Perioperative dexmedetomidine improves mortality in patients undergoing coronary artery bypass surgery

Intraoperative Dexmedetomidine Use for Enhanced Recovery after Surgery (ERAS) in Cardiac Surgery-Single Center Retrospective Observational Cohort Study

Background and Objectives: Dexmedetomidine, an alpha-2 agonist, is used as an adjunct to anesthesia in enhanced recovery after surgery (ERAS) programs. One of its advantages is the opioid-sparing effect which can facilitate early extubation and recovery. When the ERAS cardiac society was set in 2017, our facility was already using the ERAS program, in which the "fast-track Anesthesia" was facilitated by the intraoperative infusion of dexmedetomidine. Our objective is to share our experience and investigate the potential impact of intraoperative dexmedetomidine use as a part of the ERAS program on patient outcomes in elective cardiac surgery. Materials and Methods: An observational retrospective cohort study was conducted at a university hospital in Switzerland. The patients who underwent elective cardiac surgery with cardiopulmonary bypass between 1 June 2017 and 31 August 2018 were included in this analysis (n = 327). Regardless of the surgery type, all the patients received a standardized fast-track anesthesia protocol inclusive of dexmedetomidine infusion, reduced opioid dose, and parasternal nerve block. The primary outcome was the postoperative time when the criteria for extubation were met. Three groups were identified: group 0-(extubated in the operating room), group < 6 (extubated in less than 6 h), and group > 6 (extubated in >6 h). The secondary outcomes were adverse events, length of stay in ICU and in hospital, and total hospitalization costs. Results: Dexmedetomidine was well-tolerated, with no significant adverse events reported. Early extubation was performed in 187 patients (57%). Group 3 had a significantly longer length of stay in the ICU (median: 70 h vs. 25 h) and in hospital (17 vs. 12 days), and consequently higher total hospitalization costs (CHF 62,551 vs. 38,433) compared to the net data from the other two groups (p < 0.0001). Conclusions: Our findings suggest that dexmedetomidine can be safely used as part of the opioid-sparing anesthesia protocol in patients undergoing elective cardiac surgery with cardiopulmonary bypass with the potential to facilitate early extubation, shorter ICU and hospital stays, and reduced hospitalization costs.

Protocol: dexmedetomidine on myocardial injury after noncardiac surgery-a multicenter, double-blind, controlled trial

AIMS

Myocardial injury after noncardiac surgery (MINS) is common in elderly patients and considered as an independent predictor of 30-day mortality after noncardiac surgery. Dexmedetomidine possesses cardiac-protective profile. Previous clinical studies have found that perioperative application of dexmedetomidine is associated with decreased 1-year mortality in patients undergoing cardiac surgery. The current study protocol aims to investigate the effects of dexmedetomidine on the incidence of MINS, complications, and 30-day mortality in elderly patients subjected to noncardiac surgery.

METHODS

A multicenter, randomized, controlled, double-blind, prospective trial is designed to explore cardiac protection of dexmedetomidine in the elderly patients undergoing noncardiac surgery. A total of 960 patients aged over 65 years will be recruited and randomly assigned to dexmedetomidine group (group Dex) and normal saline placebo group (group NS) in a ratio of 1:1. Patients in group Dex will receive a bolus dose of 0.5 μg/kg dexmedetomidine within 10 min before surgical incision, followed by a consistent infusion at the rate of 0.3-0.5 μg/kg/h throughout the operation. Group NS patients will receive the same volume of normal saline. The primary outcome is the incidence of MINS via detecting the hs-TnT level within 3 days after the operation. The secondary outcome includes myocardial ischemic symptoms, the incidence of major adverse cardiovascular events (MACE) in hospital, length of ICU and postoperative hospital stay, the incidence of inhospital complications, and 30-day all-cause mortality.

DISCUSSION

The results of the current study will illustrate the effect of dexmedetomidine on myocardial injury for elderly patients undergoing major noncardiac surgery.

TRIAL REGISTRATION

The trial was registered with Chinese Clinical Trial Registry (CHICTR) on Aug 24, 2021 (ChiCTR2100049946, http://www.chictr.org.cn/showproj.aspx?proj=131804 ).

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.

Dexmedetomidine attenuates inflammation and organ injury partially by upregulating Nur77 in sepsis

PURPOSE

The aim of this study was to investigate the effect of dexmedetomidine (Dex) on inflammation and organ injury in sepsis, as well as the potential relationship between Dex and nuclear receptor 77 (Nur77).

METHODS

We investigated the effects of dexmedetomidine on lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells and organ injury in the cecal ligation and puncture (CLP) mouse model. Additionally, we examined the relationship between dexmedetomidine and Nur77. The expression levels of Nur77 in RAW264.7 cells were analyzed under various types of stimulation using quantitative reverse transcription polymerase chain reaction and western blot analysis. Inflammatory cytokine levels in the cells were evaluated using enzyme-linked immunoassay. Organ injuries were assessed by examining tissue histology and pathology of the lung, liver, and kidney.

RESULTS

Dexmedetomidine increased the expression of Nur77 and IL-10, and downregulated inflammatory cytokines (IL-1β and TNF-α) in LPS-treated RAW264.7 cells. The effect of dexmedetomidine on inhibiting inflammation in LPS-treated RAW264.7 cells was promoted by overexpressing Nur77, while it was reversed by downregulating Nur77. Additionally, dexmedetomidine promoted the expression of Nur77 in the lung and CLP-induced pathological changes in the lung, liver, and kidney. Activation of Nur77 with the agonist Cytosporone B (CsnB) significantly suppressed the production of IL-1β and TNF-α in LPS-treated RAW264.7 cells. In contrast, knockdown of Nur77 augmented IL-1β and TNF-α production in LPS-treated RAW264.7 cells.

CONCLUSION

Dexmedetomidine can attenuate inflammation and organ injury, at least partially, via upregulating Nur77 in sepsis.

Narrative review of systemic inflammatory response mechanisms in cardiac surgery and immunomodulatory role of anesthetic agents

Although surgical techniques and perioperative care have made significant advances, perioperative mortality in cardiac surgery remains relatively high. Single- or multiple-organ failure remains the leading cause of postoperative mortality. Systemic inflammatory response syndrome (SIRS) is a common trigger for organ injury or dysfunction in surgical patients. Cardiac surgery involves major surgical dissection, the use of cardiopulmonary bypass (CPB), and frequent blood transfusions. Ischemia-reperfusion injury and contact activation from CPB are among the major triggers for SIRS. Blood transfusion can also induce proinflammatory responses. Here, we review the immunological mechanisms of organ injury and the role of anesthetic regimens in cardiac surgery.

Association between intraoperative dexmedetomidine and all-cause mortality and recurrence after laparoscopic resection of colorectal cancer: Follow-up analysis of a previous randomized controlled trial

Background

Dexmedetomidine (DEX) has been widely applied in the anesthesia and sedation of patients with oncological diseases. However, the potential effect of DEX on tumor metastasis remains contradictory. This study follows up on patients who received intraoperative DEX during laparoscopic resection of colorectal cancer as part of a previous clinical trial, examining their outcomes 5 years later.

Methods

Between June 2015 and December 2015, 60 patients undergoing laparoscopic colorectal resection were randomly assigned to the DEX and control groups. The DEX group received an initial loading dose of 1μ/kg before surgery, followed by a continuous infusion of 0.3μg/kg/h during the operation and the Control group received an equivalent volume of saline. A 5-year follow-up analysis was conducted to evaluate the overall survival, disease-free survival, and tumor recurrence.

Results

The follow-up analysis included 55 of the 60 patients. The DEX group included 28 patients, while the control group included 27 patients. Baseline characteristics were comparable between the two groups, except for vascular and/or neural invasion of the tumor in the DEX group (9/28 vs. 0/27, p = 0.002). We did not observe a statistically significant benefit but rather a trend toward an increase in overall survival and disease-free survival in the DEX group, 1-year overall survival (96.4% vs. 88.9%, p = 0.282), 2-year overall survival (89.3% vs. 74.1%, p = 0.144), 3-year overall survival (89.3% vs. 70.4%, p = 0.08), and 5-year overall survival (78.6% vs. 59.3%, p = 0.121). The total rates of mortality and recurrence between the two groups were comparable (8/28 vs. 11/27, p = 0.343).

Conclusion

Administration of DEX during laparoscopic resection of colorectal cancer had a nonsignificant trend toward improved overall survival and disease-free survival.

Clinical Trial Registration

http://www.chictr.org.cn/, identifier ChiCTRIOR-15006518.

Comparative Efficacy of Adjuvant Nonopioid Analgesia in Adult Cardiac Surgical Patients: A Network Meta-Analysis

OBJECTIVES

To compare the relative efficacy of adjuvant nonopioid analgesic regimens in adult cardiac surgical patients.

DESIGN

This frequentist, random-effects network meta-analysis (NMA) was prospectively registered on PROSPERO (CRD42021282913) and conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses for Network Meta-Analyses (PRISMA-NMA). The risk of bias (RoB) and confidence of evidence were assessed by RoB 2 and Confidence in Network Meta-Analysis, respectively. Relevant databases were searched from inception to October 9, 2021.

SETTING

A total of 124 (N = 26,257) randomized controlled trials were included, of which 110 were analyzed.

PARTICIPANTS

Trials enrolling adults (≥18 years of age) undergoing cardiac surgery that compared nonopioid analgesics against other nonopioid analgesics, placebo, or no additional treatment, as adjuvants to standard analgesic management, and reported at least 1 of the outcomes of interest.

MEASUREMENT AND MAIN RESULTS

Outcomes of interest included resting postoperative pain scores at 24 hours. Compared with standard care and/or placebo, pain scores were reduced significantly by 10 different regimens, including acetaminophen (N = 176; mean difference [MD] -0.66 points, 95% CI -1.16 to -0.15 points; high confidence), magnesium (N = 323; -0.05 points, 95% CI -0.07 to -0.02 points; high confidence), gabapentin (N = 96; MD -0.40 points, 95% CI -0.71 to -0.09; moderate confidence), and clonidine (N = 64; MD v0.38 points, 95% CI -0.73 to v0.04 points; moderate confidence). Indomethacin, diclofenac, magnesium, and gabapentin significantly reduced 24-hour opioid consumption. Four regimens significantly decreased the intensive care unit length of stay. Hydrocortisone, dexmedetomidine, and clonidine significantly decreased the duration of mechanical ventilation. Magnesium decreased, while methylprednisolone significantly increased, the risk of myocardial infarction.

CONCLUSIONS

Given the increasing emphasis on enhanced recovery after surgery(ERAS) protocols and the eventual goal of limiting opiate prescriptions postoperatively, the authors' data suggested far greater use of nonopioid adjuncts to minimize pain and enhance recovery following cardiac surgery.

Effect of Dexmedetomidine on Cardiac Surgery Patients

ABSTRACT

Dexmedetomidine, an alpha-2 adrenoreceptor agonist that is widely used as a sedative medication, is becoming more and more attractive in clinical application on cardiac surgery patients. In this review, we aim to summarize and discuss both retrospective studies and clinical trials regarding the effect of dexmedetomidine on patients who underwent cardiac surgery (including coronary artery bypass grafting, valve surgery, aortic surgery, percutaneous coronary intervention, and so on), which illustrates that the clinical effects of dexmedetomidine could effectively reduce mortality, major complications, and the intensive care unit and hospital length of stay without comprising safety. In addition, inconsistent results from both retrospective studies and clinical trials have also been demonstrated. Although the effectiveness and safety of dexmedetomidine on cardiac surgery patients is suggested, high-quality clinical trials are needed for further verification.

Dexmedetomidine Increases MMP-12 and MBP Concentrations after Coronary Artery Bypass Graft Surgery with Extracorporeal Circulation Anaesthesia without Impacting Cognitive Function: A Randomised Control Trial

Postoperative neurological deficits remain a concern for patients undergoing cardiac surgeries. Even minor injuries can lead to neurocognitive decline (i.e., postoperative cognitive dysfunction). Dexmedetomidine may be beneficial given its reported neuroprotective effect. We aimed to investigate the effects of dexmedetomidine on brain injury during cardiac surgery anaesthesia. This prospective observational study analysed data for 46 patients who underwent coronary artery bypass graft surgery with extracorporeal circulation between August 2018 and March 2019. The patients were divided into two groups: control (CON) with typical anaesthesia and dexmedetomidine (DEX) with dexmedetomidine infusion. Concentrations of the biomarkers matrix metalloproteinase-12 (MMP-12) and myelin basic protein (MBP) were measured preoperatively and at 24 and 72 h postoperatively. Cognitive evaluations were performed preoperatively, at discharge, and 3 months after discharge using Addenbrooke's Cognitive Examination version III (ACE-III). The primary endpoint was the ACE-III score at discharge. Increased MMP-12 and MBP concentrations were observed in the DEX group 24 and 72 h postoperatively. No significant differences in ACE-III scores were observed between the groups at discharge; however, the values were increased when compared with initial values after 3 months (p = 0.000). The current results indicate that the administration of dexmedetomidine as an adjuvant to anaesthesia can increase MMP-12 and MBP levels without effects on neurocognitive outcomes at discharge and 3 months postoperatively.

Neuroprotective Effect of Dexmedetomidine against Postoperative Cognitive Decline via NLRP3 Inflammasome Signaling Pathway

Dexmedetomidine (Dex), widely used as a sedative in surgical procedures and intensive care units, induces sympatholytic, anxiolytic, analgesic, and sedative effects. Postoperative cognitive dysfunction (POCD) is routinely observed in postoperative care following surgery and general anesthesia. The NLRP3 inflammasome complex plays a critical role in innate immune response by detecting pathogenic microorganisms and activating pro-inflammatory cytokines. Although there are numerous protective effects of Dex among the neurological diseases, specific mechanisms including NLRP3 inflammasome-mediated neuroinflammation via oxidative stress response in a POCD model are not fully understood. Here, we investigated whether Dex exhibits neurocognitive effects through the NLRP3 inflammasome signaling in a POCD mouse model using a neurobehavioral test and ELISA analysis. We also confirmed the level of oxidative stress-related response in the in vitro system in the POCD model. Furthermore, we evaluated the NLRP3 inflammasome complex by immunoprecipitation analysis. In summary, the results of the present study indicated that Dex showed a neuroprotective effect in the POCD model by reducing oxidative stress response through NLRP3 inflammasome-mediated neuroinflammation.

Different modalities of analgesia in open heart surgeries in Mansoura University

Background: Opioid usage in cardiac surgery is considered to be the corner stone in management. Inadequate pain control after cardiac surgery complicates patient recovery and increases the load on healthcare services. Multimodal analgesia can be used to achieve better analgesic effect and improves patient outcome.  Material and methods: A total of 90 patients undergoing cardiac surgery with median sternotomy were randomly allocated equally into three groups intraoperatively where first group received continuous infusion of high dose opioids, second group received boluses of low dose opioids and third group received multimodal non opioid analgesics including dexmedetomidine, ketamine and magnesium sulphate. All patients received the same post-operative analgesic regimen consists of morphine patient controlled analgesia (PCA). Results: Patients in multimodal non opioid group had more stable hemodynamics intra and postoperatively. Also, patients in multimodal group had lower pain scores extubation, earlier extubation, shorter ICU stay, earlier mobilization and earlier return of bowel movements compared to patients of both groups received intraoperative higher opioid doses.

The Protective Mechanism of Dexmedetomidine on Renal in Hemorrhagic Shock

Objective

To explore the protective effect of dexmedetomidine on renal function in patients with hemorrhagic shock and its possible mechanism.

Methods

Seventy patients with traumatic hemorrhagic shock requiring surgical treatment were randomly divided into the control group (group C) and the dexmedetomidine group (group D), with 35 patients in each group. Patients in both groups were actively treated with volumetric resuscitation while surgical hemostasis. Group D was given dexmedetomidine 0.5 μg/kg before skin incision after anesthesia induction, for 10 min, followed by intravenous infusion at a rate of 0.4 μg·kg⁻¹·h⁻¹ until 30 min before surgery, and group C was given equal volume of normal saline before skin resection (H1). Venous blood was collected 2 h (H2) and 4 h (H4) after skin resection, and plasma levels of BUN, creatinine (SCr), lipid peroxides (MDA), and inflammatory mediators IL-6 and IL-8 were measured on the 1st and 2nd day after surgery.

Results

Compared with H1, BUN and SCr levels had no significant difference at 2 h and 4 h after skin resection but significantly decreased at 1 and 2 postoperative days (D1) (P < 0.05). There were significant differences in MDA, IL-6, and IL-8 at 2 and 4 h after skin resection (P < 0.05), but there were no significant differences at 1 day after surgery (D1) and 2 days after surgery (D2). Compared with group C, the levels of MDA, IL-6, and IL-8 in group U were significantly decreased at 2 h and 4 h after skin resection (P < 0.05), and the levels of BUN and SCr in group U were significantly decreased at 1 and 2 days after skin resection (P < 0.05).

Conclusion

Dexmedetomidine can effectively inhibit the release of oxygen free radicals in the shock stage and the shock recovery stage in patients with hemorrhagic trauma shock and has a protective effect on renal function.

Effects of Intraoperative Dexmedetomidine Infusion on Postoperative Delirium in Elderly Patients Undergoing Total Hip Arthroplasty

Objective

To investigate the effects of dexmedetomidine on postoperative delirium in elderly patients undergoing total hip arthroplasty.

Methods

A total of 100 patients, 42 male and 58 female, ages 60 to 85 years, American Society of Anesthesiologists grade I or II, who were undergoing total hip arthroplasty were randomly divided into 2 groups: a dexmedetomidine group (group D; n = 50) and a control group (group C; n = 50). Group D patients were infused with 0.3 μg · kg−1 · h−1 of dexmedetomidine from 5 minutes prior to anesthesia induction until the end of surgery. Group C patients received an equal volume of saline. Heart rate and mean arterial pressure (MAP) were recorded before anesthesia induction (T0), 1 minute before extubation (T1), and 30 minutes after extubation (T2). The Visual Analog Score (VAS) at 1, 2, and 3 days after surgery, the incidence and duration of postoperative delirium, and the length of hospital stay were recorded. Adverse reactions, such as nausea, vomiting, and lethargy, were also recorded.

Results

The Visual Analog Scores in the 2 groups were similar. In group D, there was no significant difference in heart rate (P = 0.232) and MAP (P = 0.056) between T0 and T1. However, in group C, heart rate significantly increased by 15.3 bpm (P = 0.000) and MAP significantly increased by 10.7 mmHg (P = 0.001) at T1 compared with those at T0. The incidence of postoperative delirium in group D (10%) was significantly lower than that in group C (26%; P = 0.037). The duration of delirium in group D (1.3 ± 0.6 days) was shorter than that in group C (3.0 ± 0.5 days; P = 0.000). The length of hospital stay in group D (13.2 ± 0.9 days) was shorter than that in group C (16.1 ± 0.7 days; P = 0.000). No significant differences were observed in adverse effects between the 2 groups.

Conclusion

Intravenous infusion of dexmedetomidine can not only reduce the incidence and duration of postoperative delirium, but also shorten the length of hospital stay in elderly patients undergoing total hip arthroplasty.

Perioperative dexmedetomidine and 5-year survival in patients undergoing cardiac surgery

BACKGROUND

Dexmedetomidine sedation has been associated with favourable outcomes after surgery. We aimed to assess whether perioperative dexmedetomidine use is associated with improved survival after cardiac surgery.

METHODS

This retrospective cohort study included 2068 patients undergoing on-pump coronary artery bypass grafting and/or valve surgery. Among them, 1029 patients received dexmedetomidine, and 1039 patients did not. Intravenous dexmedetomidine infusion of 0.007 μg kg^-1 min^-1 was initiated before or immediately after cardiopulmonary bypass and lasted for < 24 h. The primary outcome was 5-year survival after cardiac surgery. The propensity scores matching (PSM), inverse probability of treatment weighting (IPTW), and overlap weighting approaches were used to minimise bias. Survival analyses were performed with Cox proportional-hazard models.

RESULTS

The median age was 63 yr old and the male to female ratio was 71:29 in both groups. Baseline covariates were balanced between groups after adjustment using PSM, IPTW, or overlap weighting. Patients receiving dexmedetomidine in cardiac surgical procedures had higher survival during postoperative 5 yr in unadjusted analysis (hazard ratio [HR]=0.63; 95% confidence interval [CI], 0.51-0.78; P<0.001), and after adjustment with PSM (HR=0.63; 95% CI, 0.45-0.89; P=0.009), IPTW (HR=0.70; 95% CI, 0.51-0.95; P=0.023), or overlap weighting (HR=0.67; 95% CI, 0.51-0.89; P=0.006). The 5-yr mortality rate after cardiac surgery was 13% and 20% in the dexmedetomidine and non-dexmedetomidine groups, respectively (PSM adjusted odds ratio=0.61; 95% CI, 0.42-0.89; P=0.010).

CONCLUSION

Perioperative dexmedetomidine infusion was associated with improved 5-yr survival in patients undergoing cardiac surgery.

The immunomodulatory mechanism of dexmedetomidine

Dexmedetomidine has been increasingly introduced into the perioperative care of surgical patients. Because a subset of anesthetics/sedatives are immunomodulatory, it is critical to understand the role of dexmedetomidine in our host immune functions. Here we reviewed the role of dexmedetomidine in different immune cells. We also reviewed published clinical articles that described the role of dexmedetomidine in organ injury, cancer surgery, and infection. In animal studies, dexmedetomidine attenuated organ injury. In clinical studies, dexmedetomidine was associated with an improvement in outcomes in cardiac surgery and transplant surgery. However, there is a paucity in research examining how dexmedetomidine is associated with these outcomes. Further studies are needed to understand its clinical application from immunological standpoints.

Cardioprotective effects of propofol-dexmedetomidine in open-heart surgery: A prospective double-blind study

Background:

Myocardial protection in cardiac surgeries is a must and requires multimodal approaches in perioperative period to decrease and prevent the increase of myocardial oxygen demand and consumption that lead to postoperative cardiac complications including myocardial ischemia, dysfunction, and heart failure.

Study Design:

Prospective, controlled, randomized, double-blinded study.

Aims:

This study aims to study the effect of propofol-dexmedetomidine continuous infusion cardioprotection during open-heart surgery in adult patients.

Materials and Methods:

Sixty adult patients of both sexes aged from 30 to 60 years old belonging to the American Society of Anesthesiologists III or IV undergoing open-heart surgery were randomly divided into two equal groups: Group P (control group) received continuous infusion of propofol at a rate of 2 mg/kg/h and 50 cc 0.9% sodium chloride solution infused at a rate of 0.4 μg/kg/h (used as a placebo) and Group PD received continuous infusion of propofol at a rate of 2 mg/kg/h and dexmedetomidine 200 μg diluted in 50 cc 0.9% sodium chloride solution infused at a rate of 0.4 μg/kg/h. Infusion for all patients started immediately preoperative till skin closure. Hemodynamic measurements of heart rate (HR), invasive mean arterial pressure, and oxygen saturation were recorded at baseline before induction of anesthesia, immediately after intubation, at skin incision, at sternotomy and every 15 min in the 1^st h then every 30 min during the prebypass period then every 15 min in the 1^st h then every 30 min after weaning from CPB till the end of the surgery. Serum biomarkers; cardiac troponin (cTnI) and creatine kinase-myocardial bound (CK-MB) samples were measured basally (T1), 15 min after unclamping of the aorta (T2), immediate postoperative (T3), and 24 h postoperative (T4). Intraoperative data were also recorded including the number of coronary grafts, aortic cross-clamping duration, duration of cardiopulmonary bypass (CPB), duration of surgery, and rhythm of reperfusion. Fentanyl requirement, extubation time, and length of intensive care unit (ICU) stay were also recorded for every case.

Results:

There was no statistically significant differences as regard to demographic data between the studied two groups. HR and blood pressure recorded was lower in the PD group than the control group, and this difference was noted to be statistically significant. Furthermore, the PD group showed lower levels of myocardial enzymes (cTnI and CK-MB), decreased total fentanyl requirement, earlier postoperative extubation, and shorter ICU stay than the P (control) group.

Conclusion:

The use of propofol-dexmedetomidine in CPB surgeries offers more cardioprotective effects than the use of propofol alone.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention

Postoperative delirium is a geriatric syndrome that manifests as changes in cognition, attention, and levels of consciousness after surgery. It occurs in up to 50% of patients after major surgery and is associated with adverse outcomes, including increased hospital length of stay, higher cost of care, higher rates of institutionalization after discharge, and higher rates of readmission. Furthermore, it is associated with functional decline and cognitive impairments after surgery. As the age and medical complexity of our surgical population increases, practitioners need the skills to identify and prevent delirium in this high-risk population. Because delirium is a common and consequential postoperative complication, there has been an abundance of recent research focused on delirium, conducted by clinicians from a variety of specialties. There have also been several reviews and recommendation statements; however, these have not been based on robust evidence. The Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together a team of multidisciplinary experts to formally survey and evaluate the literature on postoperative delirium prevention and provide evidence-based recommendations using an iterative Delphi process and Grading of Recommendations Assessment, Development and Evaluation (GRADE) Criteria for evaluating biomedical literature.

Dexmedetomidine's Relationship to Delirium in Patients Undergoing Cardiac Surgery: A Systematic Review

This systematic review aims to determine the relationship between postoperative delirium and the use of dexmedetomidine in comparison with commonly used sedatives/analgesics in the postoperative cardiac surgery patient. A systematic literature search of PubMed plus, CINAHL, Scopus, and Ovid, and limited to the English language in the last 10 years, was performed. Randomized controlled trials, observational and retrospective studies, and meta-analyses with at least 1 delirium assessment tool were included. The search found 196 potential articles; however, only 12 met the criteria outlined. The systematic review revealed a decrease in postoperative delirium for patients receiving dexmedetomidine in all studies. Seven studies demonstrated statistically significant reductions in postoperative delirium with dexmedetomidine compared with other sedatives/analgesics. One study also revealed reduction of delirium with dexmedetomidine as compared with normal saline. Two studies showed a delayed time to delirium onset in patients receiving dexmedetomidine versus propofol or morphine. The 2 meta-analyses found that all included studies had a statistically significant reduction in postoperative delirium when using dexmedetomidine. Postoperative use of dexmedetomidine in cardiac surgery patients may reduce the incidence of postoperative delirium.

Perioperative Dexmedetomidine Supplement Decreases Delirium Incidence After Adult Cardiac Surgery: A Randomized, Double-Blind, Controlled Study

OBJECTIVE

Conflicting data exist on the effect of dexmedetomidine on delirium. For the present study, a randomized trial was performed to investigate the effect of perioperative dexmedetomidine on the rate of postoperative delirium after cardiac surgery.

DESIGN

A randomized controlled trial.

SETTING

University hospital.

PARTICIPANTS

Patients (n = 169) undergoing elective cardiac surgery (coronary artery bypass graft surgery, valve surgery, or combined surgery) with cardiopulmonary bypass.

INTERVENTIONS

Patients received a sevoflurane-based general anesthesia and were randomly assigned 1:1 to receive a dexmedetomidine infusion that started in the operating room (0.7 μg/kg/h) and continued into the intensive care unit (0.4 μg/kg/h) or an equivolume infusion of placebo.

MEASUREMENTS AND MAIN RESULTS

A decrease in the rate of delirium in the dexmedetomidine group compared with the placebo group was demonstrated (6 of 84 [7.1%] v 16 of 85 [18.8%]; p = 0.02; odds ratio [OR] 0.33 [95% confidence interval {CI} 0.12-0.90]). Reduced intensive care unit and hospital lengths of stay also were observed (18 [18-22] hours v 22 [18-39] hours; p = 0.002 and 17 [7-20] days v 19 [8-21] days; p = 0.04, respectively). Mortality at 30 days was 2 (2.4%) in both groups. On multivariate analysis, only dexmedetomidine administration (OR 0.24 [95% CI 0.08-0.74]) and cardiopulmonary bypass time (OR 1.02 [95% CI 1.01-1.03] for increases of 1 min) were independent predictors of delirium development.

CONCLUSIONS

Dexmedetomidine administered during and after general anesthesia for cardiac surgery with cardiopulmonary bypass decreased the rate of postoperative delirium and intensive care unit and hospital lengths of stay.

Dexmedetomidine in Adult Patients in Cardiac Surgery Critical Care: An Evidence-Based Review

Although several options are available for postoperative sedation in the intensive care unit, the selective α2-adrenoceptor agonist dexmedetomidine may offer advantages for patients after cardiac surgery. The author conducted a review of the literature on the use of dexmedetomidine in the cardiac surgery population to determine possible advantages and disadvantages in this patient population. Although the use of dexmedetomidine has not been conclusively shown to change overall morbidity and mortality and may be associated with higher drug cost, its other demonstrated effects offer advantages for postoperative cardiac surgery patients that other forms of sedation cannot match.

Dexmedetomidine protects H9c2 cardiomyocytes against oxygen-glucose deprivation/reoxygenation-induced intracellular calcium overload and apoptosis through regulating FKBP12.6/RyR2 signaling

Purpose

Intracellular calcium ([Ca²⁺]i) overload is a major cause of cell injury during myocardial ischemia/reperfusion (I/R). Dexmedetomidine (DEX) has been shown to exert anti-inflammatory and organ protective effects. This study aimed to investigate whether pretreatment with DEX could protect H9c2 cardiomyocytes against oxygen-glucose deprivation/reoxygenation (OGD/R) injury through regulating the Ca²⁺ signaling.

Methods

H9c2 cardiomyocytes were subjected to OGD for 12 h, followed by 3 h of reoxygenation. DEX was administered 1 h prior to OGD/R. Cell viability, lactate dehydrogenase (LDH) release, level of [Ca²⁺]i, cell apoptosis, and the expression of 12.6-kd FK506-binding protein/ryanodine receptor 2 (FKBP12.6/RyR2) and caspase-3 were assessed.

Results

Cells exposed to OGD/R had decreased cell viability, increased LDH release, elevated [Ca²⁺]i level and apoptosis rate, down-regulated expression of FKBP12.6, and up-regulated expression of phosphorylated-Ser2814-RyR2 and cleaved caspase-3. Pretreatment with DEX significantly blocked the above-mentioned changes, alleviating the OGD/R-induced injury in H9c2 cells. Moreover, knockdown of FKBP12.6 by small interfering RNA abolished the protective effects of DEX.

Conclusion

This study indicates that DEX pretreatment protects the cardiomyocytes against OGD/R-induced injury by inhibiting [Ca²⁺]i overload and cell apoptosis via regulating the FKBP12.6/RyR2 signaling. DEX may be used for preventing cardiac I/R injury in the clinical settings.

Dexmedetomidine versus midazolam and propofol for sedation in critically ill patients: Mining the Medical Information Mart for Intensive Care data

Background

The benefits of dexmedetomidine on reducing mortality and length of intensive care unit (ICU) stay are still controversial. We aimed to evaluate the superiority of dexmedetomidine by comparing it with midazolam and propofol.

Methods

Subjects who were given dexmedetomidine, midazolam and propofol exclusively as sedatives in the Beth Israel Deaconess Medical Center between 2001 and 2012 were identified from the Medical Information Mart for Intensive Care (MIMIC) III database. Univariate, multivariate and stratified analysis was performed to compare the mortality and length of ICU stay between the dexmedetomidine, midazolam and propofol groups. To compare the depth of sedation between the midazolam and propofol group, we used propensity score matching (PSM) to create comparable units and their Richmond Agitation Sedation Score (RASS) were analyzed.

Results

A total of 1,542 unique ICU records were identified in the MIMIC-III database, among which 163 belonged to the dexmedetomidine group and 531 belonged to the midazolam group and 848 belonged to the propofol group. Mortality was decreased in dexmedetomidine group compared with midazolam group (OR 15.25; 95% CI, 5.29-64.80, P<0.001) and propofol group (OR 5.51; 95% CI, 1.91-23.45, P=0.006). In patients with high Simplified Acute Physiologic Score (SAPS) II (>52), midazolam was related to a higher mortality (~50%). But competing risk analysis revealed that dexmedetomidine was associated with longer ICU stay (P<0.001). There was no significant difference in the RASS between propofol and midazolam group (P=0.300).

Conclusions

Dexmedetomidine was significantly related to lower mortality when compared with midazolam and propofol. Midazolam had a comparably higher mortality than propofol and dexmedetomidine in patients with high SAPS II. Propofol and midazolam were equivalent in sedative efficacy. Further evaluation is needed.

Comparative Evaluation of Different Doses of Intravenous Dexmedetomidine on Hemodynamic Response during Laryngoscopy and Endotracheal Intubation in Geriatric Patients Undergoing Spine Surgeries: A Prospective, Double-Blind Study

BACKGROUND

Dexmedetomidine, a selective alpha 2 (α2)-adrenergic receptor agonist, has been used to blunt the hemodynamic response associated with laryngoscopy and tracheal intubation, which is a common concern for the anesthesiologist, especially in high-risk patients and geriatric age group.

AIM AND OBJECTIVES

The current study is to evaluate and compare the effects of different doses of dexmedetomidine in controlling hemodynamic response during tracheal intubation in geriatric patients.

MATERIALS AND METHODS

After getting approval from the Ethical Committee, 90 patients of the American Society of Anesthesiologist Physical Status Classes I and II, aged ≥60 years, were randomly assigned into three groups: Group I (normal saline, n = 30), Group II - dexmedetomidine (0.50 μg/kg, n = 30), and Group III - dexmedetomidine (1.00 μg/kg, n = 30). Dexmedetomidine was infused for 10 min before induction. Data were recorded as before infusion (T0), at the end of infusion (T1), before tracheal intubation (T2), at the moment of tracheal intubation (T3) 5 min after tracheal intubation (T4), and 10 min after tracheal intubation (T5). Modified observer's assessment of alertness/sedation scale score was observed at the time of T0 and T1. All statistical analyses were done using SPSS version 22.

RESULTS

Mean systolic blood pressure was statistically significantly (P < 0.05) more among Group I compared to Group II and III at T2, T3, and T4. Mean heart rate (HR) value was significantly (P < 0.05) more among Group I compared to Group III from T1 to T5, whereas there was no significant change in HR between Group I and Group II and at T4 and T5 h was comparable in Group II and Group III.

CONCLUSION

This study concluded that more acceptable hemodynamic changes were seen with 0.50 μg/kg dexmedetomidine when compared with 1.0 μg/kg dexmedetomidine during intubation. A lower dose besides being cost-effective is also free of side effects associated with the higher dose of 1 μg/kg dexmedetomidine.

Evaluating the use of dexmedetomidine for the reduction of delirium: An integrative review

Delirium, an acute change in cognition and attention not secondary to a pre-existing condition or dementia, affects nearly 40,000 hospitalized older adults in the United States every day. Delirium is associated with increased healthcare costs of $16,303 to $64,421 per patient. To date, no single pharmacological intervention is effective in preventing or treating delirium in critically ill patients. Evidence suggests the alpha-2 agonist, dexmedetomidine, may reduce or prevent delirium. An integrative review examined whether dexmedetomidine was associated with a lower incidence of delirium compared to other analgesic and sedation strategies. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guided this review and 16 publications met quality criteria for inclusion. These studies support that postoperative administration of dexmedetomidine may reduce delirium in patients, particularly following cardiac surgery. Further research is needed to determine the benefits of dexmedetomidine in patients on mechanical ventilation and optimal timing and duration of administration.

Pediatric Cardiac Surgery and Pain Management: After 40 Years in the Desert, Have We Reached the Promised Land?

Pain prevention in the pediatric population is mandatory and an integrative aspect of medical practice. Optimal pain management is the right of all patients and the responsibility of all health professionals. The key to adequate pain management is assessing its presence and severity, identifying those who require intervention, and appreciating treatment efficacy. The population of pediatric patients undergoing cardiac surgery is unique in both clinical severity and hemodynamic response to painful stimuli, thus making pain management even more challenging. In this review, we will describe the different pain assessment tools as well as intra- and postoperative regimens of pain management.

Therapeutic Efficacy of Two Different Doses of Dexmedetomidine on the Hemodynamic Response to Intubation, the Intubating Conditions, and the Effect on the Induction Dose of Propofol: A Randomized, Double-Blind, Placebo-Controlled Study

Context:

The hemodynamic response associated with laryngoscopy and tracheal intubation is a common concern for the anesthesiologist, especially in high-risk patients. The use of dexmedetomidine has found favor in obtunding this response, in addition to providing better intubating conditions and reducing the dose of other anesthetic drugs. Most of the current literature states a loading dose of 1 μg/kg dexmedetomidine to be superior to lower doses in this regard. However, using a lower dose may be advantageous by reducing incidence of adverse effects such as hypotension and bradycardia which are likelier with the use of higher dose, in addition to being more cost-effective.

Aims:

The aim of the study was (1) to evaluate and compare the effect of loading doses of 1 μg/kg and 0.5 μg/kg dexmedetomidine on attenuation of hemodynamic response to laryngoscopy and intubation and (2) to evaluate the efficacy of dexmedetomidine in reducing the induction dose of propofol for achieving better intubating conditions.

Materials and Methods:

A randomized, double-blind, placebo-controlled study was planned on ninety American Society of Anesthesiologists I and II patients scheduled for elective surgery under general anesthesia. Patients were divided into three groups. Two groups received different loading doses of dexmedetomidine infusion before induction and the third group was a control group. The induction dose of propofol required to abolish the verbal response was noted and compared in all the three groups. All patients were assessed for the intubating conditions and hemodynamic response.

Statistical Analysis:

Nonparametric data were compared using the Chi-square test and parametric data were compared using Student's t-test using SPSS 16.0 software.

Results:

Both the loading doses of 1 μg/kg and 0.5 μg/kg dexmedetomidine were equally effective in reducing the induction dose of propofol, improving the intubating conditions and blunting the hemodynamic response to laryngoscopy and intubation. The incidence of adverse effects such as hypotension and bradycardia was lesser with the loading dose of 0.5 μg/kg.

Conclusions:

Dexmedetomidine when used as infusion in the loading dose of 0.5 μg/kg is therapeutically as effective as when used in the dose of 1.0 μg/kg not only in reducing the induction dose of propofol but also in providing good intubating conditions and blunting the hemodynamic response to intubation. A lower dose is associated with a lesser incidence of adverse effects such as hypotension and bradycardia.

Use of Dexmedetomidine in Cardiothoracic and Vascular Anesthesia

Dexmedetomidine is a highly selective α₂-adrenergic agonist with analgesic and sedative properties. In the United States, the Food and Drug Administration approved the use of the drug for short-lasting sedation (24 h) in intensive care units (ICUs) in patients undergoing mechanical ventilation and endotracheal intubation. In October 2008, the Food and Drug Administration extended use of the drug for the sedation of nonintubated patients before and during surgical and nonsurgical procedures. In the European Union, the European Medicine Agency approved the use of dexmedetomidine in September 2011 with a single recognized indication: ICU adult patients requiring mild sedation and awakening in response to verbal stimulus. At present, the use of dexmedetomidine for sedation outside the ICU remains an off-label indication. The benefits of dexmedetomidine in critically ill patients and in cardiac, electrophysiology-related, vascular, and thoracic procedures are discussed.

Comparison of the cardioprotective effects of dexmedetomidineand remifentanil in cardiac surgery

Background/aim: Myocardial protection is an important factor of open heart surgery and biological biomarkers (lactate, CKMB, cardiac troponin I, and pyruvate) are used to assess myocardial damage. This study compares the effects of dexmedetomidine and remifentanil on myocardial protection during coronary artery bypass grafting (CABG) surgery. Materials and methods: Patients scheduled for elective CABG surgery (n = 60) were included in this study. Anesthesia induction was introduced with propofol, fentanyl, and vecuronium bromide. Anesthesia was maintained with remifentanil infusion and sevoflurane in the remifentanil group (Group R) and with dexmedetomidine infusion and sevoflurane in the dexmedetomidine group (Group D). Blood samples for biochemical markers were taken from the coronary sinus catheter before cardiopulmonary bypass (T1), 20 min after aortic cross-clamping (T2), 20 min after removal of the aortic cross-clamping (T3), and 10 min after separation from cardiopulmonary bypass (T4).Results: Demographic data were similar between the groups. Lactate level at the T2 period and CKMB levels during the study period were lower in Group D than in Group R. In both groups, all values except pyruvate significantly increased over time. Conclusion: The dexmedetomidine-sevoflurane combination may improve the cardioprotective effect in comparison with remifentanil-sevoflurane in CABG surgery.

Effects of dexmedetomidine on heart arrhythmia prevention in off-pump coronary artery bypass surgery: A randomized clinical trial

Background

Arrhythmia occurring during and after surgery is one of the major complications in open-heart surgery. Dexmedetomidine is an intravenous alpha-2 agonist and very specific short-acting drug to protect the various organs against ischemic injuries and blood reflow. However, the effect of dexmedetomidine for preventing intraoperative heart arrhythmias has not been recognized.

Objective

This study aimed to determine the effect of dexmedetomidine on the incidence rate of heart arrhythmias and anesthetic required in off-pump coronary artery bypass surgery.

Methods

This randomized clinical trial was conducted on patients who were candidates for off-pump coronary artery bypass referring to Imam Reza Hospital of Mashhad, Iran, from July 2016 through January 2017. The patients were randomly assigned to two groups of intervention (infusion of 0.5 mcg/kg/h dexmedetomidine together with induction followed by infusion of 0.5 mcg/kg/h by the end of the surgery) or control (saline infusion). Mean arterial pressure (MAP) and heart rate (HR) were measured before induction, during surgery operation and ICU admission. Data were analyzed by SPSS version 18 using Chi Square and independent-samples t-test.

Results

A total of 76 patients with a mean age of 59.8 ± 8.2 years (in two groups of 38) were studied. The two groups had no statistically significant difference in terms of background variables. The MAP and HR values before induction, during surgery and ICU admission were significantly higher in the control group than in the intervention group (p=0.001). Out of the studied arrhythmias, the values of PAC (55.2% vs. 15.7%), PVC (81.5% vs. 21.0%), AF (26.3% vs. 7.8%), VTAC (21.0% vs. 2.6%) were significantly lower in dexmedetomidine group (p=0.001).

Conclusion

It seems that dexmedetomidine administration during induction and surgery can cause significant reduction in most of the common arrhythmias in off-pump coronary bypass surgery. The use of dexmedetomidine maintains MAP and HR at significantly lower values, and changes compared to the control group as well as reduces the need for anesthetic compounds.

Trial Registration

The present study has been registered at the Iranian Registry of Clinical Trials (www.IRCT.IR) with a code of IRCT2016072413159N9 before starting the study.

Founding

This study was fully sponsored by the Research Deputy at Mashhad University of Medical Sciences, Iran (grant number 941413).

Dexmedetomidine attenuates hypoxia/reoxygenation injury in primary neonatal rat cardiomyocytes

Systemic administration of dexmedetomidine provides cardioprotection against ischemia/reperfusion (I/R) injury; however, the direct effects of dexmedetomidine on cardiomyocytes have not been clarified. The present study investigated the effects of dexmedetomidine on primary neonatal rat cardiomyocytes under hypoxic/reoxygenation (H/R) conditions. In order to simulate in vivo I/R injury, primary neonatal rat cardiomyocytes were cultured under hypoxic conditions for 1 h and subsequently reoxygenated for 24 h. The effects of preconditioning with dexmedetomidine 2 h before hypoxia and postconditioning during reoxygenation were also examined. Cellular viability and activity were analyzed by monitoring the dynamic response profile of living cells using a real-time cell analyzer system. A special scaled index, defined as the normalized cell index (NCI), was used to minimize the influence of inter-experimental variations. The dose-effect curve was generated from the area under the time-course curve values of NCI. H/R exposure markedly decreased cell viability and activity. Furthermore, no cytotoxicity was associated with a clinically relevant concentration of dexmedetomidine. Preconditioning with dexmedetomidine concentration-dependently ameliorated the reductions in NCI in cardiomyocytes following H/R injury. Additionally, postconditioning with dexmedetomidine improved the reductions in NCI at concentrations between 3 and 200 nM. Finally, the effect of 3–40 nM dexmedetomidine postconditioning was greater than preconditioning. These results indicated that preconditioning and postconditioning with dexmedetomidine attenuated H/R injury in primary neonatal rat cardiomyocytes at the cellular level.

Myocardial protective effects of dexmedetomidine in patients undergoing cardiac surgery: A meta-analysis and systematic review

Arrhythmias are the common complications following cardiac surgery and contribute to hemodynamic instability, cognitive impairment, thromboembolic events, and congestive heart failure. Prevention of atrial fibrillation following cardiac surgery reduces morbidity and among the many available preventive approaches dexmedetomidine shows many positive effects on cardiovascular stability. Even though many studies indicated the beneficial effects of dexmedetomidine, the power of the analysis and conclusion of these studies is rather weak due to relatively smaller number of patients in these studies. In the present meta-analysis, we included a large number of patients, both children and adults, undergoing cardiac surgery, to address the efficacy of dexmedetomidine. Several databases were searched to identify clinical studies comparing the efficacy of dexmedetomidine in myocardial protection in patients undergoing cardiac surgery. Cardiac function related parameters including heart rate, blood pressure, tachycardia, arrhthmias, and bradycardia were measured. In accordance with the selection criteria, a total of 18 studies published between 2003 and 2016, with a total of 19,225 patients were included in the present meta-analysis. Dosage of dexmedetomidine was in the range of 0.5-1 µg/kg body weight loading followed by continuous infusion at a rate of 0.2-0.7 µg/kg/h. Dexmedetomidine treatment was found to lower heart rate, systolic blood pressure, incidence of tachycardia and arrhythmias in both adult and pediatric patients, but elevated the risk of bradycardia. In conclusion, results of this meta-analysis indicate that dexmedetomidine is an efficacious cardioprotective drug in adults and children undergoing cardiac surgery.

Intraoperative use of dexmedetomidine is associated with decreased overall survival after lung cancer surgery

Background and Aims:

The aim is to evaluate the association between the use of intraoperative dexmedetomidine with an increase in recurrence-free survival (RFS) and overall survival (OS) after nonsmall cell lung cancer (NSCLC) surgery.

Material and Methods:

This was a propensity score-matched (PSM) retrospective study. Single academic center. The study comprised patients with Stage I through IIIa NSCLC. Patients were excluded if they were younger than 18 years. Primary outcomes of the study were RFS and OS. RFS and OS were evaluated using univariate and multivariate Cox proportional hazards models after PSM (n = 251/group) to assess the association between intraoperative dexmedetomidine use and the primary outcomes. The value of P < 0.05 was considered statistically significant.

Results:

After PSM and adjusting for significant covariates, the multivariate analysis demonstrated no association between the use of dexmedetomidine and RFS (hazard ratio [HR] [95% confidence interval (CI)]: HR = 1.18, 95% CI: 0.91–1.53; P = 0.199). The multivariate analysis also demonstrated an association between the administration of dexmedetomidine and reduced OS (HR = 1.28, 95% CI: 1.03–1.59; P = 0.024).

Conclusions:

This study demonstrated that the intraoperative use of dexmedetomidine to NSCLC patients was not associated with a significant impact on RFS and but worsening OS. A randomized controlled study should be conducted to confirm the results of this study.

Effect of perioperative dexmedetomidine on the endocrine modulators of stress response: a meta-analysis

This study examined the effects of perioperative dexmedetomidine treatment on physiological modulators of surgical stress response. The quality of the included studies was assessed prior to performing meta-analyses of the weighted mean differences in the changes from baseline of stress hormones and interpreted in the light of statistical heterogeneity between the studies. Nineteen studies (844 surgical subjects) data were used for this meta-analysis. Dexmedetomidine administration significantly decreased blood cortisol levels (μg/dL) postoperatively (mean difference with 95% confidence interval (CI) from controls: -18.78 (-28.45, -9.10); P < 0.05). In the subgroup analysis, the mean difference between dexmedetomidine-treated and saline-treated subjects in the changes from baseline of the cortisol levels was -20.10 (-30.96, -9.25; P < 0.05) but, between dexmedetomidine- and comparator-treated subjects, it was not statistically significantly different (-15.13 (-49.78, 19.52); P < 0.05). Compared with controls, dexmedetomidine treatment also decreased adrenaline and noradrenaline levels significantly (mean difference in the percent changes from baseline: -90.41 (-145.79, -35.03)%; P < 0.05 and -62.82 (-85.47, -0.40.17)%; P < 0.05, respectively). Dexmedetomidine also decreased prolactin levels with a mean difference of -19.42 (-39.37, 0.52) μg/L (P = 0.06). In conclusion, perioperative use of dexmedetomidine reduces serum catecholamine and cortisol levels but the decrease in cortisol levels was not statistically different from the comparator anaesthetics. More data will be required to assess the effects of dexmedetomidine on corticotropin, prolactin, and growth hormone.

Predicting, preventing, and identifying delirium after cardiac surgery

Delirium after cardiac surgery is a major problem. The exact mechanisms behind delirium are not understood. Potential pathways of delirium include neurotransmitter interference, global cognitive disorder, and neuroinflammation. Several predisposing and precipitating risk factors have been identified for postoperative delirium. The development of delirium following cardiac surgery is associated with worse outcomes in the perioperative period. Multiple interventions are being explored for the prevention and treatment of delirium. Studies investigating the potential roles of biomarkers in delirium as well as pharmacological interventions to reduce the incidence and duration of delirium are necessary to mitigate this negative outcome.

The Effect of Dexmedetomidine on Outcomes of Cardiac Surgery in Elderly Patients

OBJECTIVE

The goal of this retrospective study was to investigate the effects of perioperative use of dexmedetomidine (Dex) on outcomes for older patients undergoing cardiac surgery.

DESIGN

Retrospective investigation.

SETTING

Patients from a single tertiary medical center.

PARTICIPANTS

A total of 505 patients (≥65 years old) who underwent coronary artery bypass graft (CABG) or valve surgery. CABG and/or valve surgery plus other procedures were divided into 2 groups: 283 received intravenous Dex infusion (Dex group) and 222 did not (Non-Dex group).

INTERVENTIONS

Perioperative Dex intravenous infusion (0.24 to 0.6 μg/kg/h) initiated after cardiopulmonary bypass and continued for<24 hours postoperatively in the ICU.

MEASUREMENTS AND MAIN RESULTS

Data were risk adjusted, propensity score weighted, and multivariate logistic regression was used. The primary outcome was mortality. Secondary outcomes included postoperative stroke, coma, myocardial infarction, heart block, cardiac arrest, delirium, renal failure, and sepsis. Perioperative Dex infusion significantly decreased in-hospital mortality (0.90% v 2.83%; adjusted odds ratio (OR), 0.099; 95% confidence interval (CI), 0.030-0.324; p = 0.004) and operative mortality (1.35% v 3.18%; adjusted OR, 0.251; 95% CI, 0.077-0.813; p = 0.021). Perioperative Dex treatment also reduced the risk of stroke (0.90% v 1.77%; adjusted OR, 0.15; 95% CI, 0.038-0.590; p = 0.007), and delirium (7.21% v 10.95%; adjusted OR, 0.35; 95% CI, 0.212-0.578; p < 0.0001).

CONCLUSIONS

Results from this study (ClinicalTrials.gov identifier: NCT01683448) suggested perioperative use of dexmedetomidine was associated with decreases in in-hospital and operative mortality in elderly patients following cardiac surgery. It also reduced incidences of postoperative stroke and delirium in elderly patients.

Outcomes of dexmedetomidine treatment in pediatric patients undergoing congenital heart disease surgery: a meta-analysis

BACKGROUND

Dexmedetomidine decreases cardiac complications in adults undergoing cardiovascular surgery. This systematic review assessed whether perioperative dexmedetomidine improves congenital heart disease (CHD) surgery outcomes in children.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched for randomized controlled trials (RCTs) or observational studies that were published until 16 April 2015 and compared dexmedetomidine with placebo or an alternative anesthetic agent during pediatric CHD surgery. The assessed outcomes included hemodynamics, ventilation length, intensive care unit (ICU) and hospital stays, blood glucose and serum cortisol levels, postoperative analgesia requirements, and postoperative delirium.

RESULTS

Five RCTs and nine observational studies involving 2229 patients were included. In pooled analyses, dexmedetomidine was associated with shorter length of mechanical ventilation (mean difference: -93.36, 95% CI: -137.45, -49.27), lower postoperative fentanyl (mean difference: -24.11, 95% CI: -36.98, -11.24) and morphine (mean difference: -0.07, 95% CI: -0.14, 0.00) requirements, reduced stress response (i.e., lower blood glucose and serum cortisol levels), and lower risk of delirium (OR: 0.39, 95% CI: 0.21, 0.74). The hemodynamics of dexmedetomidine-treated patients appeared more stable, but there were no significant differences in the ICU or hospital stay durations. Dexmedetomidine may increase the bradycardia and hypotension risk (OR: 3.14, 95% CI: 1.47, 6.69).

CONCLUSIONS

Current evidence indicates that dexmedetomidine improves outcomes in children undergoing CHD surgery. However, this finding largely relies on data from observational studies; high-quality RCTs are warranted because of the potential for subject selection bias.

The Effects of Dexmedetomidine on Myocardial Function Assessed by Tissue Doppler Echocardiography During General Anesthesia in Patients With Diastolic Dysfunction: A CONSORT-Prospective, Randomized, Controlled Trial

Dexmedetomidine is a commonly used sedative and adjuvant agent to general anesthesia. The present was designed to evaluate the effects of dexmedetomidine on myocardial function by using tissue Doppler echocardiography during general anesthesia in patients with diastolic dysfunction.Forty patients undergoing orthostatic surgery with ejection fraction preserved diastolic dysfunction grade 2 or 3 were randomly allocated to the Control and Dex group (n = 20, each). In the Dex group, dexmedetomidine was given as an initial loading dose of 1.0 μg/kg over 10 minutes followed by a maintenance dose of 0.5 μg/kg/h. The ratio of peak early diastolic transmitral or transtricuspid inflow velocity to early diastolic mitral or tricuspid annular velocity (LV or RV E/e') and left or right ventricular myocardial performance index (LV or RV MPI) were measured at before and after the administration dexmedetomidine or saline.The Dex group showed significant decrease of heart rate (P = 0.038), and increase of mean blood pressure (P < 0.001), LV E/e' (P = 0.025), and LV MPI (P < 0.001) compared to those of the Control group on a linear mixed model analysis. Also, the Dex group showed significant increase of RV E/e' (P < 0.001) and RV MPI (P = 0.028) compared to those of the Control group.Intraoperative dexmedetomidine administration during general anesthesia was appeared to deteriorate biventricular function in patients with diastolic dysfunction. We suggest careful consideration and a need for reducing dosage when administrating dexmedetomidine in patients with diastolic dysfunction.

Cardiac and renal protective effects of dexmedetomidine in cardiac surgeries: A randomized controlled trial

BACKGROUND

Cardiac and renal injuries are common insults after cardiac surgeries that contribute to perioperative morbidity and mortality. Dexmedetomidine has been shown to protect several organs against ischemia/reperfusion-(I/R) induced injury. We performed a randomized controlled trial to assess the effect of dexmedetomidine on cardiac and renal I/R injury in patients undergoing cardiac surgeries.

MATERIALS AND METHODS

Fifty patients scheduled for elective cardiac surgeries were randomized to dexmedetomidine group that received a continuous infusion of dexmedetomidine initiated 5 min before cardiopulmonary bypass (1 μg/kg over 15 min, followed by 0.5 μg/kg/h) until 6 h after surgery, whereas the control group received an equivalent volume of physiological saline. Primary outcome measures included myocardial-specific proteins (troponin-I, creatine kinase-MB), urinary-specific kidney proteins (N-acetyl-beta-D-glucosaminidase, alpha-1-microglobulin, glutathione transferase-pi, glutathione transferase alpha), serum proinflammatory cytokines (tumor necrosis factor alpha and interleukin-1 beta), norepinephrine, and cortisol levels. They were measured within 5 min of starting anesthesia (T₀), at the end of surgery (T₁), 12 h after surgery (T₂), 24 h after surgery (T₃), 36 h postoperatively (T₄), and 48 h postoperatively (T₅). Furthermore, creatinine clearance and serum cystatin C were measured before starting surgery as a baseline, and at days 1, 4, 7 after surgery.

RESULTS

Dexmedetomidine reduced cardiac and renal injury as evidenced by lower concentration of myocardial-specific proteins, kidney-specific urinary proteins, and pro-inflammatory cytokines. Moreover, it caused higher creatinine clearance and lower serum cystatin C.

CONCLUSION

Dexmedetomidine provided cardiac and renal protection during cardiac surgery.

Dexmedetomidine-fentanyl Compared With Midazolam-fentanyl for Conscious Sedation in Patients Undergoing Lumbar Disc Surgery

PURPOSE

Patients undergoing awake lumbar disc surgery need adequate sedation and analgesia. This study investigated whether use of a dexmedetomidine-fentanyl (DF) regimen could be superior to midazolam-fentanyl (MF) for these patients.

METHODS

Sixty patients scheduled for elective lumbar laminotomy and discectomy were randomly assigned to receive either DF or MF for conscious sedation. Patient-controlled intravenous analgesia with fentanyl was used for postoperative pain management. Hemodynamic and respiratory changes, sedation scores, pain scores, fentanyl consumption, patient satisfaction, postoperative hospital stay, and adverse events were assessed.

FINDINGS

The patient and surgical characteristics, sedation levels, and pain scores were similar in the 2 groups. Compared with the MF group, heart rate was lower in the DF group at six time points from skin incision to 15 minutes in the postanesthesia care unit (PACU), they are skin incision, 15 min after the beginning of surgery, 30 min after the beginning of surgery, skin closure, entering PACU, and 15 min in PACU (P = 0.016, 0.002, 0.000, 0.000, 0.000, and 0.001, respectively), whereas pulse oxygen saturation was higher at 3 time points from 15 minutes after the beginning of surgery to skin closure (P = 0.022, 0.026, and 0.025, respectively). The intraoperative, postoperative, and total consumption of fentanyl were lower in the DF group (total: mean difference = -69.3 µg; 95% CI, = -114.3 to -24.4; P = 0.003). No significant differences were found for adverse events, postoperative hospital stay, or satisfaction between the 2 groups.

IMPLICATIONS

Although awake lumbar disc surgery can be performed successfully under sedation with either MF or DF combination, the latter may be a better alternative because of less consumption of opioid analgesics. ChiCTR.org identifier: ChiCTR-TRC-13003645.

Postoperative Critical Care of the Adult Cardiac Surgical Patient. Part I: Routine Postoperative Care

OBJECTIVES

Cardiac surgery, including coronary artery bypass, cardiac valve, and aortic procedures, is among the most common surgical procedures performed in the United States. Successful outcomes after cardiac surgery depend on optimum postoperative critical care. The cardiac intensivist must have a comprehensive understanding of cardiopulmonary physiology and the sequelae of cardiopulmonary bypass. In this concise review, targeted at intensivists and surgeons, we discuss the routine management of the postoperative cardiac surgical patient.

DATA SOURCE AND SYNTHESIS

Narrative review of relevant English-language peer-reviewed medical literature.

CONCLUSIONS

Critical care of the cardiac surgical patient is a complex and dynamic endeavor. Adequate fluid resuscitation, appropriate inotropic support, attention to rewarming, and ventilator management are key components. Patient safety is enhanced by experienced personnel, a structured handover between the operating room and ICU teams, and appropriate transfusion strategies.

Anti-inflammatory Effects of Perioperative Dexmedetomidine Administered as an Adjunct to General Anesthesia: A Meta-analysis

The aim of this meta-analysis is to examine the effects of dexmedetomidine on serum inflammatory markers when administered perioperatively. We searched multiple electronic databases for relevant research papers, and carried out meta-analyses of weighted mean differences and interpreted in the light of statistical heterogeneity (I²). Fifteen RCTs recruiting 641 patients were included. Dexmedetomidine treatment significantly decreased interleukin-6 (IL-6), IL-8 and tumor necrosis factor-alpha (TNF-α) levels with mean differences [95% CI] in the changes from baseline between dexmedetomidine treated and controls of −25.14 [−35.29, −15.00]; P < 0.00001 (for IL-6), −5.69 [−10.77, −0.60]; P < 0.04 (for IL-8), and −20.30 [−30.93, −9.67]; P < 0.0002 (for TNF-α) immediately after surgery; and −41.55 [−57.41, −25.70]; P < 0.00001 (IL-6), −6.46 [−10.83, −2.08]; P < 0.005 (IL-8), and −14.67 [−22.61, −6.73]; P < 0.0003 (TNF-α) on postoperative day 1 (random effects). IL-10 levels were found to increase significantly a day after surgery (8.33 [3.31, 13.36]; P = 0.001). Subgroup analyses did not reveal significant differences. In conclusion, perioperative adjunctive use of dexmedetomidine substantially decreases serum IL-6, IL-8 and TNF-α levels.