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Aim. To assess the effect on left ventricular (LV) function of atrioventricular (AV) and ventricular pacing at the LV apical or lateral wall and to compare the normal torsional and deformation pattern of the intact LV myocardium with those created by the aforementioned LV pacing modes and sites. Methods. Experiments were conducted in pigs (n = 21) with normal LV function to investigate the acute hemodynamic effects of epicardial AV and ventricular LV pacing at the LV apical or lateral wall. Torsional and deformation indices of LV function were assessed using speckle tracking echocardiography. Results. AV pacing at the apex revealed a significant reduction in the radial strain of the base (P < 0.03), without affecting significantly the ejection fraction and the LV torsion or twist. In contrast, AV pacing at the lateral wall produced, in addition to the reduction of the radial strain of the base (P < 0.01), significant reduction of the circumferential and the radial strain of the apex (both P < 0.01) as well as of the ejection fraction (P < 0.002) and twist (P < 0.05). Conclusions. In pig hearts with intact myocardium, LV function is maintained at sinus rhythm level when AV pacing is performed at the LV apex.

Introduction: The aim of this study was to determine whether left ventricular (LV) apical rotation assessed by speckle tracking echocardiography (STE) can predict global LV systolic dysfunction after acute anterior myocardial infarction (AMI)., Methods: STE analysis was applied to LV short-axis images at the basal and apical levels in 21 open-chest pigs, before and after left anterior descending coronary artery ligation. LV radial and circumferential strain and strain rate, apical and basal rotation, and LV torsion were recorded., Results: LV apical rotation (3.68 ± 1.73° pre-AMI vs. 2.19 ± 1.64° post-AMI, p<0.009), peak systolic rotation rate, and radial and circumferential strain as well as strain rate decreased significantly 30 min postAMI. The LV global torsion decreased significantly. Strain and rotational changes of the LV apex were primarily correlated with ejection fraction (EF), but those of the LV base were not. EF had a significant correlation with the global LV twist (r=0.31, p<0.05). On multivariate linear regression analysis, fractional shortening of the long-axis (FSL) (b=0.58, p<0.001), rotation of the LV apex (b=0.32, p<0.006) and LV dp/dtmax (b=0.26, p<0.02) were independently related with EF. On analysis, of the receiver operating characteristic curve, the area under the curve for apical rotation was 0.765, p<0.006; the best cutoff value of 2.92° had sensitivity 80% and specificity 71% in predicting EF<40%., Conclusion: Apical rotation assessed by STE is a potential noninvasive early indicator of global LV systolic dysfunction in AMI and has a satisfactory association with LVEF. Its assessment could be valuable in clinical and research cardiology.

Background: The purpose of the present study was to examine the effect of SonoVue™ on right ventricular (RV) dimensions and contractility in patients with heart failure., Patients and Methods: Twenty-four patients were divided into two groups. Group A consisted of 15 patients with heart failure and group B (control) of nine patients without heart disease. SonoVue was administered at low (2 ml) and high (4 ml) doses in both groups separately, in a random order. RV dimensions, contractility, peak systolic pressure gradient from tricuspid regurgitation (TRPG) and the time to maximal RV end-diastolic dimension (EDD), as well as the time for RV-EDD to return to the baseline value (recovery), were calculated in every cardiac cycle starting before the administration of SonoVue (baseline) until the recovery of RV-EDD., Results: Low-(group A, p<0.001 and group B, p<0.05) and high-dose (group A, p<0.0001 and group B, p<0.01) contrast infusion increased the RV-EDD compared to baseline values. TRPG increased significantly (p<0.05) in both groups, under low-as well as high-dose. In group A, high-dose compared to low-dose produced a significant delay in the time duration to max RV-EDD (p<0.05) and in the time to RV-EDD recovery (p<0.0001)., Conclusion: The administration of SonoVue in patients with heart failure was followed by an acute, transient, dose-dependent increase in RV-EDD and TRPG, without any effect on RV contractility.

The diagnosis of intestinal obstruction in pregnancy is difficult, as the symptoms may mimic pregnancy-associated complaints. The surgical management is challenging, as the mortality rate of midgut volvulus in pregnancy is high. We report the case of a 35-year-old woman at 21 weeks and 5 days of gestation with small bowel obstruction who presented to our institution with a 24 h history of colicky abdominal pain and nausea and who finally had a successful open repair.

Acute myocardial infarction (AMI) causes left ventricular (LV) remodeling, which forms the substrate for its early and late complications. The purpose of this study was to compare the acute effect of dobutamine or intra-aortic balloon pumping (IABP), alone or in combination, on LV function in the early phase of an experimental AMI. In 18 pigs, AMI was induced by ligation of the left anterior descending artery (LAD). IABP or dobutamine infusion at a rate of 5 µg/kg/min, or a combination of the two, was applied immediately after ligation of the LAD. Echocardiographic measurements of the long and short LV axes were obtained before (baseline) and post LAD ligation and at the end of each intervention for 5, 15, and 30 min. The fractional shortening (FS) of both axes, as well as the ejection fraction (EF), was calculated. The combination of dobutamine with IABP increased the EF significantly after the AMI in comparison to dobutamine or IABP alone, and improved the stroke volume, cardiac output, and long axis FS in comparison to IABP alone. Dobutamine alone produced a significantly higher increase of EF in comparison to IABP alone. These results indicate that the combination of dobutamine with IABP may be useful during AMI., (© 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Objective: The early appearance of ventricular fibrillation (VF) following acute myocardial infarction (MI) is associated with adrenergic effects and electrical interactions although some early "mechanical" changes may also occur. The aim of the present experimental study was to examine whether early changes in the functional geometry of left ventricular (LV) contraction may be associated with ventricular arrhythmias occurring during the first 120min of MI., Methods: In 11 swine left anterior descending (LAD) coronary artery ligation was performed. Aortic flow, LV end-diastolic pressure (LVEDP), LV long and short axis lengths were measured and their fractional shortening (FS) was calculated before and during the initial 120min period of MI., Results: LV long axis FS and aortic flow decreased (p<0.001) whereas LVEDP increased (p<0.01) in all 11 animals within 30min following LAD ligation. LV long and short axis lengths and LV short axis FS did not change significantly. VF occurred in 5 of the 11 animals within this 30min period. LV short axis FS decreased (p<0.05) in all 5 animals prior to VF and increased (p<0.05) in all 6 animals without VF. In 3 of the 6 animals that had no VF during the initial 30min VF occurred later. Similarly, LV short axis FS decreased prior to VF in all those 3 animals. LV short axis FS did not decrease in any of the remaining 3 swine without VF during the same period of time., Conclusion: Early changes in the functional geometry of LV contraction, in the form of a reduction of LV short axis FS, are associated with a greater incidence of VF in experimental acute MI., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

The aim of this double-blind, randomized control trial was to compare the effectiveness of intra-articular ropivacaine alone or with morphine or ketoprofen for controlling pain after arthroscopic knee surgery. One hundred fifty-six patients scheduled for elective knee arthroscopy were recruited. All patients received general anesthesia and were randomly assigned to 4 groups to receive intra-articular ropivacaine 40 mg (group R), ropivacaine 24 mg plus morphine 8 mg (group R+M), ropivacaine 36 mg plus ketoprofen 100 mg (group R+K), or normal saline (group N/S). Pain, sedation, orientation, nausea, vomiting, and urine retention were recorded at 0, 1, 2, 4, 8, 12, and 24 hours postoperatively. Pain was evaluated by a 10-cm visual analog scale (VAS). When the pain was >2, a suppository of 400 mg paracetamol plus 10 mg codeine plus 50 mg caffeine was given. Results showed that at 4 hours postoperatively, pain differed significantly among the 4 groups (P<.001), with less pain recorded in the R+M group. Similarly, the number of suppositories administered postoperatively to the R+M group was significantly less (P<.001) vs the other groups. Patients who received ropivacaine and morphine or normal saline had a higher incidence of nausea and vomiting vs the other groups (P=.001 and P=.036, respectively). The combination of intra-articular ropivacaine and morphine is associated with less pain after knee arthroscopy during early recovery but with a higher incidence of nausea and vomiting. However, the addition of ketoprofen to ropivacaine provides relatively satisfactory pain relief, but with fewer side effects compared to morphine., (Copyright 2011, SLACK Incorporated.)

Background: The aim of this study was to examine the effects on left ventricular (LV) function of LV apical or/and lateral wall pacing during an experimental acute myocardial infarction., Methods: In 12 anesthetized pigs, epicardial LV pacing at the apex or lateral wall, or at both sites simultaneously, was performed before and after left anterior descending (LAD) ligation. Data concerning LV function were obtained by two-dimensional echo during spontaneous sinus rhythm (SR) and during pacing before and 15, 45, 60, and 90 minutes after LAD ligation., Results: Before ligation of the LAD, pacing at the lateral wall (48.04 ± 6.25%) or both sites (45.71 ± 6.31%) reduced the LV ejection fraction (EF) significantly (P < 0.01) in comparison to SR (55.44 ± 4.10%). However, during pacing at the apex (50.19 ± 6.50%), the reduction was not significant. After LAD ligation, the EF during lateral pacing (43.02 ± 7.71%) was significantly higher than during apical pacing (38.78 ± 8.26%, P < 0.04) but was not significantly different from that during dual-site pacing (41.65 ± 8.69%)., Conclusions: Pacing within the ischemic LV apical zone after LAD ligation impairs left ventricular ejection fraction, as compared with pacing the nonischemic LV lateral wall, and should therefore be avoided in clinical settings where the LV pacing site may be chosen., (©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.)

We investigated parturients' preference for neuraxial vs general anaesthesia, while they have experienced both techniques in the past. A total of 102 parturients who underwent elective caesarean section under general or neuraxial anaesthesia at different times completed a questionnaire comparing the two techniques. According to our results, 98% vs 51% (p < 0.001) of the women saw the baby and 51% vs 29% (p = 0.003) ambulated in the neuraxial and general anaesthesia groups, respectively, within the first 24 h postoperatively. Neuraxial anaesthesia was associated with less pain assessed by the Verbal Analogue Scale (VAS) (54 ± 21 vs 72 ± 20 p < 0.001), fewer days of hospital stay (4 ± 0.5 vs 5 ± 1.5, p = 0.001) and higher satisfaction scores (77 ± 18 vs 52 ± 24, p = 0.001) vs general anaesthesia. Finally, 80% of the women would choose neuraxial anaesthesia for a future caesarean section.

Background: The aim of this study was to investigate the effect of coronary flow (CF) changes and inflammatory indices on myocardial microcirculation--assessed by myocardial contrast echocardiography (MCE)--and on left ventricular remodelling, in an experimental ischaemia-reperfusion model., Methods: In 15 pigs, weighing 30 +/- 5 kg, ligation of the left anterior descending (LAD) coronary artery was performed, followed by reperfusion for 120 min. Peak, mean, duration and volume of systolic and diastolic components of CF distal to the LAD ligation were measured using a butterfly flowmeter and their ratio was calculated. The following two-dimensional echocardiography indices of LV geometry/function were measured from the apical four-chamber view: LV end-systolic (ESD) and end-diastolic (EDD) dimension long- (Ls, Ld) and short-axis (Ss, Sd) and their ratio (Ld/Sd, Ls/Ss, defined as the sphericity index). Interleukin (IL) 1beta, 6, 10 and tumour necrosis factor (TNF) were measured in samples obtained from the LV cavity and coronary sinus. A 0.5 ml/min injection slow bolus over 30 s of SonoVue was made into the left ventricle (LV) in order to assess myocardial perfusion by MCE. Standard apical four-chamber views were digitally acquired and stored for off-line analysis using the Echofit system. The peak intensity (Ac) of the microbubbles at the apex, distally to ligation, was normalised with respect to the peak intensity of the microbubbles in the LV cavity. All parameters were recorded at baseline, immediately after ligation and at 5, 15, 30, 60, 120 min during reperfusion. The percentage changes of CF indices, echocardiographic parameters, interleukins and Ac between baseline and reperfusion were calculated., Results: Mean systolic CF, systolic volume, peak and mean diastolic flow (MDF) changes and epicardial mean CF, Ld/Sd, Ls/Ss changes and coronary sinus IL-6 (IL-6 cs) were inversely correlated with Ac changes during reperfusion. At 5 and 15 min of reperfusion (hyperaemic phase), the greatest median increase of mean diastolic (172% and 86%), and mean systolic CF (713% and 344%) and the greatest reduction of Ac (-41% at 5 min) compared to baseline (P < 0.05) were observed. The maximum increase of IL-6 cs (40%) was detected at 120 min. ROC analysis showed that of all examined echocardiography indices an increase of mean diastolic CF > 22% was the best predictor of a >25% reduction of Ac with 76% sensitivity and 65% specificity (area 71%, CI 54%-85%, P = 0.02). In addition an >32% increase of IL-6 at 120 min of reperfusion predicted a >25% reduction of Ac with a 76% sensitivity and 65% specificity (area 71% CI 61%-97%, P = 0.01)., Conclusion: Changes of mean diastolic CF and IL-6 cs are associated with alterations in myocardial microvascular integrity after ischaemia-reperfusion and may be used as a predictor of myocardial dysfunction.

Background: : The aim of the present study was to examine the effect of the second-generation ultrasound contrast agent (2nd GUCA) SonoVue on right ventricular (RV) dimensions and contractility and to investigate whether a dose-related interaction exists between the contrast agent and RV function., Methods: : Twenty-eight pigs were randomly assigned to 3 groups for intravenous administration: a low-dose group (0.5 cc of SonoVue), a high-dose group (1 cc of SonoVue), and a control group (2 cc of normal saline). RV end-diastolic (EDD) and end-systolic dimension (ESD) and pulmonary pressure (PP) were measured, and the fractional shortening (FS%) was calculated before the administration of SonoVue or normal saline and after the return of the RV-EDD or PP to the baseline value. The time to reach maximal RV-EDD or PP value and the time until the return of RV-EDD or PP to the baseline value were also measured., Results: : Contrast agent infusion was followed by an acute transient increase of RV-EDD, RV-ESD, FS, and PP in both the low-dose and high-dose groups, but the increase was greater in the high-dose group. FS and PP did not change significantly in the control group. A dose-dependent delay in the time from baseline to maximum RV-EDD and PP was detected in the high-dose group (P < 0.001 for both) as well as a delay in the return from maximum to the baseline values (P < 0.001 for both)., Conclusions: : Administration of the 2nd GUCA SonoVue is associated with an acute, transient, dose-dependent RV dilatation and an increase in pulmonary pressure with a consequent impact on RV contractility.

Introduction: The contribution of the collateral network to myocardial oxygenation under normal circumstances is not clear. However, it is possible that in diseased myocardium this network may be activated and contributes significantly to cardiac blood supply. The purpose of this study was to examine the coronary sinus flow after acute, synchronous, complete occlusion of all epicardial coronary arteries and to investigate methods to increase the flow in the setting of ischaemia., Methods: In 8 pigs, the coronary sinus flow was measured after complete ligation of all coronary arteries. In two of the 8 experiments adrenaline and dobutamine were infused into the left ventricular cavity, while clamping of the ascending aorta was performed in another three animals in an effort to increase left ventricular systolic pressure., Results: The mean coronary sinus flow decreased from 36.06 +/- 11.01 ml/min to 5.61 +/- 6.96 ml/min (p < 0.001) after ligation of the coronary arteries. A 67% mean reduction of coronary sinus flow at the first minute after ligation was observed and a progressive decrease of coronary sinus outflow to almost zero within 60 minutes was seen in some experiments. Neither infusion of adrenaline and dobutamine nor ascending aorta clamping increased the coronary sinus flow., Conclusions: The preservation of coronary sinus flow after the complete occlusion of all coronary arteries indicates that retrograde flow through the collateral network from cardiac chambers may exist. Methods that increase the blood flow through the collateral network may contribute to the improvement of myocardial perfusion in severe coronary insufficiency.

Introduction: Acute myocardial infarction causes left ventricular (LV) remodelling, which forms the substrate for its early and late complications. The aim of this experimental study was to evaluate the acute changes in LV functional geometry after acute myocardial infarction using echocardiography and to investigate the effect of continuous intravenous dobutamine administration on those changes., Methods: In 22 pigs acute myocardial infarction was induced by ligation of the anterior descending branch of the left coronary artery. In 11 animals dobutamine was administered at a rate of 5 microg/kg/min (Group B), while the remainder (Group A) served as controls. Before infarction and 5, 15, 45 and 75 minutes after, the fractional shortening of the long (FSL) and short (FSS) axes of the LV were measured echocardiographically and the ejection fraction (EF) was calculated., Results: In Group A FSL and EF reduced significantly after infarction (p < 0.0001), while FSS increased significantly (p < 0.05). In Group B FSL and EF reduced significantly 5 minutes after infarction and then returned progressively to normal values after 15 min (EF) and 45 min (FSL). FSS did not change significantly during 75 minutes after infarction., Conclusions: Dobutamine, administered at a rate of 5 microg/kg/min during acute experimental anterior myocardial infarction, before the appearance of early complications, may prevent the acute, unfavourable remodelling of the LV, as manifested by a decrease in FSL and EF and a compensatory increase in FSS.

Background: Several methods may enhance the inhalational induction of anesthesia. In this randomized double-blind study, we evaluated the speed of induction of anesthesia with sevoflurane with or without pre-oxygenation., Methods: Fifty-four patients scheduled for hysteroscopy received for 10 min air or 100% oxygen via a facemask followed by > or = 7% sevoflurane in 100% oxygen. During the first 300 s of sevoflurane administration, bispectral index (BIS) values were recorded every 30 s in all patients. In 14 patients, seven in each group, BIS, endtidal CO(2), tidal volume, respiratory rate, SpO(2), and heart rate were recorded every minute during the pre-induction period and every 30 s during the first 5 min of sevoflurane administration., Results: The BIS, endtidal CO(2), tidal volume and respiratory rate did not differ between the oxygen or air breathing groups (P = 0.696, P = 0.999, P = 0.388, and P = 0.875, respectively), though the oxygen group exhibited lower tidal volumes by 16-20%. The SpO(2) and heart rates were higher in the oxygen breathing group (P < 0.001 and P = 0.042, respectively). During sevoflurane administration, BIS values were lower in the oxygen group vs. the group breathing air, in particular at 90, 120, 150, 180 and 210 s (P = 0.001, P = 0.001, P = 0.001, P = 0.001 and P = 0.030, respectively). The endtidal CO(2) and the tidal volumes between the groups did not differ. The two groups differed in the SpO(2) and the heart rates during induction (P = 0.004 and 0.003, respectively)., Conclusions: Before sevoflurane administration, breathing 100% oxygen for 10 min enhances induction of anesthesia with sevoflurane.

Study Objective: To compare recovery and restoration of cognitive function after fentanyl-propofol or remifentanil-propofol anesthesia administration in patients undergoing carotid endarterectomy., Design: Randomized, double-blind, prospective study., Setting: Department of Anesthesiology, University hospital., Patients: Seventy patients with ASA physical statuses II and III (53 men and 17 women) undergoing elective carotid endarterectomy., Interventions: Anesthetic technique and drugs were identical in the 2 groups, with the exception of remifentanil and fentanyl administration. Induction of anesthesia was obtained with a bolus dose of propofol (1-2 mg/kg), maintenance was achieved with a propofol infusion according to hemodynamics and nitrous oxide/oxygen (FIO(2), 0.50). Muscle relaxation was achieved with rocuronium. The remifentanil group received 1 microg/kg of remifentanil as a single dose during the induction of anesthesia and 0.5 microg/kg per minute as an infusion throughout the procedure. The fentanyl group received 2 microg/kg of fentanyl as a single dose during the induction of anesthesia., Measurements: Intraoperative hemodynamic adverse events were recorded. All patients were also evaluated with regard to their recovery and the restoration of their cognitive function, recording the immediate recovery times and using the Aldrete score 15 and 60 minutes after surgery and the Hasegawa scale 6 hours after surgery. For evaluation of postoperative pain, the Numeric Pain Scale (0-10) was used., Main Results: Patients receiving remifentanil had significantly (P < .05) fewer episodes of intraoperative hypertension and needed nitroglycerine administration less frequently (P < .05) than those receiving fentanyl. Immediate recovery was significantly earlier (P < .05) with remifentanil (eye opening, 5.1 +/- 1.3 [remifentanil] and 7.2 +/- 3.7 [fentanyl] minutes; extubation time, 5.4 +/- 1.9 [remifentanil] and 7.8 +/- 4.1 [fentanyl] minutes). The Hasegawa Dementia Scale scores 6 hours after surgery and Aldrete scores 15 and 60 minutes after surgery did not differ significantly between the 2 groups. Pain levels were also similar for patients taking remifentanil and fentanyl., Conclusions: Although intraoperative hemodynamics were better preserved and immediate recovery was more rapid with remifentanil, overall postoperative recovery and restoration of cognitive functions as well as postoperative pain intensity seem to be similar for patients receiving remifentanil and for those receiving fentanyl combined with propofol for carotid endarterectomy operations.

Ondansetron, a selective 5-HT3 antagonist has been proved to be an effective antiemetic agent for prophylaxis of nausea and vomiting after surgery. This study was conducted to determine whether ondansetron changes thiopental requirements for induction of anesthesia in patients unpremedicated and premedicated with diazepam. One hundred sixty eight adult female patients classified as American Society of Anesthesiologists (ASA) physical status I (normal healthy patient) or II (patient with mild systemic disease) participated in this prospective, double blinded, randomized study. Patients were assigned to receive either 0.07 mg/Kg diazepam orally or no premedication. They then received saline and ondansetron 0.1 mg/Kg or 0.2 mg/Kg intravenously 5 minutes before thiopental induction. Thiopental was administered at a rate of 25 mg/min until the patient lost the ability to open eyes on command. Thiopental requirements were not significantly different among groups. The results indicate that ondansetron in clinically used doses does not influence the hypnotic requirements of thiopental.

Flumazenil (Anexate), a new benzodiazepine antagonist, was administered in doses of 0.2-0.4 mg to 40 patients for reversing the sedative effects of midazolam used as the sole induction agent in doses of 0.15-0.25 mg x kg-1 for short operations with a mean duration of 35 +/- 10 min. Five min after flumazenil was given, 33 patients (82.5%) were fully conscious, while 38 patients (95%) were able to converse 30 min after administration. Flumazenil was very well tolerated in almost all cases, the only side effects being mild confusion in 3 patients and nausea in 3 other cases.