Efficacy and safety of dexmedetomidine in maintaining hemodynamic stability in pediatric cardiac surgery: a systematic review and meta-analysis

Effectiveness of Dexmedetomidine as Myocardial Protector in Children With Classic Tetralogy of Fallot Having Corrective Surgery: A Randomized Controlled Trial

OBJECTIVES

Efficacy of dexmedetomidine (DEX) as a cardioprotective agent in Indonesian children undergoing classic tetralogy of Fallot (TOF) repair with cardiopulmonary bypass (CPB).

DESIGN

A prospective, parallel trial using block randomization along with double-blinded preparation of treatment agents by other parties.

SETTING

National Cardiovascular Center Harapan Kita, Indonesia.

PARTICIPANTS

Sixty-six children with classic TOF scheduled for corrective surgery. No children were excluded. All patients had fulfilled the criteria for analysis.

INTERVENTIONS

A total of 0.5 µg/kg bolus of DEX was added to the CPB priming solution, followed by 0.25 µg/kg/h maintenance during bypass. The placebo group used normal saline. Follow-ups were up to 30 days.

MEASUREMENTS AND MAIN RESULTS

Troponin I was lower in the DEX group at 6 hours (30.48 ± 19.33 v 42.73 ± 27.16, p = 0.039) and 24 hours after CPB (8.89 ± 5.42 v 14.04 ± 11.17, p = 0.02). Within a similar timeframe, DEX successfully lowered interleukin-6 (p = 0.03; p = 0.035, respectively). Lactate was lower in the Dex group at 1, 6, and 24 hours after CPB (p < 0.01; p = 0.048; p = 0.035; respectively). Dexmedetomidine increased cardiac output and index from 6 hours after bypass, but vice versa in systemic vascular resistance. Reduction of vasoactive inotropic score was seen during intensive care unit monitoring in the Dex group (p = 0.049). Nevertheless, DEX did not significantly affect the length of ventilation (p = 0.313), intensive care unit stay (p = 0.087), and mortality (p > 0.99).

CONCLUSIONS

Dexmedetomidine during CPB is an effective cardioprotective agent in TOF children having surgery. Postoperative mortality was comparable across groups.

Perioperative management of primary classic bladder exstrophy: A single institutional pathway to success

PURPOSE

Appropriate perioperative management is crucial in patients undergoing classic bladder exstrophy closure (CBE). Therefore, the authors sought to review their intra and postoperative management of patients with CBE undergoing primary closure and examine the impact of this pathway on patient outcomes.

METHOD

A prospectively maintained institutional approved exstrophy-epispadias complex database was reviewed for patients with CBE who had undergone primary closure between 2016 and 2022 and whose closure was performed within one year of age. Electronic medical records for eligible patients were retrospectively reviewed to examine patient demographics, use of pelvic osteotomy, immobilization status, pediatric intensive care unit (PICU) admission and management, perioperative analgesia and sedation, nutritional support, drainage tubes, blood transfusions, antibiotic coverage, hospital length of stay, postoperative complications, and closure failure.

RESULTS

A total of 25 patients were identified, 22 with CBE and 3 with variant CBE. Closure was performed at a median age of 84 days with patients ranging in age from 9 to 351 days. All patients underwent osteotomy and immobilization with modified Buck's traction and external fixation for a median duration of 41 days. A suprapubic tube was placed in all patients for a median duration of 46.5 days. All patients underwent PICU admission following closure for a median duration of 8 days. Ventilator support was required in 68 % of patients for a median of 3 days. Epidural analgesia was used in all patients and catheters were maintained for a median duration of 19 days. All patients received a blood transfusion over the course of their admission. Patient-controlled analgesia was used in most patients as an adjunct for a median duration of 38.5 days. Other commonly used analgesic adjuncts included acetaminophen, diazepam, clonidine, and dexmedetomidine. TPN was used in 80 % of patients for a median of 7 days with a return of oral feeding thereafter. Overall, the closure success rate in this cohort of patients was 100 %.

DISCUSSION

The outcome of primary bladder closure can have inauspicious consequences that can affect a child's continence for years. The incidence of failed bladder closure can be minimized with the implementation of a detailed plan for immobilization, analgesia, and nutrition guided by an experienced multi-disciplinary team.

CONCLUSION

We have identified several guiding principles for perioperative success in exstrophy patients at our center including Buck's traction with external fixation, provision of adequate postoperative analgesia and sedation, aggressive nutritional support, renal and bladder drainage, and robust antibacterial support. Our high success rate in managing this complex pathology demonstrates its validity and use as a pathway to success.

Effect of Dexmedetomidine on Incidence of Hypertension Following Repair of Coarctation of the Aorta

OBJECTIVE

Recent literature suggests a potential role for dexmedetomidine in reducing the incidence and severity of hypertension following repair of coarctation of the aorta (CoA). The primary aim of this study was to assess the association between dexmedetomidine use and the incidence of hypertension following repair of CoA in pediatric patients.

METHODS

This was a single-center, retrospective cohort study in patients younger than 19 years who underwent surgical repair of CoA between January 1, 2016, and September 30, 2021. Patients were divided into 2 groups: dexmedetomidine initiation within the first 3 hours after surgery or no dexmedetomidine. The primary outcome was incidence of hypertension within the first 4 to 24 hours after repair. Secondary outcomes included the incidence of hypotension and bradycardia.

RESULTS

A total of 80 patients were included, 25 (31.25%) received dexmedetomidine. Median age at the time of procedure was 26 days (IQR, 13-241) in the dexmedetomidine group and 14 days (IQR, 8-53) in the no dexmedetomidine group (p = 0.014). The primary outcome of hypertension was met in 7 patients (28%) in the dexmedetomidine group and 12 patients (21.8%) in the no dexmedetomidine group, p = 0.547. The only variable found to be associated with the incidence of hypertension was age greater than 30 days at the time of procedure. More patients who received dexmedetomidine experienced bradycardia. There was no difference in the incidence of hypotension.

CONCLUSIONS

There was no association between the use of dexmedetomidine and the incidence of -hypertension following repair of CoA in pediatric patients.

Effects of dexmedetomidine on pulmonary function in patients receiving one-lung ventilation: a meta-analysis of randomized controlled trial

BACKGROUND

Mechanical ventilation, particularly one-lung ventilation (OLV), can cause pulmonary dysfunction. This meta-analysis assessed the effects of dexmedetomidine on the pulmonary function of patients receiving OLV.

METHODS

The Embase, PubMed, MEDLINE, Cochrane Library, ClinicalTrials.gov, and Chinese Clinical Trial Registry databases were systematically searched. The primary outcome was oxygenation index (OI). Other outcomes including the incidence of postoperative complications were assessed.

RESULTS

Fourteen randomized controlled trials involving 845 patients were included in this meta-analysis. Dexmedetomidine improved the OI at 30 (mean difference [MD]: 40.49, 95% CI [10.21, 70.78]), 60 (MD: 60.86, 95% CI [35.81, 85.92]), and 90 min (MD: 55, 95% CI [34.89, 75.11]) after OLV and after surgery (MD: 28.98, 95% CI [17.94, 40.0]) and improved lung compliance 90 min after OLV (MD: 3.62, 95% CI [1.7, 5.53]). Additionally, dexmedetomidine reduced the incidence of postoperative pulmonary complications (odds ratio: 0.44, 95% CI [0.24, 0.82]) and length of hospital stay (MD: -0.99, 95% CI [-1.25, -0.73]); decreased tumor necrosis factor-α, interleukin (IL)-6, IL-8, and malondialdehyde levels; and increased superoxide dismutase levels. However, only the results for the OI and IL-6 levels were confirmed by the sensitivity and trial sequential analyses.

CONCLUSIONS

Dexmedetomidine improves oxygenation in patients receiving OLV and may additionally decrease the incidence of postoperative pulmonary complications and shorten the length of hospital stay, which may be related to associated improvements in lung compliance, anti-inflammatory effects, and regulation of oxidative stress reactions. However, robust evidence is required to confirm these conclusions.

Advances in Anesthesia for Shoulder Surgery: A Comprehensive Review of Dexmedetomidine-Enhanced Interscalene Brachial Plexus Block

Surgical procedures on the shoulder pose distinctive challenges in managing pain during the perioperative period, underscoring the importance of exploring innovative anesthesia techniques. This comprehensive review article delves into integrating dexmedetomidine, an alpha-2 adrenergic agonist, within interscalene brachial plexus blocks for shoulder surgery. The review initiates by underscoring the pivotal role of effective anesthesia in shoulder surgery and elucidates the rationale behind investigating dexmedetomidine as an adjunct. It meticulously examines the anatomy and physiology of the brachial plexus, emphasizing its critical significance in shoulder surgery. Furthermore, the article expounds on dexmedetomidine's mechanisms of action and pharmacokinetics, encompassing its safety profile and potential side effects. The conventional interscalene brachial plexus block techniques, along with their limitations and challenges, are discussed, laying the foundation for the integration of dexmedetomidine. The review subsequently delves into exploring the role of dexmedetomidine in regional anesthesia, covering previous studies, mechanisms of action, and the potential advantages of incorporating it into nerve blocks. The review's core concentrates on the practical application of dexmedetomidine-enhanced interscalene brachial plexus blocks. This includes discussions on administration techniques, dosage guidelines, and compelling evidence supporting its utilization. Clinical scenarios where this approach proves most advantageous are thoroughly explored, comparing its effectiveness with traditional techniques in terms of pain control and patient outcomes. A comprehensive examination of relevant clinical trials and case studies highlights the evidence supporting its efficacy. The review also underscores safety considerations associated with dexmedetomidine. It proposes strategies for mitigating risks to ensure patient safety. Insights into future directions and research are provided, encompassing ongoing studies, areas necessitating further investigation, and potential refinements in technique. Finally, the article summarizes key findings, emphasizing the practicality of dexmedetomidine-enhanced interscalene brachial plexus blocks in shoulder surgery and its far-reaching implications for clinical practice and patient care.

Dexmedetomidine as an anesthetic adjunct is associated with reduced complications and cardiac intensive care unit length of stay after heart valve surgery

BACKGROUND

We sought to explore the relationship between dexmedetomidine as an anesthetic adjuvant in cardiac surgery and postoperative complications and length of stay (LOS) in the cardiac intensive care unit (CICU).

METHODS

We conducted a retrospective study of patients aged 18 years and older who underwent heart valve surgery between October 2020 and June 2022. The primary endpoint of the study was major postoperative complications (cardiac arrest, atrial fibrillation, myocardial injury/infarction, heart failure) and the secondary endpoint was prolonged CICU LOS (defined as LOS > 90th percentile). Multivariate logistic regression analysis was performed for variables that were significant in the univariate analysis.

RESULTS

A total of 856 patients entered our study. The 283 patients who experienced the primary and secondary endpoints were included in the adverse outcomes group, and the remaining 573 were included in the prognostic control group. Multivariate logistic regression analysis revealed that age > 60 years (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.23-2.31; p < 0.01), cardiopulmonary bypass (CPB) > 180 min (OR, 1.62; 95% CI, 1.03-2.55; p = 0.04) and postoperative mechanical ventilation time > 10 h (OR, 1.84; 95% CI, 1.35-2.52; p < 0.01) were independent risk factors for major postoperative complications; Age > 60 years (OR, 3.20; 95% CI, 1.65-6.20; p < 0.01), preoperative NYHA class 4 (OR, 4.03; 95% CI, 1.74-9.33; p < 0.01), diabetes mellitus (OR, 2.57; 95% CI, 1.22-5.41; p = 0.01), Intraoperative red blood cell (RBC) transfusion > 650 ml (OR, 2.04; 95% CI, 1.13-3.66; p = 0.02), Intraoperative bleeding > 1200 ml (OR, 2.69; 95% CI, 1.42-5.12; p < 0.01) were independent risk factors for prolonged CICU length of stay. Intraoperative use of dexmedetomidine as an anesthetic adjunct was a protective factor for major complications (odds ratio, 0.51; 95% confidence interval, 0.35-0.74; p < 0.01) and prolonged CICU stay. (odds ratio, 0.37; 95% confidence interval, 0.19-0.73; p < 0.01).

CONCLUSIONS

In patients undergoing heart valve surgery, age, duration of cardiopulmonary bypass, and duration of mechanical ventilation are associated with major postoperative complication. Age, preoperative NYHA classification 4, diabetes mellitus, intraoperative bleeding, and RBC transfusion are associated with increased CICU length of stay. Intraoperative use of dexmedetomidine may improve such clinical outcomes.

Alpha2 Adrenergic Modulation of Spike-Wave Epilepsy: Experimental Study of Pro-Epileptic and Sedative Effects of Dexmedetomidine

In the present report, we evaluated adrenergic mechanisms of generalized spike-wave epileptic discharges (SWDs), which are the encephalographic hallmarks of idiopathic generalized epilepsies. SWDs link to a hyper-synchronization in the thalamocortical neuronal activity. We unclosed some alpha2-adrenergic mechanisms of sedation and provocation of SWDs in rats with spontaneous spike-wave epilepsy (WAG/Rij and Wistar) and in control non-epileptic rats (NEW) of both sexes. Dexmedetomidine (Dex) was a highly selective alpha-2 agonist (0.003-0.049 mg/kg, i.p.). Injections of Dex did not elicit de novo SWDs in non-epileptic rats. Dex can be used to disclose the latent form of spike-wave epilepsy. Subjects with long-lasting SWDs at baseline were at high risk of absence status after activation of alpha2- adrenergic receptors. We create the concept of alpha1- and alpha2-ARs regulation of SWDs via modulation of thalamocortical network activity. Dex induced the specific abnormal state favorable for SWDs-"alpha2 wakefulness". Dex is regularly used in clinical practice. EEG examination in patients using low doses of Dex might help to diagnose the latent forms of absence epilepsy (or pathology of cortico-thalamo-cortical circuitry).

A pilot study of ADRA2A genotype association with doses of dexmedetomidine for sedation in pediatric patients

STUDY OBJECTIVE

Dexmedetomidine is titrated to achieve sedation in the pediatric and cardiovascular intensive care units (PICU and CVICU). In adults, dexmedetomidine response has been associated with an ADRA2A polymorphism (rs1800544); CC genotype is associated with an increased sedative response compared with GC and GG. To date, this has not been studied in children.

DESIGN

We conducted a pilot study to determine whether ADRA2A genotype is associated with dexmedetomidine dose in children.

MEASUREMENTS AND MAIN RESULTS

Forty intubated PICU or CVICU patients who received dexmedetomidine as a continuous infusion for at least 2 days were genotyped for ADRA2A with a custom-designed TaqMan® Assay. Ten (25%) subjects were wildtype (GG), 15 (37.5%) were heterozygous (GC), and 15 (37.5%) were homozygous (CC) variant. The maximum dexmedetomidine doses (mCg/kg/h) were not different between genotype groups CC (1, 0.3-1.2), GC (1, 0.3-1.3), and GG (0.8, 0.3-1.2), (p = 0.37); neither were mean dexmedetomidine doses for these respective genotype groups 0.68 (0.24-1.07), 0.72 (0.22-0.98), 0.58 (0.3-0.94), (p = 0.67).

CONCLUSIONS

These findings did not confirm the results from adult studies where ADRA2A polymorphisms correlate with dexmedetomidine response, therefore highlighting the need for pediatric studies to validate PGx findings in adults prior to implementation in pediatrics.