Effects of levosimendan on myocardial ischaemia-reperfusion injury.

BACKGROUND AND OBJECTIVE: Levosimendan has a cardioprotective action by inducing coronary vasodilatation and preconditioning by opening KATP channels. The aim of this study was to determine whether levosimendan enhances myocardial damage during hypothermic ischaemia and reperfusion in isolated rat hearts. METHODS: Twenty-one male Wistar rats were divided into three groups. After surgical preparation, coronary circulation was started by retrograde aortic perfusion using Krebs-Henseleit buffer solution and lasted 15 min. After perfusion Group 1 (control; n = 7) received no further treatment. In Group 2 (non-treated; n = 7), hearts were arrested with cold cardioplegic solution after perfusion and subjected to 60 min of hypothermic global ischaemia followed by 30 min reperfusion. In Group 3 (levosimendan treated; n = 7), levosimendan was added to the buffer solution during perfusion and the hearts were arrested with cold cardioplegic solution and subjected to 60 min of hypothermic global ischaemia followed by 30 min reperfusion. At the end of the reperfusion period, the hearts were prepared for biochemical assays and for histological analysis. RESULTS: Tissue malondialdehyde levels were significantly lower in the levosimendan-treated group than in the non-treated group (P = 0.019). The tissue Na+-K+ ATPase activity was significantly decreased in the non-treated group than in the levosimendan-treated group (P = 0.027). Tissue myeloperoxidase (MPO) enzyme activity was significantly higher in the non-treated group than in the levosimendan-treated group (P = 0.004). Electron microscopic examination of the hearts showed cardiomyocytic degeneration at the myofibril, mitochondria and sarcoplasmic reticulum in both non-treated and levosimendan-treated groups. The severity of these findings was more extensive in the non-treated group. CONCLUSIONS: Treatment with levosimendan provided better cardioprotection with cold cardioplegic arrest followed by global hypothermic ischaemia in isolated rat hearts.

Could adding magnesium as adjuvant to ropivacaine in caudal anaesthesia improve postoperative pain control?

Recently, most studies reported magnesium as a N-methyl-D-aspartate receptor antagonist and its analgesic and perioperative anaesthetic effects have been discussed with central desensitization pathway. We investigated the effects of caudal ropivacaine plus magnesium and compared with ropivacaine alone on postoperative analgesia requirements. After hospital ethic committee's consent, 60 patients (ASA I-II, 2-10 years old) who had lower abdominal or penoscrotal surgery were enrolled in the study. After general anaesthesia induction, caudal blockage was applied. Patients were randomly assigned in two groups. Ropivacaine 0.25% was administered to Group R (n=37), ropivacaine 0.25% plus 50 mg magnesium to Group RM (n=23) in 0.5 ml kg-1 volume. Postoperative analgesia level was recorded at 15 min and 1, 2, 3, 4, 6 h by using Paediatric Objective Pain Scale (POPS) and The Children's Hospital of Eastern Ontoria Pain Scale (CHEOPS). Postoperative motor blocks were evaluated with Modified Bromage Motor Block Scale. According to demographic characteristics, there were no significant differences between the two groups (P>0.05). POPS, CHEOPS, Bromage Motor Scales, analgesia duration and adverse effects were similar in Group R and Group RM. It has been shown that addition of magnesium as an adjuvant agent to local anaesthetics for caudal analgesia has no effect on postoperative pain and analgesic need.

Utility of color duplex sonography in the assessment of efficacy of the stellate ganglion blockade.

PURPOSE: To assess the hemodynamic changes in the upper extremity arteries after sympathetic ganglion blockade (SGB) by using spectral Doppler parameters and to determine the applicability of these parameters for the evaluation of SGB efficacy. MATERIAL AND METHODS: Spectral Doppler parameters (peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (mean V), flow volume, resistive and pulsatility indices (RI, PI), inner arterial diameters (intima to intima) (D) with simultaneous recordings of heart rate (HR), systolic and diastolic blood pressures and upper extremity surface temperature changes) were recorded before and 5 min after during the first, fifth and tenth SGB procedures. RESULTS: SGB induced an increase in skin temperature in the ipsilateral hand and persistent dilatation of the radial diameter accompanied by reduction of RI and PI in the radial and third digital arteries in all patients. CONCLUSION: Hemodynamic changes assessed by spectral Doppler parameters could be used as sensitive and objective measurements of peripheral sympathetic nervous activity and vascular tonus, and may confirm a successfully performed SGB.