Intraoperative dexmedetomidine and acute kidney injury in paediatric noncardiac surgery: a retrospective propensity score-matched analysis

BACKGROUND

Paediatric acute kidney injury (AKI) is common and linked to longer hospitalisation and mortality. We investigated whether a continuous intraoperative infusion of dexmedetomidine, which increases renal blood flow, was associated with a lower risk of postoperative AKI in paediatric patients undergoing noncardiac surgery.

METHODS

This retrospective cohort study included paediatric patients undergoing noncardiac surgery between January 2019 and July 2021. Propensity score matching, based on the participants' baseline characteristics, was used to minimise the potential bias. The primary outcome was AKI within 7 days after surgery. The secondary outcomes included ICU admission, in-hospital mortality, length of hospitalisation, intraoperative bradycardia, and hypotension. The exposure of interest was continuous intraoperative infusion of dexmedetomidine at any dosage or duration. Multivariable logistic regression and linear regression analyses were further used to adjust for residual imbalanced intraoperative factors in the matched cohort.

RESULTS

After propensity score matching, we identified 1858/4091 paediatric patients who had received intraoperative dexmedetomidine infusion. Intraoperative dexmedetomidine infusion was associated with a lower risk of AKI (1.4% vs 3.2%; odds ratio 0.43, 95% confidence interval 0.27-0.66; P<0.001), postoperative ICU admission (odds ratio 0.35, 95% confidence interval 0.30-0.42; P<0.001), and shorter hospitalisation (7 [5-10] vs 9 [6-13] days; P<0.001). Intraoperative bradycardia, hypotension, and in-hospital mortality were similar between the matched groups.

CONCLUSIONS

This retrospective analysis of a single-centre paediatric noncardiac surgery cohort suggests that intraoperative dexmedetomidine infusion was associated with a lower incidence of AKI within 7 days after surgery.

CLINICAL TRIAL REGISTRATION

ChiCTR2300069115.

Scoping review finds insufficient evidence on potential risks of procedural sedation with dexmedetomidine in children

AIM

Dexmedetomidine is commonly used in hospitals for sedation during procedurals. It has been considered safe even though studies have shown that it may cause bradycardia and hypotension. The aim of this study was to map the current evidence regarding potential risks of sedation of children with dexmedetomidine.

METHODS

Two database searches were conducted to gather all articles published through 30 January 2024 that matched the inclusion criteria. PubMed and Embase were chosen for the initial search. Search terms were chosen to create a broad systematic search that would include articles reporting adverse events during procedural sedation on children. From the included articles, data on type of sedation, administration, patient characteristics, endpoints and number of adverse events were collected.

RESULTS

After the initial search, 357 individual papers were screened and 41 papers were included. The most common adverse event reported was bradycardia. In almost 40% of the articles that measured oxygen saturation, one or more incidents of desaturation occurred. 27% reported that interventions to prevent further harm were preformed, most of the interventions were to improve oxygenation.

CONCLUSION

There is a need for further investigation regarding adverse events, especially respiratory adverse events during sedation with dexmedetomidine.

Effective and safe pediatric sedation

Pediatric sedation is a crucial tool for minimizing pain and anxiety during procedures and examinations in children. However, it is not without risks. This review provides a comprehensive review of pediatric sedation, including both established practices and recent advancements. A thorough pre-procedural evaluation is crucial to mitigate these risks. Skilled healthcare professionals trained in pediatric sedation are paramount to ensure a safe and effective procedure. The choice of sedative medication depends on various factors, such as the type of procedure and the patient's medical condition. Medications, used alone or in combination, offer sedation with varying onset times and durations. Non-pharmacological approaches can complement pharmacological sedation and further reduce potential complications. Preventing sedation-related complications requires a multidisciplinary approach. This includes collaborative decision-making, vigilant monitoring throughout the procedure, and a focus on patient safety. Recovery involves ensuring the child returns to their baseline status before discharge, following established criteria. In conclusion, successful pediatric sedation hinges on a comprehensive strategy. This strategy encompasses a thorough evaluation, skilled personnel, appropriate medication selection, vigilant monitoring, and a focus on patient safety throughout the process. By following these steps, we can minimize risks and achieve successful outcomes.

Risk factors for chloral hydrate sedation failure in pediatric patients: a retrospective analysis

BACKGROUND

This study aimed to investigate the risk factors for chloral hydrate sedation failure and complications in a tertiary children's hospital in South Korea.

METHODS

A retrospective analysis of pediatric procedural sedation with chloral hydrate between January 1, 2021, and March 30, 2022, was performed. The collected data included patient characteristics, sedation history, and procedure. Multivariable regression analysis was performed to identify the risk factors for procedural sedation failure and complications.

RESULTS

A total of 6,691 procedural sedation were included in the analysis; sedation failure following chloral hydrate (50 mg/kg) occurred in 1,457 patients (21.8%) and was associated with a higher rate of overall complications compared to those with successful sedation (17.5% [225/1457] vs. 6.2% [322/5234]; P < 0.001, odds ratio: 3.236). In the multivariable regression analysis, the following factors were associated with increased risk of sedation failure: general ward or intensive care unit inpatient (compared with outpatient); congenital syndrome; oxygen dependency; history of sedation failure or complications with chloral hydrate; procedure more than 60 min; and magnetic resonance imaging, radiotherapy, or procedures with painful or intense stimuli (all P values < 0.05). Factors contributing to the complications included general ward inpatient, congenital syndromes, congenital heart disease, preterm birth, oxygen dependency, history of complications with chloral hydrate, and current sedation failure with chloral hydrate (all P values < 0.05).

CONCLUSIONS

To achieve successful sedation with chloral hydrate, the patient's sedation history, risk factors, and the type and duration of the procedure should be considered.

Dexmedetomidine in the Treatment of Depression: An Up-to-date Narrative Review

Depressive disorders (DD) are common, and their prevalence is expected to rise over the next decade. Depressive disorders are linked to significant morbidity and mortality. The clinical conundrum of depressive disorders lies in the heterogeneity of their phenomenology and etiology. Further, the currently available antidepressants have several limitations, including a delayed onset of action, limited efficacy, and an unfavorable side effect profile. In this review, Dexmedetomidine (DEX), a highly selective and potent α2-adrenergic receptor (α2-AR) agonist, is proposed as a potentially novel antidepressant with multiple mechanisms of action targeting various depression pathophysiological processes. These mechanisms include modulation of the noradrenergic system, regulation of neuroinflammation and oxidative stress, influence on the Brain-Derived Neurotrophic Factor (BDNF) levels, and modulation of neurotransmitter systems, such as glutamate. The review begins with an introduction before moving on to a discussion of DEX's pharmacological features. The pathophysiological and phenomenological targets of DD are also explored, along with the review of the existing preclinical and clinical evidence for DEX's putative anti-depressant effects. Finally, the review ends by presenting the pertinent conclusions and future directions.

Safety and effectiveness of the combination of remimazolam tosilate and propofol in gastroscopy: a multicenter, randomized controlled, single-blind clinical trial

Remimazolam tosilate (RT) is a new short-acting γ-aminobutyric acid A (GABAA) receptors agonist. However, its optimal use mode and dosage still remain unclear. This study aimed to examine the safety and effectiveness of the combination of RT and propofol in gastroscopy. This was a prospective, single-blind, randomized, multicenter, parallel-group study. All eligible 256 patients were randomized into the following 3 groups. Patients were anesthetized with propofol (Group P), RT (Group R) or the combination of RT and propofol (Group RP). The primary efficacy endpoints were: body movement score; satisfaction of gastroscopy doctors; success rate of sedation and effects on sleep status. Sedation induction time, time to be fully alert and adverse events were also recorded. The probability of complete immobility was lower in group R (33.73%) than in group P (86.67%) and RP (83.13%). The rate of doctors' satisfaction was much lower in group R (28.92%) than in group P (77.78%) and RP (72.29%). The success rate of sedation and sleep outcome score has no difference in the three groups. The time to adequate sedation was longer in group RP (77.27 ± 18.63 s) than in group P (64.47 ± 24.36 s), but much shorter than that in group R (102.84 ± 46.43s). The time to be fully alert was shorter in group R (6.30 ± 1.52 min) and RP (6.54 ± 1.13 min) than in group P (7.87 ± 1.08 min). The proportion of sedative hypotension was significantly higher in group P (41.11%) than in group R (1.20%) and group RP (3.61%) (p < 0.001). The incidence of respiratory depression was much higher in group P (17.78%) than in group R (no patient) and group RP (1.2%). The incidence of adverse events was lower in groups R (4.82%) and RP (9.64%) than in group P (31.11%). The combination of RT and propofol takes effect quickly, makes patients alert quickly, provides a sufficient depth of sedation, reduces body movement, does not inhibit circulation and respiratory function, does not affect sleep, and is the preferred mode for gastroscopy doctors and anesthesiologists.

The Effects of Dexmedetomidine on Children Undergoing Magnetic Resonance Imaging: A Systematic Review and Meta-Analysis

BACKGROUND

Magnetic Resonance Imaging (MRI) is a valuable diagnostic tool but often requires sedation to complete, especially in children. Dexmedetomidine (DEX) is an a2 agonist, for which there are experimental findings that support its potential neuroprotective effects. Given the potential risks of anesthetic drugs, we ran this study to examine DEX's effectiveness and cardiopulmonary safety as a sedative drug for children undergoing MRI.

MATERIAL AND METHODS

Systematic research was conducted in PubMed, Google Scholar, Scopus and Cochrane databases for randomized controlled trials published between 2010 and 6th/2022 and involving children undergoing MRI who received DEX as sedative medication. The records which met the including criteria, after indexing via the PRISMA chart and assessing for bias, were processed, and a meta-analysis was carried out with the random effects method.

RESULTS

Thirteen studies were included. Out of 6204 measurements obtained, in 4626, it was planned for the participants to only receive DEX (measure group) as an anesthetic drug throughout the procedure. The participants' mean age was 57 months (Ι² = 4%, τ² = 0.5317, p = 0.40). A total of 5.6% (95% CI: 0.6-14.1%, I² = 98%, p < 0.01) of the patients needed a second dose of DEX. In total, 6% (95% CI: 1-15%, I² = 93%, τ² = 0.0454, p < 0.01) required the administration of another drug, besides DEX, to complete the imaging (sedation failure). The effectiveness of the only-DEX method was 99% (95% CI: 97.5-100%, I² = 81%, τ² = 0.0107, p < 0.01). The whole rate of adverse events was 15% (95% CI: 9.3-21.5%, I² = 92%, p < 0.01). Hypotension was reported in 8.7% of the cases (95% CI: 3.1-16.4%, I² = 84%, p < 0.01), hypertension in 1.1% (95% CI: 0-5.4%, I² = 89%, p < 0.01), bradycardia in 10% (95% CI: 4-18%, I² = 95%, p < 0.01) and desaturation in 1.2% (95% CI: 0-4%, I² = 68%, p < 0.01). There was no statistically significant incidence in respiratory rate decrease (comparing the children who received DEX to their baseline). Five cases of vomiting and one of apnea were recorded.

CONCLUSIONS

Given that DEX seems to be an effective as well as respiratory and hemodynamically safe drug, it may be a future spotlight in (pediatric) sedation for imaging procedures such as MRI.

Two-center randomized controlled trial comparing oral chloral hydrate and intranasal combination of dexmedetomidine and ketamine for procedural sedation in children: study protocol

BACKGROUND

Oral chloral hydrate is widely used in pediatric sedation. Intranasal dexmedetomidine has been increasingly used for pediatric sedation; however, its improvement is warranted. The combination of dexmedetomidine with ketamine can improve onset and hemodynamic stability while maintaining sedative efficacy. This study aims to determine the efficacy and safety of intranasal combination of dexmedetomidine and ketamine compared to oral chloral hydrate.

METHODS

This is a prospective, parallel-arm, single-blinded, two-center, superiority randomized controlled trial with 1:1 allocation, designed to compare the effects of intranasal combination of dexmedetomidine and ketamine with those of oral chloral hydrate. We shall enroll 136 patients aged < 7 years old in this study. Prior to the procedure, we shall randomize each patient into the control group (oral chloral hydrate 50 mg/kg) or study group (intranasal dexmedetomidine 2 μg/kg and ketamine 3 mg/kg). The primary outcome will be the rate of achieving an adequate sedation level (6-point Pediatric Sedation State Scale 1, 2, or 3) within 15 min. In addition, we shall measure the sedation time, sedation failure rate, completion of procedure, adverse events, patient acceptance, and physician satisfaction.

DISCUSSION

This study will provide evidence of the efficacy and safety of the intranasal combination of dexmedetomidine and ketamine in comparison with oral chloral hydrate.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT04820205. Registered on 19th March 2021.

Dexmedetomidine and perioperative analgesia in children

Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.

Minimizing Motion Artifacts in Intravital Microscopy Using the Sedative Effect of Dexmedetomidine

Among intravital imaging instruments, the intravital two-photon fluorescence excitation microscope has the advantage of enabling real-time 3D fluorescence imaging deep into cells and tissues, with reduced photobleaching and photodamage compared with conventional intravital confocal microscopes. However, excessive motion of organs due to involuntary movement such as breathing may result in out-of-focus images and severe fluorescence intensity fluctuations, which hinder meaningful imaging and analysis. The clinically approved alpha-2 adrenergic receptor agonist dexmedetomidine was administered to mice during two-photon fluorescence intravital imaging to alleviate this problem. As dexmedetomidine blocks the release of the neurotransmitter norepinephrine, pain is suppressed, blood pressure is reduced, and a sedation effect is observed. By tracking the quality of focus and stability of detected fluorescence in two-photon fluorescence images of fluorescein isothiocyanate-sensitized liver vasculature in vivo, we demonstrated that intravascular dexmedetomidine can reduce fluorescence fluctuations caused by respiration on a timescale of minutes in mice, improving image quality and resolution. The results indicate that short-term dexmedetomidine treatment is suitable for reducing involuntary motion in preclinical intravital imaging studies. This method may be applicable to other animal models.

Recent Advances in the Clinical Value and Potential of Dexmedetomidine

Dexmedetomidine, a highly selective α2-adrenoceptor agonist, has sedative, anxiolytic, analgesic, sympatholytic, and opioid-sparing properties and induces a unique sedative response which shows an easy transition from sleep to wakefulness, thus allowing a patient to be cooperative and communicative when stimulated. Recent studies indicate several emerging clinical applications via different routes. We review recent data on dexmedetomidine studies, particularly exploring the varying routes of administration, experimental implications, clinical effects, and comparative advantages over other drugs. A search was conducted on the PubMed and Web of Science libraries for recent studies using different combinations of the words “dexmedetomidine”, “route of administration”, and pharmacological effect. The current routes, pharmacological effects, and application categories of dexmedetomidine are presented. It functions by stimulating pre- and post-synaptic α2-adrenoreceptors within the central nervous system, leading to hyperpolarization of noradrenergic neurons, induction of an inhibitory feedback loop, and reduction of norepinephrine secretion, causing a sympatholytic effect, in addition to its anti-inflammation, sleep induction, bowel recovery, and sore throat reduction effects. Compared with similar α2-adrenoceptor agonists, dexmedetomidine has both pharmacodynamics advantage of a significantly greater α2:α1-adrenoceptor affinity ratio and a pharmacokinetic advantage of having a significantly shorter elimination half-life. In its clinical application, dexmedetomidine has been reported to present a significant number of benefits including safe sedation for various surgical interventions, improvement of intraoperative and postoperative analgesia, sedation for compromised airways without respiratory depression, nephroprotection and stability of hypotensive hemodynamics, reduction of postoperative nausea and vomiting and postoperative shivering incidence, and decrease of intraoperative blood loss. Although the clinical application of dexmedetomidine is promising, it is still limited and further research is required to enhance understanding of its pharmacological properties, patient selection, dosage, and adverse effects.

Dexmedetomidine & perioperative analgesia in children

Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.

The 90% effective dose of intranasal dexmedetomidine for procedural sedation in children with congenital heart disease before and after surgery: A biased-coin design up-and-down sequential allocation trial

BACKGROUND

Intranasal dexmedetomidine can provide adequate sedation during short procedures. However, there are few reports investigating the effective dose of intranasal dexmedetomidine for sedation in children with congenital heart disease (CHD) before and after surgery.

METHODS

Children aged 13-36 months with acyanotic CHD requiring trans-thoracic echocardiography before cardiac surgery were recruited for this study. One month after the cardiac surgery, the same children were studied again. The 90% effective dose was established using a biased-coin design up-and-down sequential method. Onset time, examination time, wake-up time and adverse effects were measured. Safety was evaluated in terms of changes in vital signs.

RESULTS

A total of fifty-eight subjects were recruited for this study. The 90% effective dose of intranasal dexmedetomidine for sedation was 2.13 μg/kg (95% CI, 1.73-2.34 μg/kg) in children with CHD before cardiac surgery and 3.51 μg/kg (95% CI, 2.99-3.63 μg/kg) after cardiac surgery (P < .01). There were no differences between the groups in terms of demographic variables, onset time, examination time, wake-up time or adverse effects.

CONCLUSIONS

The 90% effective dose of intranasal dexmedetomidine for sedation in children with CHD was 2.13 μg/kg before cardiac surgery and 3.51 μg/kg after cardiac surgery.

Remimazolam tosilate in upper gastrointestinal endoscopy: A multicenter, randomized, non-inferiority, phase III trial

BACKGROUND AND AIM

Remimazolam tosilate (RT) is a new short-acting GABA(A) receptor agonist, having potential to be an effective option for procedural sedation. Here, we aimed to compare the efficacy and safety of RT with propofol in patients undergoing upper gastrointestinal endoscopy.

METHODS

This positive-controlled, non-inferiority, phase III trial recruited patients at 17 centers, between September 2017 and November 2017. A total of 384 patients scheduled to undergo upper gastrointestinal endoscopy were randomly assigned to receive RT or propofol. Primary endpoint was the success rate of sedation. Adverse events (AEs) were recorded to evaluate safety.

RESULTS

The success rate of sedation in the RT group was non-inferior to that in the propofol group (97.34% vs 100.00%; difference in rate -2.66%, 95% CI -4.96 to -0.36, meeting criteria for non-inferiority). Patients in the RT group had longer time to adequate sedation (P < 0.0001) but shorter time to fully alert (P < 0.0001) than that in the propofol group. The incidences of hypotension (13.04% vs 42.86%, P < 0.0001), treatment-related hypotension (0.54% vs 5.82%, P < 0.0001), and respiratory depression (1.09% vs 6.88%, P = 0.0064) were significantly lower in the RT group. AEs were reported in 74 (39.15%) patients in the RT group and 114 (60.32%) patients in the propofol group, with significant difference (P < 0.0001).

CONCLUSION

This trial established non-inferior sedation success rate of RT compared with propofol. RT allows faster recovery from sedation compared with propofol. The safety profile is favorable and appears to be superior to propofol, indicating that it was feasible and well tolerated for patients.

Effects of dexmedetomidine as an adjuvant in thoracic paravertebral block on EC50 of propofol for successful laryngeal mask insertion: a randomized controlled trial

Background

Dexmedetomidine as an adjuvant can improve the duration and the quality of thoracic paravertebral block (TPVB); however, its quantitative effect on propofol infusion is unclear. This study aimed to investigate the effect of dexmedetomidine as an adjuvant in TPVB on the medium effective concentration (EC50) of propofol for successful laryngeal mask insertion.

Methods

Sixty breast cancer patients who underwent elective modified radical mastectomy were enrolled and randomized at a 1:1 ratio into control group (Group C, n=30) or dexmedetomidine group (Group D, n=30). Ultrasound-guided T3 paravertebral block was performed before induction of anesthesia. In Group C, 0.5% ropivacaine 0.3 mL/kg was injected into T3 paravertebral space, while subjects in Group D received 0.5% ropivacaine 0.3 mL/kg with dexmedetomidine (1 µg/kg). Propofol target-controlled infusion (TCI) was performed, with an initial target effect-site concentration of 5 µg/mL determined for both groups. The laryngeal mask was inserted once the effect chamber achieved the target concentration. Subsequent target concentrations were adjusted by Dixon up-down sequential method, where dose modifications were performed by 0.5 mg/mL intervals, based on the success of the laryngeal mask insertion. Probit analysis was used to determine the propofol EC50. Mean arterial pressure (MAP), heart rate (HR), bispectral index (BIS) and application of atropine or ephedrine was recorded. Participants, TPVB giver, and data recorder were blinded to group assignment.

Results

Propofol EC50 for successful laryngeal mask insertion were statistically significant, with 5.256 µg/mL (95% CI: 4.833, 5.738 µg/mL) in Group C and 3.172 µg/mL (95% CI: 2.701, 3.621 µg/mL) in Group D. Both groups displayed significantly lower MAP and HR, post propofol TCI (P<0.05). However, subjects in Group D exhibited lower MAP and HR levels compared to patients in Group C (P<0.05). Application of atropine (0% vs. 10%) and ephedrine (20.0% vs. 13.3%) were not significantly different between two groups.

Conclusions

Dexmedetomidine, administered as an adjuvant in TPVB, can reduce the TCI concentration of propofol for successful laryngeal mask placement in females. The target concentration of propofol requires adjustment and close monitoring of hemodynamic changes, post induction is warranted.

Trial registration

Chinese Clinical Trial Registry ChiCTR1800016614.

[Comparison of ED50 of intranasal dexmedetomidine sedation in children with acyanotic congenital heart disease before and after cardiac surgery]

OBJECTIVE

To compare the median effective dose (ED50) of intranasal dexmedetomidine for procedural sedation in uncooperative pediatric patients with acyanotic congenital heart disease before and after cardiac surgery.

METHODS

We prospectively recruited 47 children (22 in preoperative group and 25 in postoperative group) who needed sedation for transthoracic echocardiography (TTE). A modified up-and-down sequential study design was employed to determine dexmedetomidine dose for each patient with a starting dose of 2 μg/kg in both groups; dexmedetomidine doses for subsequent subjects were determined according to the responses from the previous subject using the up-and-down method at a 0.25 μg/kg interval. The ED95 was determined using probit regression. The onset time, examination time, wake-up time and adverse effects were measured, and the safety was evaluated in terms of changes in vital signs every 5 min.

RESULTS

The ED50 value of intranasal dexmedetomidine for sedation was 1.84 μg/kg (95% CI: 1.68-2.00 μg/kg) in children with congenital heart disease before cardiac surgery, and 3.38 μg/kg (95% CI: 3.21-3.54 μg/kg) after the surgery. No significant difference was found between the two groups in the demographic variables, onset time, examination time, wake-up time, or adverse effects.

CONCLUSIONS

In children with acyanotic congenital heart disease, the ED50 of intranasal dexmedetomidine for TTE sedation increases to 3.38 μg/ kg after cardiac surgery from the preoperative value of 1.84 μg/kg.

Intramuscular dexmedetomidine and oral chloral hydrate for pediatric sedation for electroencephalography: A propensity score-matched analysis

BACKGROUND

Intramuscular dexmedetomidine can be used for pediatric sedation without requiring intravenous access and has advantages for electroencephalography by inducing natural sleep pathway, but only a limited number of studies compared the efficacy of intramuscular dexmedetomidine with oral chloral hydrate.

AIMS

To compare the efficacy and safety of intramuscular dexmedetomidine and oral chloral hydrate used for sedation during electroencephalography in pediatric patients.

METHODS

We reviewed the medical records of pediatric patients who underwent sedation for electroencephalography between January 2015 and December 2016. Initial doses of dexmedetomidine and chloral hydrate were 3 mcg/kg and 50 mg/kg, respectively; second doses (1 mcg/kg and 50 mg/kg, respectively) were administered if adequate sedation was not achieved. Demographic data, time of sedative administration, time of sedation and awakening, and time of arrival at recovery room and discharge were analyzed.

RESULTS

Out of a total of 1239 patients, 125 patients had received dexmedetomidine and 1114 had received chloral hydrate. After 1:1 propensity score matching, the dexmedetomidine and chloral hydrate groups each had 118 patients. Testing completion rate with a single dose of medication was higher in the dexmedetomidine group (91.5% vs 71.2%; mean difference [95% CI] 20.3 [10.8-29.9]; P < .0001; Pearson chi-square value = 16.09). Sedation onset time was shorter in the dexmedetomidine group as well (16.6 ± 13.0 minutes vs 41.5 ± 26.8 minutes; mean difference [95% CI] 24.8 [19.1-30.6]; P < .0001; T = 8.27). On the contrary, the duration of recovery was longer in the dexmedetomidine group (35.5 ± 40.2 minutes vs 18.5 ± 30.7 minutes; mean difference [95% CI] 18.6 [8.8-28.5]; P = .0002; T = -2.82). Total residence time was not significantly different between the two groups (125.8 ± 40.6 minutes vs 122.1 ± 42.2 minutes, mean difference [95% CI] 5.21 [6.1-16.5], P = .3665 T = 0.04).

CONCLUSIONS

Intramuscular dexmedetomidine showed higher sedation success rate and shorter time to achieving the desired sedation level compared with oral chloral hydrate and thus may be an effective alternative for oral chloral hydrate in pediatric patients requiring sedation for electroencephalography.

Intranasal dexmedetomidine is an effective sedative agent for electroencephalography in children

BACKGROUND

Intranasal dexmedetomidine (DEX), as a novel sedation method, has been used in many clinical examinations of infants and children. However, the safety and efficacy of this method for electroencephalography (EEG) in children is limited. In this study, we performed a large-scale clinical case analysis of patients who received this sedation method. The purpose of this study was to evaluate the safety and efficacy of intranasal DEX for sedation in children during EEG.

METHODS

This was a retrospective study. The inclusion criteria were children who underwent EEG from October 2016 to October 2018 at the Children's Hospital affiliated with Chongqing Medical University. All the children received 2.5 μg·kg^- 1 of intranasal DEX for sedation during the procedure. We used the Modified Observer Assessment of Alertness/Sedation Scale (MOAA/S) and the Modified Aldrete score (MAS) to evaluate the effects of the treatment on sedation and resuscitation. The sex, age, weight, American Society of Anesthesiologists physical status (ASAPS), vital signs, sedation onset and recovery times, sedation success rate, and adverse patient events were recorded.

RESULTS

A total of 3475 cases were collected and analysed in this study. The success rate of the initial dose was 87.0% (3024/3475 cases), and the success rate of intranasal sedation rescue was 60.8% (274/451 cases). The median sedation onset time was 19 mins (IQR: 17-22 min), and the sedation recovery time was 41 mins (IQR: 36-47 min). The total incidence of adverse events was 0.95% (33/3475 cases), and no serious adverse events occurred.

CONCLUSIONS

Intranasal DEX (2.5 μg·kg^- 1) can be safely and effectively used for EEG sedation in children.

Sedatives used in children to obtain head CT in the emergency department

OBJECTIVES

Children in the emergency department who require computerized tomography (CT) of the head often are given sedative medications to facilitate completion of the study with adequate imaging. A prior study found the two most common medications used to obtain head CT in children were pentobarbital and chloral hydrate; however, these medications have become less popular. We hypothesized that there was variability in medication choice amongst providers in the emergency department and there has been a change in the preferred sedatives used in the last decade.

METHODS

We conducted a retrospective multicenter cross-sectional study of children 0-18 years old who received a medication with sedative properties and underwent head CT while in the emergency department from 2007 to 2018, using the Pediatric Health Information System (PHIS) database. The primary outcome measure was the frequency of administration of drugs within an individual sedative class.

RESULTS

We analyzed 24,418 patient encounters, of whom 53% received an opioid and 41% received a benzodiazepine. There were statistically significant decreases in the use of barbiturates, chloral hydrate, anti-emetic sedatives, and opioids, while increases in barbiturate combination drugs, benzodiazepines and dexmedetomidine were observed over the study period. The majority of medications were administered parenterally.

CONCLUSION

There is wide variability in sedatives used in children to obtain head CT and the preferred drugs have shifted over the last decade.

Randomised Comparison between the Efficacy of Two Doses of Nebulised Dexmedetomidine for Premedication in Paediatric Patients

Objective

Nebulised dexmedetomidine can be an easy alternative for preoperative sedation in paediatric patients, but data regarding its efficacy are very limited.

Methods

This prospective, randomised, double-blind study included 66 patients aged between 1 and 8 years. Patients were divided into two groups as D2 and D3. The D2 group received 2 μg kg⁻¹ of nebulised dexmedetomidine, and the D3 group received 3 μg kg⁻¹ of nebulised dexmedetomidine preoperatively. All the patients received general anaesthesia and caudal epidural analgesia with 0.75 mL kg⁻¹ of 0.2% ropivacaine. Parental Separation Anxiety Scale at 30 min after the end of nebulisation, Mask Acceptance Score (MAS) during induction, haemodynamic variables, emergence agitation and duration of caudal analgesia were compared between the groups. Statistical analysis was done using Mann-Whitney U test and chi-square test. A p-value <0.05 was accepted as significant.

Results

All the parameters were comparable between the D2 and D3 groups; however, significantly more number of younger children was observed in the D3 group. Hence, further analysis was done after division into the lower age (1–3 years) and higher age (4–8 years) groups. In lower age group children, satisfactory parental separation was achieved in 100% of the patients in the D3 group compared to 20% of those in the D2 group (p=0.00). MAS was significantly better in the D3 group in both the lower (p=0.019) and higher (p=0.036) age groups.

Conclusion

We conclude that nebulised dexmedetomidine in a dose of 3 μg kg⁻¹ provides better parental separation and mask acceptance in younger children.

Safety and Efficacy of Buccal Dexmedetomidine for MRI Sedation in School-Aged Children

OBJECTIVES

Intranasal, intramuscular, and intravenous (IV) dexmedetomidine routes have been used successfully for pediatric MRI studies. We designed this retrospective study to determine efficacy and safety of buccal dexmedetomidine for pediatric MRI sedation.

METHODS

Medical records were reviewed of outpatient children ages 5 to 18 years who received buccal dexmedetomidine with or without oral midazolam for MRI sedation at a freestanding children's hospital sedation program in 2015 and 2016.

RESULTS

A total of 220 outpatient encounters received buccal dexmedetomidine for MRI. Mean age of the cohort was 10.1 ± 2.6 years (range: 5-18.7). Buccal dexmedetomidine dose administered was a mean of 2.20 ± 0.38 μg/kg (range: 0.88-3.19). Of the 220 sedation encounters, 179 (81.4%) patients had satisfactory sedation with buccal dexmedetomidine with or without oral midazolam: 84 had buccal dexmedetomidine as the sole sedative, 95 had satisfactory sedation when buccal dexmedetomidine and oral midazolam (mean: 0.33 ± 0.07 mg/kg; range: 0.21-0.53) were given together, 1 (0.4%) had satisfactory sedation when intranasal fentanyl and midazolam were administered in addition to buccal dexmedetomidine, and 35 (15.9%) required IV sedatives to achieve satisfactory sedation. All patients completed their MRI successfully except 5 (2.2%): 2 encounters were sedation failures, 2 IV sedations developed severe upper airway obstruction, and 1 IV sedation experienced MRI contrast anaphylaxis.

CONCLUSIONS

In a selected population of pediatric patients, buccal dexmedetomidine with or without midazolam provides adequate sedation for most MRI studies with few adverse effects, but given a failure rate of almost 20%, modifications to buccal dexmedetomidine dosing should be investigated.

Feasibility of measuring memory response to increasing dexmedetomidine sedation in children

BACKGROUND

The memory effect of dexmedetomidine has not been prospectively evaluated in children. We evaluated the feasibility of measuring memory and sedation responses in children during dexmedetomidine sedation for non-painful radiological imaging studies. Secondarily, we quantified changes in memory in relation to the onset of sedation.

METHODS

A 10 min bolus of dexmedetomidine (2 mcg kg^-1) was given to children as they named simple line drawings every five s. The absence of sedation was identified as any verbal response, regardless of correctness. After recovery, recognition memory was tested with correct Yes/No recognitions (50% novel pictures) and was matched to sedation responses during the bolus period (subsequent memory paradigm).

RESULTS

Of 64 accruals, 30 children (mean [SD]6.1 (1.2) yr, eight male) received dexmedetomidine and completed all study tasks. Individual responses were able to be modelled successfully in the 30 children completing all the study tasks, demonstrating feasibility of this approach. Children had 50% probability of verbal response at five min 40 s after infusion start, whereas 50% probability of subsequent recognition memory occurred sooner at four min five s.

CONCLUSIONS

Quantifying memory and sedation effects during dexmedetomidine infusion in verbal children was possible and demonstrated that memory function was present until shortly before verbal unresponsiveness occurred. This is the first study to investigate the effect of dexmedetomidine on memory in children.

CLINICAL TRIAL REGISTRATION

NCT 02354378.

Sedation and analgesia for procedures in the pediatric emergency room

OBJECTIVE

Children and adolescents often require sedation and analgesia in emergency situations. With the emergence of new therapeutic options, the obsolescence of others, and recent discoveries regarding already known drugs, it became necessary to review the literature in this area.

DATA SOURCES

Non-systematic review in the PubMed database of studies published up to December 2016, including original articles, review articles, systematic reviews, and meta-analyses. References from textbooks, publications from regulatory agencies, and articles cited in reviews and meta-analyses through active search were also included.

DATA SYNTHESIS

Based on current literature, the concepts of sedation and analgesia, the necessary care with the patient before, during, and after sedoanalgesia, and indications related to the appropriate choice of drugs according to the procedure to be performed and their safety profiles are presented.

CONCLUSIONS

The use of sedoanalgesia protocols in procedures in the pediatric emergency room should guide the professional in the choice of medication, the appropriate material, and in the evaluation of discharge criteria, thus assuring quality in care.

Intranasal Dexmedetomidine for Procedural Sedation in Children, a Suitable Alternative to Chloral Hydrate

Sedation is often required for children undergoing diagnostic procedures. Chloral hydrate has been one of the sedative drugs most used in children over the last 3 decades, with supporting evidence for its efficacy and safety. Recently, chloral hydrate was banned in Italy and France, in consideration of evidence of its carcinogenicity and genotoxicity. Dexmedetomidine is a sedative with unique properties that has been increasingly used for procedural sedation in children. Several studies demonstrated its efficacy and safety for sedation in non-painful diagnostic procedures. Dexmedetomidine's impact on respiratory drive and airway patency and tone is much less when compared to the majority of other sedative agents. Administration via the intranasal route allows satisfactory procedural success rates. Studies that specifically compared intranasal dexmedetomidine and chloral hydrate for children undergoing non-painful procedures showed that dexmedetomidine was as effective as and safer than chloral hydrate. For these reasons, we suggest that intranasal dexmedetomidine could be a suitable alternative to chloral hydrate.

Influence of Scan Duration on Pulmonary Capillary Hemorrhage Induced by Diagnostic Ultrasound

Diagnostic ultrasound can induce pulmonary capillary hemorrhage (PCH) in rats and display this as "comet tail" artifacts (CTAs) after a time delay. To test the hypothesis that no PCH occurs for brief scans, anesthetized rats were scanned using a 6-MHz linear array for different durations. PCH was characterized by ultrasound CTAs, micro-computed tomography (μCT), and measurements of fixed lung tissue. The μCT images revealed regions of PCH, sometimes penetrating the entire depth of a lobe, which were reflected in the fixed tissue measurements. At -3 dB of power, PCH was substantial for 300-s scans, but not significant for 25-s scans. At 0 dB, PCH was not strongly dependent on scan durations of 300 to 10 s. Contrary to the hypothesis, CTAs were not evident during most 10-s scans (p > 0.05), but PCH was significant (p = 0.02), indicating that PCH could occur without evidence of the injury in the images.

The Influence of Dexmedetomidine on Ultrasound-induced Pulmonary Capillary Hemorrhage in Rats

The use of xylazine, a veterinary sedative, with ketamine for rat anesthesia has been shown to enhance the pulmonary capillary hemorrhage (PCH) effect of diagnostic ultrasound. This study was undertaken to assess whether the sedative/analgesic dexmedetomidine, commonly used in the intensive care unit, can also enhance ultrasound-induced PCH. Female Sprague Dawley rats were anesthetized with various combinations of ketamine plus xylazine or dexmedetomidine. The dosage of dexmedetomidine was reduced for some groups to doses relevant to human clinical usage. The right thorax of all rats was shaved and depilated for ultrasound transmission and the rats were scanned with diagnostic ultrasound using a 7.6-MHz linear array in a 38°C de-gassed water bath. There was no significant difference in PCH results for the recommended anesthetic dosages of ketamine plus xylazine and ketamine plus 500 μg/kg dexmedetomidine. The varied doses of dexmedetomidine enhanced the PCH, even for the lowest dose of 4 μg/kg, equivalent to a low human dose of 0.64 μg/kg. There was no significant difference in PCH for 500 μg/kg dexmedetomidine with or without ketamine. Further research is needed to identify and characterize other factors that may modify the patient risk from ultrasound-induced PCH.

Options and Considerations for Procedural Sedation in Pediatric Imaging

As pediatric imaging capabilities have increased in scope, so have the complexities of providing procedural sedation in this environment. While efforts by many organizations have dramatically increased the safety of pediatric procedural sedation in general, radiology sedation creates several special challenges for the sedation provider. These challenges require implementation of additional safeguards to promote safety during sedation while maintaining effective and efficient care. Multiple agent options are available, and decisions regarding which agent(s) to use should be determined by both patient needs (i.e., developmental capacities, underlying health status, and previous experiences) and procedural needs (i.e., duration, need for immobility, and invasiveness). Increasingly, combinations of agents to either achieve the conditions required or mitigate/counterbalance adverse effects of single agents are being utilized with success. To continue to provide effective imaging sedation, it is incumbent on sedation providers to maintain familiarity with continuing evolutions within radiology environments, as well as comfort and competence with multiple sedation agents/regimens. This review discusses the challenges associated with radiology sedation and outlines various available agent options and combinations, with the intent of facilitating appropriate matching of agent(s) with patient and procedural needs.

Assessment of Inflammation in an Acute on Chronic Model of Inflammatory Bowel Disease with Ultrasound Molecular Imaging

BACKGROUND

Ultrasound (US) molecular imaging has shown promise in assessing inflammation in preclinical, murine models of inflammatory bowel disease. These models, however, initiated acute inflammation on previously normal colons, in contrast to patients where acute exacerbations are often in chronically inflamed regions. In this study, we explored the potential of dual P- and E-selectin targeted US imaging for assessing acute inflammation on a murine quiescent chronic inflammatory background.

METHODS

Chronic colitis was induced using three cycles of 4% DSS in male FVB mice. Acute inflammation was initiated 2 weeks after the final DSS cycle through rectal administration of 1% TNBS. Mice at different stages of inflammation were imaged using a small animal ultrasound system following i.v. injection of microbubbles targeted to P- and E-selectin. In vivo imaging results were correlated with ex vivo immunofluorescence and histology.

RESULTS

Induction of acute inflammation resulted in an increase in the targeted US signal from 5.5 ± 5.1 arbitrary units (a.u.) at day 0 to 61.0 ± 45.2 a.u. (P < 0.0001) at day 1, 36.3 ± 33.1 a.u. at day 3, returning to levels similar to control at day 5. Immunofluorescence showed significant increase in the percentage of P- and E-selectin positive vessels at day 1 (P-selectin: 21.0 ± 7.1% of vessels; P < 0.05; E-selectin: 16.4 ±3.7%; P < 0.05) compared to day 0 (P-selectin: 10.3 ± 5.7%; E-selectin: 7.3 ± 7.0%).

CONCLUSIONS

Acute inflammation can be accurately measured in a clinically relevant murine model of chronic IBD using ultrasound molecular imaging with a dual P- and E- selectin-targeted contrast agent.

Intranasal dexmedetomidine for sedation for pediatric computed tomography imaging

This prospective observational pilot study evaluated the aerosolized intranasal route for dexmedetomidine as a safe, effective, and efficient option for infant and pediatric sedation for computed tomography imaging. The mean time to sedation was 13.4 minutes, with excellent image quality, no failed sedations, or significant adverse events.

TRIAL REGISTRATION

Registered with ClinicalTrials.gov: NCT01900405.

A prospective, randomized, double blinded comparison of intranasal dexmedetomodine vs intranasal ketamine in combination with intravenous midazolam for procedural sedation in school aged children undergoing MRI

Background:

For optimum magnetic resonance imaging (MRI) image quality and to ensure precise diagnosis, patients have to remain motionless. We studied the effects of intranasal dexmedetomidine and ketamine with intravenous midazolam for pre-procedural and procedural sedation in school aged children.

Patients and Methods:

Children were randomly allocated to one of two groups: (Group D) received intranasal dexmedetomidine 3 μg kg^–1 and (Group K) received intranasal ketamine 7 mg kg^–1. Sedation levels 10, 20 and 30 min after drug instillation were evaluated using a Modified Ramsay sedation scale. A 4-point score was used to evaluate patients when they were separated from their parents and their response to intravenous cannulation.

Results:

The two groups were comparable in terms of the child's anxiety at presentation (P = 0.245). We observed that Group K achieved faster sedation at 10 min point with P < 0.05. A comparable sedation score at 20 and 30 min were noted. The two groups were comparable regarding to the child's acceptance of nasal administration (P = 0.65). The sedation failure rate was insignificantly differ between groups (13.7% vs. 20.6% for Group D and K respectively). Heart rate and systolic blood pressure showed a significant difference between the two groups starting from the point of 20 min.

Conclusion:

Intranasal dexmedetomidine 3 μg kg^–1 or ketamine 7 mg kg^–1 can be used safely and effectively to induce a state of moderate conscious sedation and to facilitate parents’ separation and IV cannulation. Addition of midazolam in a dose not sufficient alone to produce the target sedation achieved our goal of deep level of sedation suitable for MRI procedure.

Bradycardia in perspective-not all reductions in heart rate need immediate intervention

According to Wikipedia, the word 'bradycardia' stems from the Greek βραδύς, bradys, 'slow', and καρδία, kardia, 'heart'. Thus, the meaning of bradycardia is slow heart rate but not necessarily too slow heart rate. If looking at top endurance athletes they may have a resting heart rate in the very low thirties without needing emergent intervention with anticholinergics, isoprenaline, epinephrine, chest compressions or the insertion of an emergency pacemaker (Figure 1). In fact, they withstand these episodes without incident, accommodating with a compensatory increase in stroke volume to preserve and maintain cardiac output. With this in mind, it is difficult for the authors to fully understand and agree with the general sentiment amongst many pediatric anesthesiologists that all isolated bradycardia portends impending doom and must be immediately treated with resuscitative measures.

Dexmedetomidine in current anaesthesia practice- a review

Dexmedetomidine is an alpha 2 adrenergic receptor agonist, even ten times more selective than clonidine. It is a very versatile drug in anaesthesia practice, finding place in increasing number of clinical scenarios and is no more limited to intensive care unit (ICU) sedation. It is analgesic, has anaesthetic sparing effect, sympatholytic property, useful in other procedural sedation and also has cardiovascular stabilizing property. It reduces delirium and preserves respiratory function which adds benefits to its uses. The aim of this review is to make awareness of its role in present anaesthesia and discuss its limitations at the same time.

Pediatric sedation

Pediatric sedation is an evolving field performed by an extensive list of specialties. Well-defined sedation systems within pediatric facilities are paramount to providing consistent, safe sedation. Pediatric sedation providers should be trained in the principles and practice of sedation, which include patient selection, pre-sedation assessment to determine risks during sedation, selection of optimal sedation medication, monitoring requirements, and post-sedation care. Training, credentialing, and continuing sedation education must be incorporated into sedation systems to verify and monitor the practice of safe sedation. Pediatric hospitalists represent a group of providers with extensive pediatric knowledge and skills who can safely provide pediatric sedation.

[Awake craniotomy. Considerations in special situations]

Awake craniotomy was the earliest surgical procedure known, and it has become fashionable again. In the past it was used for the surgical management of intractable epilepsy, but nowadays, its indications are increasing, and it is a widely recognized technique for the resection of mass lesions involving the eloquent cortex, and for deep brain stimulation. The procedure is safe, provides excellent results, and saves money and resources. The anesthesiologist should know the principles underlying neuroanesthesia, the technique of scalp blockade, and the sedation protocols, as well as feeling comfortable with advanced airway management. The main anesthetic aim is to keep patients cooperating when required (analgesia-based anesthesia). This review attempts to summarize the most recent evidence from the clinical literature, a long as the number of patients undergoing craniotomies in the awake state are increasing, specifically in the pediatric population.

Comparison between intranasal dexmedetomidine and intranasal ketamine as premedication for procedural sedation in children undergoing MRI: a double-blind, randomized, placebo-controlled trial

INTRODUCTION

Providing anesthesia to children undergoing MRI is challenging. Adequate premedication, administered noninvasively, would make the process smoother. In this study, we compare the efficacy of intranasal dexmedetomidine (DXM) with the intranasal administration of ketamine for procedural sedation in children undergoing MRI.

METHODS

We studied 150 children, between 1 and 10 years of age, divided randomly into three groups (DXM, K, and S). For blinding, every child received the intranasal drugs twice; syringe S1, 60 min before, and syringe S2, 30 min before intravenous (IV) cannulation. For children in group DXM, S1 contained DXM (1 μg/kg) and S2 was plain saline. Children in group K received saline in S1 and ketamine (5 mg/kg) in S2 whereas children in group S received saline in both S1 and S2. The child's response to drug administration, ease of IV cannulation, the satisfaction of the anesthesiologist and child's parents with the premedication, and the total propofol dose required for the satisfactory conduct of the procedure were compared. We also compared the time to awakening and discharge of the child as well as the occurrence of any side effects with these drugs.

RESULTS

Both DXM and ketamine were equally effective as premedication in these patients. Most of the children accepted the intranasal drugs with minimal discomfort; 90.4 % of the anesthesiologists in the DXM group and 82.7 % in the ketamine group were satisfied with the conditions for IV cannulation whereas only 21.3 % were satisfied in the saline group. The total dose of propofol used was less in the study groups. Furthermore, children in group DXM and group K had earlier awakening and discharge than those in group S.

CONCLUSION

DXM and ketamine were equally effective, by the intranasal route, as premedication in children undergoing MRI.