Dexmedetomidine and cardiac protection for non‐cardiac surgery: a meta‐analysis of randomised controlled trials

Abstract

SummaryWe conducted a systematic review of the effects of dexmedetomidine on cardiac outcomes following non-cardiac surgery. We included prospective, randomised peri-operative studies of dexmedetomidine that reported mortality, cardiac morbidity or adverse drug events. A PubMed Central and EMBASE search was conducted up to July 2007. The reference lists of identified papers were examined for further trials. Of 425 studies identified, 20 were included in the metaanalysis (840 patients). Dexmedetomidine was associated with a trend towards improved cardiac outcomes; all-cause mortality (OR 0.27, 95% CI 0.01-7.13, p = 0.44), non-fatal myocardial infarction (OR 0.26, 95% CI 0.04-1.60, p = 0.14), and myocardial ischaemia (OR 0.65, 95% CI 0.26-1.63, p = 0.36). Peri-operative hypotension (26%, OR 3.80, 95% CI 1.91-7.54, p = 0.0001) and bradycardia (17%, OR 5.45, 95% CI 2.98-9.95, p < 0.00001) were significantly increased. An anticholinergic did not reduce the incidence of bradycardia (p = 0.43). A randomised placebocontrolled trial of dexmedetomidine is warranted. Major peri-operative cardiac events (cardiac death, nonfatal myocardial infarction and non-fatal cardiac arrest) have been reported in 1.4% of unselected patients undergoing elective non-cardiac surgery [1,2] and between 2.6 and 5.8% in selected patients considered to be at risk of cardiac disease [1]. Peri-operative cardiac events are approximately evenly distributed between myocardial oxygen supply demand imbalance and plaque rupture [3,4]. In addition, these cardiac events may be precipitated by a number of potential triggers in the perioperative period, including inflammation, surgical stress, hypercoagulable states and peri-operative hypoxic episodes [1]. It has therefore been estimated that, at best, a single medical therapy could be expected to result in a relative risk reduction of 20-35% for the composite endpoint of cardiac death, non-fatal myocardial infarction and non-fatal cardiac arrest in the peri-operative period [2].There has been considerable interest in the utility of adrenergic antagonists in decreasing peri-operative cardiac events. Beta-adrenergic antagonists decrease peri-operative myocardial ischaemia, although it is controversial whether this results in an improved cardiac outcome [5,6]. In addition, beta-adrenergic antagonists significantly increase the incidence of drug-associated hypotension and bradycardia which require treatment [6]. It is unclear whether these side-effects adversely affect the cardioprotective efficacy of peri-operative beta-blockade.Unfortunately, some patients may not realise the potential cardioprotective benefits of peri-operative beta-blockade, as this may be either contra-indicated or difficult to initiate in the peri-operative period in patients with active bronchospasm, conduction disorders or decompensated cardiac failure. Alpha-2 agonists may be an alternative anti-adrenergic therapy in these patients. Alpha-2 agonists decrease central noradrenergic activity of the locus coeruleus [7] with a decrease in...

Effect of dexmedetomidine infusion on N-terminal pro-B-type natriuretic peptide level in patients with femoral shaft fractures under general anesthesia

“…They found that both pre and postoperative BNP concentrations are predictors of MACE in patients undergoing elective prosthesis orthopedic surgery (Vetrugno et al, 2014). In our study, we showed that in the D group, the rise of NT-pro-BNP was less than in the control group, which is in agreement with the survey (Biccard et al, 2008). Mizrak et al evaluated the effect of DEX on intraoperative blood loss in pediatric adenotonsillectomy and they concluded that dexmedetomidine slightly increased bleeding during the operation (Mizrak et al, 2013).…”

Intraoperative hypernatremia and polyuric syndrome induced by dexmedetomidine

“…A clinical study found 17 % of non-cardiac surgery patients received dexmedetomidine preoperatively or intraoperatively between 2007 and 2008 [7]. In a meta-analysis, dexmedetomidine improved surgical outcomes by reducing all-cause mortality, non-fatal MI, and myocardial ischemia in patients undergoing non-cardiac surgeries [3]. However, attention must also been paid to the adverse reactions of dexmedetomidine.…”

“…However, attention must also been paid to the adverse reactions of dexmedetomidine. In addition to hypotension and bradycardia, urine output increase following dexmedetomidine use has been reported in the perioperative period [3,8].…”

“…Dexmedetomidine, a highly selective, short-acting intravenous alpha-2 agonist, has been used as a component of anesthetics due to its imidazoline receptor affinity, which provides analgesic, anxiolytic, and antinociceptive effects without respiratory depression [2]. Hypotension and bradycardia are the common adverse reactions to this agent [3]. In an animal model involving general anesthesia, dexmedetomidine increased urinary output while decreasing urine osmolality and increasing free water clearance.…”

Response: Does Perioperative Dexmedetomidine Improve Mortality after Coronary Artery Bypass Surgery?

“…Studies have demonstrated the effectiveness of dexmedetomidine as a stresssuppressing, anti-inflammatory, and anti-I/R injury agent in the prevention and treatment of cardiovascular events. [3][4][5] Catecholamines potentially may exacerbate myocardial injury and cause perioperative myocardial ischemia, which has been shown to increase the risk of postoperative mortality. Therefore, reducing the incidence of perioperative myocardial ischemia reduces the mortality by blunting the sympatheticadrenal-axis response through decreasing central sympathetic activity at the locus ceruleus.…”