Esmolol Research Articles

Efficacy of ultrasound-guided lower extremity nerve block combined with general anesthesia with laryngeal mask airway in patients undergoing total knee arthroplasty

Objective To evaluate the efficacy of uhrasound-guided lower extremity nerve block combined with general anesthesia with laryngeal mask airway in patients undergoing total knee arthroplasty.Methods Forty ASA Ⅰ-Ⅲ patients of both sexes,aged 52-80 yr,weighing 67-94 kg,undergoing total knee arthroplasty under general anesthesia,were randomly divided into 2 groups(n=20 each).Group Ⅰ received combined intravenous-inhalational anesthesia with endotracheal tube.Group Ⅱ received lower extremity nerve block guided by ultrasound and then combined intravenous-inhalational anesthesia with laryngeal mask airway.HR was maintained at 50-100bpm,MAP was maintained at the preoperative baseline level(increase or decrease amplitude<20%of the baseline level)during operation and in pestanesthesia care unit(PACU)and vasoaetive drugs(atropine,esmolol,efedrina,urapidil or labetalol)were given when necessary.The patients received patient-controlled intravenous analgesia with tramedol and lornoxicam(background infusion 2 ml/h,bolus dose 1 ml,lockout interval 15 min)after operation and VAS score was maintained at≤2.The requirement for vasoactive drugs during operation and in PACU,PACU stay length,and consumption of analgesics and occurrence of nausea and vomiting within 24 h after operation were recorded.Results Compared with group Ⅰ,the requirement for all vasoaetive drugs during operation and for esmolol,urapidil and labetalol in PACU was significantly reduced,PACU stay length Was significantly shortened,and the consumption of analgesics and incidence of nausea and vomiting were significantly reduced in group Ⅱ(P<0.01).Conclusion Ultrasound-guided lower extremity nerve block combined with general anesthesia with laryngeal mask airway provides better emcacy with fewer complications and less consumption of postoperative analgesics than general anesthesia with endotracheal tube in patients undergoing total knee arthroplasty. Key words: Ultrasonography; Nerve block; Laryngeal masks; Anesthesia,general; Arthroplasty,replacement,knee

Synthesis and evaluation of esmolol prodrugs for transdermal delivery

Esmolol hydrochloride, an important anti-hypertensive and anti-arrhythmic agent, is administered as intravenous infusion only. The objective of the present work is to screen the feasibility of this drug for transdermal delivery. To enhance the lipophilicity, a pro-drug approach was adopted. Four pro-drugs, esmolol acetate, propionate, butyrate, and valerate, were synthesized and characterized by IR, NMR, Mass spectroscopy, and elemental analysis. Physicochemical parameters were ascertained and in vitro skin permeability study was carried out using excised porcine skin. Drug and pro-drugs were assessed for anti-hypertensive effect on male Sprague Dawley rats and data was statistically analyzed by one-way ANOVA. The results indicate that esters had much higher lipophilicity (p < 0.001) than the parent drug. All the esters had recorded significantly higher (p < 0.001) skin permeability than the parent moiety, with esmolol valerate showing the highest steady state flux (1.899 ± 0.035 µmol/cm2/h). Esters showed greater reduction of blood pressure than the parent drug, with esmolol propionate showing the highest efficacy. The findings suggest that esterification can be a promising tool for enhancing the skin permeability of esmolol, which is an essential requirement for transdermal development.

Effect of psychological care on changes in auditory evoked potential and hemodynamics during anesthetic induction with remifentanil

Objective To explore psychological care on changes in auditory evoked potential (AEP) and hemodynamics during anesthetic induction with remifentanil. Methods 30 ASA Ⅰ-Ⅱ patients were divided into study group and conrol group. The study group received psychological care one day before surgery, a intravenous injection of remifentanil of 1μg/kg 4 min before anaesthestic induction, and then a continuous infusion of remifentanil 0.1 μg/kg/min, which was decreased to 0.05μg/kg/min during anesthetic induction; while the control group received esmolol of 300μg/kg/min, which was reduced to 200 μg/kg/min during induction. The medications were terminated 10 min after intubation. AEP, ECC, HR, SBP, and RPP were compared between the two groups and then analyzed statistically. Results AEP did not differ significantly between the two groups at different time points (P>0.05). SBP, HR, and RPP changed slightly in the study group after intubation. Conclusions Psychological care is helpful in making remifentanil more effectively suppress the adverse cardiovascular reactions during intubation. Key words: Remifentanil; Tracheal intubation; Vecuronium bromide; Fentanil; Haemodynamics; Psychological care

Effect of different dosage esmolol on inhibit endobronchial intubated cardiovascular response

Objective To study the suitable dosage and clinical efficacy of esmolol on inhibiting endobronchial intubated cardiovascular response. Methods Sixty ASA Ⅰ～Ⅱ patients who undergoing thoracic surgery were randomly allocated to one of three groups(20 per group)to receive:0.9% sodium chloride 10 ml (groupA), esmolol 0.5 mg/kg( group B), esmolol 1 mg/kg( groupC ). The systolic blood pressure (SBP), diastolic blood pressure(DBP) and heart rate(HR) were recorded and rate-pressure product(RPP) were calculated before induction(baseline) ,2 min after induction, and at instantly ,2 min ,5 min and 10 min after intubation. Results SBP, DBP, HR, RPP were significantly decreased 2 min after induction of anesthesia as compared to the baseline values in all 3 groups( P ＜ 0.05 ), while immediately after induction SBP、 DBP、 HR、 RPP were significantly increased in group A and B, The intubation responses were strongest in group A, and least in group C.SBP、DBP、HR、RPP reached their highest values significantly later and returned to baseline level after intubation. Conclusion 1 mg/kg esmolol both can inhibit the endobronchial intubated cardiovascular response, but mylky more effectively than 0.5 mg/kg esmolol and it can also keep the hemodynamics steady. Key words: Esmolol; General anesthesia; Endobronchial intubation; Cardiovascular response

Effects on electricalrestitution of given esmolol during cardiopulmonary resuscitation in a swine ventricularfibrillation model

：Objective To investigatethe effect on electrical restitution of β1-adrenergic receptor antagonist esmolol administered duringcardiopulmonary resuscitation in the porcine ventricular fibrillation model. MethodVentricular fibrillation untreated for four minutes was induced by dynamic steady statepacing protocol in 40 healthy male pigs, in which local unipolar electrograms wererecorded using one 10-electrode catheter that was sutured to the left ventrieularepicarditan. During CPR, animals were randomized into two groups to receive saline asplacebo or esmolol after two standards doses of epinephrine. At postresuscitation 2-hour,six pigs were randomly selected from each group and the second VF induction was performed.Local activation-recovery intervals (ARI) restitutions and the VF inducibility betweencontrol group and esmolol group were compared. Western blotting was performed to determinecardiac ryanodine receptor (RyR2) protein expression, and their phosphorylation status.Results No sig-nificant differences were observed at the restoration of spontaneouscirculation between two groups. Higher postre-suseitation 2-hour survival rate wasobserved in the esmolol group. Esmolol significantly flattened ARI restitution slope,lessened regional difference of ARI restitution, decreased the VF inducibility, andalleviated RyR2 hyper-phosphorylation. Conclusions Esmolol given during CPR significantlyimproved postresuscitation 2-hour survival rate. Its effects on modulating electricalrestitution property and intracellular calcium handling make up the most important reasonswhy β1-blockadesignificantly reduced the onset and maintenance of VF. Key words: Veutricularfibrillation; Action potentials; Restitution property; Cardiac ryanodinereceptor; Beta-adrenergic receptor

The protection of esmolol to patients with myocardial ischemia received cervical plexus block

Objective To observe the effects of esmolol on patients with myocardial isehemia during cervical plexus block.Methods Forty patients were randomly divided into two groups:the control group(group A),the esmolol group(group B).Each group include 20 cases.Group B received mainline of esmolol 0.4mg/kg(initial dose)and continue infused at a rate of 5mg·kg~(-1)·h~(-1),and group A received normal saline as control.Various irculation function monitoring indexes,change of electrocardiogram and adverse reaction before block,at the end of block and 0min,30min after cervical plexus block were recorded.Results In group A,MAP,HR and RPP were significantly decreased at the end of block and 10min,30min after cervical plexus block compared with before block(P 0.05);comparing the two groups,the corresponding parameter was significantly different at each time after block(P<0.01).In group A,the downward shift distance of S-T section was significantly increased at each time after block than that before block (P<0.05),but in group B,that was significantly decreased(P<0.05);comparing the two groups,the corresponding downward shift distance of S-T section was significantly different at each time after block(P<0.01).The group B have higher proportion of palpitation,headache than that of group A,the difference was significant.Conclusion Esmolol has protective effects in lessening myocardial oxygen consumption,improving myocardial blood oxygen supply and reducing proportion of adverse reaction on patients with myocardial ischcmia. Key words: Esmolol; Myocardial lschemia; Nerve block

Efficacy of flexiblelaryngeal mask airway for airway management in patients undergoing endoscopic sinussurgery

：Objective To evaluate the efficacy of flexible laryngeal maskairway(FLMA)for airway management in patients undergoing endoscopic sinus surgery.MethodsSixty ASA Ⅰ or Ⅱ patients of both sexes,aged 18-60 yr weighing 51-83 kg undergoingendoscopic sinus surgery were randomly divided into 2 groups(n = 30each): tracheal tubegroup(group T)and FLMA group.Anesthesia was induced with midazolam,propofol,remifentaniland vecuronium and maintained with propofol,remifentanil and sevoflurane.Tracheal tube orFLMA was inserted and the patients were mechanically ventilated.BIS was maintained at40-55 and MAP at 60%-70% of the basaeline value during operation.Nitroglycerin(1-3 μg·kg~(-1)·min~(-1))andesmolol(20-30 μg·kg~(-1)·min~(-1))were infused if necessary.BP and HR werecontinuously monitored and recorded before induction of anesthesia,immediately afterinduction at 1,3 and 5 min after insertion of tracheal tube or FLMA and immediately afterremoval of the tracheal tube or FLMA.P_(ET)CO_2,SpO_2,peak and mean airway pressure(P_(peak),P_(mean))were monitored.The use ofnitroglycerin and esmolol infusion,emergence time,the occurrence of coughing andpharyngodynia in 24 h after surgery were also recorded.Results The 2 groups werecomparable with respect to age,body weight,sex ratio and operation time.Systolic BP wassignificantly decreased after insertion of FLMA but increased after tracheal intubation ascompared with the baseline values.P_(peak) was significantly lower in group FLMA than ingroup T.The number of patients who needed nitroglycerin and esmolol infusion duringoperation was significantly smaller,the emergence time shorter and the incidence ofcoughing and panryngodynia after operation lower in group FLMA than in group T.ConclusionThe FLMA is better than tracheal intubation for endoscopic sinus surgery in terms ofhemodynamic changes,emergence from anesthesia and adverse effects. Key words: Laryngeal masks; Otorhinolaryngologic surgical procedures

Development and Validation of a Rapid RP‐HPLC Method for the Estimation of Esmolol Hydrochloride in Bulk and Pharmaceutical Dosage Forms

A reverse phase HPLC method is described for the determination of esmolol hydrochloride in bulk and injections. Chromatography was carried on a C18 column using a mixture of acetonitrile, 0.05 M sodium acetate buffer and glacial acetic acid (35:65:3 v/v/v) as the mobile phase at a flow rate of 1 mL/min with detection at 275 nm. The retention time of the drug was 4.76 min. The detector response was linear in the concentration of 1‐50 μg/mL. The limit of detection and limit of quantification was 0.614 and 1.86 μg/mL respectively. The method was validated by determining its sensitivity, linearity, accuracy and precision. The proposed method is simple, economical, fast, accurate and precise and hence can be applied for routine quality control of esmolol hydrochloride in bulk and injections.

Regional stiffening of the mitral valve anterior leaflet in the beating ovine heart

Left atrial muscle extends into the proximal third of the mitral valve (MV) anterior leaflet and transient tensing of this muscle has been proposed as a mechanism aiding valve closure. If such tensing occurs, regional stiffness in the proximal anterior mitral leaflet will be greater during isovolumic contraction (IVC) than isovolumic relaxation (IVR) and this regional stiffness difference will be selectively abolished by β-receptor blockade. We tested this hypothesis in the beating ovine heart. Radiopaque markers were sewn around the MV annulus and on the anterior MV leaflet in 10 sheep hearts. Four-dimensional marker coordinates were obtained from biplane videofluoroscopy before (CRTL) and after administration of esmolol (ESML). Heterogeneous finite element models of each anterior leaflet were developed using marker coordinates over matched pressures during IVC and IVR for CRTL and ESML. Leaflet displacements were simulated using measured left ventricular and atrial pressures and a response function was computed as the difference between simulated and measured displacements. Circumferential and radial elastic moduli for ANNULAR, BELLY and EDGE leaflet regions were iteratively varied until the response function reached a minimum. The stiffness values at this minimum were interpreted as the in vivo regional material properties of the anterior leaflet. For all regions and all CTRL beats IVC stiffness was 40–58% greater than IVR stiffness. ESML reduced ANNULAR IVC stiffness to ANNULAR IVR stiffness values. These results strongly implicate transient tensing of leaflet atrial muscle during IVC as the basis of the ANNULAR IVC–IVR stiffness difference.

Administration of Esmolol in Microlaryngeal Surgery for Blunting the Hemodynamic Response during Laryngoscopy and Tracheal Intubation in Cigarette Smokers

Cigarette smokers constitute a group of patients with an increased hemodynamic response to tracheal intubation. We studied the dose-response and side effects of bolus administration of esmolol hydrochloride in cigarette smokers undergoing elective microlaryngeal surgery, when esmolol was used for reducing the intense hemodynamic response to laryngoscopy and tracheal intubation. We randomly allocated 165 patients (American Society of Anesthesiologists physical status classes I to III) to receive placebo (Eplac) or esmolol 1 mg/kg (E1) or 2 mg/kg (E2). The esmolol was given 2 minutes before laryngoscopy and tracheal intubation. The same anesthetic technique was used in all patients. Cardiovascular parameters were recorded every minute for the first 5 minutes and thereafter every 3 minutes. Bronchospasm, other side effects, and rescue esmolol treatment were noted during anesthesia. In group Eplac, significant increases (p < .05) in arterial blood pressure and heart rate were observed in the first 3 minutes after tracheal intubation. In group E1, significant increases (p < .05) in diastolic blood pressure were observed in the first 2 minutes after intubation. In group E2, no significant fluctuations were recorded in cardiovascular parameters after intubation. During surgery, 17% of the patients in group Eplac showed an increase in blood pressure and tachycardia. We conclude that esmolol administration of 2 mg/kg during induction of anesthesia in smokers provides hemodynamic stability after laryngoscopy and tracheal intubation with no severe side effects.

The Preventive Stress Response under General Extubation Anesthesia with Esmolol And Tramadol

目的 观察将艾司洛尔和曲马多合用于气管拔管前对拔管期间的心血管反应的影响.方法择期手术病人50例,随机分成A组(艾司洛尔+曲马多,n=25)和B组(对照组),两组皆采用气管插管全麻.比较两组病人拔管期间的心血管反应,同时观察病人的镇静情况.结果A组拔管时,HR、MAP明显低于拔管前水平.B组HR拔管后5、10分钟与拔管前及A组同期比较均增幅显著(P＜0.01),MAP拔管即时及拔管后均有所上升,与拔管前及A组同期比较以拔管时升高显著(P＜0.05).结论艾司洛尔合用曲马多用于气管拔管可预防拔管的应激反应,且病人安静。

The Effect of Intermittent Low Speed Mode Upon Aortic Valve Opening in Calves Supported With a Jarvik 2000 Axial Flow Device

We assessed the effects of an axial flow left ventricular assist device (LVAD) upon aortic valve opening, pump outflow, and biologic and hematologic parameters when operated in intermittent low speed (ILS) mode. An ILS controller equipped Jarvik 2000 LVAD was implanted in six calves. Pump speed was maintained at 10,000 rpm, and pump outflow was measured throughout the study period (71 +/- 6 days [mean +/- SD]). Hematologic and biochemical parameters were analyzed daily for the first 10 days, weekly for the first month, and biweekly thereafter to monitor for kidney or liver dysfunction, hemolysis, bleeding, or infection. Before study termination, esmolol hydrochloride was infused to induce low cardiac output and totally impair aortic valve opening. Radiopaque cineaortography was performed over 30 second intervals (10 seconds before, 10 seconds during, and 10 seconds immediately after ILS controller activation) to assess the effect of ILS mode upon aortic valve opening. After study termination, major end organs and the major vascular tree were removed and examined macroscopically and histologically for thrombus formation and infarction; the aortic valve was examined for thickening and fusion. All pumps were explanted and examined for thrombus formation. All six calves recovered without surgical or mechanical complications. Hematologic and biochemical parameters did not change significantly between baseline and study termination. The aortic valve successfully opened when ILS mode was activated, even under low cardiac output conditions. No thrombus was detected in the major end organs and vascular tree, except for some small renal infarcts in three calves that did not affect renal function. These results indicate that operating an axial flow LVAD in ILS mode allows aortic valve opening and aortic root washout.

Clinical Observation of Effect of Esmolol for Prevention Cardiovascular Reponse to Tracheal Intubation

目的 了解国产盐酸艾司洛尔预防气管插管引起心血管反应的临床效果.方法选择90例ASA Ⅰ-Ⅱ级非心脏手术患者,依据观察药物用量不同,随机分为三组,每组30例,全麻诱导插管前,分别给予艾司洛尔1mg/kg或2mg/kg和0.9%氯化钠注射液10ml,于给药前、给药后及插管后1、2、3、5、10min,监测HR、SBP、DBP变化.结果插管后三组均出现HR增快和SBP、DBP升高改变,SBP、DBP恢复至给药前水平的时间2mg/kg组明显快于1mg/kg组,仅需2min,而对照组需时长达5min,减慢心率2mg/kg组优于1mg/kg组.结论艾司洛尔预防全麻气管插管引起的心血管反应有效,且药效与剂量有关.

The Use of Multi-frequency EPR Techniques to Identify the Radicals Produced in Irradiated β-Blockers

The identification of radicals trapped in irradiated drugs can be very intricate. A multi-frequency electron paramagnetic resonance (EPR) study is proposed to resolve this problem. The Q-band (ca. 34 GHz) comparison with X-band (ca. 9 GHz) did not show significant differences for the four β-blockers studied (atenolol, esmolol, nadolol and propranolol). The use of a higher frequency (285 GHz) was required. It enabled us to determine the g-tensor values of the radicals present in atenolol and esmolol, respectively, g1=2.0086, g2=2.0059 and g3=2.0021 and g1=2.0066, g2=2.0044 and g3=2.0021. The latter was assigned as a phenoxyl radical, which can not be the case for the former. Therefore, radicals produced in esmolol may result from a more complex mechanism than the abstraction followed by the diffusion of an H atom inside the solid. In addition, two molecules as similar as atenolol and esmolol hydrochloride do not contain the same radicals after irradiation. These two conclusions drawn from the EPR results on β-blockers show clearly the importance of continuing the investigations on radiolytic mechanisms in solid-state drugs.

Determination of radical yields in solid-state drugs as one technique to identify drugs that will withstand radiosterilization: radioresistance of beta blockers.

This article describes a simple preliminary test to determine whether a drug is sufficiently radioresistant to withstand radiosterilization. The test is based on the electron spin resonance (ESR) detection of radicals produced after irradiation of a solid-state drug, assuming that these radicals are the precursors of the final products detected after dissolution of the drug. A calibration curve has therefore been established by measuring ESR spectra of l-alanine irradiated at different doses. The response factor to quantify the radicals is the normalized double integration (DI) of the whole first-derivative ESR spectrum. The curve gives the relationship between the normalized DI and the number of radicals. Eight beta blockers have been chosen and their radical yield determined. This is the first time that several different drugs of the same pharmacological group have been studied and compared. The results obtained are similar for seven of the eight beta blockers; the mean G value (excepted for nadolol) is 3 x 10(-9) mol/J. This means that beta blockers are radioresistant. The two most radiosensitive drugs (nadolol and esmolol hydrochloride) were also studied by high-performance liquid chromatography (HPLC). No significant loss of the active compound was detected, which confirms this radioresistant property. Moreover, no change in color or smell was observed. Using ESR and HPLC, beta blockers were identified as potential candidates for radiosterilization.

Anesthesia for electroconvulsive therapy.

Anesthesia for electroconvulsive therapy.

Impact of Myocardial Protection during Coronary Bypass Surgery on Patient Outcome

We have recently shown that continuous coronary perfusion with warm blood enriched with the ultra-short acting ß-blocker Esmolol (ES) improves functional and structural myocardial protection during coronary artery surgery as compared with conventional cardioplegia (CP). The purpose of the present study was to compare both myocardial protection techniques in terms of patient outcome. We retrospectively analyzed the charts of 150 consecutive patients subjected to coronary artery surgery using the ES-technique; 150 patients matched for age, gender, preoperative left ventricular function, history of renal failure, and history of neurological symptoms undergoing surgery with conventional CP during the same time period served as control group. There were no significant differences between both groups with respect to perioperative myocardial infarction rate, need for positive inotropic medication, need for mechanical circulatory support, duration of mechanical ventilation, duration of intensive care unit stay, time of mobilization, postoperative renal failure, cardiac arrhythmias, neurological symptoms, infections or in-hospital mortality. ES-patients were less frequently readmitted to the intensive care unit (ES: 3/150; 2.2% [95% confidence interval: 0–4.2%] vs CP: 13/150; 8.7% [4.2–13.2%]; P= 0.010) and total hospital stay was shorter (ES: 12.3±14.8 days [95% CI: 11.5–13.0] vs CP: 13.5±3.8 [12.9–14.1] days; P= 0.0013), thus saving 159 patient days on the normal ward. Procedural costs were less for the ES-technique (US$ 60 per patient) as compared to the cardioplegia technique (US$ 120 per patient). These data suggest that myocardial protection using the ES-technique does not improve clinical outcome in patients subjected to routine coronary artery surgery, but may save costs.

Cardiovascular indices of peripheral and central sympathetic activation.

A number of sympathetic nervous system (SNS) parameters have been used in cardiovascular psychophysiology. This study aimed to describe the pattern and redundancy of a set of SNS parameters during peripherally induced changes of cardiac sympathetic activation and reflex modulation of central SNS control. Preejection period (PEP) was assessed as a marker of peripheral sympathetic activation. Low-frequency blood pressure variability (BPV) was assessed as an estimate of central SNS control. Peripheral beta-sympathetic stimulation and blockade were achieved with epinephrine and esmolol hydrochloride (beta1-blockade), respectively. Changes in central SNS output were induced by loading and unloading arterial baroreceptors with norepinephrine and nitroprusside sodium, respectively. This single-blinded, crossover study in 24 healthy men also included two placebo control periods. PEP was derived from impedance cardiography and adjusted individually for heart rate. BPV was calculated by power spectral analyses of beat-to-beat heart rate and systolic blood pressure (Finapres system) data. PEP decreased during epinephrine infusion (-40.1 +/- 3.8 ms, p <.0001) and increased during esmolol infusion (+6.6 +/- 3.5 ms, p =.05). PEP was shortened after central SNS activation by nitroprusside (-16.8 +/- 2.9 ms, p < 0.0001). Systolic BPV in the low-frequency range (0.07-0.14 Hz, Mayer waves) increased during nitroprusside infusion (+0.44 +/- 0.19 ln mm Hg(2), p =.03) and decreased during norepinephrine infusion (-0.67 +/- 0.13 ln mm Hg(2), p < 0.0001). Low-frequency BPV did not change significantly during epinephrine or esmolol infusion. Our data provide empirical evidence of separable peripheral and central sympathetic response components. The combined report of low-frequency BPV and PEP gives distinct information on both central SNS control and the level of sympathetic cardiac activation achieved.

Impact of myocardial protection during coronary bypass surgery on patient outcome

We have recently shown that continuous coronary perfusion with warm blood enriched with the ultra-short acting ß-blocker Esmolol (ES) improves functional and structural myocardial protection during coronary artery surgery as compared with conventional cardioplegia (CP). The purpose of the present study was to compare both myocardial protection techniques in terms of patient outcome. We retrospectively analyzed the charts of 150 consecutive patients subjected to coronary artery surgery using the ES-technique; 150 patients matched for age, gender, preoperative left ventricular function, history of renal failure, and history of neurological symptoms undergoing surgery with conventional CP during the same time period served as control group. There were no significant differences between both groups with respect to perioperative myocardial infarction rate, need for positive inotropic medication, need for mechanical circulatory support, duration of mechanical ventilation, duration of intensive care unit stay, time of mobilization, postoperative renal failure, cardiac arrhythmias, neurological symptoms, infections or in-hospital mortality. ES-patients were less frequently readmitted to the intensive care unit (ES: 3/150; 2.2% [95% confidence interval: 0–4.2%] vs CP: 13/150; 8.7% [4.2–13.2%]; P=0.010) and total hospital stay was shorter (ES: 12.3±4.8 days [95% CI: 11.5–13.0] vs CP: 13.5±3.8 [12.9–14.1] days; P=0.0013), thus saving 159 patient days on the normal ward. Procedural costs were less for the ES-technique (US$ 60 per patient) as compared to the cardioplegia technique (US$ 120 per patient). These data suggest that myocardial protection using the ES-technique does not improve clinical outcome in patients subjected to routine coronary artery surgery, but may save costs.

Comparison of hemodynamic responses to dexmedetomidine versus esmolol in patients undergoing beating heart surgery

Background: Alpha 2-adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. Also, administration of beta -adrenergic antagonists contributes to prophylaxis against hypertension, tachycardia and myocardial ischemia and myocardial protection during cardiac surgery. The effects of dexmedetomidine (DEX), a highly specific alpha -adrenergic agonist, on these responses have not yet been fully reported in patients undergoing cardiac surgery. Esmolol (ESM) is a cardioselective, short-acting - blocking agent. Previous studies have established the effectiveness of esmolol in the reduction of hemodynamic responses during anesthetic induction. Aim: The study of hemodynamic responses of dexmedetomidine and esmolol and their effects on the anesthetic requirements during anesthesia in beating heart surgery. Conclusion: Dexmedetomidine in patients undergoing beating heart surgery decreased intraoperative sympathetic tone, induced sedation, attenuated hyperdynamic responses to anesthesia and surgery and overall hemodynamic variability than esmolol. The need for anesthetics, muscle rigidity, perioperative myocardial ischemia and shivering were less also in DEX group.