The Effect of Dexmedetomidine on Emergence Agitation or Delirium in Children After Anesthesia-A Systematic Review and Meta-Analysis of Clinical Studies

The effect of magnesium sulfate on emergence agitation in surgical adult patients undergoing general anesthesia: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

Investigating the effect of magnesium sulfate (MS) on emergence agitation (EA) in adult surgical patients following general anesthesia (GA).

DESIGN

Systematic literature review and meta-analysis (PROSPERO number: CRD42023461988).

SETTING

Review of published literature.

PATIENTS

Adults undergoing GA.

INTERVENTIONS

Intravenous administration of MS.

MEASUREMENTS

We searched PubMed/MEDLINE, EMBASE, the Cochrane Library, Scopus, and Web of Science for publications until September 14, 2023. The primary outcome was the incidence of EA, while the secondary outcomes included the impact of MS on postoperative agitation score (PAS), emergence variables and adverse events. Relative risk (RR) with 95% confidence interval (CI) measured dichotomous outcome, while standardized mean difference (SMD) or mean difference (MD) with 95% CI measured continuous outcomes.

MAIN RESULTS

Meta-analysis of five randomized controlled trials (RCTs) indicated that MS was associated with a lower incidence of EA at various time points (0 min: RR = 0.62, 95% CI [0.41, 0.95]; p = 0.183, I2 = 43.6%; 5 min: RR = 0.29, 95% CI [0.16, 0.52]; p = 0.211, I2 = 36%; 10 min: RR = 0.14, 95% CI [0.06, 0.32]; p = 0.449, I2 = 0%; 15 min: RR = 0.11, 95% CI [0.02, 0.55]; p = 0.265, I2 = 19.5%; 30 min: RR = 0.05, 95% CI [0.00, 0.91]; the postoperative period: RR = 0.21, 95% CI [0.09, 0.49]; p = 0.724, I2 = 0%;). Additionally, MS was associated with a reduced PAS at various time points except for 0 min. However, no significant differences were observed in extubation time, the length of stay in the post-anesthesia care unit, postoperative nausea and vomiting or total complications.

CONCLUSIONS

Limited available evidence suggests that MS was associated with a lower incidence of EA. Nevertheless, further high-quality studies are warranted to strengthen and validate the effect of MS in preventing EA in adult surgical patients.

A prospective, observational validation of HRAD±, a novel pediatric affect and cooperation scale

STUDY OBJECTIVE

HRAD± was developed to quickly assess pediatric perioperative affect and cooperation. HRAD± represents: Happy, Relaxed, Anxious, Distressed, with a yes/no answer to cooperativity. The primary aim of this study was to investigate the clinical utility of HRAD± as an affect and cooperation assessment tool for inhalational mask induction. Secondary aims examined inter-rater reliability (IRR) of HRAD± and predictive validity of induction HRAD± with emergence delirium.

DESIGN

This was a prospective observational investigation.

SETTING

We conducted this investigation at Lucile Packard Children's Hospital Stanford, an academic, quaternary care children's hospital in Northern California.

PATIENTS

A total of 197 patients were included in this investigation. Children 1-14 years of age, who underwent daytime procedures with inhalational induction of anesthesia and American Society of Anesthesiologists physical status I-III were eligible.

INTERVENTIONS

During mask induction, two trained research assistants (RAs) independently scored the patient's affect and cooperation. After extubation, the same investigators observed the patient's emergence.

MEASUREMENTS

RAs scored each mask induction using the following scales: HRAD±, modified Yale Preoperative Anxiety Scale (mYPAS), Observation Scale of Behavioral Distress (OSBD), and Induction Compliance Checklist (ICC). Correlations were calculated to HRAD±. IRR of HRAD± between the RAs as well as predictive validity of HRAD± to Pediatric Anesthesia Emergence Delirium (PAED), Watcha and Cravero scales were calculated.

MAIN RESULTS

HRAD± scores strongly correlated with mYPAS (r = 0.840, p < 0.0001) with moderate correlation to OSBD (r = 0.685, p < 0.0001) and ICC (-0.663, p < 0.0001). IRR was moderate for the affect and cooperation portion of the HRAD± scale, respectively (κ = 0.595 [p < 0.0001], κ = 0.478 [p < 0.0001]). A weak correlation was observed with PAED (r = 0.134 [p = 0.0597]) vs HRAD±. No correlations were observed between Watcha (r = 0.013 [p = 0.8559]) and Cravero and HRAD± scales (r = 0.002 [p = 0.9767]).

CONCLUSIONS

HRAD± is a clinically useful and simple scale for evaluating pediatric affect and cooperation during inhalational mask induction. Results demonstrate correlation with commonly utilized research assessment scales.

Effect of recorded mother's voice on emergence delirium in pediatric patients: a systematic review with meta-analysis

OBJECTIVE

Emergence delirium is a common complication in children. Recorded mother's voice, as a non-pharmacological measure, is increasingly used to prevent the emergence of delirium in pediatric patients, but sufficient evidence is still needed to prove its efficacy.

METHODS

Embase, PubMed, Cochrane Library, Web of Science, CINAHL, and Sinomed databases were searched for randomized controlled trials exploring the efficacy of recorded mother's voice in preventing the emergence of delirium in pediatric patients undergoing general anesthesia. The original data were pooled for the meta-analysis with Review Manager 5.4.1. This study was conducted based on the Cochrane Review Methods.

RESULTS

Eight studies with 724 children were included in the analysis. Recorded mother's voice reduced the incidence of emergence delirium when compared with either no voice (RR: 0.45; [95 % CI, 0.34 - 0.61]; p < 0.01; I2 = 7 %) or stranger's voice (RR: 0.51; [95 % CI, 0.28 - 0.91]; p = 0.02; I2 = 38 %) without increasing other untoward reactions. In addition, it shortened the post-anesthesia care unit stay time when compared with no voice (MD = -5.64; [95 % CI, -8.43 to -2.58]; p < 0.01, I2 = 0 %), but not stranger's voice (MD = -1.23; [95 % CI, -3.08 to 0.63]; p = 0.19, I2 = 0 %). It also shortened the extubation time and reduced the incidence of postoperative rescue analgesia.

CONCLUSION

The current analysis indicated that recorded mother's voices could reduce the incidence of emergency delirium, shorten post-anesthesia care unit stay time and extubation time, and decrease the incidence of postoperative rescue analgesia in children.

Oral Dexmedetomidine Achieves Superior Effects in Mitigating Emergence Agitation and Demonstrates Comparable Sedative Effects to Oral Midazolam for Pediatric Premedication: A Systematic Review and Meta-Analysis of Randomized Controlled Studies

Background: Oral midazolam is the most commonly used sedative premedication agent in pediatric patients. While effective, oral midazolam cannot reduce the incidence of emergence agitation. Oral dexmedetomidine may be effective in providing satisfactory sedation and reduce the incidence of emergence agitation, although the results of different randomized controlled trials are conflicting. Methods: This study enrolled randomized controlled trials (RCTs) examining premedication with oral dexmedetomidine versus oral midazolam in pediatric patients undergoing general anesthesia. PubMed, the Cochrane Library, Embase, and the Web of Science database were searched from their inception until June 2023. The outcomes were the incidence of satisfactory preoperative sedation, satisfactory sedation during separation from parents, satisfactory sedation during anesthesia induction using an anesthesia mask, and the incidence of emergence agitation. Results: A total of 9 RCTs comprising 885 patients were analyzed. Our data revealed comparable effects of dexmedetomidine and midazolam with respect to satisfactory preoperative sedation and a satisfactory incidence of sedation during parental separation and mask acceptance before anesthesia induction. Notably, our data revealed that the rate of emergence agitation was significantly lower in pediatric patients receiving dexmedetomidine (n = 162) than in those receiving midazolam (n = 159) (odds ratio = 0.16; 95% confidence interval: 0.06 to 0.44; p < 0.001; I2 = 35%). Conclusions: Data from this meta-analysis revealed comparable effects for premedication with oral dexmedetomidine or oral midazolam with respect to satisfactory sedation; furthermore, premedication with oral dexmedetomidine more effectively mitigated emergence agitation in pediatric patients receiving general anesthesia compared with oral midazolam.

Transversus abdominis plane block versus caudal block with bupivacaine and dexmedetomidine for unilateral inguinal hernia repair in pediatric patients: a randomized clinical trial

BACKGROUND

This study compared the transversus abdominis plane (TAP) block with bupivacaine and dexmedetomidine to the same mixture in the caudal block in delivering postoperative analgesia in children after unilateral inguinal hernia surgery.

METHODS

The current study included 80 children aged two to eight years who were scheduled for unilateral inguinal hernia surgery under general anesthesia. A caudal block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) or a TAP block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) was given to each participant at random. The time it took to request analgesia for the first time, the postoperative pain score, total analgesic use, sedation, family satisfaction, and side effects were all measured. The primary outcome was time to first analgesic request.

RESULTS

The caudal block group had a considerably shorter time to first analgesic request than the TAP block group. The caudal block group received more rescue analgesia doses within 24 hours than the TAP block group. The mean total dose of intravenous paracetamol within the first 24 hours postoperatively was greater in the caudal block group. The caudal block group had much higher family satisfaction.

CONCLUSIONS

The TAP block and caudal block provide good postoperative analgesia in children undergoing unilateral inguinal hernia repair. Adding dexmedetomidine to the TAP block was superior to the caudal block in terms of extending the length of the initial analgesic request, lowering analgesic requirement, and lowering pain scores without causing substantial adverse effects.

Anesthesia outcomes in lysosomal disorders: CLN3 and GM1 gangliosidosis

Natural history studies of pediatric rare neurometabolic diseases are important to understand disease pathophysiology and to inform clinical trial outcome measures. Some data collections require sedation given participants' age and neurocognitive impairment. To evaluate the safety of sedation for research procedures, we reviewed medical records between April 2017 and October 2019 from a natural history study for CLN3 (NCT03307304) and one for GM1 gangliosidosis (NCT00029965). Twenty-two CLN3 individuals underwent 28 anesthetic events (age median 11.0, IQR 8.4-15.3 years). Fifteen GM1 individuals had 19 anesthetic events (9.8, 7.1-14.7). All participants had the American Society of Anesthesiology classification of II (8/47) or III (39/47). Mean sedation durations were 186 (SD = 54; CLN3) and 291 (SD = 33; GM1) min. Individuals with GM1 (6/19, 31%) were more frequently prospectively intubated for sedation (CLN3 3/28, 11%). Minor adverse events associated with sedation occurred in 8/28 (28%, CLN3) and 6/19 (32%, GM1) individuals, frequencies within previously reported ranges. No major adverse clinical outcomes occurred in 47 anesthetic events in pediatric participants with either CLN3 or GM1 gangliosidosis undergoing research procedures. Sedation of pediatric individuals with rare neurometabolic diseases for research procedures is safe and allows for the collection of data integral to furthering their understanding and treatment.

Comparative Study of the Effect of Two Different Doses of Dexmedetomidine to Prevent Emergence Agitation in Tonsillectomy in Children Aged 2 to 12 Years Old

Background

Emergence agitation (EA) is one of the complications following anesthesia in pediatric surgery. Various drugs are used to prevent this complication, and one of them is dexmedetomidine. Choosing the right dose of this drug for the best efficiency is an important issue due to this complication.The main purpose of this study is to evaluate the prophylactic effect of intravenous dexmedetomidine in different doses in preventing EA after tonsillectomy in children.

Materials and Methods

Our study was a double-blind clinical trial performed on 75 children ASAI, II candidates for tonsillectomy. Patients were divided into three groups. The group 1 received a dose of 0.6 μg/kg per hour and group 2 received a dose of 0.3 μg/kg per hour and group 3 was the control group. Then vital signs and observational pain score (OPS) and pediatric anesthesia emergence delirium (PAEDS) criteria were measured in patients. The collected data were analyzed by using SPSS software version 23 and non-parametric tests such as Friedman, Mann-Whitney.

Results

According to the data analysis, mean blood pressure, mean heart rate, OPS and PAEDS score in group 1 were lower than other groups. Also, the average time of staying in recovery and extubation in group 1 was less than other groups.

Conclusion

A dose of 0.6 μg/kg dexmedetomidine has a better effect on reducing EA (emergence agitation) after pediatric tonsillectomy.

A Perioperative Intervention to Prevent and Treat Emergence Delirium at a Veterans Affairs Medical Center

Emergence delirium (ED) is a temporary condition associated with a patient awakening from an anesthetic and/or adjunct agent (e.g., sedatives and analgesics). During the condition, patients risk harming themselves or staff by engaging in dangerous behavior, which may include thrashing, kicking, punching, and attempting to exit the bed/table. A multidisciplinary team at Veterans Affairs Pittsburgh Healthcare System (VAPHS) developed and implemented a multicomponent intervention to reduce the severity and occurrence of ED. The intervention consists of a training component and 21 clinical components. The 21 clinical components are implemented on a patient-by-patient basis and include routine screening for risk factors, enhanced communication among staff, adjusting the environment, following a specific medication strategy, and application of manual restraint (hands-on). The authors provide 15 online Supplemental Materials (S1–S15) to promote replication of the intervention. To our knowledge, this is the first manuscript that describes this type of multicomponent intervention in sufficient detail to allow others to replicate it. Following implementation of the intervention at VAPHS, perioperative staff reported that they observed a substantial reduction in the occurrence and severity of ED, ED-related patient and staff injuries, and ED-related loss of intravenous access and airway patency. Despite staff’s reported success of the intervention, rigorous research is needed to evaluate the efficacy of the intervention.

Online Supplement to “A Perioperative Intervention to Prevent and Treat Emergence Delirium at a Veteran Affairs Medical Center”

This supplementary material was provided by the authors to give readers additional information and resources to replicate their work.

What Is the Role of Dexmedetomidine in Modern Anesthesia and Critical Care?

Dexmedetomidine's unique sedative properties have led to its widespread use. Dexmedetomidine has a beneficial pharmacologic profile including analgesic sparing effects, anxiolysis, sympatholysis, organ-protective effects against ischemic and hypoxic injury, and sedation which parallels natural sleep. An understanding of predictable side effects, effects of age-related physiologic changes, and pharmacokinetic and pharmacodynamic effects of dexmedetomidine is crucial to maximize its safe administration in adults and children. This review focuses on the growing body of literature examining advances in applications of dexmedetomidine in children and adults.

Incidence of Emergence Delirium in the Pediatric PACU: Prospective Observational Trial

Emergence delirium (ED) is a postoperative complication in pediatric anesthesia characterized by perception and psychomotor disorder and has a negative impact on morbidity in the form of maladaptive behavior, which can last weeks after anesthesia. Patients with developed ED present with psychomotor anxiety, agitation, and are at higher risk of unintentional extraction of an intravenous cannula, self-harm and nausea and vomiting. The described incidence of ED varies between 25−80%, with a higher prevalence among children younger than 6 years of age. We aimed to determine the incidence of ED in pediatric patients (>1 month) after general anesthesia in the post-anesthesia care unit (PACU), using Paediatric Anaesthesia Emergence Delirium (PAED) score, Watcha score and Richmond agitation and sedation scale (RASS). The incidence of ED was the highest in the PAED score with cutoff ≥10 points (89.0%, n = 1088). When using PAED score >12 points, ED incidence was 19.3% (n = 236). The lowest incidence was described by Watcha and RASS scores, 18.8% (n = 230) vs. 18.1% (n = 221), respectively. The threshold for PAED ≥10 points seems to give false-positive results, whereas the threshold >12 points is more accurate. RASS scale, although intended primarily for estimation of the depth of sedation, seems to have a good predictive value for ED.

Historical and Modern Evidence for the Role of Reward Circuitry in Emergence

Increasing evidence supports a role for brain reward circuitry in modulating arousal along with emergence from anesthesia. Emergence remains an important frontier for investigation, since no drug exists in clinical practice to initiate rapid and smooth emergence. This review discusses clinical and preclinical evidence indicating a role for two brain regions classically considered integral components of the mesolimbic brain reward circuitry, the ventral tegmental area and the nucleus accumbens, in emergence from propofol and volatile anesthesia. Then there is a description of modern systems neuroscience approaches to neural circuit investigations that will help span the large gap between preclinical and clinical investigation with the shared aim of developing therapies to promote rapid emergence without agitation or delirium. This article proposes that neuroscientists include models of whole-brain network activity in future studies to inform the translational value of preclinical investigations and foster productive dialogues with clinician anesthesiologists.

Best Evidence-Based Dosing Recommendations for Dexmedetomidine for Premedication and Procedural Sedation in Pediatrics: Outcome of a Risk-Benefit Analysis By the Dutch Pediatric Formulary

BACKGROUND

Dexmedetomidine is currently off-label for use in pediatric clinical care worldwide. Nevertheless, it is frequently prescribed to pediatric patients as premedication prior to induction of anesthesia or for procedural sedation. There is ample literature on the pharmacokinetics, efficacy and safety of dexmedetomidine in this vulnerable patient population, but there is a general lack of consensus on dosing. In this project, we aimed to use the standardized workflow of the Dutch Pediatric Formulary to establish best evidence-based pediatric dosing guidelines for dexmedetomidine as premedication and for procedural sedation.

METHOD

The available literature on dexmedetomidine in pediatrics was reviewed in order to address the following three questions: (1) What is the right dose? (2) What is known about efficacy? (3) What is known about safety? Relevant literature was compiled into a risk-benefit analysis document. A team of clinical experts critically appraised the analysis and the proposed dosing recommendations.

RESULTS

Dexmedetomidine is most commonly administered via the intravenous or intranasal route. Clearance is age dependent, warranting higher doses in infants to reach similar exposure as in adults. Dexmedetomidine use results in satisfactory sedation at parent separation, adequate sedation and a favorable recovery profile. The safety profile is good and comparable to adults, with dose-related hemodynamic effects.

CONCLUSION

Following the structured approach of the Dutch Pediatric Formulary, best evidence-based dosing recommendations were proposed for dexmedetomidine, used as premedication prior to induction of anesthesia (intranasal dose) and for procedural sedation (intranasal and intravenous dose) in pediatric patients.

Comparison of nebulized dexmedetomidine and ketamine for premedication in pediatric patients undergoing hernia repair surgery: a randomized comparative trial

Background

Allaying anxiety and providing calm children in the operating room is a challenging task for anesthesiologists. This study was designed to compare the use of nebulized dexmedetomidine and ketamine for premedication in pediatric patients under general anesthesia.

Methods

Seventy patients, aged 2 to 8 years of both sexes, with American Society of Anesthesiologists physical status I/II scheduled for hernia repair surgery under general anesthesia, were randomized to two equal groups using a computer-generated random number table. Patients in group D received dexmedetomidine (2 µg/kg), and patients in group K received ketamine (2 mg/kg) by a jet nebulizer before the induction of anesthesia. The study's primary objective was comparing the level of sedation, which was achieved at 30 min after a study drug administration using the Ramsay sedation scale, between the two groups. The secondary objectives were the two-group comparison of parental separation anxiety scale, acceptance of the mask, hemodynamic variables, recovery time, incidence of emergence agitation, and adverse events.

Results

The median Ramsay sedation scale at 30 min was 3 (1–4) in group D and 3 (1–3) in group K (P = 0.002). Patients in group D had a more acceptable parental separation anxiety scale (P = 0.001) and a satisfactory mask acceptance scale (P = 0.042).

Conclusions

Nebulized dexmedetomidine (2 µg/kg) provided better sedation along with smooth parental separation and satisfactory mask acceptance during induction of anesthesia with a similar emergence agitation profile and adverse reactions compared to nebulized ketamine in pediatric patients.

Single bolus dexmedetomidine versus propofol for treatment of pediatric emergence delirium following general anesthesia

BACKGROUND

Pediatric emergence delirium is a psychomotor disorder occurring in the early postanesthetic stage. There is no clear consensus regarding its treatment; however, dexmedetomidine and propofol have both been shown to be effective.

AIM

In this single-center, randomized, double-blind prospective study, we compared the efficacy of dexmedetomidine against that of propofol in the treatment of established emergence delirium in pediatric patients undergoing general anesthesia.

METHODS

Patients aged 1-14 years, with ASA I or II and severe emergence delirium (Pediatric Anesthesia Emergence Delirium score of ≥15) during the postoperative period following general anesthesia, were randomized to receive intravenous bolus injection of 0.5 μg.kg^-1 dexmedetomidine or 1 mg.kg^-1 propofol. The primary outcome was the pediatric anesthesia emergence delirium (PAED) score after treatment, and the secondary outcome was the recovery time in the postanesthetic care unit.

RESULTS

Of the 53 patients who participated in the study, 26 (49%) were treated with dexmedetomidine and 27 (51%) with propofol. In the dexmedetomidine group, a single-dose intervention was effective for all patients (100%); whereas in the propofol group, 19 patients (70.4%) had PAED score of <12 after the first dose (p = .004; relative risk [95% confidence interval] = 0.1422 [0.113-1.815]). No significant difference in recovery time (median [IQR (range)]) was observed between the dexmedetomidine (20[14-30(10-45)]) and propofol groups (25 [20-40 (10-50)]; p = .056; 95% confidence interval = 0.113-1.815).

CONCLUSIONS

A single bolus of 0.5 μg.kg^-1 of dexmedetomidine was more effective than a single bolus of 1 mg.kg^-1 of propofol in treating emergence delirium during the early postanesthetic stage.

Risk factors for emergence agitation in adults after general anesthesia: A systematic review and meta-analysis

BACKGROUND

Emergence agitation (EA) is an adverse post-operative complication that increases the risk for injury, self-extubation, hemorrhages, and prolonged hospitalization. This meta-analysis aims to define the risk factors for adult EA after general anesthesia and provide recommendations for clinical practice.

METHODS

Embase, PubMed, Medline, and the Cochrane Library databases were comprehensive retrieved. Observational studies that reported the risk factors for adult EA were enrolled. Review Manager 5.4 was used to analyze the extracted data.

RESULTS

Eighteen observational studies involving 16, 678 adult patients were enrolled in this study. Eighteen pre-operative and nineteen intraoperative factors with unadjusted data, and five pre-operative and five intraoperative factors with adjusted data were meta-analyzed separately. Among them, seven factors (age, male, smoking, history of substance misuse, inhalational anesthesia, urinary catheter, complain of pain, or need analgesic drug use in post-anesthetic care unit) were the risk factors no matter meta-analyzed by unadjusted data or adjusted data. Intraoperative use of benzodiazepines was the risk factor when meta-analyzed by adjusted data, but not unadjusted data. Moreover, age and inhalational anesthesia were not the risk factors when omitted one study for sensitivity analysis, and history of substance misuse could not do sensitivity analysis.

CONCLUSION

Based on this meta-analysis, male, smoking, urinary catheter, and post-operative pain are the risk factors, while age, inhalational anesthesia, history of substance misuse, and intraoperative use of benzodiazepines are the possible risk factors for adult EA.

EDITORIAL COMMENT

This systematic review and meta-analysis identify risk factors associated with the occurrence of agitation during emergence from general anesthesia. As might be expected, the strongest factors are generally things which are irritating or painful for patients, but cannot necessarily be avoided.

Effect of different administration and dosage of dexmedetomidine in the reduction of emergence agitation in children: a meta-analysis of randomized controlled trials with sequential trial analysis

BACKGROUND

Beneficial effects of dexmedetomidine (DEX) against emergence agitation (EA) in children remain controversial. We performed a more comprehensive meta-analysis to evaluate the protective effect of different administration routes, timing, patterns, and doses of DEX on EA in children.

METHODS

The randomized controlled trials about DEX preventing EA in children were searched in PubMed, Cochrane Library, Embase, and Web of Sciences up to October 7, 2020. The traditional meta-analysis and subgroup analysis were performed to study the influence of DEX on EA in children. The sequential trial analysis (TSA) further analyzed the pooled results to evaluate meta-analyses' robustness. Grading of recommendation, assessment, development, and evaluation (GRADE) was used to assess evidence quality.

RESULTS

Sixty-seven studies with 5,688 pediatric patients were included. DEX significantly decreased EA in children compared to placebo [RR 0.29, 95% confidence intervals (CI): 0.25-0.34] and midazolam (RR 0.34, 95% CI: 0.25-0.45), with firm evidence from TSA. Notably, using DEX significantly reduced severe EA incidence (RR 0.23, 95% CI: 0.16-0.32), with firm evidence by TSA and high quality of GRADE. Pre-specified subgroup analyses revealed firm and high-quality evidence for a reduction of EA, only if the perineural route administers DEX (RR 0.24, 95% CI: 0.14-0.41), as premedication (RR 0.27, 95% CI: 0.20-0.36), as continuous dosage (RR 0.25, 95% CI: 0.18-0.33), at high dose (RR 0.24, 95% CI: 0.18-0.31). The pooled results also showed that DEX reduced the incidence of PONV compared to placebo (RR 0.43, 95% CI: 0.33-0.55). Evidence for DEX's influence on other secondary outcomes (emergence time, time in PACU, rescue analgesia, hypotension, and bradycardia) is insufficient to draw any conclusion.

CONCLUSIONS

Our findings confirm the beneficial effects of DEX on EA, severe EA, and PONV in children. There was firm and high-quality evidence for the efficacy of DEX in preventing EA in children when perineural routes administered DEX, as premedication, as continuous dosage, and at a high dose. The best dose, route, patterns, and timing of DEX and influence on other outcomes call for further studies.

A Randomized Controlled Study of Caudal Dexmedetomidine for the Prevention of Postoperative Agitation in Children Undergoing Urethroplasty

Background: Postoperative agitation is a common complication in children undergoing general anesthesia. This study aimed to investigate the effect of caudal dexmedetomidine for the prevention of postoperative agitation in children undergoing urethroplasty. Materials and Methods: Eighty children were prospectively recruited to this study and randomized to two groups (40 cases in each group), specifically, a dexmedetomidine group (group D) who received 0.2% ropivacaine + 0.5 μg/kg dexmedetomidine for caudal block, and a control group who received 0.2% ropivacaine alone. The time to wake up, the time to discharge from the postanesthesia care unit (PACU), the duration of the caudal block, and the Ramsay sedation scale (RSS) were evaluated in the patients. Adverse events such as postoperative agitation, respiratory depression, bradycardia, hypotension, excessive sedation, nausea, and vomiting were also recorded during the first postoperative 24 h. Results: The incidence of postoperative agitation was lower in group D compared with patients in the control group (2.5 vs. 22.5%, p = 0.007). The time to wake up and the time to discharge from PACU were longer in group D than in the control group (15.2 ± 2.6 vs. 13.4 ± 1.3 min, 48.2 ± 7.7 vs. 41.5 ± 8.0 min, respectively, p < 0.001). However, the extubation times were similar between the two groups. The duration of the caudal block was longer in group D compared with the control group (8.8 ± 1.6 vs. 4.6 ± 0.7 h, p < 0.001). Conclusions: Caudal dexmedetomidine prolongs the duration of caudal block and decreases the incidence of postoperative agitation in children undergoing urethroplasty. Clinical Trial Registration: ChiCTR1800016828.