Use of Dexmedetomidine in Cardiothoracic and Vascular Anesthesia

Does dexmedetomidine reduce the risk of acute kidney injury after cardiac surgery? A meta-analysis of randomized controlled trials

BACKGROUND

Acute Kidney Injury (AKI) is a common complication after cardiac surgery and has been associated with poor outcomes. Dexmedetomidine (DEX) has been shown to confer direct renoprotection based on some animal and clinical studies, but data from other trials came to the opposite conclusion following cardiac surgery. This meta-analysis was conducted to evaluate the effects of perioperative DEX administration on the occurrence of AKI and the outcomes after cardiac surgery.

METHODS

We searched databases including EMBASE, PubMed, and Cochrane CENTRAL for Randomized Controlled Trials (RCTs) focused on DEX for AKI in adult patients after cardiac surgery. The primary outcome was incidence of AKI. Secondary outcomes were Mechanical Ventilation (MV) duration, Intensive Care Unit (ICU) Length Of Stay (LOS), hospital LOS and mortality.

RESULTS

Fifteen trials enrolling 2907 study patients were collected in the meta-analyses. Compared with controls, DEX reduced the incidence of postoperative AKI (Odds Ratio [OR = 0.66]; 95% Confidence Interval [95% CI 0.48-0.91]; p = 0.01), and there was no significant difference between groups in postoperative mortality (OR = 0.63; 95% CI 0.32-1.26; p = 0.19), MV duration (Weighted Mean Difference [WMD = -0.44]; 95% CI -1.50-0.63; p = 0.42), ICU LOS (WMD = -1.19; 95% CI -2.89-0.51; p = 0.17), and hospital LOS (WMD = -0.31; 95% CI -0.76-0.15; p = 0.19).

CONCLUSIONS

Perioperative DEX reduced the incidence of postoperative AKI in adult patients undergoing cardiac surgery. No significant decrease existed in mortality, MV duration, ICU LOS and hospital LOS owing to DEX administration.

Impact of intravenous dexmedetomidine on postoperative gastrointestinal function recovery: an updated meta-analysis

BACKGROUND

Postoperative ileus (POI) is a complication that may occur after abdominal or nonabdominal surgery. Intravenous dexmedetomidine (Dex) has been reported to accelerate postoperative gastrointestinal function recovery; however, updated evidence is required to confirm its robustness.

METHODS

To identify randomized controlled trials examining the effects of perioperative intravenous Dex on gastrointestinal function recovery in patients undergoing noncardiac surgery, databases including MEDLINE, EMBASE, Google Scholar, and Cochrane Library were searched on August 2023. The primary outcome was time to first flatus. Secondary outcomes included time to oral intake and defecation as well as postoperative pain scores, postoperative nausea/vomiting (PONV), risk of hemodynamic instability, and length of hospital stay (LOS). To confirm its robustness, subgroup analyses and trial sequential analysis were performed.

RESULTS

The meta-analysis of 22 randomized controlled trials with 2566 patients showed that Dex significantly reduced the time to flatus [mean difference (MD):-7.19 h, P <0.00001), time to oral intake (MD: -6.44 h, P =0.001), time to defecation (MD:-13.84 h, P =0.008), LOS (MD:-1.08 days, P <0.0001), and PONV risk (risk ratio: 0.61, P <0.00001) without differences in hemodynamic stability and pain severity compared with the control group. Trial sequential analysis supported sufficient evidence favoring Dex for accelerating bowel function. Subgroup analyses confirmed the positive impact of Dex on the time to flatus across different surgical categories and sexes. However, this benefit has not been observed in studies conducted in regions outside China.

CONCLUSIONS

Perioperative intravenous Dex may enhance postoperative gastrointestinal function recovery and reduce LOS, thereby validating its use in patients for whom postoperative ileus is a significant concern.

Comparison of dexmedetomidine and opioids as local anesthetic adjuvants in patient controlled epidural analgesia: a meta-analysis

BACKGROUND

Data on the efficacy and incidence of adverse effects associated with dexmedetomidine (DEX) as a local anesthetic adjuvant for patient-controlled epidural analgesia (PCEA) are inconclusive. This meta-analysis assessed the efficacy and risks of DEX for PCEA using opioids as a reference.

METHODS

Two researchers independently searched PubMed, Embase, Cochrane Library, and China Biology Medicine for randomized controlled trials comparing DEX and opioids as local anesthetic adjuvants in PCEA.

RESULTS

In total, 636 patients from seven studies were included in this meta-analysis. Postoperative patients who received DEX had lower visual analog scale (VAS) scores than those who received opioids at 4-8 h (mean difference [MD]: 0.61, 95% CI [0.45, 0.76], P < 0.001, I2 = 0%), 12 h (MD: 0.85, 95% CI [0.61, 1.09], P < 0.001, I2 = 0%), 24 h (MD: 0.59, 95% CI [0.06, 1.12], P = 0.030, I2 = 82%), and 48 h (MD: 0.54, 95% CI [0.05, 1.02], P = 0.030, I2 = 91%). Additionally, patients who received DEX had a lower incidence of itching (odds ratio [OR]: 2.86, 95% CI [1.18, 6.95], P = 0.020, I2 = 0%) and nausea and vomiting (OR: 6.83, 95% CI [3.63, 12.84], P < 0.001, I2 = 24%). In labor analgesia, no significant differences in neonatal (pH and PaO2 of cord blood, fetal heart rate) or maternal outcomes (duration of labor stage, mode of delivery) were found between the DEX and opioid groups.

CONCLUSIONS

Compared with opioids, using DEX as a local anesthetic adjuvant in PCEA improved postoperative analgesia and reduced the incidence of itching and nausea and vomiting without increasing the incidence of adverse events.

Sedation with propofol/remifentanil versus dexmedetomidine / remifentanil for patients undergoing transcatheter aortic valve implant: A retrospective study between 2012 and 2019

BACKGROUND AND OBJECTIVES

Percutaneous implantation of an aortic valve prosthesis is a therapeutic alternative for patients with severe aortic stenosis. The procedure is traditionally performed under general anaesthesia; however, sedation is now gaining in popularity because it reduces the need for vasoactive drugs and shortens the patient's stay in the critical care unit and on the ward. The aim of this study is to evaluate the clinical efficacy, safety and potential benefits of sedation with dexmedetomidine in patients undergoing percutaneous implantation of an aortic valve prosthesis in terms of haemodynamic and respiratory complications.

MATERIALS AND METHODS

We performed a retrospective study of 222 patients that had undergone percutaneous implantation of an aortic valve prosthesis between 2012 and 2019 under sedation with either dexmedetomidine plus remifentanil (DEX-RMF) or propofol plus remifentanil (PROPO-RMF). We collected data on complications, mainly haemodynamic and respiratory, during and after the procedure.

RESULTS

No significant differences were found between sedation with dexmedetomidine and propofol (in combination with remifentanil) in terms of haemodynamic stability and intraprocedural cerebral blood oxygen. In the DEX-RMF group, however, mean blood pressure, midazolam dose, and duration of anaesthesia were lower compared with the PROPO-RMF group, but the incidence of haemodynamic and respiratory complications did not differ significantly between groups.

CONCLUSIONS

Our results show that sedation, particularly with adjuvant dexmedetomidine, is a valid anaesthetic techniques in percutaneous aortic valve prosthesis implantation.

Multiple uses of dexmedetomidine in small animals: a mini review

Dexmedetomidine is an alpha-2 adrenergic agonist, which use had an exponential increase in human and veterinary medicine in the last 10 years. The aim of this mini review is to summarize the various uses of dexmedetomidine underlining its new applications and capabilities in the small animals' clinical activity. While this drug was born as sedative in veterinary medicine, some studies demonstrated to be effective as an analgesic both in single administration and in continuous infusion. Recent studies have also shown the role of dexmedetomidine as an adjuvant during locoregional anesthesia, increasing the duration of the sensitive block and consequently decreasing the demand for systemic analgesics. The various analgesic properties make dexmedetomidine an interesting drug for opioid-free analgesia. Some studies highlighted a potential neuroprotective, cardioprotective and vasculoprotective role of dexmedetomidine, thus conferring it a place in critical care medicine, such as trauma and septic patients. Dexmedetomidine has demonstrated to be a multitasking molecule and it is ready to face new challenges.

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

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

Clinical application of dexmedetomidine combined with dezocine in local anesthesia for endoscopic dacryocystorhinostomy

OBJECTIVE

To investigate the clinical effect of dexmedetomidine combined with dezocine in local anesthesia for endoscopic dacryocystorhinostomy (DCR).

METHODS

Ninety patients undergoing elective endoscopic DCR were randomly divided into two groups, local anesthesia group (LA group n = 45) and general anesthesia group (GA group, n = 45). These subjects were all American Society of Anesthesiologists (ASA)-Physical Status I-II patients. The changes of mean arterial pressure (MAP) and heart rate (HR) were observed and recorded before anesthesia (T0), after anesthesia (T1), at the beginning of surgery (T2), and at the end of surgery (T3). The visual analogue scale (VAS) score was observed and recorded immediately after awakening from anesthesia and at 1, 2, 6, and 12 h after surgery. Additionally, the occurrence of adverse reactions after surgery and the sedation-agitation scale (SAS) score after awakening were recorded.

RESULTS

Compared with the LA group, the MAP and HR of the GA group were significantly lower at T1 and T2, but significantly higher at T3. Local anesthesia was associated with lower VAS score immediately after awakening and at 1, 2, 6, and 12 h after surgery. Also, local anesthesia caused a lower incidence of postoperative agitation, nausea, and vomiting. The SAS score in the LA group was markedly higher than that in the GA group.

CONCLUSION

Local anesthesia with dexmedetomidine and dezocine as adjuvants in endoscopic DCR has more stable hemodynamics and reduces the stress response during perioperative period. Also, this anesthesia achieves better postoperative sedation and analgesia effects, reduces postoperative complications, and improves the quality of awakening from anesthesia. Collectively, local anesthesia is a comfortable and safe option for patients with high risks of general anesthesia and those unwilling to receive general anesthesia.

Does dexmedetomidine combined with levobupivacaine in inferior alveolar nerve blocks among patients undergoing impacted third molar surgery control postoperative morbidity?

Background

Postoperative analgesia (POA) is an important determinant of successful treatment. Dexmedetomidine (DEX) has recently gained attention as a promising adjuvant to local anesthetics (LA). The present study aimed to evaluate the efficacy and safety of levobupivacaine (LB) as an adjuvant during inferior alveolar nerve block (IANB) in the extraction of lower impacted third molars (LITM).

Methods

A prospective, randomized, placebo-controlled, triple-blind, parallel-arm, and clinical study was performed on 50 systemically healthy participants who required removal of an asymptomatic LITM. Using a 1:1 distribution, the participants were randomized into two groups (n = 25). Group L (control group) received 1.8 mL of 0.5% LB and 0.2 mL normal saline (placebo) and Group D (study group) received a blend of 1.8 mL of 0.5% LB and 0.2 mL (20 µg) DEX. The primary outcome variable was the duration of POA and hemodynamic stability, and the secondary variable was the total number of analgesics required postoperatively for up to 72 h. The participants were requested to record the time of rescue analgesic use and the total number of rescue analgesics taken. The area under the curve was plotted for the total number of analgesics administered. The pain was evaluated using the visual analog scale. Data analysis was performed using paired students and unpaired t-test, Mann–Whitney U test, Chi-square test, and receiver operating characteristic analysis. Statistical significance was set at P < 0.05.

Results

The latency, profoundness of anesthesia, and duration of POA were statistically significant (P < 0.05). The differences between mean pain scores at 6, 12, 24, 48, and 72 h were found to be significant (each P = 0.0001). Fewer analgesics were required by participants in group D (2.12 ± 0.33) than in L (4.04 ± 0.67), with a significant difference (P = 0.0001).

Conclusion

Perineurally administered LA with DEX is a safe, effective, and therapeutic approach for improving latency, providing profound POA, and reducing the need for postoperative analgesia.

Influence of Dexmedetomidine on Diaphragm Function and Postoperative Outcomes in ICU Patients with Mechanical Ventilation

Objective

To probe into the influence of dexmedetomidine (DEX) on diaphragm function and postoperative outcomes of mechanically ventilated patients in the intensive care unit (ICU).

Methods

84 patients with mechanical ventilation (MV) in the ICU of our hospital were selected as the research participants, including 38 patients in the control group (CG) sedated with midazolam (MZ) and 46 patients in the research group (RG) with DEX sedation. Ramsay sedation score, visual analogue scale (VAS), and restlessness score (RS) were used to evaluate their state before sedation (T0), as well as 2 h (T1), 6 h (T2), and 24 h (T3) after sedation, and the alterations of mean arterial pressure (MAP) and heart rate (HR) were recorded. Serum cortisol (Cor), adrenocorticotropic hormone (ACTH), superoxide dismutase (SOD), malondialdehyde (MDA), interleukin- (IL-) 1β, IL-6, and tumor necrosis factor-α (TNF-α) were measured before and 24 h after sedation. The end-inspiratory diaphragm thickness (DTei) and end-expiratory diaphragm thickness (DTee) were measured within 2 h after the initiation of MV and 5 min after the spontaneous breathing test (SBT), and the diaphragm thickening fraction (DTF) was calculated. Finally, the ventilator weaning, MV time, and the incidence of adverse reactions (ADs) of the two groups were counted.

Results

T0 and T3 witnessed no distinct difference in Ramsay, VAS, and RS scores between the two arms (P > 0.05), but at T1 and T2, RG had better sedation state and lower VAS and RS scores than CG (P < 0.05), with more stable vital signs (P < 0.05). After sedation, the contents of oxidative stress and inflammatory factors in RG were lower, while DTee, DTei, and DTF were higher, versus CG (P < 0.05). Moreover, RG presented higher success rate of first ventilator weaning, less MV time, and lower incidence of ADs than CG (P < 0.05).

Conclusions

DEX is effective in mechanically ventilated patients in the ICU, which can protect patients against diaphragm function damage, improve the success rate of ventilator weaning, and benefit the postoperative outcome, with excellent and rapid sedation effect and less stress damage to patients.

Protective role of dexmedetomidine against sevoflurane-induced postoperative cognitive dysfunction via the microRNA-129/TLR4 axis

The involvement of Dexmedetomidine (Dex) has been indicated in postoperative cognitive dysfunction (POCD), while the mechanism is not well characterized. This study estimated the mechanism of Dex in POCD. Rats were anesthetized with sevoflurane (SEV) to evoke POCD and then subjected to Morris water maze test to detect the cognitive and behavioral function. Then, the damage of hippocampus and cortex, and apoptosis and activity of neurons were examined. Microarray analysis was performed to screen out the differentially expressed microRNAs (miRs) in rats after Dex treatment. The cognitive and behavioral functions and neuronal activity of rats were detected after miR-129 antagomir injection. The target of miR-129 was predicted. The levels of TLR4 and NF-κB p65 in hippocampus and cortex were measured. Dex treatment alleviated SEV-induced behavior and cognitive impairments in rats, promoted neuronal activity and hindered neuronal apoptosis. After treatment with Dex, miR-129 expression was elevated in brain tissues, and the neuroprotection of Dex on POCD rats was partially annulled after injection of miR-129 antagomir. Furthermore, miR-129 targeted TLR4 and prevented the phosphorylation of NF-κB p65. In summary, Dex ameliorated SEV-induced POCD by elevating miR-129 and inhibiting TLR4 and NF-κB p65 phosphorylation. This study may shed new lights on POCD treatment.

Dexmedetomidine versus fentanyl as adjuvants to ropivacaine for epidural anaesthesia: A systematic review and meta-analysis

BACKGROUND

Several randomized controlled trials (RCTs) have evaluated the use of dexmedetomidine versus fentanyl as adjuvants to ropivacaine for epidural anaesthesia, yet the results are conflicting. We aimed to conduct this meta-analysis to assess the effects and safety of dexmedetomidine and fentanyl as adjuvants to ropivacaine for epidural anaesthesia.

METHODS

Cochrane Library et al databases were searched from inception to Jan 28, 2020. The synthesised effect sizes were presented as mean difference (MD) or odd of risk (OR) and 95% confidence intervals (95% CI).

RESULTS

Nine RCTs with a total of 672 patients were included. The synthesised results indicated that the mean time to the onset of sensory block (MD: -2.82, 95% CI (-4.84, -0.80)), and the time to maximum motor block (MD: -4.35, 95% CI (-7.31, -1.40)) in dexmedetomidine group was significantly less than that of fentanyl group, while the mean time to rescue analgesia in dexmedetomidine group was significantly increased (MD: 99.13, 95% CI (82.89, 115.37)). The incidence of nausea and vomiting (OR: 0.43, 95% CI (0.29, 0.66)), and shivering (OR: 0.34, 95% CI (0.18, 0.63)) in dexmedetomidine group was significantly reduced, yet the incidence of oral dryness in dexmedetomidine group was significantly increased OR: 5.31, 95% CI (1.69, 16.69)).

CONCLUSIONS

Dexmedetomidine is better than fentanyl as adjuvant to ropivacaine for epidural anaesthesia with better effects and less adverse events.

Effect of dexmedetomidine on hemodynamic changes and inflammatory responses in patients undergoing off-pump coronary-artery bypass grafting

The aim of the present study was to determine the effect of dexmedetomidine on hemodynamic changes and inflammatory responses in patients undergoing off-pump coronary artery bypass grafting (OPCABG). A total of 300 patients about to receive OPCABG were randomized evenly into the control group (n=116) and study group (n=123). Intravenous dexmedetomidine pump infusion was administered to patients in the study group at a rate of 0.4 µg.kg^-1.h^-1. The control group received physiological saline at the same infusion speed. Changes in hemodynamic parameters and inflammatory indices were compared between the two groups. Hemodynamic parameters, such as the heart rate and mean arterial pressure, were lower in patients from the study group, compared with that in the control group (both P<0.05). The levels of pro-inflammatory factors, such as interleukin (IL)-6, tumor necrosis factor-α and C-reactive protein, were also reduced in the study group (P<0.05). The observed levels of IL-10 were lower in the control group compared with that in the study group, although a statistically significant difference was not achieved. Thus, the administration of dexmedetomidine in patients undergoing OPCABG stabilized hemodynamics and reduced inflammation. The present study was registered at the Chinese Clinical Trial Registry, under the trial registration number ChiCTR-OOC-15005978 (2015).

Procedural sedation and analgesia for percutaneous high-tech cardiac procedures

The interest in percutaneous high-tech cardiac procedures has increased in recent years together with its safety and efficacy. In fragile patients, procedural sedation and analgesia are used to perform most of the procedures. General anesthesia remains the technique of choice during the team learning curve and might be required in selected patients or in emergent situations. Despite the high costs of percutaneous high-tech cardiac procedures, the decrease in length of hospital stays, rate of intensive care admission and complications, balance the increase in devices costs. In fragile patients who undergo percutaneous high tech cardiac procedures, the primary role of the anesthesiologist is to prevent the need for postprocedural intensive care unit and complications rate. Starting from the experience of a large university third level hospital we identified the eight most commonly performed contemporary percutaneous high tech cardiac procedures (ventricular tachycardia and atrial fibrillation ablation, protected percutaneous coronary intervention, transcatheter aortic valve implantation, MitraClip® (Abbott Laboratories; Abbott Park, IL, USA), percutaneous patent foramen ovale closure, left atrial appendage closure, and dysfunctional lead extraction), discuss the role of procedural sedation and analgesia in this setting, and explore future perspectives.

Use of Dexmedetomidine in a Parturient With Multiple Endocrine Neoplasia Type 2A Undergoing Adrenalectomy and Thyroidectomy: A Case Report

Dexmedetomidine is a selective α2-agonist, frequently used in perioperative medicine as anesthesia adjunct. The medication carries a Food and Drug Administration pregnancy category C designation and is therefore rarely used for parturients undergoing nonobstetric surgery. We are reporting the use of dexmedetomidine in the anesthetic management of a parturient undergoing minimally invasive unilateral adrenalectomy for pheochromocytoma during the second trimester of pregnancy. Additionally, because of the multiple endocrine neoplasia type 2A constellation with diagnosis of medullary thyroid cancer, the patient underwent a total thyroidectomy 1 week after the adrenalectomy.