Assessment of Spinal Cord Ischemia With Near-Infrared Spectroscopy: Myth or Reality?

Non-invasive near-infrared spectroscopy is gaining popularity in the detection of spinal cord ischemia following aortic aneurysm repair. However, practical recommendations are lacking. This review focuses on the physiological and anatomical background, as well as on the clinical implementations of near-infrared spectroscopy as a tool for monitoring ischemia of the spinal cord. Clinical recommendations based on the currently available evidence are rendered.

Relation between mixed venous oxygen saturation and cerebral oxygen saturation measured by absolute and relative near-infrared spectroscopy during off-pump coronary artery bypass grafting.

BACKGROUND: We hypothesized that previously reported contradictory results regarding the equivalence of mixed venous (Smv(O(2))) and cerebral (rS(c)O(2)) oxygen saturation might be related to time delay issues and to measurement technology. In order to explore these two factors, we designed a prospective clinical study comparing with relative (INVOS(®)) and absolute (Foresight(®)) rS(c)O(2) measurements. METHODS: Forty-two consenting patients undergoing elective off-pump coronary artery bypass grafting were included. Two INVOS and two Foresight sensors continuously registered rS(c)O(2). Smv(O(2)) was measured continuously via a pulmonary artery catheter. Data were assessed by within- and between-group comparisons and correlation analysis. RESULTS: A similar time delay of 19 (4) and 18 (4) s was found for compared with rS(c)O(2) measurements by Foresight and INVOS, respectively, during haemodynamic changes. After adjusting for this time delay, the correlation between Smv(O(2)) and rS(c)O(2) increased from r=0.25 to 0.75 (P<0.001) for Foresight, and from r=0.28 to 0.73 (P<0.001) for INVOS. Comparison of Foresight and INVOS revealed significant differences in absolute rS(c)O(2) values (range 58-89% for Foresight and 28-95% for INVOS). Changes in rS(c)O(2) in response to acute haemodynamic alterations were significantly more pronounced with INVOS compared with Foresight (P<0.001). CONCLUSIONS: Considering the important time delay with Smv(O(2)), rS(c)O(2) seems to reflect more appropriately acute haemodynamic alterations. This might suggest its use as a valid alternative to invasive monitoring of tissue oxygen saturation. Relative and absolute rS(c)O(2) measurements demonstrated significant differences in measured rS(c)O(2) values and in the magnitude of rS(c)O(2) changes during haemodynamic alterations.

Influence of variations in systemic blood flow and pressure on cerebral and systemic oxygen saturation in cardiopulmonary bypass patients.

BACKGROUND: Although both pressure and flow are considered important determinants of regional organ perfusion, the relative importance of each is less established. The aim of the present study was to evaluate the impact of variations in flow, pressure, or both on cerebral and whole-body oxygen saturation. METHODS: Thirty-four consenting patients undergoing elective cardiac surgery on cardiopulmonary bypass were included. Using a randomized cross-over design, four different haemodynamic states were simulated: (i) 20% flow decrease, (ii) 20% flow decrease with phenylephrine to restore baseline pressure, (iii) 20% pressure decrease with sodium nitroprusside (SNP) under baseline flow, and (iv) increased flow with baseline pressure. The effect of these changes was evaluated on cerebral (Sc(O2)) and systemic (Sv(O2)) oxygen saturation, and on systemic oxygen extraction ratio (OER). Data were assessed by within- and between-group comparisons. RESULTS: Decrease in flow was associated with a decrease in [from 63.5 (7.4) to 62.0 (8.5) %, P<0.001]. When arterial pressure was restored with phenylephrine during low flow, Sc(O2) further decreased from 61.0 (9.7) to 59.2 (10.2) %, P<0.001. Increase in flow was associated with an increase in Sc(O2) from 62.6 (7.7) to 63.6 (8.9) %, P=0.03, while decreases in pressure with the use of SNP did not affect Sc(O2). Sv(O2) was significantly lower (P<0.001) and OER was significantly higher (P<0.001) in the low flow arms. CONCLUSIONS: In the present elective cardiac surgery population, Sc(O2) and Sv(O2) were significantly lower with lower flow, regardless of systemic arterial pressure. Moreover, phenylephrine administration was associated with a reduced cerebral and systemic oxygen saturation.

Occupational exposure to sevoflurane during cardiopulmonary bypass.

Volatile anaesthetic agents are widely used for maintenance of anaesthesia in all kinds of surgical procedures. Despite the implementation of measures such as adequate ventilation of the operating room and the use of efficient scavenging systems, concern remains about the risks for occupational exposure, especially in situations associated with an increased risk of anaesthetic gas waste, such as with the use of volatile anaesthetic agents on cardiopulmonary bypass. The present contribution reports the results of a preliminary safety assessment involving measurements of sevoflurane concentrations in the ambient air of a cardiac surgery operating room. In 22 cardiac surgical procedures with cardiopulmonary bypass (11 with open and 11 with closed venous reservoir), measurements of trace concentrations were obtained every 10 min at the following sites: at the outlet of the oxygenator, at the outlet of the cardiotomy reservoir, in the breathing zone of the perfusionist and above the surgical field. The concentrations were measured on-line using a photoacoustic infrared spectrometer. Mean sevoflurane waste concentrations remained consistently below the recommended target value of 4.68 ppm throughout the observation period at the different measurement sites. These results indicate that, with the use of sevoflurane on cardiopulmonary bypass, the recommended levels for occupational exposure are not exceeded, provided adequate operation room ventilation and waste gas scavenging is performed.

Effects of moderate acute isovolaemic haemodilution on myocardial function in patients undergoing coronary surgery under volatile inhalational anaesthesia.

When myocardial oxygen demand is increased by elevated heart rate in patients undergoing coronary artery surgery under total intravenous anaesthesia, acute isovolaemic haemodilution may be associated with a deterioration of cardiac function. We investigated the effects of acute isovolaemic haemodilution during volatile inhalational anaesthesia. Forty patients undergoing coronary surgery were randomly assigned to two groups according to the rate of atrioventricular pacing (Group 70 at 70.min(-1) and Group 90 at 90.min(-1)). While paced at the fixed heart rate, acute isovolaemic haemodilution was performed before the start of cardiopulmonary bypass. In both groups mean (SD) stroke volume increased with haemodilution (from 65 (9) to 83 (10) ml.min(-1) (p < 0.01) in Group 70 and from 65 (9) to 81 (9) ml.min(-1) (p < 0.01) in Group 90) as a result of a decrease in systemic vascular resistance (from 1175 (231) to 869 (164) dynes.s.cm(-5) (p < 0.01) and from 1060 (185) to 849 (146) dynes.s.cm(-5) (p < 0.01), respectively) and an increase in end-diastolic volume (from 1049 (234) to 1405 (211) ml (p < 0.01) and from 1078 (106) to 1438 (246) ml (p < 0.01), respectively). Left ventricular pressure-derived data remained unchanged with acute isovolaemic haemodilution in both groups.

Does the use of a volatile anesthetic regimen attenuate the incidence of cardiac events after vascular surgery?

OBJECTIVE: To compare the effects of a volatile anesthetic to a non-volatile anesthetic regimen on the incidence of postoperative cardiac events, including the postoperative elevation of troponin I values after arterial vascular surgery in high risk patients. DESIGN: Retrospective analysis of data of a phase II study that compared the Na+/H+ exchanger type II inhibitor, zoniporide to placebo on the occurrence of cardiac events. SETTING: Multicenter study conducted in 105 sites throughout the United States, South America, Europe and Asia. PARTICIPANTS: 784 subjects scheduled for urgent or elective major arterial vascular surgery and a history of at least 3 of the following: age > or = 65 years, hypertension, documented stroke or transient ischemic attack, previous myocardial infarction, active angina pectoris diabetes mellitus, congestive heart failure, or symptomatic cardiac arrhythmia. INTERVENTIONS: Type of anesthesia was retrospectively retrieved from the database and patients were subdivided in two groups: inhalational (group A) vs non-inhalational anesthetic regimen (group B). Incidence of postoperative cardiac events was compared between the two groups. MEASUREMENTS AND MAIN RESULTS: The incidence of postoperative cardiac events was not different between the two groups. Maximum postoperative troponin I levels was not different between the two groups in the total population and in the patients undergoing peripheral arterial surgery. In patients undergoing aortic surgery the incidence of elevated troponin levels higher than 1.5 and 4 ng x mL(-1) tended to be lower in group A than in group B in the aortic surgery (28% vs 18% and 30% vs 20% respectively) but this difference did not reach statistical significance. CONCLUSION: The results of this hypothesis-generating study suggest that potential beneficial effects on extent of postoperative myocardial damage in high risk patients undergoing arterial surgery will probably be more apparent in abdominal aortic surgery than in peripheral vascular surgery. Further sufficiently powered studies using a standardized protocol should now be performed to definitively address this question.

Cardiac surgery with cardiopulmonary bypass: does aprotinin affect outcome?

BACKGROUND: Aprotinin, a non-specific serine protease inhibitor, has been used for two decades to reduce perioperative blood loss and the risk for allogeneic transfusion in cardiac surgery. This study evaluated the effects of aprotinin on outcome (mortality, cardiac events, renal failure, and cerebrovascular events) in such patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: Data were obtained in patients who received a strict blood conservation protocol: no antifibrinolytic therapy when at low risk (n = 854) and aprotinin (n = 1210) when at high risk for blood transfusion. Relative risk of different pre- and intra-operative variables was calculated for the different outcome variables. Backward stepwise logistic regression analysis was used to identify the independent risk factors associated with the different outcome variables. Statistical significance was accepted at P < 0.01. RESULTS: Postoperative mortality and morbidity were higher in the aprotinin group but this was related to an increased incidence of perioperative risk factors. Mortality was similar to that predicted by the Euroscore. Complex surgery was the only independent variable associated with postoperative cardiac events. Preoperative heart failure, preoperative creatinine > 1.5 mg dl(-1), urgent, and redo surgery were the independent variables associated with postoperative haemodialysis. Age > 70 yr was identified as the only independent variable associated with neurologic dysfunction. CONCLUSIONS: In the present study, patients receiving aprotinin as part of a strict blood conservation strategy represent a population at high risk for postoperative complications. For the outcome variables studied, aprotinin administration was not identified as an independent risk factor.

Incidence of atrial fibrillation early after cardiac surgery: can choice of the anesthetic regimen influence the incidence?

Occurrence of atrial fibrillation is a common complication after coronary surgery. This study aimed to identify the perioperative factors that are associated with its occurrence with specific attention to the possible influence of the choice of the anesthetic regimen after elective coronary surgery. A retrospective chart analysis was performed in 460 patients who underwent elective coronary artery surgery with cardiopulmonary bypass using the standard institutional anesthetic, surgical and postoperative protocols. The only difference in management was the choice of the primary anesthetic regimen. 110 patients had a total intravenous anesthesia with propofol, 90 patients had a total intravenous anesthesia with midazolam, 150 patients were anesthetized with sevoflurane and 110 patients with desflurane. The primary outcome variable was the incidence of atrial fibrillation within the first 24 postoperative hours. Atrial fibrillation occurred in 64 of the 460 patients included (13.9%). Multiple logistic regression analysis identified increased age (> 70 years), EuroSCORE > 4, prolonged CPB time (> 100 min) and need for prolonged inotropic support (> 6 hours) as the significant independent risk factors for the occurrence of postoperative atrial fibrillation. The incidence of postoperative atrial fibrillation differed among the different anesthetic groups with the lowest incidence in the sevoflurane group (propofol: 17/110; midazolam: 15/90; sevoflurane: 9/150; desflurane: 23/110) (p = 0.004). This finding should be further confirmed in a prospective sufficiently powered multicenter study.

Sodium nitroprusside enhances in vivo left ventricular function in beta-adrenergically stimulated rabbit hearts.

OBJECTIVE: Sodium nitroprusside (SNP) is an activator of soluble guanylate cyclase, which depresses myocardial contractility. These exclusively negative inotropic effects of SNP were recently challenged by in vitro data.. In isolated rat ventricular myocytes, a moderate increase of cGMP improved the contractile response at baseline and in isoprenaline-stimulated conditions. The present study evaluated in vivo the inotropic effects of SNP at baseline and during administration of low dose dobutamine. METHODS: Anesthetized open-chest rabbits (n = 18) were instrumented with micromanometers, ultrasound crystals and atrial pacing wires. Measurements were obtained during caval occlusion with ventilation suspended at end-expiration. Systolic function was assessed with dP/dtmax and the slope Ees of the end-systolic pressure-volume relation. Diastolic function was assessed with the time constant tau and the stiffness constant Kc of the diastolic pressure-volume relation. SNP (0.02, 0.08, 0.32 microgram x kg-1) was administered at baseline and during low dose dobutamine. RESULTS: At baseline, SNP reduced dP/dtmax from 3750 +/- 88 to 3470+/- 88 mmHg/s (mean +/- s.e.m.) and Ees from 148 +/- 16 to 103 +/- 13 mmHg/ml (P < 0.01) . During dobutamine infusion, SNP increased dP/dtmax from 4340 +/- 125 to 4681 +/- 230 mmHg/s and Ees from 148 +/- 19 to 190 +/- 30 mmHg/ml (P < 0.01). Effects of SNP on dP/dtmax and Ees were different at baseline and during dobutamine (interaction P < 0.01). SNP did not alter Kc at baseline nor during dobutamine. CONCLUSIONS: SNP enhances in vivo systolic function in beta-adrenergically stimulated rabbits.

The influence of labetalol on arterial blood gas data, pulmonary haemodynamics and pulmonary shunting.

The arterial oxygen and carbon dioxide tensions, pulmonary and systemic haemodynamics and pulmonary shunting and mechanics were measured during the first 30 min after intravenous labetalol administration. Thirty patients, recovering in the intensive care unit after neurosurgical interventions were randomly divided in 2 groups of 15 patients, receiving either labetalol or placebo. In the labetalol treated group the arterial oxygen tension decreased from 553.6 +/- 16.8 to 529.3 +/- 19.8 mmHg 5 min after the injection of labetalol. A concomitant increase in arterial carbon dioxide tension from 40.1 +/- 1.1 to 45.5 +/- 1.3 mmHg was noticed. Pulmonary vascular resistance decreased from 159.6 +/- 14.7 to 116.7 +/- 11.7 dynes.sec.cm-5 and pulmonary shunting increased from 4.8% +/- 1.4% to 8.1% +/- 2.4% 5 min following injection. All these changes were statistically significant for p less than 0.01. After 30 min all values had returned to their initial level. No changes were registered in the control group. As airway resistance appeared not to be affected by the labetalol administration it may be concluded that the observed changes in blood gas data are most likely due to a transient decrease of the pulmonary vascular resistance with a concomitant increase in pulmonary shunting.

The hemodynamic manifestation of normal myocardial relaxation. A framework for experimental and clinical evaluation.

Myocardial relaxation clinically manifests itself as left ventricular pressure (LVP) fall. The transition from contraction to relaxation is the precise moment at which 81-84% of peak isometric force has developed or the equivalent timing early during ejection. Defining the completion of relaxation and distinguishing relaxation from diastole appears merely semantic. Diastole is not a passive phase of the cardiac cycle. During diastole mechanical left ventricular properties still change due to incomplete relaxation, due to creep and stress relaxation, and due to autoregulation by preload and by nitric oxide. Description of timing and rate of LVP fall may provide useful information on underlying cardiac diseases such as ischaemia and hypertrophy. This information will however only be reliable if systolic cardiac function and systolic load are normal, and in the absence of a significant degree of nonuniformity, such as induced by conduction disturbances or by regional myocardial ischemia. The various effects of load and of nonuniformity on myocardial relaxation in the normal heart are reviewed. Coupling of timing and rate of LVP fall are explained in terms of cross-bridge mechanics. Specific effects of systolic pressure on LVP fall and their relation to systolic cardiac function are emphasized. These data constitute a conceptual framework for the analysis of myocardial relaxation in cardiovascular research and in the cardiac patient. Comparison of clinical and experimental data during manipulation of afterload should lead to an improved understanding of clinical relaxation disturbances and to a therapeutic approach, which is relevant from the physiopathological point of view. LVP fall may provide useful and quantitative information on systolic LV function if measurements are performed under different conditions of systolic load. This information is similar to systolic pressure-volume relations, but can be performed with the sole use of a micromanometer in the LV cavity.

Inotropic effects of sodium nitroprusside: a clinical study on coronary surgery patients.

OBJECTIVE: Sodium nitroprusside (SNP) induces release of nitric oxide and is widely used as a vasoactive drug. Recent research analyzed effects of SNP on cardiac muscle and described variable inotropic effects. The present study evaluated effects of SNP on left ventricular (LV) function in patients undergoing coronary artery surgery. METHODS: The study was performed in 100 patients with a preoperative ejection fraction > 40%. LV pressures were measured with a fluid-filled catheter in the LV cavity. Hearts were placed in AV sequential mode at a rate of 90 beats/min. Measurements were obtained at end-expiration and consisted of a control tracing and a tracing obtained after a 5 min infusion of SNP 0.5 microgram.kg-1.min-1. These measurements were obtained before and after cardiopulmonary bypass (CPB). An average of 5 consecutive beats was obtained for analysis. Ventricular function was assessed with LV pressure and dP/dt. Data were analyzed using two factor analysis of variance for repeated measurements. RESULTS: 1. Baseline patient data (n = 80). Before CPB, a variable inotropic response to SNP was observed. The direction of the inotropic response was related to preoperative beta-blocking medication. LVP and dP/dtmax increased with SNP in patients without preoperative beta-blocking medication. In patients on preoperative beta-blocking medication, SNP did not alter LVP and dP/dtmax. After CPB, a positive inotropic response was not observed in any of the patients. 2. Postoperative patient data under dobutamine (n = 20). Data of these separate observations were similar to baseline data before CPB. After CPB and under dobutamine administration (5 micrograms.kg-1.min-1) all 20 patients developed a positive inotropic response to SNP. CONCLUSIONS: In coronary surgery patients, SNP induced variable inotropic effect. The direction of the inotropic response appeared to be modulated by the beta-adrenergic drive.

Study on the effects of six intravenous anesthetic agents on regional ventricular function in dogs (thiopental, etomidate, propofol, fentanyl, sufentanil, alfentanil).

This study evaluates the effects of 30 min increasing doses infusions of six intravenous anesthetic agents (thiopental, etomidate, propofol, fentanyl, sufentanil and alfentanil) on regional ventricular function in a normal and an acute ischemic heart segment in dogs. Part 1 discusses the methodology used in this experimental design with emphasis on the sensitivity and the limitations of the parameters used to assess ventricular performance and contractility. Part 2 reports the effects on regional and global ventricular function, which occur when one segment is made acutely ischemic. Part 3 reports and discusses the effects of increasing infusions of the three induction agents thiopental, etomidate and propofol on systemic and regional ventricular function. These agents induced a dose-dependent decrease in left ventricular end-systolic pressure. End-diastolic length also decreased in the normal and the acute ischemic segment for the three agents, indicating a decrease in left ventricular loading. This effect was most pronounced for propofol. At the doses tested, etomidate did not alter regional myocardial function significantly in any of the two segments. Thiopental, on the other hand was associated with a dose-dependent decrease in systolic shortening, that was significantly greater in the ischemic segment. This suggested that thiopental depresses myocardial function more in the acute ischemic heart than in the normal heart. Propofol decreased systolic shortening similarly in both segments. In part 4 the effects of the three narcotics fentanyl, sufentanil and alfentanil are reported. Fentanyl and sufentanil induced a dose-dependent decrease in heart rate. Left ventricular end-systolic pressure remained unchanged despite the increasing infusion rate. Fentanyl increased regional end-diastolic length and systolic shortening at the highest infusion rate. This phenomenon is not apparent for sufentanil, suggesting that different mechanisms are involved to compensate for the expected bradycardia-induced hypotension. Alfentanil did not alter systemic and regional hemodynamics significantly in this study design.

Prediction and early diagnosis of acute myocardial ischemia during anesthesia: a critical review.

Adequate myocardial oxygenation is the result of a good balance between the myocardial oxygen supply and the oxygen demand. Recognition of an insufficient myocardial oxygenation is particularly difficult during general anesthesia because angina pectoris, one of the most reliable indicators of ischemia cannot be expressed. Therefore other indices must be used. Considerable interest but also controversy surrounds the question which routinely monitored determinant of myocardial oxygen supply and demand best predicts and diagnoses beginning myocardial ischemia. A thorough understanding of the sensitivity and the limitations of the different monitoring techniques is a must for every anesthetist dealing with patients with coronary artery disease. The present state of knowledge and the new trends appearing on this subject are reviewed.

The negative inotropic effect of sevoflurane is not mediated through nitric oxide synthase in rat papillary muscle.

Sevoflurane has dose-dependent negative inotropic effects on myocardial contractility. The current study investigated whether the nitric oxide pathway is involved in these effects. A laboratory, ex-vivo experiment was performed on 66 isolated papillary muscles. Effects of increasing concentrations of sevoflurane (1, 2 and 3 MAC) were assessed in control conditions, in the presence of Nw-nitro-L-arginine (L-NOARG) and in beta-adrenergic stimulated rat papillary muscles. Contractility was assessed by total developed tension. In baseline conditions, the administration of increasing concentrations of sevoflurane caused a dose-dependent reduction in contractility of respectively 8.6 +/- 1.7%, 14.4 +/- 4.8% and 23.6 +/- 3.9%. This negative inotropic effect was not significantly altered by the administration of the NO-synthase inhibitor L-NOARG (p = 0.09). Under continuous administration of 3 MAC sevoflurane, 4 consecutive concentrations of isoproterenol induced a mean increase of contractility of respectively 43.0 +/- 13.7%, 65.9 +/- 22.6%, 131.2 +/- 25.6% and 122.3 +/- 31.2%. After administration of L-NOARG, the 4 consecutive concentrations of isoproterenol induced a mean increase in contractility of respectively 36.0 +/- 8.5%, 75.0 +/- 17.8%, 143.0 +/- 42.8% and 120.0 +/- 51.4% (p = 0.85). These data indicated that the negative inotropic effects of sevoflurane in rat papillary muscles, both in basic as in beta-adrenergic stimulated conditions, were not altered by blocking the NO-cGMP-system.

Role of the nitric oxide-cGMP pathway in the cardiovascular effects of anesthetic agents: a review.

Over the past 10 years, there has been an explosion of new information on the physiological and pathophysiological roles of nitric oxide (NO) within the cardiovascular system. With the increasing knowledge on the importance of NO in the regulation of cardiovascular function, possible involvement of the NO-cyclic guanosine-monmphosphate (cGMP) pathway in myocardial effects of anesthetics has attracted wide attention. This paper reviews the literature on the role of the nitric oxide-cGMP pathway in cardiovascular effects of volatile and intravenous anesthetics.

Perioperative myocardial ischaemia and infarction in connection with cardiac and non-cardiac surgery.

Although perioperative myocardial infarction has a relative low incidence, its occurrence is associated with a high morbidity and mortality. Although many single risk factors for developing a perioperative myocardial infarction have been described, it soon became apparent that surgical risk could hardly be determined by one single factor. A multifactorial approach for the preoperative assessment of patients at risk for developing cardiac complications in association with surgery and anesthesia was introduced. Further investigation, however, indicated that the risk of developing a perioperative myocardial infarction was not only determined by preoperative risk factors and a number of peroperative risk factors were also identified. Since identification of those patients, particularly at risk for developing a perioperative myocardial infarction, is a matter of prime importance in the choice of the treatment and the monitoring, a thorough understanding and knowledge of the different pre- and peroperative risk factors is a must for every surgeon and anesthetist.

Coronary artery bypass grafting on the beating heart using the Octopus method.

STUDY OBJECTIVE: To study the usefulness and effectiveness of off-pump coronary bypass grafting with the Octopus heart stabilizing device. METHOD: The files of thirty-one patients undergoing coronary artery bypass with the aid of the Octopus heart stabilizing device between April 1996 and October 1998 were studied retrospectively. Patients were divided into group A (n = 23), patients with single or double vessel disease and technically suitable coronary lesions for off-pump procedure and group B (n = 8), patients with multiple vessel disease considered to be with excessive risk for cardiopulmonary bypass due to poor general condition combined with renal failure and/or chronic obstructive pulmonary disease. Standard median sternotomy (n = 27), lateral thoracotomy (n = 1) or minithoracotomy (n = 3) were performed for access and for harvesting the left internal mammary artery (LIMA). MEASUREMENTS AND RESULTS: The mean number of bypasses was 1.2 and 1.1 in groups A and B, respectively. Thirty patients received a LIMA graft to the left anterior descending artery (LAD). Homologous blood transfusions were needed in five patients (21%) in group A and four (50%) in group B. There were no wound infections or neurologic complications. All patients in group A survived and are asymptomatic. One patient in group B died of septic shock, two have residual angina pectoris or dyspnea, and five are asymptomatic. CONCLUSION: Coronary artery bypass using the Octopus heart stabilizing device proved to be a safe and effective technique resulting in complete revascularization in group A patients with no mortality. Incomplete revascularization may offer a substantial benefit to patients who cannot tolerate cardiopulmonary bypass due to poor general condition. We prefer median sternotomy, allowing precise harvesting of the internal mammary artery and more precise anastomoses without increased morbidity.

Randomised clinical trial: the synbiotic food supplement Probiotical vs. placebo for acute gastroenteritis in children.

BACKGROUND: Some probiotic strains reduce the duration of acute diarrhoea. As a result of strain and product specificity, each product needs support by clinical data. AIM: In children with acute diarrhoea, to test the efficacy of the synbiotic food supplement Probiotical (Streptoccoccus thermophilus, Lactobacillus rhamnosus, Lactobacillus acidophilus, Bifidobacterium lactis, Bifidobacterium infantis, fructo-oligosaccharides). The primary end-points were duration of diarrhoea and the number of children that had a normalised stool consistency. METHOD: A total of 111 children with acute diarrhoea (median age 40 months) were included in this randomised, prospective placebo-controlled parallel clinical trial in primary health care. All children were treated with oral rehydration solution ad libitum and with the synbiotic (n=57) or placebo (n = 54). RESULTS: The median duration of diarrhoea was 3 days (IQ 25-75: 2-4 days) in the Probiotical group, compared with 4 days (IQ 25-75: 4-5 days) in the placebo group (P<0.005). The number of children with normal stool consistency (defined as stool Bristol score ≤4) was higher in the synbiotic group on days 2 and 3 [21 vs. 2% (P<0.001) and 50 vs. 24% (P<0.001) respectively]. Less additional medication (antipyretics, antiemetics, antibiotics) was administered in the synbiotic group. Physicians were globally more satisfied with the synbiotic food supplement treatment than with placebo (P=0.005). One patient in the placebo group was hospitalised. CONCLUSION: The median duration of diarrhoea was significantly 1 day shorter in the synbiotic than in the placebo group, associated with decreased prescription of additional medications.