Postoperative vomiting in pediatric oncologic patients: prediction by a fuzzy logic model.

OBJECTIVE: To report a fuzzy logic mathematical model to predict postoperative vomiting (POV) in pediatric oncologic patients and compare with preexisting scores. BACKGROUND: Although POV has a high incidence in children and may decrease parental satisfaction after surgeries, there is only one specific score that predicts POV in children: the Eberhart's score. In this study, we report a fuzzy model that intends to predict the probability of POV in pediatric oncologic patients. Fuzzy logic is a mathematical theory that recognizes more than simple true and false values and takes into account levels of continuous variables such as age or duration of the surgery. The fuzzy model tries to account for subjectiveness in the variables. METHODS: Preoperative potential risk factors for POV in 198 children (0-19 year old) with malignancies were collected and analyzed. Data analysis was performed with the chi-square test and logistic regression to evaluate probable risk factors for POV. A system based on fuzzy logic was developed with the risk factors found in the logistic regression, and a computational interface was created to calculate the probability of POV. RESULTS: The model showed a good performance in predicting POV. After the analysis, the model was compared with Eberhart's score in the same population and showed a better performance. CONCLUSIONS: The fuzzy score can predict the chance of POV in children with cancer with good accuracy, allowing better planning for postoperative prophylaxis of vomiting. The computational interface is available for free download at the internet and is very easy to use.

Hemodynamic effects of local anesthetics intoxication: experimental study in swine with levobupivacaine and bupivacaine.

PURPOSE: To compare the hemodynamic repercussions following a toxic dose of levobupivacaine and bupivacaine intravascularly injected in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation was performed and mechanical ventilation was instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter). After a 30-minute resting period, the animals were randomly divided into two groups in a double-blinded fashion and received a bolus injection of 4 mg/kg of either agent for intoxication. Hemodynamic results were then evaluated at 1, 5, 10, 15, 20 and 30 minutes. RESULTS: Levobupivacaine had greater hemodynamic repercussions than racemic bupivacaine. These results disagree with those found when the levorotatory isomer of bupivacaine was used in humans, but are in agreement with recently reported findings in animals. CONCLUSION: Levobupivacaine was shown to be more toxic in pigs than racemic bupivacaine when large doses are injected intravenously.

[Haemodynamic effects of intoxication with bupivacaine and enantiomeric excess mixture. Experimental study in swine]. / Efeitos hemodinâmicos da intoxicação aguda com bupivacaína e a mistura enantiomérica--estudo experimental em suínos.

BACKGROUND: Racemic bupivacaine has been the local anaesthetic of choice in regional blocks due to quality and duration of anesthesia. However its cardiovascular toxicity has been a source of concern and research has been made for lesser impact drugs. One choice is its levogyre isomer, levobupivacaine, apparently less cardiotoxic due a lower affinity to the heart sodium channels. In Brazil, a drug containing 75% of levogyre isomer and 25% of dextrogyre isomer, called enantiomeric excess mixture, is available. This study intends to evaluate haemodynamic effects of the intravascular injection of a toxic dose of both agents in swine. METHODS: Large White pigs were anaesthetized with thiopental, intubated and placed on mechanical ventilation. Haemodynamic monitoring was performed with an invasive blood pressure and Swan-Ganz catheter on a pulmonary artery. After a 30 minute rest period, animals were randomly divided in two groups and the intoxication was performed on a double-blind method with 4 mg.kg-1 of one of the drugs. Haemodynamic parameters were then evaluated at 1, 5, 10, 15, 20 and 30 minutes. RESULTS: The enantiomeric excess mixture caused greater haemodynamic effects than the racemic bupivacaine. These results diverge from those found in humans with levogyre isomer but are similar to recent results reported in animals. Care should be taken when extrapolating data obtained in swine to humans and further research is necessary. CONCLUSION: When high doses are injected in swine, the enantiomeric excess mixture was more toxic than the racemic bupivacaine.

Hemodynamic changes with high infusion rates of lipid emulsion. Experimental study in swine.

PURPOSE: To evaluate hemodynamic changes caused by sole intravenous infusion of lipid emulsion with doses recommended for treatment of drug-related toxicity. METHODS: Large White pigs underwent general anesthesia, tracheal intubation was performed, and mechanical ventilation was instituted. Hemodynamic variables were recorded using invasive blood pressure and pulmonary artery catheterization. Baseline hemodynamic measurements were obtained after a 30-minute stabilization period. An intravenous bolus injection of 20% lipid emulsion at 1.5 ml/kg was administered. Additional hemodynamic measurements were made after 1 minute, followed by a continuous intravenous lipid infusion of 0.25 ml/kg/min. Further measurements were carried out at 10, 20 and 30 minutes, when the infusion was doubled to 0.5 ml/kg/min. Assessment of hemodynamic changes were then made at 40, 50 and 60 minutes. RESULTS: Lipid infusion did not influence cardiac output or heart rate, but caused an increase in arterial blood pressure, mainly pulmonary blood pressure due to increased vascular resistance. Ventricular systolic stroke work consequently increased with greater repercussions on the right ventricle. CONCLUSION: In doses used for drug-related toxicity, lipid emulsion cause significant hemodynamic changes with hypertension, particularly in the pulmonary circulation and increase in vascular resistance, which is a factor to consider prior to use of these solutions.

Hemodynamic changes with two lipid emulsions for treatment of bupivacaine toxicity in swines.

PURPOSE: To compare the hemodynamic changes following two different lipid emulsion therapies after bupivacaine intoxication in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation performed and mechanical ventilation instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter). After a 30-minute resting period, 5 mg.kg-1 of bupivacaine by intravenous injection was administered and new hemodynamic measures were performed 1 minute later; the animals were than randomly divided into three groups and received 4 ml.kg-1 of one of the two different lipid emulsion with standard long-chaim triglyceride, or mixture of long and medium-chain triglyceride, or saline solution. Hemodynamic changes were then re-evaluated at 5, 10, 15, 20 and 30 minutes. RESULTS: Bupivacaine intoxication caused fall in arterial blood pressure, cardiac index, ventricular systolic work index mainly and no important changes in vascular resistances. Both emulsion improved arterial blood pressure mainly increasing vascular resistance since the cardiac index had no significant improvement. On the systemic circulation the hemodynamic results were similar with both lipid emulsions. CONCLUSION: Both lipid emulsions were efficient and similar options to reverse hypotension in cases of bupivacaine toxicity.

[Treatment of status migrainosus by general anesthesia: a case report]. / Tratamento do estado de mal-enxaquecoso pela anestesia geral: relato de caso.

BACKGROUND AND OBJECTIVES: The status migrainosus is a complication of migraine characterizedby severe headache for more than 72 h that did not respond to treatment, with risk of strokeand suicide. Researches on treatment are directed to drugs that stimulate GABA receptors; propofol and isoflurane act on sub-GABAa receptors and theoretically could be interesting. The first has been the subject of research in severe migraine. Opioids are employed in pain, and its use in chronic headache is debatable, but these agents are employed in acute cases. The goalis to present a case of refractory status migrainosus in that we decided to break the pain cycle by general anesthesia. CASE REPORT: Female patient, aged 50 years, with status migrainosus, in the last five days withvisits to the emergency department, medicated parenterally with various agents without result. Without comorbidities, dehydrated, described her pain as "well over 10" in Visual NumericScale (VNS). After consulting the literature, and given the apparent severity of the condition, we opted for a general anesthesia: induction with fentanyl, propofol, and vecuroniumand maintenance with isoflurane and propofol for two hours. Following the treatment, in the postanesthetic recuperation (PAR), the patient related her pain as VNS 3, and was released after five hours with VNS 2. Subsequently, her preventive treatment was resumed. CONCLUSION: Status migrainosus is a rare disabling complication and anesthetics have been the subject of research in its treatment; the option for general anesthesia with agents that stimulate GABA receptors, propofol and isoflurane, in association with fentanyl, proved effective and should encourage new research.

Treatment of status migrainosus by general anesthesia: a case report.

BACKGROUND AND OBJECTIVES: The status migrainosus is a complication of migraine characterized by severe headache for more than 72h that did not respond to treatment, with risk of stroke and suicide. Researches on treatment are directed to drugs that stimulate GABA receptors; propofol and isoflurane act on sub-GABAa receptors and theoretically could be interesting. The first has been the subject of research in severe migraine. Opioids are employed in pain, and its use in chronic headache is debatable, but these agents are employed in acute cases. The goal is to present a case of refractory status migrainosus in that we decided to break the pain cycle by general anesthesia. CASE REPORT: Female patient, aged 50 years, with status migrainosus, in the last five days with visits to the emergency department, medicated parenterally with various agents without result. Without comorbidities, dehydrated, described her pain as "well over 10" in Visual Numeric Scale (VNS). After consulting the literature, and given the apparent severity of the condition, we opted for a general anesthesia: induction with fentanyl, propofol, and vecuronium and maintenance with isoflurane and propofol for two hours. Following the treatment, in the postanesthetic recuperation (PAR), the patient related her pain as VNS 3, and was released after five hours with VNS 2. Subsequently, her preventive treatment was resumed. CONCLUSION: Status migrainosus is a rare disabling complication and anesthetics have been the subject of research in its treatment; the option for general anesthesia with agents that stimulate GABA receptors, propofol and isoflurane, in association with fentanyl, proved effective and should encourage new research.

[Civil, criminal and ethical liability of medical doctors]. / Responsabilidade Civil, Penal e Etica dos médicos.

In the last years doctors have been the target of a growing number of civil, criminal law suits, as well as ethical procedures. Medicine is a widely targeted career, not only owing to its inherent risks, but also owing to a mistaken approach of the Judiciary Power about the obligations of medical doctors. Decisions of the Medical Board in ethical procedures have an impact in civil and criminal justice and therefore should be followed closely. The purpose of this review is to provide a wide view from a doctor-lawyer perspective of cases involving civil, criminal liability of anesthesiologists as well as ethical procedures against them, in an effort to make them comprehensible to doctors. After a brief historical introduction civil liability foundations and legal articles are examined. Responsibilities of doctors, hospitals and health insurance providers are discussed separately, as well as reparation mechanisms. Crimes possible to occur during medical practice and respective penalties are described; the direct relationship between crime and civil reparation is demonstrated. The administrative nature of ethical procedure is described, emphasizing that the legal character of its penalties often serve as grounds for civil and criminal justice decisions. Prevention is still the best medicine. Good medical practice and a good medical-patient relationship are still the best ways to minimize lawsuits and their repercussions. Doctors should have some knowledge of juridical mechanisms in lawsuits and ethical procedures, but should not take defense initiatives without prior consultation of an attorney. Civil, criminal and ethical liability of physicians.

Lipid therapy with two agents in ropivacaine-induced toxicity: experimental study in Swine.

BACKGROUND AND OBJECTIVE: Compare hemodynamic changes after ropivacaine-induced toxicity followed by treatment with two lipid emulsions in swine. METHODS: Large White pigs were anesthetized with thiopental, followed by intubation, and kept on mechanical ventilation. Hemodynamic variables at rest were recorded with invasive pressure monitoring and pulmonary artery catheterization. After 30 minutes, 7mg.kg(-1) ropivacaine were injected intravenously and new hemodynamic measurements were performed within one minute. The animals were then randomly allocated into three groups and received: 4mL.kg(-1) saline solution, or 4mL.kg(-1) lipid emulsion with long-chain triglycerides, or 4mL.kg(-1) lipid emulsion with longand medium-chain triglycerides. Hemodynamic changes were reevaluated at 5, 10, 15, 20 and 30 minutes. RESULTS: Ropivacaine-induced toxicity mainly caused a drop in blood pressure and cardiac index without significant changes in vascular resistance. Therapy with lipid emulsions restored blood pressure primarily through increased vascular resistance, as cardiac index showed no significant improvement. Lipid emulsion with medium-chain triglycerides caused a greater increase in vascular resistance, particularly pulmonary. CONCLUSION: In groups receiving lipid emulsions, hemodynamic results were better than in control group. There were no differences in systemic arterial pressure and cardiac index between animals receiving lipid emulsion with long-chain triglycerides and mixed long- and medium-chain triglycerides.

Hemodynamic changes in lipid emulsion therapy (SMOFlipid) for bupivacaine toxicity in swines.

PURPOSE: To evaluate the hemodynamic changes following SMOFlipid emulsion therapy with after bupivacaine intoxication in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation was performed and mechanical ventilation was instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter). After a 30-minute resting period, 5 mg.kg(-1) of bupivacaine by intravenous injection was administered and new hemodynamic measures were performed 1 minute later; the animals were than randomly divided into two groups and received 4 ml.kg(-1) of saline solution or 4 ml.kg(-1) of SMOFlipid emulsion 20%. Hemodynamic changes were then re-evaluated at 5, 10, 15, 20 and 30 minutes. RESULTS: Bupivacaine intoxication caused fall in arterial blood pressure, cardiac index, ventricular systolic work index mainly and no important changes in vascular resistances. SMOFlipid emulsion therapy was able to improve blood pressure mainly by increasing vascular resistance since the cardiac index had no significant improvement in our study. Hemodynamic results of the use of lipid emulsion in bupivacaine intoxication were better than the control group. CONCLUSION: The SMOFlipid emulsion is a option for reversing hypotension in cases of intoxication by bupivacaine.

Lipids in local anesthetic toxicity.

INTRODUCTION: With the advent of long-lasting local anesthetics, local and regional anesthesia gained considerable impetus and the use of these techniques has become increasingly widespread. New block techniques have been described and regional anesthesia is frequently associated with general anesthesia to provide postoperative analgesia. In contrast, large doses of local anesthetics are required with the risk of accidents due to inadvertent intravascular injection, which is a severe complication without a specific treatment until a few years ago. In 1998, the use of lipid emulsions was proposed in animals. Since 2006, many studies have demonstrated an interest in these solutions in cases of local anesthetic-induced toxicity with a decrease in morbidity and mortality. The aim of this review article was to research the methodology, reviewing mechanisms, interests, limitations and currently recommended treatment. METHOD: Some historical references on local anesthetics, articles published during the last 30 years in journals indexed in Medline and in two textbooks were reviewed. Articles on local anesthetic toxicity, lipid emulsion therapy, review articles on the topic and treatment adopted in diverse services and countries were selected, producing a summary. CONCLUSIONS: It is no longer necessary to show the effectiveness and interest in lipid emulsion therapy for local anesthetic toxicity. Various specialty societies have already published their guidelines and advice about stocking these products in any setting in which local and regional anesthetic techniques are practiced.

Methadone and morphine during anesthesia induction for cardiac surgery. Repercussion in postoperative analgesia and prevalence of nausea and vomiting.

BACKGROUND AND OBJECTIVES: Pain is an aggravating factor in postoperative morbidity and mortality especially in large size surgeries. Methods to effectively fend pain collide with elevated costs and for this reason they are not accessible in every service. The option would be the use of an opioid with long half-life, such as methadone. The objective of the present study was to compare the requirements of postoperative analgesia in patients who received methadone, morphine, or placebo during anesthetic induction, besides the prevalence of postoperative nausea and vomiting. METHODS: Fifty-five patients scheduled for cardiac surgery were divided into three groups and they received during anesthetic induction 20mg of methadone, 20mg of morphine, or placebo. At the end of surgery, patients were transferred to the ICU where the following parameters were evaluated: duration of anesthesia, time until extubation, time until the need of the first analgesic, number of doses required in 24 hours, assessment of analgesia by the patient, and prevalence of nausea/vomiting. RESULTS: Differences in the duration of anesthesia and time until extubation were not observed. The first dose of analgesic in patients who received methadone was administered later than in patients in the other two groups. The need of analgesics in the methadone group was lower, quality of analgesia was better, and prevalence of nausea and vomiting was also lower. CONCLUSIONS: Methadone during anesthetic induction was effective for analgesia in large size surgeries. Lower incidence of nausea and vomiting was observed in the methadone group and therefore it is a low cost option available among us that should be stimulated.

Hemodynamic changes with high infusion rates of lipid emulsion. Experimental study in swine

To evaluate hemodynamic changes caused by sole intravenous infusion of lipid emulsion with doses recommended for treatment of drug-related toxicity. METHODS: Large White pigs underwent general anesthesia, tracheal intubation was performed, and mechanical ventilation was instituted. Hemodynamic variables were recorded using invasive blood pressure and pulmonary artery catheterization. Baseline hemodynamic measurements were obtained after a 30-minute stabilization period. An intravenous bolus injection of 20% lipid emulsion at 1.5 ml/kg was administered. Additional hemodynamic measurements were made after 1 minute, followed by a continuous intravenous lipid infusion of 0.25 ml/kg/min. Further measurements were carried out at 10, 20 and 30 minutes, when the infusion was doubled to 0.5 ml/kg/min. Assessment of hemodynamic changes were then made at 40, 50 and 60 minutes. RESULTS: Lipid infusion did not influence cardiac output or heart rate, but caused an increase in arterial blood pressure, mainly pulmonary blood pressure due to increased vascular resistance. Ventricular systolic stroke work consequently increased with greater repercussions on the right ventricle. CONCLUSION: In doses used for drug-related toxicity, lipid emulsion cause significant hemodynamic changes with hypertension, particularly in the pulmonary circulation and increase in vascular resistance, which is a factor to consider prior to use of these solutions.(AU)

Hemodynamic changes with two lipid emulsions for treatment of bupivacaine toxicity in swines

PURPOSE: To compare the hemodynamic changes following two different lipid emulsion therapies after bupivacaine intoxication in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation performed and mechanical ventilation instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter). After a 30-minute resting period, 5 mg.kg-1 of bupivacaine by intravenous injection was administered and new hemodynamic measures were performed 1 minute later; the animals were than randomly divided into three groups and received 4 ml.kg-1 of one of the two different lipid emulsion with standard long-chaim triglyceride, or mixture of long and medium-chain triglyceride, or saline solution. Hemodynamic changes were then re-evaluated at 5, 10, 15, 20 and 30 minutes. RESULTS: Bupivacaine intoxication caused fall in arterial blood pressure, cardiac index, ventricular systolic work index mainly and no important changes in vascular resistances. Both emulsion improved arterial blood pressure mainly increasing vascular resistance since the cardiac index had no significant improvement. On the systemic circulation the hemodynamic results were similar with both lipid emulsions. CONCLUSION: Both lipid emulsions were efficient and similar options to reverse hypotension in cases of bupivacaine toxicity. .

Hemodynamic changes with high infusion rates of lipid emulsion. Experimental study in swine

PURPOSE: To evaluate hemodynamic changes caused by sole intravenous infusion of lipid emulsion with doses recommended for treatment of drug-related toxicity. METHODS: Large White pigs underwent general anesthesia, tracheal intubation was performed, and mechanical ventilation was instituted. Hemodynamic variables were recorded using invasive blood pressure and pulmonary artery catheterization. Baseline hemodynamic measurements were obtained after a 30-minute stabilization period. An intravenous bolus injection of 20% lipid emulsion at 1.5 ml/kg was administered. Additional hemodynamic measurements were made after 1 minute, followed by a continuous intravenous lipid infusion of 0.25 ml/kg/min. Further measurements were carried out at 10, 20 and 30 minutes, when the infusion was doubled to 0.5 ml/kg/min. Assessment of hemodynamic changes were then made at 40, 50 and 60 minutes. RESULTS: Lipid infusion did not influence cardiac output or heart rate, but caused an increase in arterial blood pressure, mainly pulmonary blood pressure due to increased vascular resistance. Ventricular systolic stroke work consequently increased with greater repercussions on the right ventricle. CONCLUSION: In doses used for drug-related toxicity, lipid emulsion cause significant hemodynamic changes with hypertension, particularly in the pulmonary circulation and increase in vascular resistance, which is a factor to consider prior to use of these solutions.

Hemodynamic changes with two lipid emulsions for treatment of bupivacaine toxicity in swines

PURPOSE: To compare the hemodynamic changes following two different lipid emulsion therapies after bupivacaine intoxication in swines. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation performed and mechanical ventilation instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization (Swan-Ganz catheter). After a 30-minute resting period, 5 mg.kg-1 of bupivacaine by intravenous injection was administered and new hemodynamic measures were performed 1 minute later; the animals were than randomly divided into three groups and received 4 ml.kg-1 of one of the two different lipid emulsion with standard long-chaim triglyceride, or mixture of long and medium-chain triglyceride, or saline solution. Hemodynamic changes were then re-evaluated at 5, 10, 15, 20 and 30 minutes. RESULTS: Bupivacaine intoxication caused fall in arterial blood pressure, cardiac index, ventricular systolic work index mainly and no important changes in vascular resistances. Both emulsion improved arterial blood pressure mainly increasing vascular resistance since the cardiac index had no significant improvement. On the systemic circulation the hemodynamic results were similar with both lipid emulsions. CONCLUSION: Both lipid emulsions were efficient and similar options to reverse hypotension in cases of bupivacaine toxicity.(AU)

Treatment of status migrainosus by general anesthesia: a case report / Tratamento do estado de mal-enxaquecoso pela anestesia geral: relato de caso

ABSTRACTBACKGROUND AND OBJECTIVES: The status migrainosus is a complication of migraine characterized by severe headache for more than 72 h that did not respond to treatment, with risk of stroke and suicide. Researches on treatment are directed to drugs that stimulate GABA receptors; propofol and isoflurane act on sub-GABAa receptors and theoretically could be interesting. The first has been the subject of research in severe migraine. Opioids are employed in pain, and its use in chronic headache is debatable, but these agents are employed in acute cases. The goal is to present a case of refractory status migrainosus in that we decided to break the pain cycle by general anesthesia.CASE REPORT: Female patient, aged 50 years, with status migrainosus, in the last five days with visits to the emergency department, medicated parenterally with various agents without result. Without comorbidities, dehydrated, described her pain as "well over 10" in Visual Numeric Scale (VNS). After consulting the literature, and given the apparent severity of the condition, we opted for a general anesthesia: induction with fentanyl, propofol, and vecuronium and maintenance with isoflurane and propofol for two hours. Following the treatment, in the postanesthetic recuperation (PAR), the patient related her pain as VNS 3, and was released after five hours with VNS 2. Subsequently, her preventive treatment was resumed.CONCLUSION: Status migrainosus is a rare disabling complication and anesthetics have been the subject of research in its treatment; the option for general anesthesia with agents that stimulate GABA receptors, propofol and isoflurane, in association with fentanyl, proved effective and should encourage new research.

RESUMOJUSTIFICATIVA E OBJETIVOS: O estado de mal-enxaquecoso é complicação da migrânea caracterizada por cefaleia severa por mais de 72 horas não responsiva à terapêutica com risco de AVC e suicídio. Pesquisas no tratamento se direcionam às drogas que estimulam receptores GABA; propofol e isoflurano atuam nos sub-receptores GABAa e teoricamente poderiam ser interessantes. O primeiro já foi objeto de pesquisas na migrânea severa. Opioides são empregados em dor, seu uso crônico nas cefaleias é discutível, mas são empregados nos casos agudos. O objetivo é apresentar caso de estado de mal-enxaquecoso refratário em que se optou para quebrar o ciclo álgico por uma anestesia geral.RELATO DE CASO: Paciente do sexo feminino com 50 anos em estado de mal-enxaquecoso havia cinco dias com passagens anteriores por serviço de urgências, medicada por via parenteral com vários agentes sem resultado. Sem comorbidades, desidratada, descrevia sua dor como "muito superior a 10" na ENV. Após consulta à literatura, face à gravidade aparente do quadro, optou-se pela feitura de uma anestesia geral; a indução foi com fentanil, propofol, vecurônio e manutenção com isoflurano e propofol por duas horas. No fim, na RPA, no primeiro contato classificou sua dor com ENV 3, teve alta após cinco horas com ENV 2. Ulteriormente retomou seu tratamento preventivo.CONCLUSÃO: O mal-enxaquecoso é uma complicação rara incapacitante e anestésicos têm sido objeto de pesquisas no tratamento; a opção por uma anestesia geral com agentes que estimulam os receptores GABA, propofol e isoflurano, aliados ao fentanil, mostrou-se eficaz e deve incentivar pesquisas.

Hemodynamic effects of volume replacement with saline solution and hypertonic hydroxyethyl starch in dogs.

PURPOSE: To investigate hemodynamic response to volume replacement with saline solution and hypertonic hydroxyethyl starch in hypovolemic dogs. METHODS: Forty dogs under general anesthesia and hemodynamic monitoring, following measurements at baseline, were bled 20 ml x Kg(-1) and parameters were measured again after 10 minutes. The animals were randomly divided in two groups and volume replacement was performed with saline solution twice the volume removed or 4 ml x Kg(-1) of hypertonic hydroxyethyl starch. Hemodynamic data were again measured after 5, 15, 30, 45 and 60 minutes. RESULTS: With both solutions values returned to satisfactory hemodynamic levels. With saline solution, there was a greater amplitude in variations that tended to decrease progressively. With hypertonic hydroxyethyl starch, the parameters studied returned more rapidly to levels similar to those at baseline and varied less. CONCLUSION: Both solutions proved to be efficient at replacing volume in the short period studied, although hypertonic hydroxyethyl starch produced more stable results.

Hemodynamic effects of ropivacaine and levobupivacaine intravenous injection in swines.

PURPOSE: To compare the hemodynamic effects following a toxic dose of either agent after intravenous injection in swines, as might accidentally occur during regional anesthesia in humans. METHODS: Large White pigs were anesthetized with thiopental, tracheal intubation was performed and mechanical ventilation was instituted. Hemodynamic variables were recorded with invasive pressure monitoring and pulmonary artery catheterization. After a 30-minute resting period, the animals were randomly divided into two groups in a double-blinded fashion and received a bolus intravenous injection of 4 mg.kg-1 of either agent. Hemodynamic results were evaluated at rest and 1, 5, 10, 15, 20 and 30 minutes after intoxication. RESULTS: Hemodynamic repressions of acute intoxication with levobupivacaine were more important and more prolonged than those of ropivacaína. CONCLUSION: In pigs, levobupivacaine was shown to be more toxic than ropivacaine when the same large doses are injected intravenously.