Efficacy of Dexmedetomidine as a Sole Sedative Agent in Small Diagnostic and Therapeutic Procedures: A Systematic Review

Evaluating the Quality of Systematic Reviews on Pediatric Sedation in Dentistry: An Umbrella Review

Sedation is a depression of a patient's state of consciousness, induced by medications, that can reach different levels of intensity during a medical procedure. Conscious sedation produces a minimally depressed level of consciousness without impairment of the ability to maintain an open airway, of protective reflexes or of responses to verbal and physical stimulation. This umbrella review is aimed at critically assessing the available systematic reviews (SRs) and meta-analyses (MA) on sedation in children/adolescents. An electronic database search was conducted that included Pubmed-Medline, Web of Science, Cochrane, Scopus, Scielo, Embase, LILACS and TRIP and the scope of which extended until January 2023. The risk of bias (RoB) of SRs was analyzed using the Measurement Tool to Assess SRs criteria 2 (AMSTAR2). Of 998 entries, 37 SRs were included. In terms of methodological quality, eight studies were assessed as having critically low quality, four studies had low quality, nine studies had moderate quality, and sixteen were considered to be of high quality. Based on the current guidelines, the most employed drugs in pediatric dentistry for sedation are nitrous oxide and midazolam; however, the available evidence supporting their use is insufficient and of low/critically low quality. The combined technique is recommended (nitrous oxide (30-50%) + midazolam). The optimal dose of oral midazolam is 0.75 mg/kg. The level of methodological quality of SRs is expected to increase according to the results and future directions of this umbrella review.

Intranasal dexmedetomidine for sedation in ABR testing in children: No pain, big gain!

OBJECTIVES

Obtaining perfect immobility or sleep in children undergoing ABR auditory brainstem response) testing can be challenging. We examined the effectiveness and safety of intranasal dexmedetomidine for sedation of children undergoing ABR testing.

MATERIAL AND METHODS

We included prospectively all patients aged from 1 to 15 years for whom sedation for ABR testing was required, between July 2018 and November 2021. We administered an initial dose of 2.5 μg/kg intranasal dexmedetomidine with a repeat dose of 1 μg/kg if needed 30 min later. Collected data included success rate of sedation, sedation onset and recovery times and incidence of side effects.

RESULTS

ABR testing was undertaken successfully in 57 of the 59 patients, giving a total success rate of 96,6 %. (95 % confidence interval 88.5 %-99.1 %). The median time to onset of sleep was 32 ± 18.3 min. The median duration of sedation recovery time was 48 ± 24.7 min. We recorded the adverse effects. Thirty-one patients experienced bradycardia and 28 patients experienced hypotension, all of which resolved without intervention.

CONCLUSION

Intranasal dexmedetomidine is an effective, safe, simple of use and noninvasive method for sedation in children. It could have a major role in auditory brainstem response testing, specially in the case of non-cooperative children.

REGISTRATION NUMBER OF THE TRIAL

NCT03530371.

Optimal Dose of Intranasal Dexmedetomidine for Laceration Repair in Children: A Phase II Dose-Ranging Study

STUDY OBJECTIVE

To determine the optimal sedative dose of intranasal dexmedetomidine for children undergoing laceration repair.

METHODS

This dose-ranging study employing the Bayesian Continual Reassessment Method enrolled children aged 0 to 10 years with a single laceration (<5 cm), requiring single-layer closure, who received topical anesthetic. Children were administered 1, 2, 3, or 4 mcg/kg intranasal dexmedetomidine. The primary outcome was the proportion with adequate sedation (Pediatric Sedation State Scale score of 2 or 3 for ≥90% of the time from sterile preparation to tying of the last suture). Secondary outcomes included the Observational Scale of Behavior Distress-Revised (range: 0 [no distress] to 23.5 [maximal distress]), postprocedure length of stay, and adverse events.

RESULTS

We enrolled 55 children (35/55 [64%] males; median [interquartile range {IQR}] age 4 [2, 6] years). At 1, 2, 3, and 4 mcg/kg intranasal dexmedetomidine, respectively, the proportion of participants "adequately" sedated was 1/3 (33%), 2/9 (22%), 13/21 (62%), and 12/21 (57%); the posterior mean (95% equitailed credible intervals) for the probability of adequate sedation was 0.38 (0.04, 0.82), 0.25 (0.05, 0.54), 0.61 (0.41, 0.80), and 0.57 (0.36, 0.76); the median (IQR) Observational Scale of Behavior Distress-Revised scores during suturing was 2.7 (0.3, 3), 0 (0, 3.8), 0.6 (0, 5), and 0 (0, 3.7); the median (IQR) postprocedure length of stay was 67 (60, 78), 76 (60, 100), 89 (76, 109), and 113 (76, 150) minutes. There was 1 adverse event, a decrease in oxygen saturation at 4 mcg/kg, which resolved with head repositioning.

CONCLUSION

Despite limitations, such as our limited sample size and subjectivity in Pediatric Sedation State Scale scoring, sedation efficacy for 3 and 4 mcg/kg were similarly based on equitailed credible intervals suggesting either could be considered optimal.

Nanoengineered Gallium Ion Incorporated Formulation for Safe and Efficient Reversal of PARP Inhibition and Platinum Resistance in Ovarian Cancer

Platinum-based chemotherapy remains the main systemic treatment of ovarian cancer (OC). However, the inevitable development of platinum and poly (adenosine diphosphate-ribose) polymerase inhibitor (PARPi) resistance is associated with poor outcomes, which becomes a major obstacle in the management of this disease. The present study developed "all-in-one" nanoparticles that contained the PARPi olaparib and gallium (Ga) (III) (olaparib-Ga) to effectively reverse PARPi resistance in platinum-resistant A2780-cis and SKOV3-cis OC cells and in SKOV3-cis tumor models. Notably, the olaparib-Ga suppressed SKOV3-cis tumor growth with negligible toxicity. Moreover, the suppression effect was more evident when combining olaparib-Ga with cisplatin or carboplatin, as evaluated in A2780-cis and SKOV3-cis cells. Mechanistically, the combined treatment induced DNA damage, which elicited the activation of ataxia telangiectasia mutated (ATM)/AMT- and Rad3-related (ATR) checkpoint kinase 1 (Chk1)/Chk2 signal transduction pathways. This led to the arrest of cell cycle progression at S and G₂/M phases, which eventually resulted in apoptosis and cell death due to unrepairable DNA damage. In addition, effective therapeutic responses to olaparib-Ga and cisplatin combination or olaparib-Ga and carboplatin combination were observed in SKOV3-cis tumor-bearing animal models. Altogether, the present findings demonstrate that olaparib-Ga has therapeutic implications in platinum-resistant OC cells, and the combination of olaparib-Ga with cisplatin or carboplatin may be promising for treating patients with OC who exhibit resistance to both PARPi and platinum.

Overcoming PARPi resistance: Preclinical and clinical evidence in ovarian cancer

Ovarian cancer is the fifth cause of cancer-related deaths in women with high grade serous carcinoma (HGSOC) representing the most common histological subtype. Approximately 50 % of HGSOC are characterized by deficiency in homologous recombination (HR), one of the main cellular pathways to repair DNA double strand breaks and one of the well-described mechanisms is the loss of function of the BRCA1 or BRCA2 genes. Inhibition of the poly-ADP-ribose polymerase (PARP) is synthetic lethal with HR deficiency and the use of PARP inhibitors (PARPi) has significantly improved the outcome of patients with HGSOC with a greater benefit in patients with BRCA1/2 deficient tumors. However, intrinsic or acquired resistance to PARPi inevitably occurs in most HGSOC patients. Distinct heterogeneous mechanisms underlying the resistance to PARPi have been described, including a decrease in intracellular drug levels due to upregulation of multidrug efflux pumps, loss of expression/inactivating mutations in the PARP1 protein, restoration of HR and the protection of the replicative fork. Deciphering the molecular mechanisms of resistance to PARPi is of paramount importance towards the development of new treatment strategies and/or novel pharmacological agents to overcome this chemoresistance and optimize the treatment regimen for individual HGSOC patients. The current review summarizes the mechanisms underlying the resistance to PARPi, the available preclinical and clinical data on new combination treatment strategies (with chemotherapy, anti-angiogenic agents and immune checkpoint inhibitors) as well as agents under investigation which target the DNA damage response.

Adaptive randomised controlled non-inferiority multicentre trial (the Ketodex Trial) on intranasal dexmedetomidine plus ketamine for procedural sedation in children: study protocol

INTRODUCTION

Up to 40% of orthopaedic injuries in children require a closed reduction, almost always necessitating procedural sedation. Intravenous ketamine is the most commonly used sedative agent. However, intravenous insertion is painful and can be technically difficult in children. We hypothesise that a combination of intranasal dexmedetomidine plus intranasal ketamine (Ketodex) will be non-inferior to intravenous ketamine for effective sedation in children undergoing a closed reduction.

METHODS AND ANALYSIS

This is a six-centre, four-arm, adaptive, randomised, blinded, controlled, non-inferiority trial. We will include children 4-17 years with a simple upper limb fracture or dislocation that requires sedation for a closed reduction. Participants will be randomised to receive either intranasal Ketodex (one of three dexmedetomidine and ketamine combinations) or intravenous ketamine. The primary outcome is adequate sedation as measured using the Paediatric Sedation State Scale. Secondary outcomes include length of stay, time to wakening and adverse effects. The results of both per protocol and intention-to-treat analyses will be reported for the primary outcome. All inferential analyses will be undertaken using a response-adaptive Bayesian design. Logistic regression will be used to model the dose-response relationship for the combinations of intranasal Ketodex. Using the Average Length Criterion for Bayesian sample size estimation, a survey-informed non-inferiority margin of 17.8% and priors from historical data, a sample size of 410 participants will be required. Simulations estimate a type II error rate of 0.08 and a type I error rate of 0.047.

ETHICS AND DISSEMINATION

Ethics approval was obtained from Clinical Trials Ontario for London Health Sciences Centre and McMaster Research Ethics Board. Other sites have yet to receive approval from their institutions. Informed consent will be obtained from guardians of all participants in addition to assent from participants. Study data will be submitted for publication regardless of results.

TRIAL REGISTRATION NUMBER

NCT0419525.

Total intravenous anaesthesia in ambulatory care

PURPOSE OF REVIEW

The purpose of this article is to review the use of total intravenous anaesthesia (TIVA) in ambulatory care.

RECENT FINDINGS

The number of ambulatory surgery cases is likely to increase in coming years. Recent meta-analyses suggest that TIVA offers decreased postoperative nausea and vomiting (PONV) and decreased pain scores in the postanaesthesia care unit (PACU) in day case/ambulatory surgery patients when compared with volatile anaesthesia. Particular improvements have also been shown in endoscopic nasal surgery in terms of decreased blood loss. TIVA consistently scores higher than volatile techniques in patient satisfaction surveys. Surveys of anesthetists suggest that TIVA is not in widespread use. This may be because of the perceived lack of training or confidence in the technique, therefore, recent internationally agreed guidelines aimed at formalizing its practice are welcome. There is also some recent evidence to suggest that intraoperative dexmedetomidine is superior to remifentanil with respect to postoperative pain and speed of recovery, and that intraoperative lignocaine infusion may reduce chronic pain incidence in breast surgery.

SUMMARY

Review of recent evidence of TIVA's use in ambulatory surgery and summary of new international guidelines on its use.

Intranasal Dexmedetomidine for Procedural Distress in Children: A Systematic Review

CONTEXT

Intranasal dexmedetomidine (IND) is an emerging agent for procedural distress in children.

OBJECTIVE

To explore the effectiveness of IND for procedural distress in children.

DATA SOURCES

We performed electronic searches of Medline (1946-2019), Embase (1980-2019), Google Scholar (2019), Cumulative Index to Nursing and Allied Health Literature (1981-2019), and Cochrane Central Register.

STUDY SELECTION

We included randomized trials of IND for procedures in children.

DATA EXTRACTION

Methodologic quality of evidence was evaluated by using the Cochrane Collaboration's risk of bias tool and the Grading of Recommendations Assessment, Development, and Evaluation system, respectively. The primary outcome was the proportion of participants with adequate sedation.

RESULTS

Among 19 trials (N = 2137), IND was superior to oral chloral hydrate (3 trials), oral midazolam (1 trial), intranasal midazolam (1 trial), and oral dexmedetomidine (1 trial). IND was equivalent to oral chloral hydrate (2 trials), intranasal midazolam (2 trials), and intranasal ketamine (3 trials). IND was inferior to oral ketamine and a combination of IND plus oral ketamine (1 trial). Higher doses of IND were superior to lower doses (4 trials). Adverse effects were reported in 67 of 727 (9.2%) participants in the IND versus 98 of 591 (16.6%) in the comparator group. There were no reports of adverse events requiring resuscitative measures.

LIMITATIONS

The adequacy of sedation was subjective, which possibly led to biased outcome reporting.

CONCLUSIONS

Given the methodologic limitations of included trials, IND is likely more effective at sedating children compared to oral chloral hydrate and oral midazolam. However, this must be weighed against the potential for adverse cardiovascular effects.

Virtual Reality Distraction during Endoscopic Urologic Surgery under Spinal Anesthesia: A Randomized Controlled Trial

Sedation protocols during spinal anesthesia often involve sedative drugs associated with complications. We investigated whether virtual reality (VR) distraction could be applied during endoscopic urologic surgery under spinal anesthesia and yield better satisfaction than pharmacologic sedation. VR distraction without sedative was compared with pharmacologic sedation using repeat doses of midazolam 1–2 mg every 30 min during urologic surgery under spinal anesthesia. We compared the satisfaction of patients, surgeons, and anesthesiologists, as rated on a 5-point prespecified verbal rating scale. Two surgeons and two anesthesiologists rated the scale and an overall score was reported after discussion. Thirty-seven patients were randomized to a VR group (n = 18) or a sedation group (n = 19). The anesthesiologist’s satisfaction score was significantly higher in the VR group than in the sedation group (median (interquartile range) 5 (5–5) vs. 4 (4–5), p = 0.005). The likelihood of both patients and anesthesiologists being extremely satisfied was significantly higher in the VR group than in the sedation group. Agreement between the scores for surgeons and those for anesthesiologists was very good (kappa = 0.874 and 0.944, respectively). The incidence of apnea was significantly lower in the VR group than in the sedation group (n = 1, 5.6% vs. n = 7, 36.8%, p = 0.042). The present findings suggest that VR distraction is better than drug sedation with midazolam in terms of patient’s and anesthesiologist’s satisfaction and avoiding the respiratory side effects of midazolam during endoscopic urologic surgery under spinal anesthesia.

Recovery time after oral and maxillofacial ambulatory surgery with dexmedetomidine: an observational study

OBJECTIVES

To evaluate the relationship between pharmacokinetic descriptors of dexmedetomidine (predicted area under the curve during the procedure, predicted plasma level at the end of the procedure, and duration of procedure) and sedation depth (proportion of time with bispectral index < 85 during the procedure) with recovery time after ambulatory procedures.

MATERIALS AND METHODS

Clinical observational study of patients undergoing oral and maxillofacial ambulatory surgery with dexmedetomidine as sole sedative agent. Patients received a loading dose of dexmedetomidine (0.25-1 μg kg^-1) followed by a maintenance infusion (0.2-1.4 μg kg^-1 h^-1) to keep a bispectral index < 85 until 5 min before the end of the procedure, and were transferred to a post-anesthesia care unit until criteria for discharge were met.

RESULTS

Data from 75 patients was analyzed. Sedation depth was directly associated with recovery time (Pearson correlation coefficient [r] = 0.26; p = 0.024). Around 7% of the variation in recovery time was explained by the proportion of time with bispectral index < 85. No association with procedure duration (r = 0.01; p = 0.9), predicted area under the curve (r = 0.1; p = 0.4), or predicted plasma level of dexmedetomidine at the end of the procedure (r = 0.12; p = 0.3) with recovery time was observed.

CONCLUSIONS

Sedation depth with dexmedetomidine could play a role in increasing recovery time after oral and maxillofacial ambulatory surgery. In our study, the pharmacokinetic descriptors of dexmedetomidine did not seem to influence recovery time.

CLINICAL RELEVANCE

Sedation depth with dexmedetomidine could play a role in increasing recovery time after ambulatory procedures.