may occur at variable times after administration. This study was designed to determine the incidence of paradoxical reactions following intravenous midazolam premedication in pediatric patients and to compare the efficacy of extra doses of midazolam with low-dose intravenous ketamine to rapidly tranquillize them.

METHODS

A total of 706 ASA I, II children scheduled for elective surgery were given intravenous midazolam premedication. Children who developed a paradoxical reaction were randomly divided into three equal groups to receive: (i) extra midazolam, (ii) ketamine, or (iii) placebo as the test drug for treatment of paradoxical reaction. Ease of rapid tranquillization and need for a rescue tranquillizer (i.e. ketamine; irrespective of patient group) were compared among the three groups.

RESULTS

Twenty-four (3.4%) children developed paradoxical reaction after midazolam premedication. Those who received ketamine as the test drug responded rapidly to ketamine. But the responses of the other two groups to their test drug were poor and the majority of them required ketamine as rescue tranquillizer (six in midazolam, seven in placebo, but no patient in the ketamine group; P < 0.05).

CONCLUSIONS

The results of this study demonstrate that ketamine is an effective drug for the treatment of paradoxical reaction following intravenous midazolam premedication. The exact mechanisms of these reactions and how it is aborted by ketamine are not clear.

Safety and effectiveness of ketamine as a sedative agent for pediatric GI endoscopy

BACKGROUND

The ideal sedation for children undergoing GI endoscopy remains elusive. After ketamine was introduced as a sedative agent in our GI procedure suite, improved sedation and reduced complications were observed. The aim of this study was to assess the safety and effectiveness of ketamine as a sedative agent for GI endoscopy in pediatric patients.

METHODS

A retrospective cohort study of 402 procedures (EGD, colonoscopy) was performed. Sedation-related complications were defined as hypoxia (oxygen saturation <95% by pulse oximetry), agitation, emergence reactions, stridor, laryngospasm, nausea, vomiting, aspiration, and muscle twitching, or any combination thereof. Sedation groups were defined as the following: Group I, midazolam and meperidine (n=192); Group II, midazolam, meperidine, and ketamine (n=82); and Group III, midazolam and ketamine (n=128).

RESULTS

Group 1 (midazolam and meperidine) had the highest frequency of complications, most commonly hypoxia. Group 3 (midazolam and ketamine) had the lowest rate of complications (p=0.001) and the highest rate of adequate sedation, although the difference was not significant (p=0.07).

CONCLUSIONS

The combination of midazolam and ketamine appears to provide safe and effective sedation for pediatric patients undergoing endoscopy.

Unsedated upper endoscopy in children

BACKGROUND

EGD is essential to the investigation and treatment of GI disorders in children. Although safe, EGD has the potential for complications, in particular cardiopulmonary abnormalities associated with intravenous sedation. EGD is often performed in adults without sedation. Unsedated EGD is occasionally performed in children but has not been subjected to study. This study assessed the safety, efficacy, and feasibility of unsedated EGD in children.

METHODS

Selected, highly motivated children requiring EGD were offered the choice of sedation or no sedation for the procedure. Children recorded scores for pain (face scale) and anxiety (vertical visual analogue scale) before and after EGD. In addition, the times required to prepare the patient, perform the EGD, and recover the patient were recorded.

RESULTS

There was no difference in age, gender, or pre-EGD pain scores between children selecting sedation or no sedation. However, children selecting sedation had significantly higher pre-EGD anxiety scores than those who chose no sedation. Successful completion of EGD was similar for sedated (96.3%) and unsedated (95.2%) children. Post-EGD scores for anxiety were significantly decreased in those receiving sedation and unchanged in children who received no sedation. There was no significant change in post-EGD pain score in either group. Nearly 80% of children undergoing unsedated EGD would elect to forego sedation if EGD was needed again. Total procedure time was significantly longer in sedated versus unsedated children, reflecting longer preparation and recovery.

CONCLUSIONS

Unsedated EGD can be performed safely and successfully in children with good patient tolerance. There was a significant decrease in total procedure time for children who have unsedated EGD. Unsedated EGD should be considered a viable option for motivated children.

Children's knowledge, anticipatory anxiety, procedural distress, and recall of esophagogastroduodenoscopy

BACKGROUND

This study evaluates the relations among children's knowledge of esophagogastroduodenoscopy (EGD) and anticipatory anxiety, procedural distress, and the nature of postprocedural recall and evaluations.

METHODS

One hundred patients, aged 8 to 17 years, completed self-report measures of knowledge and anxiety before EGD. Parents completed a self-report measure assessing how they prepared their children. Nurses and trained observers completed observational ratings of distress. Children's recall and evaluation of the procedure were assessed by self-report 1 hour after the procedure and by telephone that evening.

RESULTS

Most children knew about the major components of EGD. Children with greater knowledge experienced less distress and reported that they would be less anxious and upset when undergoing future EGDs. Children with greater anticipatory anxiety exhibited more procedural distress. Children's distress varied by the phase of the procedure. Children who were more distressed during intravenous line insertion experienced greater distress during esophageal intubation and the endoscopic examination. Approximately 20% of patients reported at least some memory of the procedure even at the end of the day. Children with greater recall reported greater aversion and a more negative attitude toward future EGDs.

CONCLUSIONS

This study provides information about children's distress during EGD and the effects of conscious sedation on patients' memories and attitudes toward future procedures. The study indicates that preparation before EGD may reduce patient distress.

Ketamine sedation for pediatric gastroenterology procedures

BACKGROUND

Although the dissociative sedative ketamine is used commonly for pediatric procedural sedation in other settings, the safety of this agent in pediatric gastroenterology is not well-studied. A 5-year experience with ketamine sedation for pediatric gastroenterology procedures was reviewed to document the safety profile of this agent and to identify predictors of laryngospasm during esophagogastroduodenoscopy (EGD).

METHODS

The study was a retrospective consecutive case series of children receiving ketamine administered by pediatric gastroenterologists skilled in basic airway management to facilitate pediatric gastrointestinal procedures during a 5-year period. Patient's records were reviewed to determine indication, dosage, adverse effects, drugs, inadequate sedation, and recovery time for each sedation. A multiple logistic regression analysis was performed to identify predictors of laryngospasm during EGD. Outcome measures were descriptive features of sedation, including adverse effects and predictors of laryngospasm during EGD.

RESULTS

During the study period pediatric gastroenterologists administered ketamine 636 times, primarily for EGD (86%) and primarily by the intravenous route (98%). The median loading dose and total dose were 1.00 mg/kg and 1.34 mg/kg, respectively. Inadequate sedation was noted in seven (1.1%) procedures. Adverse effects included transient laryngospasm (8.2%), emesis (4.1%), recovery agitation (2.4%), partial airway obstruction (1.3%), apnea and respiratory depression (0.5%), and excessive salivation (0.3%). There were no adverse outcomes attributable to ketamine. Nearly half (46%) the subjects had severe underlying illness (American Society of Anesthesiologists (ASA] class > or =3). All instances of laryngospasm occurred during EGD (9.5% incidence), and the only independent predictor of laryngospasm in this sample was decreasing age. The incidence of laryngospasm was 13.9% in preschool-aged (< or =6 years) children and was 3.6% in school-aged (>6 years) children (difference 10.3%, 95% confidence intervals 5.5-14.9%). No dose relationship was noted with laryngospasm, and the risk did not increase with underlying illness.

CONCLUSION

Pediatric gastroenterologists skilled in ketamine administration and basic airway management can effectively administer this drug to facilitate gastrointestinal procedures. Transient laryngospasm occurred in 9.5% of children receiving ketamine for EGD, and its incidence was greater in preschool than in school-aged children.

Nitrous oxide sedation in pediatric patients undergoing gastrointestinal endoscopy

BACKGROUND

The ideal medication to administer to children before gastrointestinal endoscopy procedures has yet to be found. The efficacy of using inhaled nitrous oxide during endoscopy in children was assessed in a pilot study.

METHODS

Patients aged 5 to 17 years, referred to our hospital for diagnostic upper gastrointestinal endoscopy or rectosigmoidoscopy procedures, were eligible for enrollment in this study. All received 50% nitrous oxide in oxygen (Entonox; AGA, Rueil-Malmaison, France) before endoscopy and some of them again during endoscopy. The pediatric endoscopist and the nurse performing the procedure were separately asked to rate cooperation, emotional state, drowsiness and overall efficacy of sedation. Oxygen saturation and adverse effects were recorded throughout the procedure. After endoscopy, children scored their degree of pain during the procedures on a visual analog scale (0, no pain; 100, agony) and on a body outline (projective method). Any adverse effects were noted.

RESULTS

Thirty-seven patients were enrolled in the study. Thirty patients underwent diagnostic upper gastrointestinal endoscopy and seven diagnostic rectosigmoidoscopy. The median time from administration of nitrous oxide until insertion of the endoscope was 5 minutes (range, 3-8 minutes). Good or excellent efficacy of the sedation was noted in 92% of children by the endoscopist and in 89% by the nurses. Good or excellent cooperation was noted in 92% of the children by the endoscopist and in 78% by the nurses. The children's pain score on the visual analog scale ranged from 5 to 100 (median, 20) for upper gastrointestinal endoscopy and from 0 to 30 (median, 0) for rectosigmoidoscopy. The time of discharge after endoscopy, defined as the time elapsed between the end of the endoscopy and discharge from the endoscopy suite, varied from 1 to 7 minutes (median, 1.5 minutes).

CONCLUSION

Entonox provides rapid and effective analgesia without heavy sedation, leads to adequate relaxation and cooperation, and facilitates quick and efficient endoscopy. The effect of Entonox was of short duration, allowing the children to leave the endoscopy unit without need for a long recovery period. The adverse effects of Entonox appeared to be minor, and their duration was always brief. Nitrous oxide-oxygen inhalation may provide a valuable alternative to conventional sedation regimens during gastrointestinal endoscopy in children, but randomized and prospective studies comparing nitrous oxide sedation and conventional sedation regimens are necessary.

Sedation for pediatric procedures, using ketamine and midazolam, in a primarily adult intensive care unit: a retrospective evaluation

OBJECTIVE

To evaluate the effectiveness and safety of pediatric procedures performed by adult critical care practitioners, using the combination of ketamine and midazolam for anesthesia and sedation.

DESIGN

A retrospective case series.

SETTING

The intensive care unit (ICU) of a 325-bed tertiary research hospital.

PATIENTS

Individuals from 1 to 18 yrs of age who had intravenous midazolam sedation and ketamine anesthesia administered while undergoing lumbar puncture, bone biopsy, central venous catheter placement, liver biopsy, thoracentesis, or bone marrow aspirate/biopsy.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A retrospective chart review was performed. The dosages of medications used were tabulated, and milligram per kilogram dosages were calculated. The procedures performed, their durations, and any complications of the anesthesia and sedation were noted. These complications included: oxygen desaturations <90%, vital sign alterations requiring intervention, rashes, subjective complaints of dizziness by the patient, and emergence reactions to ketamine. A total of 127 pediatric patients were admitted to the ICU sedation area for a total of 295 procedures. All patients received ketamine and midazolam intravenously in divided doses and titrated to effect. A total of nine complications were observed. These complications included oxygen desaturation <90% (n = 1), vital sign alterations requiring treatment (n = 3), rash (n = 2), dizziness (n = 1), wheezing (n = 1), and emergence reaction (n = 1). No patient required admission to the ICU because of a complication. There were no episodes of bradycardia or other cardiopulmonary compromise.

CONCLUSIONS

Pediatric anesthesia and sedation, using ketamine and midazolam, can be performed in a designated monitored setting, outside of the operating room, by experienced personnel, including nonpediatricians. This therapeutic combination allows painful procedures to be performed with less anxiety and discomfort. In experienced hands, a limited number of side effects occur.

Clinical pharmacology of midazolam in infants and children

Midazolam is a parenteral benzodiazepine with sedative, amnesic, anxiolytic, muscle relaxant and anticonvulsant properties. The drug exerts its clinical effect by binding to a receptor complex which facilitates the action of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Midazolam has a faster onset and shorter duration of action than other benzodiazepines such as diazepam and lorazepam. The most serious adverse events associated with midazolam in children include hypoventilation, decreased oxygen saturation, apnoea and hypotension. It is water soluble in the commercially prepared formulation but becomes lipid soluble at physiological pH and can then cross the blood brain barrier. It is metabolised in the liver by the cytochrome P450 system, and its chief metabolite is 1-hydroxymethyl midazolam. The latter is conjugated to the glucuronide form, and it has only minimal biological activity. Midazolam is excreted primarily by the kidney. Its half-life in children over 12 months is reported to be 0.8 to 1.8 hours, with a clearance of 4.7 to 19.7 ml/min/kg. Doses given to children must be calculated on a mg/kg basis. For children 6 months to 5 years of age the initial dose is 0.05 to 0.1 mg/kg. A total dose up to 0.6 mg/kg titrated slowly may be necessary to achieve the desired endpoint. For children 6 to 12 years of age the initial dose is 0.025 to 0.05 mg/kg with a total dose up to 0.4 mg/kg to achieve the desired end-point.

Paradoxical reactions in children associated with midazolam use during endoscopy

All 2,617 children who received midazolam and meperidine for a variety of endoscopic procedures were monitored for the development of adverse behavioral problems. Thirty-six (1.4%) of the children (ages 1-17 years) experienced a paradoxical behavioral reaction, which consisted of inconsolable crying, combativeness, disorientation, dysphoria, tachycardia, agitation, and restlessness. The reaction occurred at a mean of 17 minutes after the administration of midazolam. Following treatment with flumazenil, the reaction dissipated within a mean of 14 minutes. Three of the 36 patients underwent additional endoscopic procedures utilizing only meperidine. No similar reaction was observed in these patients. Awareness of the reaction and prompt administration of flumazenil decreased the duration of the reaction.