A phase II/III, multicenter, safety, efficacy, and pharmacokinetic study of dexmedetomidine in preterm and term neonates

Dexmedetomidine for analgesia and sedation in newborn infants receiving mechanical ventilation

BACKGROUND

Dexmedetomidine is a selective alpha-2 agonist with minimal impact on the haemodynamic profile. It is thought to be safer than morphine or stronger opioids, which are drugs currently used for analgesia and sedation in newborn infants. Dexmedetomidine is increasingly being used in children and infants despite not being licenced for analgesia in this group.

OBJECTIVES

To determine the overall effectiveness and safety of dexmedetomidine for sedation and analgesia in newborn infants receiving mechanical ventilation compared with other non-opioids, opioids, or placebo.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and two trial registries in September 2023.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) and quasi-RCTs evaluating the effectiveness of dexmedetomidine compared with other non-opioids, opioids, or placebo for sedation and analgesia in neonates (aged under four weeks) requiring mechanical ventilation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were level of sedation and level of analgesia. Our secondary outcomes included days on mechanical ventilation, number of infants requiring additional medication for sedation or analgesia (or both), hypotension, neonatal mortality, and neurodevelopmental outcomes. We planned to use GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified no eligible studies for inclusion. We identified four ongoing studies, two of which appear to be eligible for inclusion; they will compare dexmedetomidine with fentanyl in newborn infants requiring surgery. We listed the other two studies as awaiting classification pending assessment of full reports. One study will compare dexmedetomidine with morphine in asphyxiated newborns undergoing hypothermia, and the other (mixed population, age up to three years) will evaluate dexmedetomidine versus ketamine plus dexmedetomidine for echocardiography. The planned sample size of the four studies ranges from 40 to 200 neonates. Data from these studies may provide some evidence for dexmedetomidine efficacy and safety.

AUTHORS' CONCLUSIONS

Despite the increasing use of dexmedetomidine, there is insufficient evidence supporting its routine use for analgesia and sedation in newborn infants on mechanical ventilation. Furthermore, data on dexmedetomidine safety are scarce, and there are no data available on its long-term effects. Future studies should address the efficacy, safety, and long-term effects of dexmedetomidine as a single drug therapy for sedation and analgesia in newborn infants.

Association of dexmedetomidine use with haemodynamics, postoperative recovery, and cost in paediatric anaesthesia: a hospital registry study

BACKGROUND

Dexmedetomidine utilisation in paediatric patients is increasing. We hypothesised that intraoperative use of dexmedetomidine in children is associated with longer postanaesthesia care unit length of stay, higher healthcare costs, and side-effects.

METHODS

We analysed data from paediatric patients (aged 0-12 yr) between 2016 and 2021 in the Bronx, NY, USA. We matched our cohort with the Healthcare Cost and Utilization Project-Kids' Inpatient Database (HCUP-KID).

RESULTS

Among 18 104 paediatric patients, intraoperative dexmedetomidine utilisation increased from 51.7% to 85.7% between 2016 and 2021 (P<0.001). Dexmedetomidine was dose-dependently associated with a longer postanaesthesia care unit length of stay (adjusted absolute difference [ADadj] 19.7 min; 95% confidence interval [CI]: 18.0-21.4 min; P<0.001, median length of stay of 122 vs 98 min). The association was magnified in children aged ≤2 yr undergoing short (≤60 min) ambulatory procedures (ADadj 33.3 min; 95% CI: 26.3-40.7 min; P<0.001; P-for-interaction <0.001). Dexmedetomidine was associated with higher total hospital costs of USD 1311 (95% CI: USD 835-1800), higher odds of intraoperative mean arterial blood pressure below 55 mm Hg (adjusted odds ratio [ORadj] 1.27; 95% CI: 1.16-1.39; P<0.001), and higher odds of heart rate below 100 beats min-1 (ORadj 1.32; 95% CI: 1.21-1.45; P<0.001), with no preventive effects on emergence delirium requiring postanaesthesia i.v. sedatives (ORadj 1.67; 95% CI: 1.04-2.68; P=0.034).

CONCLUSIONS

Intraoperative use of dexmedetomidine is associated with unwarranted haemodynamic effects, longer postanaesthesia care unit length of stay, and higher costs, without preventive effects on emergence delirium.

Efficacy and safety of dexmedetomidine for analgesia and sedation in neonates: a systematic review

Opioids and benzodiazepines have historically been employed for pain relief; however, they are associated with detrimental long-term neurodevelopmental consequences. Dexmedetomidine, a highly selective alpha-2-adrenoreceptor agonist, has piqued interest as a viable alternative for neonates, owing to its potential analgesic and neuroprotective attributes. We conducted a systematic review to assess the efficacy and safety of dexmedetomidine utilization in neonates. We conducted a comprehensive search of Ovid, MEDLINE, EMBASE, PubMed, Cochrane, and CINAHL, spanning from January 2010 to September 2022. Our review encompassed six studies involving 252 neonates. Overall, dexmedetomidine may be effective in achieving sedation and analgesia. Furthermore, it may reduce the need for adjunctive sedation or analgesia, shorten the time to extubation, decrease the duration of mechanical ventilation, and accelerate the attainment of full enteral feeds. Notably, no significant adverse effects associated with dexmedetomidine were reported. Nevertheless, additional well-designed studies to establish both the efficacy and safety of dexmedetomidine in neonatal care are needed.

Dexmedetomidine During Therapeutic Hypothermia: A Multicenter Quality Initiative

OBJECTIVES

Sedation is typically used during neonatal therapeutic hypothermia (TH). This report describes a quality improvement (QI) initiative with the aim of decreasing opioid exposure during TH by implementing dexmedetomidine as the primary sedative agent.

METHODS

This dual-center QI initiative used a multidisciplinary team to create a sedation algorithm for safe implementation of dexmedetomidine as first-line therapy during TH. The primary measure in this initiative was cumulative opioid exposure during TH; balancing measures included safety parameters, primarily the rate of dexmedetomidine discontinuation because of bradycardia. Baseline demographic and clinical data were collected retrospectively for the period before implementation and prospectively during the QI period. Data were analyzed using statistical process control charts to identify change over time.

RESULTS

One-hundred and fifty-four neonates in the 2-year pre-QI period were compared with 135 neonates in the 2 years after guideline implementation. Guideline compliance with dexmedetomidine initiation was 99% and compliance with initial dosing increased from 70% to 91% during the QI period. The cumulative dose of opioid during TH decreased by >90% by the end of the QI period. Dexmedetomidine was discontinued for transient bradycardia in 9.6% of the study population. No other adverse effects were observed.

CONCLUSIONS

Dexmedetomidine may be used as the primary sedative during neonatal TH with a low incidence of adverse effects. Clinical trials evaluating the impact of sedation during TH on neurologic outcomes are needed.

The Use of Dexmedetomidine in Preterm Infants: A Single Academic Center Experience

OBJECTIVE

Preterm newborns (PTNBs) often require sedation and analgesia. Dexmedetomidine (DEX) is used to provide sedation in extremely PTNBs, even though information on such use is limited. The objective of this research is to describe the use of DEX in these patients in a single academic center.

METHODS

This is a retrospective study of PTNBs receiving DEX from January 1, 2010, through December 31, 2018, at the Cleveland Clinic Children's Hospital, a tertiary academic center operating 2 Level III and 1 Level IV neonatal intensive care units (NICUs). Inclusion criteria were gestational age (GA) <36 weeks and receipt of DEX for >2 days. Adequacy of clinical response was based on achieving Neonatal Pain, Agitation and Sedation Scale (N-PASS) scores <3. Hypotension, bradycardia, and respiratory depression were recorded as the incidence as adverse events.

RESULTS

A total of 105 patients were included. The birth weight median was 870 g (IQR, 615-1507); the GA median was 26 weeks (IQR, 24-31). The duration of DEX infusion averaged 7 days. The DEX dose averaged 0.4 mcg/kg (IQR, 0.3-0.45). Bradycardia was observed in 35 patients (57%) weighting <1 kg and in 7 patients (18%) >1 kg (p < 0.01). There was no difference in the incidence of other adverse events between these groups. However, infants <1 kg required more pharmacologic interventions to maintain N-PASS score <3.

CONCLUSIONS

DEX was well tolerated overall and provided adequate sedation to PTNBs in this cohort. From this study, we recommend a starting dose of 0.2 to 0.4 mcg/kg/hr and titrating up hourly until adequate sedation is achieved.

Use of Dexmedetomidine and Opioids in Hospitalized Preterm Infants

Importance

Dexmedetomidine, an α2-adrenergic agonist, is not approved by the Food and Drug Administration for use in premature infants. However, the off-label use of dexmedetomidine in premature infants has increased 50-fold in the past decade. Currently, there are no large studies characterizing dexmedetomidine use in US neonatal intensive care units (NICUs) or comparing the use of dexmedetomidine vs opioids in infants.

Objectives

To describe dexmedetomidine use patterns in the NICU and examine the association between dexmedetomidine and opioid use in premature infants.

Design, Setting, and Participants

A multicenter, observational cohort study was conducted from November 11, 2022, to April 4, 2023. Participants were inborn infants born between 22 weeks, 0 days, and 36 weeks, 6 days, of gestation at 1 of 383 Pediatrix Medical Group NICUs across the US between calendar years 2010 and 2020.

Main Outcome and Measure

Exposure to medications of interest defined as total days of exposure, timing of use, and changes over time.

Results

A total of 395 122 infants were included in the analysis. Median gestational age was 34 (IQR, 32-35) weeks, and median birth weight was 2040 (IQR, 1606-2440) g. There were 384 infants (0.1% of total; 58.9% male) who received dexmedetomidine. Infants who received dexmedetomidine were born more immature, had lower birth weight, longer length of hospitalization, more opioid exposure, and more days of mechanical ventilation. Dexmedetomidine use increased from 0.003% in 2010 to 0.185% in 2020 (P < .001 for trend), while overall opioid exposure decreased from 8.5% in 2010 to 7.2% in 2020 (P < .001 for trend). The median postmenstrual age at first dexmedetomidine exposure was 31 (IQR, 27-36) weeks, and the median postnatal age at first dexmedetomidine exposure was 3 (IQR, 1-35) days. The median duration of dexmedetomidine receipt was 6 (IQR, 2-14) days.

Conclusion and Relevance

The findings of this multicenter cohort study of premature infants suggest that dexmedetomidine use increased significantly between 2010 and 2020, while overall opioid exposure decreased. Future studies are required to further examine the short- and long-term effects of dexmedetomidine in premature and critically ill infants.

Predicting Volume of Distribution in Neonates: Performance of Physiologically Based Pharmacokinetic Modelling

The volume of distribution at steady state (Vss) in neonates is still often estimated through isometric scaling from adult values, disregarding developmental changes beyond body weight. This study aimed to compare the accuracy of two physiologically based pharmacokinetic (PBPK) Vss prediction methods in neonates (Poulin & Theil with Berezhkovskiy correction (P&T+) and Rodgers & Rowland (R&R)) with isometrical scaling. PBPK models were developed for 24 drugs using in-vitro and in-silico data. Simulations were done in Simcyp (V22) using predefined populations. Clinical data from 86 studies in neonates (including preterms) were used for comparison, and accuracy was assessed using (absolute) average fold errors ((A)AFEs). Isometric scaling resulted in underestimated Vss values in neonates (AFE: 0.61), and both PBPK methods reduced the magnitude of underprediction (AFE: 0.82-0.83). The P&T+ method demonstrated superior overall accuracy compared to isometric scaling (AAFE of 1.68 and 1.77, respectively), while the R&R method exhibited lower overall accuracy (AAFE: 2.03). Drug characteristics (LogP and ionization type) and inclusion of preterm neonates did not significantly impact the magnitude of error associated with isometric scaling or PBPK modeling. These results highlight both the limitations and the applicability of PBPK methods for the prediction of Vss in the absence of clinical data.

The physiology, assessment, and treatment of neonatal pain

Studies have clearly shown that development of pain receptors starts as early as 20-weeks' gestation. Despite contrary belief, the human fetus develops a similar number of receptive pain fibers as seen in adults. These receptors' maturation is based on response to sensory stimuli received after birth which makes the NICU a critical place for developing central nervous system's pain perception. In practice, the assessment of pain relies mostly on bedside staff. In this review we will discuss the various developing features of pain pathways in the neonatal brain and the modification of pain perception secondary to various interactions immediately after birth. We also discuss the various tools utilized in the NICU for pain assessment that rely on physiological and behavioral patterns. Finally, we address the management of pain in the NICU by either pharmacological or non-pharmacological intervention while highlighting potential benefits, disadvantages, and situations where one may be preferred over another.

Cardioprotective Effects of Dexmedetomidine in an Oxidative-Stress In Vitro Model of Neonatal Rat Cardiomyocytes

Preterm birth is a risk factor for cardiometabolic disease. The preterm heart before terminal differentiation is in a phase that is crucial for the number and structure of cardiomyocytes in further development, with adverse effects of hypoxic and hyperoxic events. Pharmacological intervention could attenuate the negative effects of oxygen. Dexmedetomidine (DEX) is an α2-adrenoceptor agonist and has been mentioned in connection with cardio-protective benefits. In this study, H9c2 myocytes and primary fetal rat cardiomyocytes (NRCM) were cultured for 24 h under hypoxic condition (5% O₂), corresponding to fetal physioxia (pO₂ 32-45 mmHg), ambient oxygen (21% O₂, pO₂ ~150 mmHg), or hyperoxic conditions (80% O₂, pO₂ ~300 mmHg). Subsequently, the effects of DEX preconditioning (0.1 µM, 1 µM, 10 µM) were analyzed. Modulated oxygen tension reduced both proliferating cardiomyocytes and transcripts (CycD2). High-oxygen tension induced hypertrophy in H9c2 cells. Cell-death-associated transcripts for caspase-dependent apoptosis (Casp3/8) increased, whereas caspase-independent transcripts (AIF) increased in H9c2 cells and decreased in NRCMs. Autophagy-related mediators (Atg5/12) were induced in H9c2 under both oxygen conditions, whereas they were downregulated in NRCMs. DEX preconditioning protected H9c2 and NRCMs from oxidative stress through inhibition of transcription of the oxidative stress marker GCLC, and inhibited the transcription of both the redox-sensitive transcription factors Nrf2 under hyperoxia and Hif1α under hypoxia. In addition, DEX normalized the gene expression of Hippo-pathway mediators (YAP1, Tead1, Lats2, Cul7) that exhibited abnormalities due to differential oxygen tensions compared with normoxia, suggesting that DEX modulates the activation of the Hippo pathway. This, in the context of the protective impact of redox-sensitive factors, may provide a possible rationale for the cardio-protective effects of DEX in oxygen-modulated requirements on survival-promoting transcripts of immortalized and fetal cardiomyocytes.

Single-bolus dexmedetomidine in prevention of emergence delirium in pediatric ophthalmic surgeries: A randomized controlled trial

Purpose

Emergency delirium (ED), a common postoperative neurologic complication, causes behavioral disturbances leading to self-traumas and also has long-term adverse effects in children. Our aim was to investigate the efficacy of a single-bolus dose of dexmedetomidine in reducing the incidence of ED. Additionally, pain relief, number of patients who needed rescue analgesia, hemodynamic parameters, and adverse events were assessed.

Methods

One hundred and one patients were randomly allocated into two groups: 50 patients received 15 mL of dexmedetomidine 0.4 μg/kg (group D) and 51 patients received volume-matched normal saline (group C). Hemodynamic parameters such as heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were monitored regularly throughout the procedure. ED was assessed with Pediatric Anesthesia Emergence Delirium Scale (PAEDS), and pain was measured using the modified Objective Pain Score (MOPS).

Results

The incidences of ED and pain were higher in group C than group D (P < 0.0001 and P < 0.0001, respectively). Group D showed significant decrease in MOPS and PAEDS values at 5, 10, 15, and 20 min (P < 0.05), HR at 5 min (P < 0.0243), and SBP at 15 min (P < 0.0127). There was no significant difference in DBP between the two groups at any time point. The mean blood pressure (MBP) at 10 min was significantly less in group D than group C (P < 0.001).

Conclusion

Dexmedetomidine 0.4 μg/kg as a single bolus over 10 min immediately after intubation is effective for the prevention of ED and significantly reduces the need of rescue analgesia without compromising the hemodynamic parameters in children undergoing ophthalmic surgery.

Impact of dexmedetomidine in conjunction with a weaning protocol on post-surgical opioid use in a neonatal intensive care unit

STUDY OBJECTIVE

To describe the impact of protocol-driven dexmedetomidine (and clonidine) use on opioid exposure in post-surgical neonates.

DESIGN

Retrospective chart review.

SETTING

A Level III, surgical NICU.

PATIENTS

Surgical neonates who received clonidine or dexmedetomidine concomitantly with an opioid for sedation and/or analgesia post-operatively.

INTERVENTION

Implementation of a standardized sedation/analgesia weaning protocol.

MEASUREMENTS AND MAIN RESULTS

There were clinically, although not statistically, significant reductions in opioid wean duration (240 vs. 227 h, p = 0.82), total opioid duration (604 vs. 435 h, p = 0.23), and total opioid exposure (91 vs. 51 mg ME/kg, p = 0.13), and limited impact on NICU outcomes or pain/withdrawal scores with use of the protocol. Increases in use of medications in alignment with the protocol (e.g., scheduled acetaminophen and opioids weaned first) were noted.

CONCLUSIONS

We have been unable to demonstrate a reduction in opioid exposure with use of alpha-2 agonists alone; addition of a weaning protocol showed a reduction in opioid duration and exposure (although not statistically significant). At this point, dexmedetomidine and clonidine should not be introduced outside standardized protocols with scheduled acetaminophen post-operatively.

Dexmedetomidine: An Alternative to Pain Treatment in Neonatology

Infants might be exposed to pain during their admissions in the neonatal intensive care unit [NICU], both from their underlying conditions and several invasive procedures required during their stay. Considering the particularities of this population, recognition and adequate management of pain continues to be a challenge for neonatologists and investigators. Diverse therapies are available for treatment, including non-pharmacological pain management measures and pharmacological agents (sucrose, opioids, midazolam, acetaminophen, topical agents…) and research continues. In recent years one of the most promising drugs for analgesia has been dexmedetomidine, an alpha-2 adrenergic receptor agonist. It has shown a promising efficacy and safety profile as it produces anxiolysis, sedation and analgesia without respiratory depression. Moreover, studies have shown a neuroprotective role in animal models which could be beneficial to neonatal population, especially in preterm newborns. Side effects of this therapy are mainly cardiovascular, but in most studies published, those were not severe and did not require specific therapeutic measures for their resolution. The main objective of this article is to summarize the existing literature on neonatal pain management strategies available and review the efficacy of dexmedetomidine as a new therapy with increasing use in the NICU.

Dexmedetomidine versus fentanyl for sedation in extremely preterm infants

BACKGROUND

Few studies have compared the efficacy and complications of dexmedetomidine (DEX) and fentanyl (FEN) in extremely preterm infants.

METHODS

We conducted a single-institution, retrospective controlled before and after study of preterm infants before 28 weeks of gestation admitted between April 2010 and December 2018 to compare the complications and efficacy of DEX and FEN for preterm infants. Patients were administered FEN prior to 2015 and DEX after 2015 as the first-line sedative. A composite outcome of death during hospitalization and developmental quotient (DQ) < 70 at a corrected age of 3 years was compared as the primary outcome. Secondary outcomes including postmenstrual weeks at extubation, days of age when full enteral feeding was achieved and additional sedation by phenobarbital (PB) were compared.

RESULTS

Sixty-six infants were enrolled into the study. The only perinatal factor that differed between the FEN (n = 33) and DEX (n = 33) groups was weeks of gestation. The composite outcome of death and DQ < 70 at a corrected age of 3 years were not significantly different. Postmenstrual weeks at extubation did not significantly differ between groups after adjustment for weeks of gestation and being small for gestational age. On the other hand, full feeding was significantly prolonged by DEX (p = 0.031). Additional sedation was less common in the DEX group (p = 0.044).

CONCLUSION

The composite outcome of death and DQ < 70 at a corrected age of 3 years were not significantly different by DEX or FEN for primary sedation. Prospective randomized controlled trials should examine the long-term effects on development.

Analgesia, Sedation, and Anesthesia for Neonates With Cardiac Disease

Analgesia, sedation, and anesthesia are a continuum. Diagnostic and/or therapeutic procedures in newborns often require analgesia, sedation, and/or anesthesia. Newborns, in general, and, particularly, those with heart disease, have an increased risk of serious adverse events, including mortality under anesthesia. In this section, we discuss the assessment and management of pain and discomfort during interventions, review the doses and side effects of commonly used medications, and provide recommendations for their use in newborns with heart disease. For procedures requiring deeper levels of sedation and anesthesia, airway and hemodynamic support might be necessary. Although associations of long-term deleterious neurocognitive effects of anesthetic agents have received considerable attention in both scientific and lay press, causality is not established. Nonetheless, an early multimodal, multidisciplinary approach is beneficial for safe management before, during, and after interventional procedures and surgery to avoid problems of tolerance and delirium, which can contribute to long-term cognitive dysfunction.

Dexmedetomidine as a sole sedative for procedural sedation in preterm and neonate infants: A retrospective analysis

BACKGROUND

Many different sedation concepts for magnetic resonance imaging have been described for prematurely and term-born infants, ranging from "no sedation" to general anesthesia. Dexmedetomidine is an alpha-2 receptor agonist that is frequently used to sedate older children, because the anesthesiologist can easily adjust sedation depth, the patient maintains spontaneous breathing, and awakens rapidly afterwards.

AIMS

The present study evaluates whether dexmedetomidine could safely be used as the sole sedative for prematurely and term-born infants less than 60 weeks postconceptional age undergoing diagnostic procedures.

METHODS

We performed a retrospective monocentric analysis of n = 39 prematurely and term-born infants (<60 weeks postconceptional age or a body weight <5 kg) who were sedated with dexmedetomidine for an MRI at a German university hospital from August 2016 to November 2018.

RESULTS

Successful imaging was achieved in all cases. The median initial bolus of dexmedetomidine administered over 10 min was 1.39 μg kg^-1 body weight (range 0.34-3.64 μg kg^-1 ), followed with a continuous infusion at a median rate of 1.00 μg kg^-1  h^-1 (range 0.5-3.5 μg kg^-1  h^-1 ); however, 3 patients (7%) needed some additional sedation (ketamine or propofol). All patients, including 10 infants who had previously required respiratory support, underwent the procedure without any relevant desaturation or apnea. Bradycardia was observed in up to 15 out of 39 cases (38.5%), but only four (10.3% in total and 26.7% of bradycardia) required atropine.

CONCLUSIONS

These results indicate that dexmedetomidine can be safely used for procedural sedation in the high-risk cohort of prematurely and term-born infants less than 60 weeks postconceptional age. Apnea during procedural sedation and subsequent stay in the recovery room is avoided, but bradycardia remains a relevant risk that may require treatment.

The Impact of Dexmedetomidine Initiation on Cardiovascular Status and Oxygenation in Critically ill Neonates

Dexmedetomidine is being increasingly used as a primary or adjunctive sedative agent in neonates. There are a paucity of high-quality, high-resolution physiologic data during administration, despite significant potential cardiorespiratory effects. Term and preterm infants admitted between January 2018 and July 2020 were screened for dexmedetomidine exposure. Prospectively recorded vital signs (heart rate, oxygenation, arterial blood pressure) were cross-matched with pharmacy records to identify infants with data available 24 h before and 48 h after drug initiation. Vital sign data were processed via a standardized pipeline to (a) remove missing data, (b) obtain baseline averages of vital signs for 24 h preceding dexmedetomidine, and (c) calculate the hourly mean deviation from the baseline for the 48 h following initiation of dexmedetomidine. Infants were clustered by postmenstrual age (preterm ≤ 35 weeks; term > 35 weeks). 72 infants were identified with mean gestational age of 32 weeks and mean ± SD birth weight of 1976 ± 1341 g. Although both groups of infants experienced bradycardia, heart rate in term infants dropped faster and reached a nadir 5 beats per minute lower, before converging at a common deviation of - 10 beats per minute. No hypo- or hypertension was noted in either group. Unexpected instability of oxygenation occurred in a subset of preterm infants, requiring escalation of respiratory support. Administration of dexmedetomidine results in differential timing and magnitude of bradycardia in term and preterm infants, no major impact on blood pressure, and a surprising instability of oxygenation in preterm infants, requiring increased ventilatory support. Further investigation is warranted.

Evolving approaches in neonatal postoperative pain management

Neonates experience significant moderate and severe postoperative pain. Effective postoperative pain management in neonates is required to minimize acute and long-term effects of neonatal pain. Protecting the developing nervous system from persistent sensitization of pain pathways and developing primary hyperalgesia is essential. Opioids and acetaminophen are commonly analgesics used for pain control. Regional anesthesia provides adequate intraoperative and postoperative analgesia in neonates. It decreases exposure to opioids, reduces adverse drug effects, and facilitates early extubation. It suppresses the stress response and can prevent long-term behavioral responses to pain. The most common blocks performed in neonates are neuraxial blocks. Using ultrasound increased the number of peripheral nerve blocks performed in neonates. Recently, various peripheral nerve blocks (paravertebral, transverse abdominis plane, rectus sheath, quadratus lumborum, erector spinae plane blocks) were safely used. Many studies support analgesic efficacy but highlight neonates' unpredictability and variability of fascial blocks.

Frequencies, Modalities, Doses and Duration of Computerized Prescriptions for Sedative, Analgesic, Anesthetic and Paralytic Drugs in Neonates Requiring Intensive Care: A Prospective Pharmacoepidemiologic Cohort Study in 30 French NICUs From 2014 to 2020

Objectives: No consensus exists about the doses of analgesics, sedatives, anesthetics, and paralytics used in critically ill neonates. Large-scale, detailed pharmacoepidemiologic studies of prescription practices are a prerequisite to future research. This study aimed to describe the detailed prescriptions of these drug classes in neonates hospitalized in neonatal intensive care units (NICU) from computerized prescription records and to compare prescriptions by gestational age.

Materials and Methods: We included all neonates requiring intensive care in 30 French level III units from 2014 through 2020 with a computerized prescription for an analgesic, sedative, anesthetic, or paralytic agent. We described frequencies of prescription, methods of administration, concomitant drug prescriptions, and dosing regimen, and compared them across gestational ages.

Results: Among 65,555 neonates, 29,340 (44.8%) were prescribed at least one analgesic (acetaminophen in 37.2% and opioids in 17.8%), sedative (9.8%), anesthetic (8.5%), and/or paralytic agent (1%). Among preterm infants born before 28 weeks, 3,771/4,283 (88.0%) were prescribed at least one of these agents: 69.7% opioids, 41.2% sedatives, 32.5% anesthetics, and 5.8% paralytics. The most frequently prescribed agents were sufentanil (in 10.3% of neonates) and morphine (in 8.0% of neonates) for opioids, midazolam (9.3%) for sedatives, ketamine (5.7%) and propofol (3.3%) for anesthetics. In most neonates, opioids and sedatives were prescribed as continuous infusion, whereas anesthetics were prescribed as single doses. Opioids, sedatives and paralytics were mostly prescribed in association with another agent. Doses varied significantly by gestational age but within a limited range. Gestational age was inversely related to the frequency, cumulative dose and duration of prescriptions. For example, morphine prescriptions showed median (IQR) cumulative doses of 2601 (848–6750) vs. 934 (434–2679) µg/kg and median (IQR) durations of 7 (3–15) vs. 3 (2–5) days in infants born <28 vs. ≥ 37 weeks of gestation, respectively (p-value<0.001).

Conclusion: The prescriptions of analgesic, sedative, anesthetic, or paralytic agent were frequent and often combined in the NICU. Lower gestational age was associated with higher frequencies, longer durations and higher cumulative doses of these prescriptions. Dose-finding studies to determine individualized dosing regimens and studies on long-term neurodevelopmental outcome according to received cumulative doses are required.

Dexmedetomidine - An emerging option for sedation in neonatal patients

Dexmedetomidine is a sedative agent with limited dosing, safety, and efficacy information in the neonatal population. This comprehensive review describes the available evidence summarizing the use of dexmedetomidine in various neonatal populations. We identified 21 studies and 1 case report supporting the efficacy and short-term safety of DEX in neonates. Reported dosing ranges from 0.5-1.5 mcg/kg/h with or without loading doses. Clinically relevant adverse effects include bradycardia and hypotension. Future studies are needed to determine long-term safety and facilitate clinical applicability.

Pharmacokinetic Pharmacodynamic Modelling Contributions to Improve Paediatric Anaesthesia Practice

The use of pharmacokinetic-pharmacodynamic models has improved anaesthesia practice in children through a better understanding of dose-concentration-response relationships, developmental pharmacokinetic changes, quantification of drug interactions and insights into how covariates (e.g., age, size, organ dysfunction, pharmacogenomics) impact drug prescription. Simulation using information from these models has enabled the prediction and learning of beneficial and adverse effects and decision-making around clinical scenarios. Covariate information, including the use of allometric size scaling, age and consideration of fat mass, has reduced population parameter variability. The target concentration approach has rationalised dose calculation. Paediatric pharmacokinetic-pharmacodynamic insights have led to better drug delivery systems for total intravenous anaesthesia and an expectation about drug offset when delivery is stopped. Understanding concentration-dependent adverse effects have tempered dose regimens. Quantification of drug interactions has improved the understanding of the effects of drug combinations. Repurposed drugs (e.g., antiviral drugs used for COVID-19) within the community can have important effects on drugs used in paediatric anaesthesia, and the use of simulation educates about these drug vagaries.

Sedation and analgesia from prolonged pain and stress during mechanical ventilation in preterm infants: is dexmedetomidine an alternative to current practice?

Mechanical ventilation is an uncomfortable and potentially painful intervention. Opioids, such as morphine and fentanyl, are used for analgesia and sedation but there is uncertainty whether they reduce pain in mechanically ventilated infants. Moreover, there may be short-term and long-term adverse consequences such as respiratory depression leading to prolonged mechanical ventilation and detrimental long-term neurodevelopmental effects. Despite this, opioids are widely used, possibly due to a lack of alternatives.Dexmedetomidine, a highly selective alpha-2-adrenergic agonist with analgesic and sedative effects, currently approved for adults, has come into use in newborn infants. It provides analgesia and simulates natural sleep with maintenance of spontaneous breathing and upper airway tone. Although data on pharmacokinetics-pharmacodynamics in preterm infants are scant, observational studies report that using dexmedetomidine in conjunction with opioids/benzodiazepines or on its own can reduce the cumulative exposure to opioids/benzodiazepines. As it does not cause respiratory depression, dexmedetomidine could enable quicker weaning and extubation. Dexmedetomidine has also been suggested as an adjunct to therapeutic hypothermia in hypoxic ischaemic encephalopathy and others have used it during painful procedures and surgery. Dexmedetomidine infusion can cause bradycardia and hypotension although most report clinically insignificant effects.The increasing number of publications of observational studies and clinical use demonstrates that dexmedetomidine is being used in newborn infants but data on safety and efficacy are scant and not of high quality. Importantly, there are no data on long-term neurodevelopmental impact on preterm or term-born infants. The acceptance of dexmedetomidine in routine clinical practice must be preceded by clinical evidence. We need adequately powered and well-designed randomised controlled trials investigating whether dexmedetomidine alone or with opioids/benzodiazepines in infants on mechanical ventilation reduces the need for opioids/benzodiazepine and improves neurodevelopment at 24 months and later as compared with the use of opioids/benzodiazepines alone.

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.

Agreement of the Neonatal Pain, Agitation, and Sedation Scale (N-PASS) With NICU Nurses' Assessments

BACKGROUND

Objective assessment tools should standardize and reflect nurses' expert assessments. The Neonatal Pain, Agitation, and Sedation Scale (N-PASS) and the Neonatal Infant Pain Scale (NIPS) are valid measures of pain. The N-PASS also provides a sedation subscale.

PURPOSE

The objective of this study was to determine N-PASS clinical validity and utility by evaluating agreement of N-PASS scores with bedside nurses' assessments of pain/agitation and sedation in a 64-bed tertiary neonatal intensive care unit.

METHODS

Fifteen bedside nurses trained to use the N-PASS and the NIPS prospectively completed 202 pain/agitation and sedation assessments from a convenience sample of 88 infants, including chronically ventilated, medically fragile infants. N-PASS and NIPS scores were obtained simultaneously but independently of nurse investigators. Bedside nurses also made recommendations about infants' pain and sedation management.

RESULTS

There was moderate agreement between N-PASS pain scores and nurses' recommendations (κ= 0.52), very strong agreement between N-PASS sedation scores and nurses' recommendations (κ= 0.99), and very strong associations between N-PASS pain and NIPS scores (P< .001). Bedside nurse and independent investigator interrater reliability was good for N-PASS pain and NIPS scores (intraclass correlation coefficient [ICC] = 0.83, ICC = 0.85) and excellent for N-PASS sedation (ICC = 0.94). During 93% of assessments, bedside nurses reported that the N-PASS reflected the level of infant sedation well or very well.

IMPLICATIONS FOR PRACTICE AND RESEARCH

The N-PASS provides an easy-to-use, valid, and reliable objective measure of pain and sedation that reflects nurses' assessments. Additional studies using the N-PASS are needed to verify results and the influence of the N-PASS on pain and sedation management for medically fragile infants with chronic medical conditions.

Dexmedetomidine affects cerebral activity in preterm infants

The use of dexmedetomidine (DEX) has been extended in preterm newborns, but the effects on cerebral activity and their relationship with haemodynamic changes has not been studied.We retrospectively studied the effects of DEX administered to 10 preterm newborns, assessing amplitude-integrated EEG (aEEG) parameters, brain regional SO₂ (brSO₂), heart rate, non-invasive mean blood pressure (MBP), transcutaneous oxygen saturation (SpO₂), venous pCO2 and haemoglobin (Hb) values, in two 6-hour periods: one starting 6 hours before the beginning of DEX perfusion and the other 6 hours afterwards.DEX infusion led to brSO₂ decrease not associated to heart rate, MBP, SpO₂, Hb or pCO2 variation, which suggests that brSO₂ decrease could be related to local vasoconstriction. DEX infusion led to prolongation of interburst interval and reduction of cycling. Such effects, not been described so far, should be considered in the assessment of aEEG traces after DEX administration to avoid misinterpretations regarding patient's prognosis. More studies are needed to assess the safety of DEX use in the newborn.

Pharmacologic Analgesia and Sedation in Neonates

Chronic pain and agitation in neonatal life impact the developing brain. Oral sweet-tasting solutions should be used judiciously to mitigate behavioral responses to mild painful procedures, keeping in mind that the long-term impact is unknown. Rapidly acting opioids should be used as part of premedication cocktails for nonemergent endotracheal intubations. Continuous low-dose morphine or dexmedetomidine may be considered for preterm or term neonates exhibiting signs of stress during mechanical ventilation and therapeutic hypothermia, respectively. Further research is required regarding the pharmacokinetics, pharmacodynamics, safety, and efficacy of pharmacologic agents used to mitigate mild, moderate, and chronic pain and stress in neonates.

Effect of dexmedetomidine on heart rate in neonates with hypoxic ischemic encephalopathy undergoing therapeutic hypothermia

BACKGROUND

Sedation is recommended to optimize neuroprotection in neonates with hypoxic ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). Dexmedetomidine is an alternative agent to opioids, which are commonly used but have adverse effects. Both TH and dexmedetomidine can cause bradycardia. In this study, we describe our experience with dexmedetomidine and fentanyl in neonates undergoing TH for HIE, with a focus on heart rate (HR).

METHODS

We performed a retrospective chart review from 2011-2019 at a level IV NICU comparing sedation with dexmedetomidine (n = 14), fentanyl (n = 120), or both (n = 32) during TH for HIE. HR trends were compared based on sedation and gestational age. Neonates were included if they underwent TH and received sedation and were excluded if cooling was initiated past 24hours (h) from birth or if they required ECMO.

RESULTS

Of the 166 neonates included, 46 received dexmedetomidine, 14 as monotherapy and 32 in combination with fentanyl. Mean hourly HR from 12-36 h after birth was significantly lower for infants on dexmedetomidine versus fentanyl monotherapy (91±9 vs. 103±11 bpm, p < 0.002). Dexmedetomidine was decreased or discontinued in 22 (47.8%) neonates, most commonly due to inadequate sedation with a low HR. Lower gestational age was associated with higher HR but no significant difference in dexmedetomidine-related HR trends.

CONCLUSIONS

Despite an association with lower HR, dexmedetomidine may be successfully used in neonates with HIE undergoing TH. Implementation of a standardized protocol may facilitate dexmedetomidine titration in this population.

Intranasal Dexmedetomidine Accompanied by Cartoon Video Preoperation for Reducing Emergence Delirium in Children Undergoing Strabismus Surgery: A Prospective Randomized Trial

Background: After general anesthesia, many pediatric patients present with emergence delirium (ED). The aim of this study was to determine whether dexmedetomidine intranasal premedication accompanied by a cartoon video 30 min before general anesthesia would have an effect on reducing emergence delirium in preschool children.

Methods: One hundred and forty children aged 3–6 year undergoing elective strabismus surgery were randomly to be premedicated with 2 μg kg⁻¹ intranasal dexmedetomidine accompanied by the viewing of a cartoon video (Group DV) or without any premedication as usual (Group C). The primary outcome was the incidence of emergence delirium at the postanesthesia care unit (PACU), evaluated by the Pediatric Anesthesia Emergence Delirium (PAED) scale. The secondary outcomes included: the Modified Yale Preoperative Anxiety Scale (mYPAS) upon separation from parents; the Induction Compliance Checklist score (ICC); the PACU discharge time; the parental satisfaction score; the incidences of the side effects and the Post-Hospital Behavior Questionnaire (PHBQ) score during the first day after surgery.

Results: The incidence of emergence agitation (PAED score ≥ 10) was reduced in Group DV compared with Group C [8 (11.4%) vs. 24 (34.3%); P = 0.001]. None of the patients in the DV group experienced severe emergence agitation (PAED score ≥ 15), as compared with the C group (P = 0.006). The mYPAS score upon separation from parents (P < 0.001) and the incidence of poor coordination (ICC ≥ 4) during induction (P < 0.001) were significantly lower in Group DV than in Group C. In Group DV, the PACU discharge time was longer (P < 0.001), and the parental satisfaction score was higher (P < 0.001). However, during the first day after surgery, the PHBQ score was lower in Group DV compared with Group C (P = 0.001).

Conclusions: Premedication with 2 μg kg⁻¹ intranasal dexmedetomidine accompanied by cartoon video viewing can dramatically reduce emergence delirium in preschool children undergoing strabismus surgery, relieve preoperative anxiety and improve the parental satisfaction and the postoperative behavior changes during the first day after surgery.

Clinical Trial Registration: ChiCTR2000030678.

Reducing Benzodiazepine Exposure by Instituting a Guideline for Dexmedetomidine Usage in the NICU

BACKGROUND

Midazolam is a benzodiazepine sedative used in NICUs. Because benzodiazepine's effects include respiratory depression and potential detrimental developmental effects, minimizing exposure could benefit neonates. Dexmedetomidine is routinely used for sedation in older pediatric populations. We implemented a quality improvement initiative with the aim of decreasing midazolam infusions by 20% through use of dexmedetomidine.

METHODS

A multidisciplinary committee created a sedation guideline that included standardized dexmedetomidine dosing escalation and weaning. Baseline data collection occurred from January 2015 to February 2018, with intervention from March 2018 to December 2019. Percentage of sedation episodes with dexmedetomidine initiated was followed as a process measure. Outcomes measures were percentage of eligible infants receiving midazolam infusions and midazolam-free days per sedation episode. Bradycardia with dexmedetomidine, unplanned extubation rates, and morphine dosage were monitored as balancing measures.

RESULTS

Our study included 434 episodes of sedation in 386 patients. Dexmedetomidine initiation increased from 18% to 49%. The intervention was associated with a significant reduction in midazolam initiation by 30%, from 95% to 65%, with special cause variation on statistical process control chart analysis. Midazolam-free days per sedation episode increased from 0.3 to 2.2 days, and patients receiving dexmedetomidine had lower midazolam doses (1.3 mg/kg per day versus 2.2 mg/kg per day, P = 5.97 × 10-04). Bradycardia requiring discontinuation of dexmedetomidine, unplanned extubation rates, and morphine doses were unchanged.

CONCLUSIONS

Implementation of a quality improvement initiative was successful in reducing the percentage of patients receiving midazolam infusions and increased midazolam-free days per sedation episode, revealing an overall reduction in benzodiazepine exposure while maintaining adequate sedation.

Age-Specific Dose Regimens of Dexmedetomidine for Pediatric Patients in Intensive Care Following Elective Surgery: A Phase 3, Multicenter, Open-Label Clinical Trial in Japan

OBJECTIVES

To demonstrate the efficacy, safety, and pharmacokinetics of dexmedetomidine as a potential sedative for pediatric surgery patients in the ICU.

DESIGN

Phase 3, multicenter, open-label study.

SETTING

This study included 61 patients at 13 tertiary hospitals in Japan.

PATIENTS

Pediatric patients (≥ 45 wk corrected gestational age to < 17 yr) undergoing intensive care treatment with mechanical ventilation requiring greater than 6 hours estimated duration of sedation following elective cardiac surgery.

INTERVENTIONS

Dexmedetomidine was IV administered without a loading dose at age-specific dose regimens 0.2-1.4 (< 6 yr) and 0.2-1.0 µg/kg/hr (≥ 6 yr). The primary endpoint was the percentage of patients who did not require a rescue sedative (midazolam) infusion during mechanical ventilation or for the first 24 hours of a greater than 24 hours ventilation following the commencement of dexmedetomidine administration.

MEASUREMENTS AND MAIN RESULTS

Overall, 47 of the 61 patients (77.0%) did not require rescue midazolam. Adverse events were reported in 53 patients (86.9%). Frequently observed adverse events were hypotension (47.5%), bradycardia (31.1%), and respiratory depression (26.2%). Most of these adverse events were mild, a few moderate, and none severe. Although serious adverse events occurred in four patients, including one cardiac tamponade resulting in the withdrawal of dexmedetomidine, none of the adverse events resulted in mortality or were directly related to dexmedetomidine. The plasma dexmedetomidine concentration generally reached the target concentration of 0.3-1.25 ng/mL at 1-2 hours prior to completion of administration or immediately prior to the commencement of tapering.

CONCLUSIONS

The age-specific dose regimens of dexmedetomidine without an initial loading dose achieved an adequate sedation level during mechanical ventilation and caused no clinically significant adverse events in the intensive care pediatric patients. These effects were achieved within the therapeutic range of dexmedetomidine plasma concentration and were accompanied by minimal effects on hemodynamics and respiration.

Gabapentin in Infants: Critical Evaluation of a Novel Sedative/Analgesic Medication

Chronic pain and agitation can complicate the clinical course of critically ill infants. Randomized controlled trials of analgesia and sedation in neonatal intensive care have focused on relatively short durations of exposure. To date, clinicians have few options to treat chronic visceral pain and hyperalgesia. Gabapentin has emerged as a common therapy for a diverse group of pain syndromes and neurologic conditions in adults. In neonates, case reports and series describe the successful treatment of visceral hyperalgesia arising from gastrointestinal insults with or without concomitant neurologic morbidities. Additionally, a case report and series describe the utility of gabapentin for neonatal abstinence syndrome refractory to standard pharmacotherapy. The adverse effect profile of gabapentin, most notably bradycardia and sedation, compares favorably to alternative analgesics and sedatives. However, the long-term impacts of prolonged gabapentin therapy have not been studied. Therefore, candidates for therapy must be selected carefully, and response must be assessed objectively. Future studies must assess the short-term and long-term benefits and risks of gabapentin compared to standard therapies for chronic pain and agitation in infants and refractory neonatal abstinence syndrome.

Sedoanalgesia in neonatal units

Pain recognition and management continues to be a challenge for health professionals in Neonatal Intensive Care Units. Many of the patients are routinely exposed to repeated painful experiences with demonstrated short- and long-term consequences. Preterm babies are a vulnerable high-risk population. Despite international recommendations, pain remains poorly assessed and managed in many Neonatal Intensive Care Units. Due to there being no general protocol, there is significant variability as regards the guidelines for the approach and treatment of pain between the different Neonatal Intensive Care Units. The objective of this article is to review and assess the general principles of pain in the initial stages of development, its recognition through the use of standardised scales. It also includes its prevention and management with the combination of pharmacological and non-pharmacological measures, as well as to establish recommendations that help alleviate pain in daily clinical practice by optimising pain and stress control in the Neonatal Intensive Care Units.

Why do We Use the Concepts of Adult Anesthesia Pharmacology in Developing Brains? Will It Have an Impact on Outcomes? Challenges in Neuromonitoring and Pharmacology in Pediatric Anesthesia

BACKGROUND

Pediatric sedation and anesthesia techniques have plenty of difficulties and challenges. Data on the pharmacologic, electroencephalographic, and neurologic response to anesthesia at different brain development times are only partially known. New data in neuroscience, pharmacology, and intraoperative neuromonitoring will impact changing concepts and clinical practice. In this article, we develop a conversation to guide the debate and search for a view more attuned to the updated knowledge in neurodevelopment, electroencephalography, and clinical pharmacology for the anesthesiologic practice in the pediatric population.

Emerging therapies and management for neonatal encephalopathy-controversies and current approaches

Neonatal encephalopathy (NE) continues to have a major impact on newborn survival and neurodevelopmental outcomes worldwide. In high-income settings, therapeutic hypothermia is the only established standard treatment for neonates with moderate-to-severe NE, with compelling evidence that cooling reduces mortality and major neurodevelopmental impairment in survivors. Despite therapeutic hypothermia, a significant proportion of cooled infants continue to suffer long-term disability from brain injury. Innovative therapies offer the possibility of further improving neurodevelopmental outcomes by working synergistically with therapeutic hypothermia to decrease hypoxia-ischemia-induced excitotoxicity, prevent progression to secondary energy failure, and in some cases, promote neuroregeneration in the developing neonatal brain. This review discusses emerging NE therapies currently under investigation, offers insight into controversies surrounding various approaches to clinical care during therapeutic hypothermia, and identifies ongoing knowledge deficits that hinder attainment of optimal outcomes for neonates with NE.

Markedly long pause due to sinus arrest during dexmedetomidine use and nasal continuous positive airway pressure in two infants with respiratory syncytial virus infection

Nasal respiratory support for infants with respiratory distress caused by respiratory syncytial (RS) virus infection sometimes requires appropriate sedation. Dexmedetomidine can be an alternative sedative because of its advantage of less frequent respiratory suppression. We report the cases of twin infants with RS virus infection who showed unreported long pauses (4 and 10 s) due to sinus arrest while receiving dexmedetomidine. After termination of dexmedetomidine administration, the long pause of >2 s was no longer observed in both cases. RS virus infection may inhibit the conduction system and sometimes induce bradyarrhythmia. Cardiac and sinus arrests are reported as complications of dexmedetomidine administration. Thus, because dexmedetomidine administration and RS virus infection may additively or synergistically inhibit the conduction system, the use of dexmedetomidine in infantile RS infection should be carefully considered. If sedation is unavoidable, other drugs should be used first. An evidence-based safe regimen for sedation in infants with RS infection should be established in the near future. <Learning objective: Dexmedetomidine use as a sedative should be carefully considered in infants with respiratory syncytial (RS) infection because dexmedetomidine administration and RS virus infection may additively or synergistically inhibit the conduction system. If sedation is unavoidable, other drugs should be used first.>.

[Pediatric pain treatment and prevention for hospitalized children]

INTRODUCTION

Prevention and treatment of pain in pediatric patients compared with adults is often not only inadequate but also less often implemented the younger the children are. Children 0 to 17 years are a vulnerable population.

OBJECTIVES

To address the prevention and treatment of acute and chronic pain in children, including pain caused by needles, with recommended analgesic starting doses.

METHODS

This Clinical Update elaborates on the 2019 IASP Global Year Against Pain in the Vulnerable "Factsheet Pain in Children: Management" and reviews best evidence and practice.

RESULTS

Multimodal analgesia may include pharmacology (eg, basic analgesics, opioids, and adjuvant analgesia), regional anesthesia, rehabilitation, psychological approaches, spirituality, and integrative modalities, which act synergistically for more effective acute pediatric pain control with fewer side effects than any single analgesic or modality. For chronic pain, an interdisciplinary rehabilitative approach, including physical therapy, psychological treatment, integrative mind-body techniques, and normalizing life, has been shown most effective. For elective needle procedures, such as blood draws, intravenous access, injections, or vaccination, overwhelming evidence now mandates that a bundle of 4 modalities to eliminate or decrease pain should be offered to every child every time: (1) topical anesthesia, eg, lidocaine 4% cream, (2) comfort positioning, eg, skin-to-skin contact for infants, not restraining children, (3) sucrose or breastfeeding for infants, and (4) age-appropriate distraction. A deferral process (Plan B) may include nitrous gas analgesia and sedation.

CONCLUSION

Failure to implement evidence-based pain prevention and treatment for children in medical facilities is now considered inadmissible and poor standard of care.

Neonatal Pain, Agitation, and Sedation Scale's use, reliability, and validity: a systematic review

The Neonatal Pain, Agitation, and Sedation Scale (N-PASS) is recommended by the American Academy of Pediatrics to measure neonatal pain and sedation. However, little is known regarding its reliability and validity for diverse neonatal subpopulations. Twenty-nine studies were included in our review, demonstrating broad application of N-PASS and good or excellent reliability and validity for various neonatal subpopulations. Our systematic review found N-PASS to be valid and reliable for many but not all neonatal subpopulations. There is a lack of support for N-PASS reliability and validity for measuring prolonged pain and sedation in nonmechanically ventilated infants and for acute pain in postoperative infants in any gestational age category. Overall, N-PASS is a psychometrically sound and pragmatic instrument evaluating pain and sedation for most neonatal populations. Future research using N-PASS is encouraged to evaluate and report its validity and reliability, especially for neonatal subpopulations not included in this review.

A Universal Pharmacokinetic Model for Dexmedetomidine in Children and Adults

A universal pharmacokinetic model was developed from pooled paediatric and adult data (40.6 postmenstrual weeks, 70.8 years, 3.1-152 kg). A three-compartment pharmacokinetic model with first-order elimination was superior to a two-compartment model to describe these pooled dexmedetomidine data. Population parameter estimates (population parameter variability%) were clearance (CL) 0.9 L/min/70 kg (36); intercompartmental clearances (Q2) 1.68 L/min/70 kg (63); Q3 0.62 L/min/70 kg (90); volume of distribution in the central compartment (V1) 25.2 L/70 kg (103.9); rapidly equilibrating peripheral compartment (V2) 34.4 L/70 kg (41.8); slow equilibrating peripheral compartment (V3) 65.4 L/70 kg (62). Obesity was best described by fat-free mass for clearances and normal fat mass for volumes with a factor for fat mass (FfatV) of 0.293. Models describing dexmedetomidine pharmacokinetics in adults can be applied to children by accounting for size (allometry) and age (maturation). This universal dexmedetomidine model is applicable to a broad range of ages and weights: neonates through to obese adults. Lean body weight is a better size descriptor for dexmedetomidine clearance than total body weight. This parameter set could be programmed into target-controlled infusion pumps for use in a broad population.

Dexmedetomidine: What's New for Pediatrics? A Narrative Review

Over the past few years, despite the lack of approved pediatric labelling, dexmedetomidine’s (DEX) use has become more prevalent in pediatric clinical practice as well as in research trials. Its respiratory-sparing effects and bioavailability by various routes are only some of the valued features of DEX. In recent years the potential organ-protective effects of DEX, with the possibility for preserving neurocognitive function, has put it in the forefront of clinical and bench research. This comprehensive review focused on the pediatric literature but presents relevant, supporting adult and animal studies in order to detail the recent growing body of literature around the pharmacology, end-organ effects, organ-protective effects, alternative routes of administration, synergetic effects, and clinical applications, with considerations for the future.

Opioids and alpha-2-agonists for analgesia and sedation in newborn infants: protocol of a systematic review

BACKGROUND

Hospitalized newborn infants may require analgesia and sedation either for the management of procedural pain, during or after surgery, and other painful conditions. The benefits and harms of opioids administered at different doses and routes of administration have been reported in numerous trials and systematic reviews. The use of alpha-2-agonists such as clonidine and dexmedetomidine in newborn infants is more recent, and they might be prescribed to reduce the total amount of opioids which are thought to have more side effects. Moreover, alpha-2-agonists might play an important role in the management of agitation and discomfort.

METHODS

We will conduct a systematic review and meta-analysis on the use of opioids, alpha-2-agonists, or the combination of both drugs. We will include randomized controlled trials to assess benefits and harms and observational studies to assess adverse events and pharmacokinetics; preterm and term infants; studies on any opioids or alpha-2-agonists administered for any indication and by any route except spinal, intraosseous, or administration for nerve blocks and wound infusions. The use of opioids or alpha-2-agonists will be compared to no intervention; placebo with normal saline or other non-sedative, non-analgesic drug; control with oral sugar solution or non-pharmacological intervention; same drug of different dose or route; or a different drug (not limiting to opioids and alpha-2-agonists) or combinations of such drugs. The primary outcomes for this review will be all-cause mortality during initial hospitalization and hypotension requiring medical therapy. We will conduct a search in the following databases: The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, Embase, and CINAHL. Two review authors will independently screen records for inclusion, undertake data abstraction using a data extraction form and assess the risk of bias of all included trials using the Cochrane "Risk of bias" tool.

DISCUSSION

This systematic review will summarize and update our knowledge about neonatal analgesia and sedation including pharmacokinetics/pharmacodynamics, and provide a platform for developing evidence-based guidelines that we can immediately apply to our clinical practice.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2020 CRD42020170852.

An assessment of the impact of dexmedetomidine on opioid use in a neonatal intensive care unit

OBJECTIVE

To evaluate the impact of dexmedetomidine on opioid use in neonates.

METHODS

A retrospective chart review of neonates that received dexmedetomidine compared to matched historical controls in a surgical tertiary NICU. The primary endpoint was overall opioid exposure. Secondary endpoints included the duration of regular opioid use, duration of opioid wean, duration of mechanical ventilation, and time to achieve full enteral feeds.

RESULTS

There were no statistically significant differences in opioid exposure (60.3 vs 42.6 mcg ME/kg, p = .25), duration (583 vs 340 h, p = .07), or wean duration (261 vs 147 h, p = .12) between the two cohorts. In fact, these parameters showed clinically, if not statistically, significant increases in the dexmedetomidine cohort. Opioid exposure per day, length of NICU stay, duration of mechanical ventilation, and days to full enteral feeds did not differ between cohorts.

CONCLUSION

This retrospective cohort study did not show reduced opioid exposure in surgical neonates receiving dexmedetomidine, which is in contrast to other literature. It highlights the limitations of using a medication without appropriate guidance and assessment tools to support its use.

Pain Scales in Neonates Receiving Mechanical Ventilation in Neonatal Intensive Care Units - Systematic Review

INTRODUCTION

Recently, interest in the problem of proper prevention and monitoring of pain, especially acute, has been increasing in relation to various age groups. Greater awareness of the problem prompts discussion about the purpose of analgesia in newborns treated with mechanical ventilation.

AIM

The purpose of the systematic review was to analyze current research on the use of pain scales in newborns treated with mechanical ventilation in the Neonatal Intensive Care Unit.

METHODS

Medline databases: PubMed, OVID, EBSCO, Web of Science and Cochrane Library were traced using the appropriate keywords. The search was limited to studies in English. The review took into account the years 2006-2019. Considering the criteria, 12 articles were included in further analysis, to which full access was obtained.

RESULTS

The analyzed scientific research showed differences in beliefs about the validity and credibility of the scales used. Researchers indicated that staff with practical experience in using scales in their daily practice was very skeptical of the results obtained on their basis.

CONCLUSION

Based on this review, no explicit evidence can be obtained to support the use of one proper scale in pain assessment. It can be inferred that the COMFORT and N-PASS scales are effective for pain assessment and for determining the need for analgesics in mechanically ventilated neonates. These scales may be equally effective in assessing chronic pain, especially in mechanically ventilated children. On the other hand, the PIPP and CRIES scales are most commonly recommended for assessing acute and postoperative pain.

Pharmacokinetics and Sedative Effects of Intranasal Dexmedetomidine in Ambulatory Pediatric Patients

BACKGROUND

Our aim was to characterize the pharmacokinetics and sedative effects of intranasally (IN) administered dexmedetomidine used as an adjuvant in pediatric patients scheduled for magnetic resonance imaging (MRI) requiring sedation.

METHODS

This was an open-label, single-period study without randomization. Pediatric patients from 5 months to 11 years of age scheduled for MRI and receiving IN dexmedetomidine for premedication as part of their care were included in this clinical trial. Single doses of 2-3 µg·kg of dexmedetomidine were applied IN approximately 1 hour before MRI. Five or 6 venous blood samples were collected over 4 hours for dexmedetomidine concentration analysis. Sedation was monitored with Comfort-B scores, and vital signs were recorded. Pharmacokinetic variables were calculated with noncompartmental methods and compared between 3 age groups (between 1 and 24 months, from 24 months to 6 years, and over 6-11 years).

RESULTS

We evaluated 187 consecutive patients for suitability, of which 132 were excluded. Remaining 55 patients were recruited, of which 5 were excluded before the analysis. Data from 50 patients were analyzed. The average (standard deviation [SD]) dose-corrected peak plasma concentration (Cmax) was 0.011 liter (0.0051), and the median (interquartile range [IQR]) time to reach peak concentration (tmax) was 37 minutes (30-45 minutes). There was negative correlation with Cmax versus age (r = -0.58; 95% confidence interval [CI], -0.74 to -0.37; P < .001), but not with tmax (r = -0.14; 95% CI, 0.14-0.39; P = .35). Dose-corrected areas under the concentration-time curve were negatively correlated with age (r = -0.53; 95% CI, 0.70 to -0.29; P < .001). Median (IQR) maximal reduction in Comfort-B sedation scores was 8 (6-9), which was achieved 45 minutes (40-48 minutes) after dosing. Median (IQR) decrease in heart rate was 15% (9%-23%) from the baseline.

CONCLUSIONS

Dexmedetomidine is relatively rapidly absorbed after IN administration and provides clinically meaningful but short-lasting sedation in pediatric patients.

Dexmedetomidine Pharmacokinetics in Neonates with Hypoxic-Ischemic Encephalopathy Receiving Hypothermia

Dexmedetomidine is a promising sedative and analgesic for newborns with hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). Pharmacokinetics and safety of dexmedetomidine were evaluated in a phase I, single-center, open-label study to inform future trial strategies. We recruited 7 neonates ≥36 weeks' gestational age diagnosed with moderate-to-severe HIE, who received a continuous dexmedetomidine infusion during TH and the 6 h rewarming period. Time course of plasma dexmedetomidine concentration was characterized by serial blood sampling during and after the 64.8 ± 6.9 hours of infusion. Noncompartmental analysis yielded descriptive pharmacokinetic estimates: plasma clearance of 0.760 ± 0.155 L/h/kg, steady-state distribution volume of 5.22 ± 2.62 L/kg, and mean residence time of 6.84 ± 3.20 h. Naive pooled and population analyses according to a one-compartment model provided similar estimates of clearance and distribution volume. Overall, clearance was either comparable or lower, distribution volume was larger, and mean residence time or elimination half-life was longer in cooled newborns with HIE compared to corresponding estimates previously reported for uncooled (normothermic) newborns without HIE at comparable gestational and postmenstrual ages. As a result, plasma concentrations in cooled newborns with HIE rose more slowly in the initial hours of infusion compared to predicted concentration-time profiles based on reported pharmacokinetic parameters in normothermic newborns without HIE, while similar steady-state levels were achieved. No acute adverse events were associated with dexmedetomidine treatment. While dexmedetomidine appeared safe for neonates with HIE during TH at infusion doses up to 0.4 μg/kg/h, a loading dose strategy may be needed to overcome the initial lag in rise of plasma dexmedetomidine concentration.

Effects of Dexmedetomidine on Blood Glucose and Serum Potassium Levels in Children Undergoing General Anesthesia: A Secondary Analysis of Safety Endpoints During a Randomized Controlled Trial

BACKGROUND

Dexmedetomidine is a highly selective α2-adrenergic agonist, which is increasingly used in pediatric anesthesia and intensive care. Potential adverse effects that have not been rigorously evaluated in children include its effects on blood glucose and serum potassium concentrations, which are relevant due to the associations of derangements of both parameters with undesired outcomes. We investigated the effects of 3 different doses of dexmedetomidine on these outcomes in a randomized controlled trial in children undergoing elective surgery.

METHODS

Sixty-four American Society of Anesthesiologists I-II children were randomized to receive either dexmedetomidine 0.25 µg/kg, dexmedetomidine 0.5 µg/kg, dexmedetomidine 0.75 µg/kg, or 0 µg/kg (control), as a bolus administered over 60 seconds after induction of anesthesia. Changes in plasma glucose and serum potassium concentrations were measured in venous blood sampled before and at 15 and 30 minutes after study drug administration. Data were plotted within and between groups and analyzed using a constrained longitudinal data approach.

RESULTS

Forty-nine children completed the study. Mean glucose levels at 15 and 30 minutes were elevated with estimated changes from baseline of 0.37 mmol/L (95% CI, 0.29-0.45 mmol/L) and 0.05 mmol/L (95% CI, 0.00-0.10 mmol/L), respectively. At 15 minutes, there was a linear dose-response relationship (1.07 mmol/L/μg/kg [95% CI, 0.57-1.58 mmol/L/μg/kg]), but there was no appreciable effect of dexmedetomidine at 30 minutes (0.15 mmol/L/μg/kg [95% CI, -0.40 to 0.70 mmol/L/μg/kg]). Potassium levels were depressed relative to baseline, with a mean difference at 15 minutes of -0.20 mEq/L (95% CI, -0.28 to -0.12 mEq/L) and at 30 minutes of -0.12 mEq/L (95% CI, -0.15 to -0.08 mEq/L), but there was no appreciable effect of dexmedetomidine at either time.

CONCLUSIONS

Small elevations in glucose and decreases in potassium were observed after induction of anesthesia in children. The elevation in glucose at 15 minutes depended on the dose of dexmedetomidine administered. These preliminary data warrant further investigation.

The influence of pain, agitation, and their management on the immature brain

Preterm infants are exposed to frequent painful procedures and agitating stimuli over the many weeks of their hospitalization in the neonatal intensive care unit (NICU). The adverse neurobiological impact of pain and stress in the preterm infant has been well documented, including neuroimaging and neurobehavioral outcomes. Although many tools have been validated to assess acute pain, few methods are available to assess chronic pain or agitation (a clinical manifestation of neonatal stress). Both nonpharmacologic and pharmacologic approaches are used to reduce the negative impact of pain and agitation in the preterm infant, with concerns emerging over the adverse effects of analgesia and sedatives. Considering benefits and risks of available treatments, units must develop a stepwise algorithm to prevent, assess, and treat pain. Nonpharmacologic interventions should be consistently utilized prior to mild to moderately painful procedures. Sucrose may be utilized judiciously as an adjunctive therapy for minor painful procedures. Rapidly acting opioids (fentanyl or remifentanil) form the backbone of analgesia for moderately painful procedures. Chronic sedation during invasive mechanical ventilation represents an ongoing challenge; appropriate containment and an optimal environment should be standard; when indicated, low-dose morphine infusion may be utilized cautiously and dexmedetomidine infusion may be considered as an emerging adjunct.