Biomedical subjects

M Georgieff

Publications and source records attributed to M Georgieff.

At least 55 records · Page 3Linked to original sources

PubMed2000

[The effect of hepatosplanchnic circulation in treatment of trauma and sepsis. Beyond O2-supply O2-uptake relationship?].

Sepsis and SIRS are characterised by increased hepatosplanchnic blood flow and oxygen transport due to sepsis-associated hypermetabolism with enhanced oxygen uptake. Regional hypermetabolism may be linked with a mismatch of oxygen availability and demand potentially resulting in a pathological splanchnic oxygen uptake/supply dependency. Splanchnic hypermetabolism has been hypothesised to be due to increased hepatic gluconeogenesis caused by accelerated glucose precursor uptake resulting from increased release from the peripheral tissues. This increased precursor efflux is triggered by cytokines. The response of splanchnic haemodynamics and oxygen kinetics, however, to therapeutic interventions does not necessarily parallel the different metabolic pathways. Therefore, understanding of both tissue perfusion and oxygenation as well as metabolism is pivotal for evaluating the effects of different therapeutic strategies in intensive care medicine.

Humans↗

PubMed2000

Hepatic O2 exchange and liver energy metabolism in hyperdynamic porcine endotoxemia: effects of iloprost.

OBJECTIVE: To compare the effects of a 12 h continuous infusion of iloprost, a stable prostacyclin analogue, on hepatic blood flow (Qliv), O2 exchange, and energy metabolism during a 24 h hyperdynamic, porcine endotoxemia with volume resuscitation alone. DESIGN: Prospective, randomized, experimental study with repeated measures. SETTING: Investigational animal laboratory. SUBJECTS: Twenty-eight domestic pigs: 16 animals during endotoxemia with volume resuscitation alone (ETX), 12 with endotoxemia, volume resuscitation, and treatment with iloprost (ILO). INTERVENTIONS: Endotoxemia was initiated by continuous infusion of E. coli lipopolysaccharide. Animals were resuscitated with hetastarch, aimed at maintaining a MAP of > 60 mmHg. After 12 h of endotoxemia, iloprost was administered for 12 h in the treatment group, titrated to avoid pharmacologically induced hypotension (MAP < 60 mmHg). MEASUREMENTS AND RESULTS: Iloprost significantly increased Qliv, with no effect on hepatic O2 delivery. Mean capillary hemoglobin O2 saturation (HbScO2) on the liver surface, as well as HbScO2 frequency distributions--a measure of microcirculatory O2 availability--remained unchanged. Treatment with iloprost, however, significantly attenuated the endotoxin-induced derangements of cellular energy metabolism as reflected by the diminished progressive decrease in hepatic lactate uptake rate and a blunted increase in hepatic venous lactate/pyruvate ratios. While endotoxin significantly increased endogenous glucose production (EGP) rate, iloprost restored EGP to normal at the end of the experiment. CONCLUSIONS: Thus, in a clinically relevant model of human sepsis, iloprost did not produce potential adverse effects but rather ameliorated hepatic metabolic disturbances and, thereby, hepatic energy balance.

Animals↗

PubMed2000

Evaluation of three risk scores to predict postoperative nausea and vomiting.

BACKGROUND: So far there are three different scores to predict postoperative vomiting (PV: Apfel et al., 1998) or postoperative nausea and vomiting (PONV: Koivuranta et al., 1997; Palazzo and Evans, 1993). All three scores used logistic regression analysis to identify and create weights for the risk factors for PV or PONV. In short, these were sex, age, history of previous PONV, motion sickness, duration of anaesthesia, and use of postoperative opioids. However, an external evaluation and a comparison of these scores has not been performed so far. METHODS: Patients undergoing a variety of surgical procedures under general anaesthesia were studied prospectively. Preoperatively, they completed a questionnaire concerning potential risk factors for the occurrence of PV or PONV implemented in the three risk scores. Balanced anaesthesia (induction agent, nondepolarising neuromuscular blocker, opioid, and inhalation agent in nitrous oxide/oxygen) was performed. No intravenous anaesthesia or any antiemetic prophylaxis was applied. Postoperatively, the patients were observed in the recovery room for the occurrence of PV and PONV and were visited twice on the ward within the 24-h observation period. Both the patients and the nursing staff were asked whether PV or PONV was present. The severity of PONV was categorised using a standardised scoring algorithm. A total of 1,444 patients was finally included into the analysis. Using information of the predicted risk for the individual patients and the actual occurrence of PV or PONV, Receiver Operator Characteristics (ROC-curves) were drawn. The area under each ROC-curve was calculated as a means of the predictive properties of each score and was compared for statistical differences. RESULTS: For prediction of PONV (any severity) the AUC-values (AUC=area under the curve) and the corresponding 95%-confidence intervals were: Apfel: 0.70 (0.67-0.72); Koivuranta: 0.71 (0.69-0.73); Palazzo: 0.68 (0.65-0.70). For prediction of PV: Apfel: 0.73 (0.71-0.75); Koivuranta: 0.73 (0.70-0.75); Palazzo: 0.68 (0.65-0.70). Thus, all three scores appeared to have a moderate accuracy as measured by the AUC. The score of Koivuranta predicts PONV (P=0.007) and also PV (P=0.002) significantly better than Palazzo's score. Furthermore, for predicting of PV the score of Apfel was also superior to Palazzo's score (P=0.005). All three scores predict PV with the same accuracy as PONV. CONCLUSION: The occurrence of PV and PONV in patients undergoing surgery under balanced anaesthesia can be predicted with moderate but acceptable accuracy using one of the available risk scores, regardless of local surgical or anaesthesiological circumstances. For clinical practice, we recommend the score published by Koivuranta, since its calculation is very simple.

Adult↗

PubMed2000

Droperidol and 5-HT3-receptor antagonists, alone or in combination, for prophylaxis of postoperative nausea and vomiting. A meta-analysis of randomised controlled trials.

BACKGROUND: Droperidol and 5-HT3-receptor antagonists are among the most potent antiemetics to prevent postoperative nausea and vomiting (PONV). Combinations of these drugs have been used to increase the efficacy of antiemetic treatment. However, so far the quantitative effect of this combination has not been evaluated systematically. METHODS: Results from randomised controlled trials investigating the efficacy of 5-HT3-receptor antagonists or droperidol alone versus the combination of both drugs to prevent PONV were included in a meta-analysis. Studies were systematically searched using Medline, EMBASE, the Cochrane-Library, and by manually screening the reference lists of matching review articles and current issues of locally available peer-reviewed anaesthesia journals. Seven papers with data on granisetron published by Fujii and co-workers were not considered. The main end point in each study was defined as occurrence of nausea, retching, or vomiting within 6 h ("early PONV") and within 48 h ("late PONV") after surgery. The relative risks (RR) and the numbers needed to treat (NNT) of the pooled data with their corresponding 95% confidence intervals (given in parentheses) were calculated using a random effects model. RESULTS: Eight studies with 881 patients (adults: n=801; children (mean age: 8 yr): n=80) were included in the analysis. Droperidol was applied to 340 patients, 5-HT3-receptor antagonists to 198, and 343 were treated with a combination of both drugs. Seven out of these eight studies reported increased antiemetic efficacy of the combination group compared with the single drugs (droperidol and 5-HT3-receptor antagonists respectively). However, in none of the trials did this difference reach statistical significance. When a meta-analytic analysis based on these results was performed the combination of droperidol with a 5-HT3-receptor antagonist was not associated with a significantly increased antiemetic efficacy. In 12 to 13 patients a 5-HT3-receptor antagonist has to be added to droperidol prophylaxis to prevent one additional patient from PONV who would have had suffered from PONV when treated with droperidol alone (RR "early PONV": 1.52 (0.95-2.44); RR "late PONV": 1.24 (0.89-1.74)). Similar results were obtained when the antiemetic effect of adding droperidol to a prophylaxis with 5-HT3-receptor antagonists was analysed. In this case 10 to 12 patients have to be treated with the 5-HT3-droperidol combination instead of with a 5-HT3-receptor antagonist alone to prevent one additional patient from PONV (RR "early PONV": 1.55 (0.68-3.52); RR "late PONV": 1.29 (0.77-2.17)). There were no reports of an increased incidence of adverse effects. CONCLUSION: The data on the combination of droperidol with 5-HT3-receptor antagonists suggest that there is a trend towards increased efficacy of the combination therapy compared to the single drugs. However, so far there are insufficient data to recommend this combination treatment for prophylaxis.

Antiemetics↗

PubMed2000

[Target controlled infusion (TCI)--status and clinical perspectives].

The technique of target controlled infusion (TCI) has influenced the development of intravenous anaesthesia substantially and opens the possibility of many new and exciting applications in peri-operative anaesthetic care. The launch of "Diprifusor" as the first commercially available TCI system for propofol was the cornerstone of a successful research period within the last decade, which evaluated the pharmacokinetic foundations of computer assisted intravenous drug delivery. We are now in a period where TCI technology is becoming a part of routine anaesthesia technique for the practitioner rather than a research tool for specialists and enthusiasts. This review gives an update on the rational pharmacokinetic basis of TCI development, the preliminary clinical experience with the new technique, the performance and accuracy of TCI devices and potential technical pitfalls in clinical routine. Besides clinical application in anaesthesia with "Diprifusor" TCI, target controlled systems are expected to play a significant role as research tools in the evaluation of drug interactions in anaesthesia and in the development of novel control techniques for the administration of sedative and analgesic drugs in the peri-operative period.

Anesthesia, Intravenous↗

PubMed2000

[Clonidine compared to midazolam for intravenous premedication for ambulatory procedures. A controlled double blind study in ASA 1 patients].

OBJECTIVE: Midazolam is frequently used for premedication in day-case surgical patients whereas clonidine is rarely administered for this indication. However, clonidine has several useful effects that make the drug an interesting alternative to conventional premedicants. Thus, in this randomised, double-blind, and controlled study the anxiolytic effect of midazolam was compared to that of clonidine. Furthermore, effects on postoperative complaints and minor complications, and readiness for discharge were investigated. METHODS: 100 ASA-1 patients undergoing wisdom teeth extraction on a day-case basis were included into the analysis. A further 50 patients who received no premedication served as a control group. General anaesthesia was standardised (propofol-fentanyl-isoflurane in N2O/O2). The anxiolytic effect of the premedication was assessed using the Erlanger anxiety- and tension scale (EAS). The test was applied before and after intravenous premedication with 1.5 micrograms/kg clonidine or 50 micrograms/kg midazolam and repeated once postoperatively. During recovery the incidence and severity of pain, nausea and vomiting, and shivering were recorded. The readiness for discharge was assessed using standardised discharge criteria. The recording of data was completed by a telephone interview on the day after surgery. RESULTS: The demographic data of the groups did not differ. In the two treatment groups there was a time-dependent decrease of anxiety and tension. However, postoperatively there was no difference between the levels of anxiety and inner tension between the premedicated patients and the untreated control group. Furthermore there was no difference in the incidence and severity of any postoperative complications. Time until the patients were ready for discharge did not differ between the three groups. CONCLUSION: The effects of an intravenous premedication with 1.5 micrograms/kg clonidine or 50 micrograms/kg midazolam, respectively in young ASA-1 patients undergoing minor surgical procedures on a day-case basis are restricted to decrease of anxiety and inner tension before surgery. No beneficial effects were found during the postoperative period compared with untreated control patients.

Adjuvants, Anesthesia↗

PubMed2000

[Impact of environmental factors on the incidence of posteropative nausea and vomiting. Influence of the weather and cycle of the moon].

OBJECTIVE: In a survey concerning postoperative nausea and vomiting an unexpected high number of the participants stressed the impact of environmental factors, like weather and--even more surprising--the phase of the moon, on the occurrence of postoperative nausea and vomiting (PONV). Thus, the aim of this study was to determine the influence of these factors on the incidence of PONV. METHODS: On 203 days within the 19-month study period, 2488 patients were followed up for at least 24 hours postoperatively to determine the occurrence of PONV. For each day the actual incidence of PONV was compared with the mean predicted risk of PONV calculated with two risk scores for prediction of PONV (Koivuranta, 1997; Apfel, 1998). 32 days with the most significant difference between actual and predicted incidence of PONV were analysed retrospectively by two biometeorological experts, who were blind to the information whether each day was associated with a high or low incidence of PONV, evaluated the possible impact of the weather of these days. To analyse the influence of the cycle of the moon it was prospectively classified into four different phases. RESULTS: The two biometeorologists rated 22 out of the presented 32 days correctly. The likelihood p that this rating happened by chance is 0.0251, assuming that the likelihood for predicting each day correctly is 0.5 (independent Bernoulli-experiments, e.g. throwing a coin). However, days with a high or low incidence of PONV were equally distributed within the four phases of the moon (p = 0.97; chi 2-test with Yates' correction). CONCLUSION: Results from this analysis suggest that the weather may have some impact on the occurrence of PONV. However, our data do not support the hypothesis that the phases of the moon have any influence on this symptom.

Adult↗

PubMed2000

Building a large-scale perioperative anaesthesia outcome-tracking database: methodology, implementation, and experiences from one provider within the German quality project.

The German Society of Anaesthesiology and Intensive Care Medicine evaluates voluntary, standardized, everyday, perioperative anaesthesia outcome measures. A standard minimal data set is collected for national benchmarking. This article reviews the implementation of a data acquisition system in one academic centre that has participated in this long-term nationwide project since its initiation in 1992. The population studied comprised 96,107 patients up to 1997. The overall incidence of anaesthesia-related incidents, events and complications (IEC) was 22%. Results are presented and discussed for 63 different IEC, seven functional system categories and five severity grades. The proposed methodology, using computer-readable records, was suitable for comprehensive and detailed outcome documentation. However, an extensive data validation system was necessary. IEC reporting results were largely dependent on the documentation culture. The future of outcome tracking in routine anaesthesia may lie in multicentre comparisons with multivariate-adjusted risk and comorbidity data from each provider's integrated information system.

Algorithms↗

PubMed2000

Xenon does not induce contracture in human malignant hyperthermia muscle.

Xenon has many characteristics of an ideal anaesthetic agent. It is not known whether xenon is a safe alternative to the potent inhalational anaesthetics in patients susceptible to malignant hyperthermia (MH). We investigated the effect of xenon, halothane and caffeine on muscle specimens of 31 individuals, referred to the MH Unit of the University of Ulm, and performed genetic epidemiology. Thirteen individuals were classified as MH susceptible and 18 as MH negative. Xenon 70% did not cause an increase in baseline tension of any MH-susceptible muscle specimen in contrast to halothane and caffeine. The evoked twitch response increased transiently in MH-susceptible and normal specimens indicating a mechanism independent of MH susceptibility. These results suggest that xenon, in concentrations up to 70% may be a safe anaesthetic for MH-susceptible patients.

Anesthetics, Inhalation↗

PubMed2000

A multicenter study of 4-chloro-m-cresol for diagnosing malignant hyperthermia susceptibility.

UNLABELLED: Standardization of the in vitro contracture test (IVCT) for malignant hyperthermia (MH) susceptibility has resulted in very rare false negative tests. However, false positive results stigmatizing the patient seem to be more frequent than false negative results and make supplementary tests desirable. This multicenter approach studied the usefulness of an IVCT with 4-chloro-m-cresol (4-CmC), a ryanodine receptor-specific agonist for a better definition of MH susceptibility. Diagnosis made by the standard IVCT was compared with the results of this 4-CmC test on muscle specimens of 202 individuals from 6 European MH centers. In the 4-CmC test, the results of the MH susceptible group differed significantly from both the MH normal and the MH equivocal group. 4-CmC revealed a qualitatively dose response-curve similar to caffeine. A correlation index of r = 0.79 for the concentration thresholds underlined the strong concordance of the caffeine and the 4-CmC effects. The optimal threshold concentration was determined to be 75 microM in the pooled data of all centers and is much lower than that of caffeine (2 mM), suggesting a more than 25-fold higher affinity of 4-CmC. The predictive value of 4-CmC is as high as that of caffeine and consequently higher than that of halothane. 4-CmC seems to be a suitable drug to refine diagnosis of MH susceptibility and could be used as an additional test substance. IMPLICATIONS: Although in vitro contracture testing for malignant hyperthermia diagnosis is well standardized, with a relatively high sensitivity and specificity, false test results cannot be excluded and may be associated with serious disabilities for the concerned individuals. In this multicenter study, 4-chloro-m-cresol was evaluated as a new test substance for the in vitro contracture testing. Its use improves the accuracy of in vitro diagnosis of malignant hyperthermia susceptibility.

Caffeine↗

PubMed2000

Propofol/sufentanil anesthesia suppresses the metabolic and endocrine response during, not after, lower abdominal surgery.

UNLABELLED: We investigated the influence of propofol/sufentanil anesthesia on metabolic and endocrine responses during, and immediately after, lower abdominal surgery. Twenty otherwise healthy patients undergoing abdominal hysterectomy for benign myoma received either continuous infusions of propofol supplemented with sufentanil (0.01 microg. kg(-1). min(-1), n = 10) or enflurane anesthesia (enflurane, n = 10). Plasma concentrations of glucose, lactate, free fatty acids, triglycerides, insulin, glucagon, cortisol, epinephrine, and norepinephrine were measured before, during, and 2 h after surgery. Pre- and postoperative endogenous glucose production (R(a) glucose) was analyzed by an isotope dilution technique by using [6,6-(2)H(2)] glucose. Propofol/sufentanil anesthesia prevented the increase in plasma cortisol and catecholamine concentrations and attenuated the hyperglycemic response during surgery without showing any difference after the operation. Mediated through a higher glucagon/insulin quotient (propofol/sufentanil 15 +/- 7 versus enflurane 8 +/- 4 pg/microU, P < 0.05), the R(a) glucose postoperatively increased more in the propofol/sufentanil than in the enflurane group (propofol/sufentanil 15.6 +/- 2.0 versus enflurane 13.4 +/- 2.2 micromol. kg(-1). min(-1), P < 0.05). IMPLICATIONS: The concept of stress-free anesthesia using propofol combined with sufentanil is valid only during surgery. The metabolic endocrine stress response 2 h after the operation is more pronounced than after inhaled anesthesia.

Anesthesia, Intravenous↗

PubMed2000

Xenon does not alter cardiac function or major cation currents in isolated guinea pig hearts or myocytes.

BACKGROUND: The noble gas xenon (Xe) has been used as an inhalational anesthetic agent in clinical trials with little or no physiologic side effects. Like nitrous oxide, Xe is believed to exert minimal unwanted cardiovascular effects, and like nitrous oxide, the vapor concentration to achieve 1 minimum alveolar concentration (MAC) for Xe in humans is high, i.e., 70-80%. In the current study, concentrations of up to 80% Xe were examined for possible myocardial effects in isolated, erythrocyte-perfused guinea pig hearts and for possible effects on altering major cation currents in isolated guinea pig cardiomyocytes. METHODS: Isolated guinea pigs hearts were perfused at 70 mm Hg via the Langendorff technique initially with a salt solution at 37 degrees C. Hearts were then perfused with fresh filtered (40-microm pore) and washed canine erythrocytes diluted in the salt solution equilibrated with 20% O2 in nitrogen (control), with 20% O2, 40% Xe, and 40% N2, (0.5 MAC), or with 20% O2 and 80% Xe (1 MAC), respectively. Hearts were perfused with 80% Xe for 15 min, and bradykinin was injected into the blood perfusate to test endothelium-dependent vasodilatory responses. Using the whole-cell patch-clamp technique, 80% Xe was tested for effects on the cardiac ion currents, the Na+, the L-type Ca2+, and the inward-rectifier K+ channel, in guinea pig myocytes suffused with a salt solution equilibrated with the same combinations of Xe, oxygen, and nitrogen as above. RESULTS: In isolated hearts, heart rate, atrioventricular conduction time, left ventricular pressure, coronary flow, oxygen extraction, oxygen consumption, cardiac efficiency, and flow responses to bradykinin were not significantly (repeated measures analysis of variance, P>0.05) altered by 40% or 80% Xe compared with controls. In isolated cardiomyocytes, the amplitudes of the Na+, the L-type Ca2+, and the inward-rectifier K+ channel over a range of voltages also were not altered by 80% Xe compared with controls. CONCLUSIONS: Unlike hydrocarbon-based gaseous anesthetics, Xe does not significantly alter any measured electrical, mechanical, or metabolic factors, or the nitric oxide-dependent flow response in isolated hearts, at least partly because Xe does not alter the major cation currents as shown here for cardiac myocytes. The authors' results indicate that Xe, at approximately 1 MAC for humans, has no physiologically important effects on the guinea pig heart.

Action Potentials↗

PubMed2000

Norepinephrine and N(G)-monomethyl-L-arginine in hyperdynamic septic shock in pigs: effects on intestinal oxygen exchange and energy balance.

OBJECTIVES: To compare the effects of norepinephrine (NOR) and the nonselective nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), on intestinal blood flow, oxygen exchange, and energy metabolism over 24 hrs of hyperdynamic, normotensive porcine endotoxic shock. DESIGN: Prospective, randomized, experimental study with repeated measures. SETTING: Investigational animal laboratory. SUBJECTS: Twenty-seven pigs were divided into three groups: seven animals received no vasopressor therapy (ETX) during endotoxic shock; ten animals were treated with NOR; and ten animals were treated with L-NMMA. INTERVENTIONS: Pigs were anesthetized, mechanically ventilated, and instrumented. Eight hours later, endotoxic shock was initiated by an infusion of Escherichia coli lipopolysaccharide. Animals were resuscitated by hetastarch directed to maintain the intrathoracic blood volume and a mean arterial pressure (MAP) of >60 mm Hg. Twelve hours after the start of the endotoxin infusion, NOR or L-NMMA was administered for 12 hrs in the treatment groups to maintain a MAP at preshock levels. MEASUREMENTS AND MAIN RESULTS: ETX caused a continuous fall in MAP, despite a sustained increase in the cardiac output achieved by fluid resuscitation. NOR maintained MAP at preshock levels because of a further rise in cardiac output, whereas hemodynamic stabilization during L-NMMA resulted from systemic vasoconstriction. NOR increased portal venous blood flow concomitant with decreased intestinal oxygen extraction, whereas L-NMMA influenced neither portal venous blood flow nor intestinal oxygen extraction. Mean capillary hemoglobin oxygen saturation of the ileal mucosa as well as the frequency distributions reflecting microcirculatory oxygen availability remained unchanged as well. Nevertheless, portal venous pH similarly decreased and portal venous lactate/pyruvate ratios increased in all three groups. The arterial-ileal mucosal PCO2 gap progressively increased in the ETX and L-NMMA groups, whereas NOR blunted this response. CONCLUSIONS: Neither treatment could reverse the ETX-induced derangements of cellular energy metabolism as reflected by the increased portal venous lactate/pyruvate ratios. The NOR-induced attenuation of ileal mucosal acidosis was possibly caused by a different pattern of blood flow redistribution compared with L-NMMA.

Animals↗

PubMed2000

Effects of the combined thromboxane receptor antagonist and synthase inhibitor DTTX-30 on intestinal O2-exchange and energy metabolism during hyperdynamic porcine endotoxemia.

Sepsis may lead to deranged thromboxane-prostacyclin ratio with consecutive organ dysfunction. Because of the suggested role of the gut in the pathogenesis of septic shock and multiple organ failure, we investigated the effects of the novel dual thromboxane synthase inhibitor and receptor antagonist DTTX-30 (TRASI) on intestinal tissue perfusion, O2 kinetics, and energy metabolism over 24 h of hyperdynamic, normotensive porcine endotoxemia. Before, 12, 18, and 24 h after starting continuous i.v. endotoxin (LPS), we measured portal venous (PV) blood flow, intestinal oxygen extraction (iO2ER), intracapillary hemoglobin O2 saturation (HbO2%) of the ileal wall, intramucosal ileal PCO2, PV lactate-pyruvate (L-P) ratio, and plasma levels of thromboxane and prostacyclin. Treatment with TRASI (0.12 mg/kg i.v. bolus injection followed by an infusion of 0.29 mg/kg/h) initiated after 12 h of LPS infusion markedly reduced the plasma thromboxane levels and attenuated the LPS-induced fall in systemic vascular resistance, resulting in hemodynamic stabilization. TRASI did not influence the LPS-induced increase in PV blood flow nor intracapillary HbO2%, thus reflecting unchanged microcirculatory O2 availability and decreased iO2ER, possibly because of reduced O2 requirements. Nevertheless, TRASI prevented the LPS-induced increase in the PV L-P ratio, attenuated the progression of the ileal mucosal-arterial PCO2 gap, and tended to attenuate the gradual fall of PV pH. Hence, compounds like TRASI may beneficially influence LPS-related derangements of gut energy metabolism.

Animals↗

PubMed2000

Effect of a dopexamine-induced increase in cardiac index on splanchnic hemodynamics in septic shock.

In 12 patients with hyperdynamic septic shock we studied the effect of dopexamine, a combined dopamine and beta-adrenergic agonist, on hepatosplanchnic hemodynamics and O(2) exchange. All patients required noradrenaline to maintain mean arterial pressure > 60 mm Hg (noradrenaline >/= 0.04 microg x kg(-1) x min(-1)) with a cardiac index >/= 3.0 L/min/m(2). Splanchnic blood flow (Qspl) was measured using primed continuous infusion of indocyanine green dye with hepatic venous sampling. In addition tonometric gastric mucosal-arterial and gastric mucosal-hepatic venous P CO(2) gradients were assessed as indicators of regional energy balance. After 90 min of stable hemodynamics a first measurement was obtained. Then dopexamine infusion was titrated (1-4 microg x kg(-1) x min(-1)) to increase cardiac output by approximately 25% (20-30%). After 90 min all measurements were repeated, and dopexamine was withdrawn followed by a third measurement. Median Qspl (0.86/1.23-0. 66 versus 0.96/1.42-0.85 L/min/m (2) [median value/25th-75th percentiles], p < 0.05) increased whereas the fractional contribution of Qspl to total blood flow decreased (21/28-13 versus 19/28-12%, p < 0.05). Although both global and regional oxygen delivery (DO(2)) consistently increased, neither global or regional V O(2) nor PCO(2) gradients were significantly affected. In patients with septic shock and ongoing noradrenaline treatment dopexamine seems to have no preferential effects on hepatosplanchnic hemodynamics, O(2) exchange, or energy balance.

Cardiac Output↗

PubMed2000

Neurocognitive sequelae of infants of diabetic mothers.

On the basis of animal models, it was hypothesized that infants of diabetic mothers (IDMs) would be at risk for suffering damage to the hippocampus primarily because of fetal iron deficiency, chronic hypoxia, and hypoglycemia. This, in turn, may result in impairments in recognition memory at a young age. To test this model, the memory of 6-month-old IDMs and control infants was evaluated with electrophysiological (event-related potential [ERP]) and behavioral (looking time) measures. At 12 months, the Bayley Scales of Infant Development was administered. Our ERP measures showed robust evidence consistent with memory deficits in the IDMs. In contrast, the looking time measures and the Bayley exam failed to distinguish between the groups. From these results it was concluded that the ERP, but not the behavioral, measures are able to detect, in an at-risk population, deficits in recognition memory that are thought to be mediated by damage to the hippocampus.

Cognition Disorders↗

PubMed1999

Time of peritoneal cavity exposure influences postoperative glucose production.

PURPOSE: To examine the effect of the duration of peritoneal cavity exposure on glucose metabolism after abdominal surgery. METHODS: In eight otherwise healthy patients (ASA 1) with uterine myoma, endogenous glucose production (Ra glucose) was measured immediately before and two hours after abdominal hysterectomy by a stable isotope dilution technique using primed continuous infusions of [6,6-2H2]-glucose. Plasma concentrations of glucose, lactate, insulin, glucagon, cortisol, epinephrine and norepinephrine were determined before, during (5 and 60 min after peritoneal incision, skin closure) and two hours after surgery. Pre- and postoperative glucose clearance was calculated as Ra glucose divided by plasma glucose concentration. RESULTS: Ra glucose increased from 11.8 +/- 1.2 to 16.8 +/- 3.2 micromol x kg(-1) x min(-1) two hours after hysterectomy (P < 0.05) with a correlation between the degree of increase and the time of peritoneal cavity exposure (r = 0.859, P = 0.006). Plasma glucose concentration increased after surgery from 4.7 +/- 0.8 to 8.3 +/- 1.9 mmol x l(-1) (P < 0.05), while glucose clearance decreased from 2.6 +/- 0.4 to 2.1 +/- 0.4 ml x kg(-1) x min(-1) (P < 0.05). Plasma concentrations of cortisol and catecholamines increased after hysterectomy (cortisol from 6 +/- 2 to 31 +/- 7 microg x dl(-1), epinephrine from 25 +/- 14 to 205 +/- 132 pg x ml(-1), norepinephrine from 182 +/- 82 to 377 +/- 132 pg x ml(-1), P < 0.05), whereas plasma lactate, insulin and glucagon concentrations remained unchanged. CONCLUSION: The magnitude of increase of glucose production after abdominal hysterectomy is associated with the duration of peritoneal cavity exposure.

Adult↗

PubMed1999

[The effect of low droperidol dosages on postoperative anxiety, internal tension, general mood and PONV].

BACKGROUND: Droperidol even in low doses such as 0.5 mg to 1.25 mg can increase postoperative anxiety and state of tension. The aim of this study was to determine whether these side effects occur frequently following low-dose droperidol and to see whether these are dose related. METHODS: 184 female in- and outpatients ASA grade 1 and 2 undergoing gynaecological laparoscopy were recruited to this prospective, double-blind study. General anaesthesia was standardized (induction with thiopentone, fentanyl 2 micrograms/kg and vecuronium 0.1 mg/kg, tracheal intubation, maintainance with enflurane in N2O/O2). Patients were randomly allocated to receive saline (n = 45), 0.625 mg (n = 46), 1.25 mg (n = 47) or 2.5 mg (n = 46) droperidol i.v. 10 minutes before the end of surgery. 1,3,6, and 24 hours postoperatively, the patients' anxiety, state of tension and overall mood was evaluated using two psychological questionnaires which had been tested for the perioperative period (Erlanger anxiety and tension-scale/BSKE-EWL-test). Sedation was evaluated by the staff of the recovery room. In addition, postoperative nausea and vomiting (PONV) was assessed using a 100 mm visual analogue scale and by counting the episodes of retching or vomiting. PONV was then rated over the whole observation period as none, mild, moderate or severe using a fixed scoring algorithm. Statistical analysis was performed using the ANOVA and the chi2-test. RESULTS: The patients did not differ with regard to biometric data, duration of surgery and anaesthesia. The postoperative scores for anxiety, state of tension and overall mood were not different between the groups at any observation time (Fig. 1: anxiety and tension: P = 0.5687; figure 2: overall mood: P = 0.0647). Quality of sleep in the first night after surgery was the same in all groups (Table 2 and 3). Sedation was not significantly different (Table 4; P = 0.0704). Furthermore, duration of stay in the recovery room did not differ (P = 0.4353). On the other hand, three patients from the 2.5 mg droperidol group had to stay unexpectedly on the ward overnight, because they had been too much sedated to be discharged at home. This was not the case with any patient from the other groups. Compared to placebo, PONV over the whole 24 h observation period was significantly reduced by droperidol (Fig. 3; P = 0.0338): completely free from PONV: placebo: 41.3%, 0.625 mg droperidol: 67.4%, 1.25 mg droperidol: 53.2%, 2.5 mg droperidol: 71.7%. Also the severity of PONV was reduced. CONCLUSION: In gynaecological laparoscopy under general anaesthesia with tracheal intubation, we recommend droperidol 0.625 mg in the prevention of PONV, as it reduces PONV as well as 2.5 mg with no severe sedation in this dosage. Psychological side effects did not occur more frequently after droperidol compared to placebo in any of the investigated dosages.

Adjuvants, Anesthesia↗