Artur Udelsmann

The hemodynamic effects of endothelin receptor antagonism during a venous air infusion in dogs

Endothelin (ET) is involved in the humoral component of the vasoconstriction during pulmonary embolism. We examined the effects of selective ET receptor antagonists on the hemodynamic and respiratory changes and on serum thromboxane B2 (TXB2) levels, during a continuous venous air infusion (VAI) in anesthetized mongrel dogs. The VAI (0.2 mL · kg−1 · min−1) was initiated 5 min after an injection of saline (controls, n = 7), 1 &mgr;mol of the selective ETA receptor antagonist JKC-301 (group A, n = 6), or 1 &mgr;mol of the selective ETB receptor antagonist BQ-788 (group B, n = 6). Hemodynamic evaluation was performed every 15 min of VAI, and blood samples were drawn for blood gas analysis and TXB2 determinations. The increase in pulmonary perfusion pressure after 30 min of VAI was attenuated in Group A compared with the controls and Group B (Group A = 7 ± 1 mm Hg; Group B = 16 ± 1 mm Hg; controls = 14 ± 1 mm Hg;P < 0.05). Pulmonary vascular resistance showed a similar behavior. TXB2 concentrations increased after 60 min of VAI in the controls and in Group B, but not in Group A (controls = 48%; Group B = 104%; Group A = 18%;P < 0.05 for controls and Group B). Similar decreases in PaO2 and SaO2 were observed in the three groups. We conclude that antagonism of ETA receptors attenuates the hemodynamic changes and blunts the increase in thromboxane A2 production during a VAI in dogs. Implications We evaluated the effects of endothelin receptor antagonists during a venous air infusion in dogs. EndothelinA receptor antagonism attenuated the hemodynamic changes and blunted the increase in thromboxane A2 production in this setting.

Responsabilidade Civil, Penal e Ética 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.

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.

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.

Influência da técnica anestésica nas alterações hemodinâmicas no transplante renal: estudo retrospectivo

JUSTIFICATIVA Y OBJETIVOS: El exito en el transplante renal (Tx) depende del tipo de donador, de la duracion de la isquemia fria y de los parametros hemodinamicos en la reperfusion. El objetivo de esta investigacion fue analizar la tecnica anestesica, la incidencia de alteraciones cardiovasculares y el aparecimiento de diuresis en el periodo perioperatorio de los Tx realizados en la UNICAMP. METODO: Se evaluo retrospectivamente Tx de adultos realizados entre enero de 2005 y abril de 2006. Se tuvieron en cuenta los datos demograficos, los examenes laboratoriales preoperatorios, tecnicas y agentes anestesicos, hidratacion, parametros hemodinamicos, el uso de aminas vasoactivas, la presencia de diuresis y complicaciones intraoperatorias, con analisis comparativo entre los subgrupos formados conforme a la tecnica anestesica empleada. Se usaron en el analisis estadistico el test t de Student (parametricos), Mann-Whitney (no parametricos), test del Cui-cuadrado y Exacto de Fisher para la comparacion de proporciones y analisis multivariada. RESULTADOS: Se estudiaron 92 pacientes, 59 con anestesia general (AG) y 33 anestesia general asociada a la epidural (AG + Peri), 42 recibieron rinones de donantes vivos y 50 de fallecidos. No hubo diferencia (p < 0,05) en la mayoria de los parametros preoperatorios estudiados, con excepcion del origen del injerto (82% AG + Peri recibieron rinones de donante fallecido). La alteracion cardiovascular mas frecuente fue la hipotension arterial (30% AG y 48% AG + Peri, p < 0,05). El regimen de hidratacion no fue diferente entre los grupos (86,7 ± 30,2 mL.kg-1 AG y 94,8 ± 21,8 mL.kg-1 AG+Peri, p = 0,38). El injerto del donante fallecido se correlaciono con una mayor inestabilidad hemodinamica y con un peor pronostico para la funcion inmediata del injerto, p < 0,01 y 0,01 respectivamente. Un volumen de hidratacion de 80 mL.kg-1 se asocio a la diuresis (OR = 2,94, IC95% 1,00-8,32). CONCLUSIONES: La tecnica anestesica empleada fue anestesia general, asociada o no a la epidural. La alteracion hemodinamica mas comun fue la hipotension arterial. Se mostraron beneficos con relacion a la diuresis por ser de un receptor de donante vivo y recibir una hidratacion de 80 mL.kg-1 de solucion fisiologica a 0,9%.BACKGROUND AND OBJECTIVES The success of renal transplantation (Tx) depends on the type of donor, length of cold ischemia, and hemodynamic parameters on reperfusion. The objective of this study was to analyze the anesthetic technique, the incidence of cardiovascular changes, and the presence of postoperative diuresis of Tx performed at UNICAMP. METHODS Renal transplantation of adults performed from January 2005 and April 2006 were evaluated retrospectively. Demographic data, preoperative laboratorial exams, anesthetic techniques and agents, hydration, hemodynamic parameters, use of vasoactive amines, presence of a diuresis, and intraoperative complications were evaluated, and comparative analysis between the subgroups, formed according to the anesthetic technique, was undertaken. The Student t test (parametric), Mann-Whitney test (non-parametric), Chi-square test and Fisher Exact test for comparison of proportions and multivariate analysis were used. RESULTS Ninety-two patients were evaluated; 59 underwent general anesthesia (GA) and 33 underwent general anesthesia associated with epidural block (GA + Epi); 42 patients received live-donor transplants and 50 from dead donors. Most preoperative parameters analyzed did not show statistically significant differences (p > 0.05), except for the origin of the graft (82% of GA + Epi received dead donor kidneys). Hypotension (30% GA and 48% GA + Epi, p < 0.05) was the most frequent cardiovascular change. The hydration regimen did not differ between both groups (86.7+/- 30.2 mL.kg(-1) GA and 94.8 +/- 21.8 mL.kg(-1) GA+Epi, p = 0.38). Dead donor grafts were more commonly associated with hemodynamic instability and worse prognosis for the immediate function of the graft, p < 0.01 and 0.01, respectively. Hydration of 80 mL.kg(-1) was associated with the presence of diuresis (OR = 2.94, CI 95% 1.00-8.32). CONCLUSIONS General anesthesia associated or not with epidural block was the anesthetic technique used. Hypotension was the most common hemodynamic change. Live-donor graft and volume of hydration of 80 mL.kg(-1) of NS favored diuresis.

Influence of the anesthetic technique on the hemodynamic changes in renal transplantation: a retrospective study

JUSTIFICATIVA Y OBJETIVOS: El exito en el transplante renal (Tx) depende del tipo de donador, de la duracion de la isquemia fria y de los parametros hemodinamicos en la reperfusion. El objetivo de esta investigacion fue analizar la tecnica anestesica, la incidencia de alteraciones cardiovasculares y el aparecimiento de diuresis en el periodo perioperatorio de los Tx realizados en la UNICAMP. METODO: Se evaluo retrospectivamente Tx de adultos realizados entre enero de 2005 y abril de 2006. Se tuvieron en cuenta los datos demograficos, los examenes laboratoriales preoperatorios, tecnicas y agentes anestesicos, hidratacion, parametros hemodinamicos, el uso de aminas vasoactivas, la presencia de diuresis y complicaciones intraoperatorias, con analisis comparativo entre los subgrupos formados conforme a la tecnica anestesica empleada. Se usaron en el analisis estadistico el test t de Student (parametricos), Mann-Whitney (no parametricos), test del Cui-cuadrado y Exacto de Fisher para la comparacion de proporciones y analisis multivariada. RESULTADOS: Se estudiaron 92 pacientes, 59 con anestesia general (AG) y 33 anestesia general asociada a la epidural (AG + Peri), 42 recibieron rinones de donantes vivos y 50 de fallecidos. No hubo diferencia (p < 0,05) en la mayoria de los parametros preoperatorios estudiados, con excepcion del origen del injerto (82% AG + Peri recibieron rinones de donante fallecido). La alteracion cardiovascular mas frecuente fue la hipotension arterial (30% AG y 48% AG + Peri, p < 0,05). El regimen de hidratacion no fue diferente entre los grupos (86,7 ± 30,2 mL.kg-1 AG y 94,8 ± 21,8 mL.kg-1 AG+Peri, p = 0,38). El injerto del donante fallecido se correlaciono con una mayor inestabilidad hemodinamica y con un peor pronostico para la funcion inmediata del injerto, p < 0,01 y 0,01 respectivamente. Un volumen de hidratacion de 80 mL.kg-1 se asocio a la diuresis (OR = 2,94, IC95% 1,00-8,32). CONCLUSIONES: La tecnica anestesica empleada fue anestesia general, asociada o no a la epidural. La alteracion hemodinamica mas comun fue la hipotension arterial. Se mostraron beneficos con relacion a la diuresis por ser de un receptor de donante vivo y recibir una hidratacion de 80 mL.kg-1 de solucion fisiologica a 0,9%.BACKGROUND AND OBJECTIVES The success of renal transplantation (Tx) depends on the type of donor, length of cold ischemia, and hemodynamic parameters on reperfusion. The objective of this study was to analyze the anesthetic technique, the incidence of cardiovascular changes, and the presence of postoperative diuresis of Tx performed at UNICAMP. METHODS Renal transplantation of adults performed from January 2005 and April 2006 were evaluated retrospectively. Demographic data, preoperative laboratorial exams, anesthetic techniques and agents, hydration, hemodynamic parameters, use of vasoactive amines, presence of a diuresis, and intraoperative complications were evaluated, and comparative analysis between the subgroups, formed according to the anesthetic technique, was undertaken. The Student t test (parametric), Mann-Whitney test (non-parametric), Chi-square test and Fisher Exact test for comparison of proportions and multivariate analysis were used. RESULTS Ninety-two patients were evaluated; 59 underwent general anesthesia (GA) and 33 underwent general anesthesia associated with epidural block (GA + Epi); 42 patients received live-donor transplants and 50 from dead donors. Most preoperative parameters analyzed did not show statistically significant differences (p > 0.05), except for the origin of the graft (82% of GA + Epi received dead donor kidneys). Hypotension (30% GA and 48% GA + Epi, p < 0.05) was the most frequent cardiovascular change. The hydration regimen did not differ between both groups (86.7+/- 30.2 mL.kg(-1) GA and 94.8 +/- 21.8 mL.kg(-1) GA+Epi, p = 0.38). Dead donor grafts were more commonly associated with hemodynamic instability and worse prognosis for the immediate function of the graft, p < 0.01 and 0.01, respectively. Hydration of 80 mL.kg(-1) was associated with the presence of diuresis (OR = 2.94, CI 95% 1.00-8.32). CONCLUSIONS General anesthesia associated or not with epidural block was the anesthetic technique used. Hypotension was the most common hemodynamic change. Live-donor graft and volume of hydration of 80 mL.kg(-1) of NS favored diuresis.

Bioética: aspectos de interesse do anestesiologista

BACKGROUND AND OBJECTIVES Medical evolution requires from health professionals the exercise of ethical reflections faced to daily situations, to avoid transgressing moral, ethical and legal rules. This article aimed at addressing bioethics principles to be observed during the Anesthesiology practice. CONTENTS After bioethics historical introduction and definition as a philosophic science, its interface with Law is demonstrated. Beneficence, non-malfeasance, respect to autonomy and justice principles are presented as critical points for the anesthetic practice, the primary objective of which is to preserve human dignity. The adherence to these principles protects patients against unexpected and undesirable results, in addition to protecting the anesthesiologist against ethical or legal implications after fortuitous complications. CONCLUSIONS Bioethics is integral part of health discussions; the progress of Anesthesiology and research requires the understanding of this subject to adequately practice the specialty. Although being philosophical, and to a certain extent apart from a specialty focused on acute attention to patients, anesthesiologists are willing to understand this new science, which will increasingly influence the practice of the specialty, in order to protect patients and avoid further inconveniences in the rather difficult practice of this specialty in our country.JUSTIFICATIVA E OBJETIVOS: La evolucion de la Medicina exige de los profesionales de la salud la realizacion de una serie de reflexiones de sello etico, frente a las situaciones enfrentadas diariamente, de manera a no transgredir reglas morales, eticas y legales. El objetivo de este articulo fue el de abordar los principios de la bioetica que deben ser observados durante el ejercicio de la Anestesiologia. CONTENIDO: Despues de la introduccion historica y la definicion de bioetica como una ciencia de sello filosofico, se demuestran sus interconexiones con el Derecho. Los principios de la beneficencia, de la no maldad, del respeto a la autonomia y a la justicia se presentan como puntos esenciales de la practica de la Anestesiologia, cuyo objetivo es, primordialmente, la preservacion de la dignidad del ser humano. La observacion de esos principios protege al paciente de resultados inesperados, indeseables y tambien al anestesiologo de implicaciones en la esfera etica o juridica frente a complicaciones fortuitas. CONCLUSIONES: La bioetica se hizo inseparable en el ambito de las discusiones de la salud; para el progreso de la Anestesiologia y de la investigacion hacen necesarios conocimientos de esa area en la practica de la especialidad. Aunque de sello filosofico, de una cierta manera un poco lejos de la especialidad que prima por una atencion aguda al paciente, los anestesiologos tienen todo el interes en conocer esa nueva ciencia que cada dia mas, seguramente, influira en la practica de la especialidad, para proteger sus pacientes y evitar mas trastornos en la practica de una especialidad ya bastante dificil en el pais.

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.

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.

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.