Glória Maria Braga Potério

The Effect of Walking With High-Heeled Shoes on the Leg Venous Pressure

It is common belief that the use of high-heeled shoes is deleterious to venous return, by impairing the efficiency of the muscular calf pump. Ambulatory venous pressure obtained with dorsal foot venipuncture is the gold standard in the evaluation of venous pressure during walking, but it is not routinely used in clinical practice. The objective of the present study was to determine the variations in leg venous pressure obtained with a new noninvasive method, in individuals without venous disease, walking without shoes and wearing high-heeled shoes. A new method of evaluation of the venous pressure by means of air plethysmography was applied to 10 volunteers (20 limbs). The patients were evaluated while standing, with ortho-static flexion and extension foot movements, and while walking on a treadmill barefooted and wearing high-heeled shoes. It was found that the variation on the cuff pressure during walking with high-heeled shoes was higher than the variation on the cuff pressure walking barefooted (52.2 ±8.89 x 26.65 ±6.7 mm Hg, p<0.0001), and the final hydrostatic venous pressure was lower (51.5 ±12.78 x 61.5 ±8.44 mm Hg). The use of high-heeled shoes increases muscular effort during walking and diminishes the leg venous pressure compared with barefooted.

Spinal anesthesia for cesarean section. Use of hyperbaric bupivacaine (10mg) combined with different adjuvants.

BACKGROUND AND OBJECTIVES Combination of local anesthetics (LA) with adjuvants for spinal anesthesia improves block quality and prolongs the duration of analgesia. It was evaluated the maternal effects and neonatal repercussions of sufentanil, morphine, and clonidine combined with hyperbaric bupivacaine for elective cesarean section. METHOD Prospective, randomized, blinded study of 96 patients allocated into four groups: Group I (no adjuvant), Group II (sufentanil 5.0 μg), Group III (morphine 100 μg), and Group IV (clonidine 75 μg). It was evaluated the onset and level of sensory block, perioperative analgesia, degree and recovery time of motor block, duration of analgesia, sedation, and maternal-fetal repercussions. RESULTS The onset of blockade was significantly faster in groups with adjuvants compared with Group I. Patients in Groups I and III reported pain during the perioperative period. Duration of analgesia was significantly higher in Group II and time to motor block recovery was significantly higher in Group IV. Pruritus occurred in Groups II and III. Sedation was significant in Group IV and there was prolonged arterial hypotension in Group IV. CONCLUSION Addition of sufentanil and clonidine to hyperbaric bupivacaine provided adequate anesthesia for cesarean section and good postoperative analgesia. Clonidine caused more perioperative sedation and longer time to motor block recovery. Pruritus was evident when opioids were used.

Influence of Local Anesthetics on the Neuromuscular Blockade Produced by Rocuronium. Effects of Lidocaine and 50% Enantiomeric Excess Bupivacaine on the Neuromuscular Junction

BACKGROUND AND OBJECTIVES The effects of local anesthetics (LA) on neuromuscular transmission and their influence on the neuromuscular blockade produced by competitive neuromuscular blockers have not been fully investigated. The objective of this study was to evaluate, in vitro, the effects of lidocaine and 50% enantiomeric excess bupivacaine (S75-R25) on the neuromuscular blockade produced by rocuronium. METHODS The rats were divided in five groups (n = 5) according to the drug used: isolated lidocaine, bupivacaine (S75-R25), or rocuronium (groups I, II, and II); and rocuronium in preparations previously exposed to LAs (groups IV and V). The concentrations used were as follows: 20 microg x mL(-1), 5 microg x mL(-1), and 4 microg x mL(-1) of lidocaine, bupivacaine (S75-R25), and rocuronium, respectively. The following parameters were evaluated: 1) the strength of muscular contraction of the diaphragm to indirect electrical stimulations, before and 60 minutes after the isolated addition of the LAs and rocuronium, and the association AL-rocuronium; and 2) the effects of LAs on membrane potential (MP) and miniature end-plate potentials (MEPP). The effect of LAs on muscle contraction in response to acetylcholine was evaluated in chick biventer cervicis preparations. RESULTS Isolated lidocaine and bupivacaine (S75-R25) did not change the muscular response and the levels of MPs. In preparations exposed to LAs, rocuroniuminduced blockade was significantly greater than that produced by rocuronium alone. In chick biventer cervicis preparations, lidocaine and bupivacaine (S75R25) decreased contraction in response to acetylcholine. Lidocaine increased the frequency of MEPPs, which was followed by the blockade; bupivacaine (S75R25) caused a reduction in MEPPs followed by blockade. CONCLUSIONS Local anesthetics caused a potentiation of the neuromuscular blockade produced by rocuronium. The results showed pre- and post-synaptic effects.

Influência de anestésicos locais sobre o bloqueio neuromuscular produzido pelo rocurônio: ação da lidocaína e da mistura enantiomérica em excesso de 50% de bupivacaína na junção neuromuscular

JUSTIFICATIVA Y OBJETIVOS: Los efectos de los anestesicos locales (AL), en la transmision neuromuscular y su influencia en el bloqueo neuromuscular producido por bloqueadores neuromusculares competitivos, todavia no se ha investigado lo suficiente. El objetivo del estudio, fue evaluar in vitro los efectos de la lidocaina y de la mezcla enantiomerica en exceso de 50% de bupivacaina (S75-R25) en el bloqueo neuromuscular producido por el rocuronio. METODOS: Algunos ratones se distribuyeron en cinco grupos (n = 5) de acuerdo con el farmaco estudiado: lidocaina, bupivacaina (S75-R25), rocuronio, aisladamente (Grupos I, II, III); rocuronio en preparaciones previamente expuestas a los AL (Grupos IV, V). Las concentraciones utilizadas fueron: 20 µg.mL-1, 5 µg.mL-1 y 4 µg.mL-1, para lidocaina, bupivacaina (S75-R25), y rocuronio, respectivamente. Se evaluo: 1) la fuerza de contraccion muscular del diafragma a la estimulacion electrica indirecta, antes y 60 minutos despues de la adicion de los AL y rocuronio aisladamente, y la asociacion AL - rocuronio; 2) efectos de los AL sobre el potencial de la membrana (PM) y potenciales de placa terminal en miniatura (PPTM). En una preparacion biventer cervicis de pollito, se evaluo el efecto de los AL en la respuesta de contraccion a la acetilcolina. RESULTADOS: La lidocaina y la bupivacaina (S75-R25) aisladamente, no alteraron las respuestas musculares y los valores del PM. En las preparaciones expuestas a los AL, el bloqueo por el rocuronio fue significativamente mayor con relacion al producido por el rocuronio aisladamente. En una preparacion biventer cervicis de pollito, la lidocaina y la bupivacaina (S75-R25), redujeron la respuesta de contraccion a la acetilcolina. La lidocaina aumento la frecuencia de los PPTM, seguido de bloqueo; la bupivacaina (S75-R25) genero una disminucion seguida de bloqueo. CONCLUSIONES: Los anestesicos locales potenciaron el bloqueo neuromuscular causado por el rocuronio. Los resultados mostraron una accion presinaptica y postsinaptica.

Influence of stimulus frequency on blockade induced by pancuronium and rocuronium: study on rats phrenic nerve-diaphragm preparation

PURPOSE To evaluate the influence of two stimulation frequencies on the installation of neuromuscular blockade produced by pancuronium and rocuronium on the rat diaphragm. METHODS Diaphragms were submitted to an indirect frequency stimulation of 0.1 and 1 Hz (Groups I and II, respectively). Subgroups were formed (n=5) according to the neuromuscular blocker employed (pancuronium-2 microg/ml and rocuronium-4 microg/ml). The twitch height depression was evaluated at 5, 15 and 30 minutes after adding the neuromuscular blocker. RESULTS The decrease in twitch height was greater (p<0.01) with a frequency of 1 Hz at all time periods studied both in preparations that are blocked with pancuronium and in those that are blocked with rocuronium. CONCLUSION The frequency of stimulation interferes significantly with the installation of neuromuscular blockade produced by pancuronium and rocuronium, since the reduction in amplitude of the rat diaphragm response was greater for 1 Hz frequencies, at all periods studied.

Influence of lidocaine on the neuromuscular block produced by rocuronium: study in rat phrenic-diaphragmatic nerve preparation

BACKGROUND AND OBJECTIVES: The action mechanism of local anesthetics (LA) on neuromuscular junction motivated several studies. When administered at low doses, they do not interfere on neuromuscular transmission. But high doses may compromise neuromuscular transmission and increase the effects of neuromuscular blockers. The objective of this study was to evaluate lidocaine interaction with rocuronium on rat diaphragm through its influence on neuromuscular block degree. METHODS: Rats, weighing between 250 and 300 g, were used. Preparation was set according to the technique described by Bulbring. Groups were formed (n = 5) according to the drug being studied: lidocaine - 20 µg.mL-1 (Group I); rocuronium - 4 µg.mL-1 (Group II), and rocuronium - 4 µg.mL-1 with lidocaine - 20 µg.mL-1 (Group III). The following items were assessed: 1) the extent of diaphragm muscle responses to indirect stimulation, both before and 60 minutes after adding lidocaine and a neuromuscular blocker; 2) membrane potentials (MP) and miniature end-plate potentials (MEPP); 3) the effectiveness of neostigmine, and 4) aminopyridine on neuromuscular blockage reversal. RESULTS: When administered separately, lidocaine did not alter the extent of muscular responses. With the previous use of lidocaine, rocuronium neuromuscular blockage was 82.8% ± 1.91%, with a significant difference (p = 0.0079) when compared to the group with isolated rocuronium (57.8% ± 1.9%). Blockage was both partially and fully reverted by neostigmine and 4-aminopyridine, respectively. Lidocaine did not alter membrane potential and caused an initial increase on MEPP, followed by a blockage. CONCLUSIONS: Lidocaine increases the neuromuscular blocking produced by rocuronium. MEPP modifications identify a presynaptic action. The complete antagonism of 4-aminopyridine indicates a presynaptic component. This idea is supported by the partial antagonism through neostigmine.BACKGROUND AND OBJECTIVES The action mechanism of local anesthetics (LA) on neuromuscular junction motivated several studies. When administered at low doses, they do not interfere on neuromuscular transmission. But high doses may compromise neuromuscular transmission and increase the effects of neuromuscular blockers. The objective of this study was to evaluate lidocaine interaction with rocuronium on rat diaphragm through its influence on neuromuscular block degree. METHODS Rats, weighing between 250 and 300 g, were used. Preparation was set according to the technique described by Bulbring. Groups were formed (n = 5) according to the drug being studied: lidocaine - 20 microg.mL-1 (Group I); rocuronium - 4 microg.mL-1 (Group II), and rocuronium - 4 microg.mL-1 with lidocaine - 20 microg.mL-1 (Group III). The following items were assessed: 1) the extent of diaphragm muscle responses to indirect stimulation, both before and 60 minutes after adding lidocaine and a neuromuscular blocker; 2) membrane potentials (MP) and miniature end-plate potentials (MEPP); 3) the effectiveness of neostigmine, and 4) aminopyridine on neuromuscular blockage reversal. RESULTS When administered separately, lidocaine did not alter the extent of muscular responses. With the previous use of lidocaine, rocuronium neuromuscular blockage was 82.8% +/- 1.91%, with a significant difference (p = 0.0079) when compared to the group with isolated rocuronium (57.8% +/- 1.9%). Blockage was both partially and fully reverted by neostigmine and 4-aminopyridine, respectively. Lidocaine did not alter membrane potential and caused an initial increase on MEPP, followed by a blockage. CONCLUSIONS Lidocaine increases the neuromuscular blocking produced by rocuronium. MEPP modifications identify a presynaptic action. The complete antagonism of 4-aminopyridine indicates a presynaptic component. This idea is supported by the partial antagonism through neostigmine.

Anaphylaxis during renal transplantation of live donor graft in a child with latex allergy: case report

BACKGROUND AND OBJECTIVES Latex allergy is becoming increasingly more frequent, affecting patients and health care professionals. The objective of this report was to present the case of a child with allergy to latex, who developed anaphylaxis during anesthesia for renal transplantation, and emphasize some of the multidisciplinary conducts used to decrease the risk of anaphylactic shock after graft reperfusion. CASE REPORT A male child, 5 years and 10 months old, P3 by the ASA classification, with a history of allergy to latex diagnosed after contact with balloons and confirmed by Rast test specific for latex and Prick test, underwent renal transplantation of a live donor graft for end-stage renal disease secondary to urologic malformation. The protocols for patients with Latex Allergy adopted by the Anesthesiology and Nursing Departments of the Hospital das Clínicas da UNICAMP were observed to avoid exposure of the child to latex. They started the day before the surgery by cleaning the operating rooms and substituting of all medical-hospital products by latex-free material. The equipment and materials used during the procedure were latex-free according to a technical report provided by the manufacturers. The surgery was done under general anesthesia and controlled mechanical ventilation. At the end of the surgery, the patient required blood transfusion, which was administered by a pressurizer; he developed cutaneous rash and the blood transfusion was discontinued, hydrocortisone was administered, and the infusion of crystalloids was increased. The child had an immediate and satisfactory response to the treatment. CONCLUSIONS Latex allergy has become a public health problem and the knowledge of specific therapeutic conducts allows immediate treatment and decreases patient risks.JUSTIFICATIVA E OBJETIVOS: A alergia ao latex vem se tornando frequente, atingindo pacientes e profissionais de saude. O objetivo deste relato foi apresentar um caso de crianca alergica ao latex que desenvolveu crise anafilatica durante anestesia para transplante renal e destacar algumas condutas multiprofissionais empregadas para diminuir o risco de choque anafilatico apos a reperfusao do transplante. RELATO DO CASO: Crianca do sexo masculino, com 5 anos e 10 meses, P3 pela classificacao da ASA, com historia de alergia ao latex, diagnosticada apos contato com bexigas de festa e confirmada por testes Rast especifico para o latex e Prick teste, foi submetida a transplante renal intervivos, por insuficiencia renal terminal em consequencia de malformacao urologica. Os cuidados para evitar a exposicao da crianca ao latex seguiram os protocolos para paciente alergico ao latex, adotados pelo Servico de Anestesia e de Enfermagem do Hospital das Clinicas da UNICAMP. Foram iniciados na vespera da operacao com a limpeza terminal das salas cirurgicas e a substituicao de todos os produtos medico-hospitalares por produtos isentos de latex. Os equipamentos e materiais utilizados durante o procedimento possuiam laudo tecnico de isencao completa de latex, fornecido pelo fabricante. A operacao foi realizada sob anestesia geral com ventilacao controlada mecânica. Ao final da operacao necessitou de transfusao de concentrado de hemacias administrado com auxilio de pressurizador, apresentando rash cutâneo, cessou-se a transfusao, administrou-se hidrocortisona e aumentou-se a infusao de cristaloides. A resposta ao tratamento foi satisfatoria e imediata. CONCLUSOES: A alergia ao latex tornou-se um problema de saude publica e o conhecimento de condutas terapeuticas especificas possibilita o pronto atendimento e menor risco para os pacientes

Proporção entre os segmentos do anel da valva tricúspide normal: um parâmetro para realização da anuloplastia valvar

Objective: The purpose of this study was to determine the proportions among the segments of the human tricuspid valve annulus. Methods: A descriptive autopsy study was made of 30 human hearts without fixation, within six hours of death, without congenital or acquired lesions and without tricuspid regurgitation. Tricuspid valve insufficiency was excluded by the infusion of pressurized water in the right ventricle with the pulmonary valve closed. Digital images of the tricuspid ring in its anatomical position and after flattening were analyzed by specific software. The mean measurements and ratios were compared in the two different situations. Results: The mean measurements of the perimeter, septal and antero-posterior segments of the tricuspid ring in the anatomical position were: 105 mm (± 12.7), 30.6 mm (± 3.7) and 74 mm (± 9.4), respectively. When flattened, the mean measurement of the perimeter was 117.5 mm (± 13.3) and the sizes of the septal, anterior and posterior segments were 32 mm (± 3.7), 46.3 mm (± 8.3) and 39.1 mm (± 8.5), respectively. The mean ratio between the antero-posterior and septal segments was 2.43 (± 0.212) in the anatomical position and when flattened it was 2.67 (± 0.304). Statistical differences were observed in the measurements of the perimeter (p<0.0001), septal segment (p=0.003) and antero-posterior segment (p<0.0001) in both situations. Statistical differences also occurred in the ratios between the antero-posterior and septal segments (p=0.0005). Conclusions: The proportion between the septal and antero-posterior segments of the normal human tricuspid valve is 1:2.43. Flattening the tricuspid ring to measure the segments, changes the values and the ratios between them.

Reação anafilática durante transplante renal intervivos em criança alérgica ao látex: relato de caso

BACKGROUND AND OBJECTIVES Latex allergy is becoming increasingly more frequent, affecting patients and health care professionals. The objective of this report was to present the case of a child with allergy to latex, who developed anaphylaxis during anesthesia for renal transplantation, and emphasize some of the multidisciplinary conducts used to decrease the risk of anaphylactic shock after graft reperfusion. CASE REPORT A male child, 5 years and 10 months old, P3 by the ASA classification, with a history of allergy to latex diagnosed after contact with balloons and confirmed by Rast test specific for latex and Prick test, underwent renal transplantation of a live donor graft for end-stage renal disease secondary to urologic malformation. The protocols for patients with Latex Allergy adopted by the Anesthesiology and Nursing Departments of the Hospital das Clínicas da UNICAMP were observed to avoid exposure of the child to latex. They started the day before the surgery by cleaning the operating rooms and substituting of all medical-hospital products by latex-free material. The equipment and materials used during the procedure were latex-free according to a technical report provided by the manufacturers. The surgery was done under general anesthesia and controlled mechanical ventilation. At the end of the surgery, the patient required blood transfusion, which was administered by a pressurizer; he developed cutaneous rash and the blood transfusion was discontinued, hydrocortisone was administered, and the infusion of crystalloids was increased. The child had an immediate and satisfactory response to the treatment. CONCLUSIONS Latex allergy has become a public health problem and the knowledge of specific therapeutic conducts allows immediate treatment and decreases patient risks.JUSTIFICATIVA E OBJETIVOS: A alergia ao latex vem se tornando frequente, atingindo pacientes e profissionais de saude. O objetivo deste relato foi apresentar um caso de crianca alergica ao latex que desenvolveu crise anafilatica durante anestesia para transplante renal e destacar algumas condutas multiprofissionais empregadas para diminuir o risco de choque anafilatico apos a reperfusao do transplante. RELATO DO CASO: Crianca do sexo masculino, com 5 anos e 10 meses, P3 pela classificacao da ASA, com historia de alergia ao latex, diagnosticada apos contato com bexigas de festa e confirmada por testes Rast especifico para o latex e Prick teste, foi submetida a transplante renal intervivos, por insuficiencia renal terminal em consequencia de malformacao urologica. Os cuidados para evitar a exposicao da crianca ao latex seguiram os protocolos para paciente alergico ao latex, adotados pelo Servico de Anestesia e de Enfermagem do Hospital das Clinicas da UNICAMP. Foram iniciados na vespera da operacao com a limpeza terminal das salas cirurgicas e a substituicao de todos os produtos medico-hospitalares por produtos isentos de latex. Os equipamentos e materiais utilizados durante o procedimento possuiam laudo tecnico de isencao completa de latex, fornecido pelo fabricante. A operacao foi realizada sob anestesia geral com ventilacao controlada mecânica. Ao final da operacao necessitou de transfusao de concentrado de hemacias administrado com auxilio de pressurizador, apresentando rash cutâneo, cessou-se a transfusao, administrou-se hidrocortisona e aumentou-se a infusao de cristaloides. A resposta ao tratamento foi satisfatoria e imediata. CONCLUSOES: A alergia ao latex tornou-se um problema de saude publica e o conhecimento de condutas terapeuticas especificas possibilita o pronto atendimento e menor risco para os pacientes

In vitro and in vivo neuromuscular effects of atracurium and rocuronium in rats treated with carbamazepine for seven days

JUSTIFICATIVA Y OBJETIVOS: Se trata de un estudio experimental que investigo in vitro e in vivo el bloqueo neuromuscular producido por el rocuronio y atracurio en ratones tratados con carbamazepina y determino las concentraciones de citocromo P450 y b5 reductasis en microsomas hepaticos. METODO: Ratones fueron tratados por siete dias con carbamazepina (CBZ) - 40 mg.kg-1 a traves de una sonda y sacrificados al octavo dia bajo anestesia con uretana. Las preparaciones in vitro e in vivo fueron montadas de acuerdo con las tecnicas de Bulbring y de Leeuwin y Wolters, respectivamente. Las concentraciones y dosis utilizadas de los bloqueadores en las preparaciones in vitro e in vivo fueron, respectivamente, 20 µg.mL-1 y 0,5 mg.kg-1 para atracurio (ATC); 4 µg.mL-1 y 0,6 mg.kg-1 para rocuronio (ROC). Cada protocolo tuvo un n = 5 y las respuestas fueron observadas por 60 minutos. Los efectos del ATC y ROC fueron evaluados en las preparaciones de ratones tratados (Cbzt) y comparados a los observados en los de ratones no tratados (CBZst). Las concentraciones de citocromo P450 y b5 reductasis fueron determinadas en microsomas aislados de higados de ratones tratados (CBZt) y comparadas con las obtenidas en ratones no tratados (CBZst) RESULTADOS: La carbamazepina no altero la amplitud de las respuestas musculares; in vitro y in vivo, no hubo diferencia entre el bloqueo neuromuscular producido por el atracurio en las preparaciones CBZt versus CBZst; el bloqueo neuromuscular producido por el Rocuronio en las preparaciones CBZt fue potenciado in vitro. La carbamazepina no altero las concentraciones de citocromo P450 y b5. CONCLUSIONES: El tratamiento por siete dias con carbamazepina, no influencio en el bloqueo producido por el atracurio, y altero in vitro los efectos del rocuronio. El tiempo de tratamiento no fue suficiente para causar la induccion enzimatica y disminuir la sensibilidad al rocuronio.BACKGROUND AND OBJECTIVES This experimental study investigated the in vitro and in vivo neuromuscular blockade of rocuronium and atracurium in rats treated with carbamazepine and determined the concentration of cytochrome P450 and b5 reductase in hepatic microsomes. METHODS Rats were treated with carbamazepine (CBZ)--40 mg x kg(-1) by gavage and sacrificed on the eighth day under anesthesia with urethane. In vitro and in vivo preparations followed the techniques of Bulbring and Leeuwin and Wolters, respectively. Concentrations and doses of the neuromuscular blockers used in in vitro and in vivo preparations were, respectively, 20 microg x mL(-1) and 0.5 mg x kg(-1) for atracurium (ATC); and 4 microg x kg(-1) and 0.6 mg x kg(-1) for rocuronium (ROC). Each protocol had an n = 5 and the response was observed for 60 minutes. The effects of ATC and ROC were evaluated in the preparations of rats treated with carbamazepine (CBZ(t)) and compared to those of non-treated rats (CBZ(st)). The concentration of cytochrome P450 and b5 reductase were determined in hepatic chromosomes of rats treated with carbamazepine (CBZ(t)) and non-treated rats (CBZ(st)). RESULTS Carbamazepine did not change the amplitude of neuromuscular response; differences in the neuromuscular blockade produced by atracurium in CBZ1 preparations were not observed, in vitro or in vivo, when compared with CBZ(st); the neuromuscular blockade produced by rocuronium in CBZ(t) preparations was potentiated in vitro. Carbamazepine did not change the concentrations of cytochrome P450 and b5. CONCLUSIONS Seven-day treatment with carbamazepine did not change the neuromuscular blockade produce by atracurium, but altered the in vitro effects of rocuronium. The duration of the treatment was not enough to cause enzymatic induction and decrease the sensitivity to rocuronium.