RESUMEN
The authors describe a strangulated umbilical hernia surgery performed in emergency with a paraumbilical block associated with a local infiltration. For this patient, 3-4 ASA status, in occlusion, with iterative vomiting and coagulation disorders, general or spinal anaesthesia were high-risk technics. Paraumbilical block, sometimes used for anaesthesia or/and analgesia for programmed umbilical hernia surgery, allowed surgery with good conditions and procured prolonged postoperative analgesia. This block, easy to perform, is an interesting alternative in emergency for general or spinal anaesthesia in high-risk patients.
Asunto(s)
Hernia Umbilical/cirugía , Bloqueo Nervioso/métodos , Anciano , Servicio de Urgencia en Hospital , Humanos , Hipertensión Portal/complicaciones , Cirrosis Hepática Alcohólica/complicaciones , Masculino , Periodo Posoperatorio , Resultado del TratamientoRESUMEN
We report the case of a 52-year-old man, ASA 3-4, malnourished, heavy smoker and drinker at the stage of chronic obstructive pulmonary disease and cirrhosis. The postoperative course of a cervical cancer surgery was complicated by a pneumonia with fatal outcome in the intensive care unit. Taking into account the patient's history and surgical requirements, this nosocomial infection did not appear easily preventable. The multiple risk factors and the few preventive measures usable were analyzed. In this context, the media and legal trend to make the doctors responsible for the nosocomial infections should be revised.
Asunto(s)
Profilaxis Antibiótica , Infección Hospitalaria/etiología , Neumonía/etiología , Complicaciones Posoperatorias/etiología , Alcoholismo/complicaciones , Combinación Amoxicilina-Clavulanato de Potasio/administración & dosificación , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Ciprofloxacina/uso terapéutico , Infección Hospitalaria/prevención & control , Susceptibilidad a Enfermedades , Resultado Fatal , Humanos , Enfermedad Iatrogénica , Huésped Inmunocomprometido , Cirrosis Hepática Alcohólica/complicaciones , Masculino , Desnutrición/complicaciones , Mala Praxis/legislación & jurisprudencia , Persona de Mediana Edad , Boca/microbiología , Disección del Cuello , Recurrencia Local de Neoplasia/cirugía , Oxígeno/uso terapéutico , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/uso terapéutico , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam , Neumonía/prevención & control , Complicaciones Posoperatorias/prevención & control , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Factores de Riesgo , Fumar/efectos adversos , Neoplasias de la Lengua/radioterapia , Neoplasias de la Lengua/cirugíaAsunto(s)
Apendicectomía , Bloqueo Nervioso , Dolor Postoperatorio/terapia , Nervios Periféricos , Niño , Humanos , Plexo Hipogástrico , Ilion/inervación , MasculinoRESUMEN
Medial canthus episclera (sub-Tenon's) anaesthesia is a technique proposed as a suitable alternative to the more classical peribulbar block because of the greater reliability and more constancy in effectiveness. We report two cases of retrobulbar haematoma after sub-Tenon's anaesthesia, one with central retina artery compression needed anterior room punction. Sub-Tenon's anaesthesia, like peribulbar anaesthesia, can give also retrobulbar haemorrhage if the insertion of the needle is not limited to the anterior orbit.
Asunto(s)
Hemorragia del Ojo/etiología , Bloqueo Nervioso/efectos adversos , Órbita , Anciano , Anciano de 80 o más Años , Extracción de Catarata , Femenino , Humanos , Procedimientos Quirúrgicos Oftalmológicos , Arteria Retiniana/patología , Arteria Retiniana/cirugía , Enfermedades de la Retina/cirugía , Hemorragia Retrobulbar/inducido químicamenteRESUMEN
Possible mechanisms of the ability of clonidine to correct bupivacaine-induced ventricular electrophysiologic impairment were evaluated in an electrophysiologic model on closed-chest dogs. Nine groups (n = 6) of pentobarbital-anesthetized dogs were given atropine, 0.2 mg/kg intravenously (i.v.), and bupivacaine, 4 mg/kg i.v., over a 10-s period. Group 1 was then given only saline solution. Group 2 was given clonidine, 0.01 mg/kg i.v., over a 1-min period. Group 3 was given clonidine followed by i.v. administration of yohimbine, 1 mg/kg, an alpha 2-antagonist. Group 4 was given carbachol, 1 mg/kg i.v., a long-lasting cholinergic agonist, over a 1-min period. Group 5 was given electrical stimulation of the left vagus nerve. Group 6 was given physostigmine, 0.1 mg/kg i.v., known to inhibit cholinesterase degradation, 5 min before bupivacaine administration, and Group 7 received a combination of physostigmine pretreatment and electrical vagal stimulation. Group 8 was given physostigmine, 0.1 mg/kg i.v., and pancuronium bromide, 1 mg/kg i.v., known to inhibit nicotinic receptors, 5 min before bupivacaine administration. Then electrical stimulation of the left vagus nerve was performed. Group 9 was given nicotine, 0.1 mg/kg i.v., 1 min after bupivacaine injection over 1 min. Bupivacaine induced bradycardia, markedly increased the His-Purkinje conduction time (HV interval) and QRS duration. Bupivacaine decreased the peak of first derivative of left ventricle pressure (LVdP/dtmax) and increased left ventricular end-diastolic pressure (LVEDP). Clonidine improved QRS duration and HV interval. Yohimbine did not modify the effects of clonidine. QRS duration and HV interval were significantly improved in Groups 4-7. In Group 8, pancuronium pretreatment inhibited the beneficial effects of the combination of physostigmine pretreatment and electrical vagal stimulation. In contrast, in Group 9, like clonidine, nicotine improved QRS duration and HV interval. Three other groups of anesthetized dogs (n = 6) were then studied. All dogs were given hexamethonium, 10 mg/kg i.v. Then, Group 10 was given only saline solution; Group 11 was given bupivacaine, 4 mg/kg, and Group 12 was given bupivacaine and nicotine as in Group 9. In Group 11, bupivacaine induced its usual alterations. In contrast, nicotine did not modify the cardiotoxic profile of bupivacaine after hexamethonium pretreatment. We conclude that the beneficial effect of clonidine on the variables of ventricular conduction altered by bupivacaine 1) is not mediated by central alpha 2-activation, 2) is mediated by the activation of parasympathetic pathways, and 3) is indirect and not mediated by acetylcholine release but is mediated by the activation of parasympathetic ganglionic nicotinic receptors.(ABSTRACT TRUNCATED AT 400 WORDS)
Asunto(s)
Bupivacaína/antagonistas & inhibidores , Clonidina/uso terapéutico , Sistema de Conducción Cardíaco/efectos de los fármacos , Receptores Nicotínicos/fisiología , Animales , Bupivacaína/toxicidad , Carbacol/farmacología , Clonidina/farmacología , Perros , Electrofisiología , Femenino , Bloqueadores Ganglionares/farmacología , Hemodinámica/fisiología , Hexametonio , Compuestos de Hexametonio/farmacología , Masculino , Nicotina/farmacología , Pancuronio/farmacología , Fisostigmina/farmacología , Yohimbina/farmacologíaRESUMEN
BACKGROUND: Some reports suggest that activation of the autonomic nervous system by bupivacaine could participate in its cardiotoxicity. This is based in part on the fact that hexamethonium suppresses cardiac disturbances in anesthetized rabbits given small intracerebroventricular doses of bupivacaine. The aims of the current study were to determine, in anesthetized dogs, (1) whether the activation of the autonomic nervous system is deleterious after a large intravenous dose of bupivacaine and (2) whether the parasympathetic or sympathetic system is implicated in the bupivacaine-induced deleterious activation of the autonomic nervous system. METHODS: We used an electrophysiologic model in closed-chest dogs anesthetized with sodium pentobarbital. In group 1 (n = 6), dogs were given 4 mg/kg intravenous bupivacaine over 10 s. In group 2 (n = 6), dogs were given the same dose of bupivacaine 5 min after having received 0.2 mg/kg intravenous atropine sulfate. In group 3 (n = 9), dogs were pretreated with 10 mg/kg intravenous hexamethonium and then given bupivacaine 4 mg/kg. In addition, in group 3, the right atrium was paced at a basic cycle length of 400 ms to obtain a heart rate similar to that of group 1. RESULTS: Bupivacaine in group 1 induced significant bradycardia; lengthening of PR, atria-His, His-ventricle, and QTc intervals; and QRS widening. The first derivative of left ventricular pressure was significantly decreased, whereas left ventricular end-diastolic pressure was increased. Atropine pretreatment did not modify cardiac disturbances induced by bupivacaine. Hexamethonium pretreatment induced significantly less QRS widening and QTc lengthening than was seen in group 1 but worsened the bupivacaine effects on bradycardia, atria-His and PR intervals, mean aortic pressure, and first derivative of left ventricular pressure. Moreover, atrial pacing in group 3 induced alterations of QRS similar to those in group 1. CONCLUSIONS: Considering that marked slowing of ventricular conduction velocity (i.e., QRS widening) is known to facilitate reentrant ventricular arrhythmias, we conclude that (1) the activation of the autonomic nervous system by bupivacaine is not as deleterious as previously suggested; (2) the parasympathetic system is not markedly implicated in the worsening of direct bupivacaine cardiotoxicity; and (3) the sympathetic nervous system acts only by inducing a less marked bradycardia, which slows ventricular conduction velocity in a use-dependent manner, facilitating reentrant arrhythmias.
Asunto(s)
Antihipertensivos/uso terapéutico , Bupivacaína/toxicidad , Cardiopatías/inducido químicamente , Cardiopatías/prevención & control , Compuestos de Hexametonio/uso terapéutico , Anestesia , Animales , Función Atrial , Atropina/farmacología , Bupivacaína/sangre , Estimulación Cardíaca Artificial , Perros , Relación Dosis-Respuesta a Droga , Electrocardiografía/efectos de los fármacos , Electrofisiología , Femenino , Corazón/efectos de los fármacos , Corazón/fisiología , Atrios Cardíacos/efectos de los fármacos , Sistema de Conducción Cardíaco/efectos de los fármacos , Sistema de Conducción Cardíaco/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Hexametonio , Masculino , Modelos Biológicos , Sistema Nervioso Parasimpático/efectos de los fármacos , Sistema Nervioso Parasimpático/fisiología , Pentobarbital , Canales de Sodio/efectos de los fármacosRESUMEN
Sciatic nerve blocks were seldom used until recently. They apply to most surgical procedures on the lower limb and are often combined with a "3 in 1" block. However they can be used alone for foot surgery or postoperative analgesia. Nerve stimulators make their realization easier and more reliable. Sciatic nerve block can be obtained by different techniques. The choice of which being helped by some guidelines according to the patients characteristics and the surgical site.
Asunto(s)
Bloqueo Nervioso/métodos , Nervio Ciático , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , HumanosRESUMEN
Although potassium channel openers have been demonstrated to induce arterial vasodilation and shortening of the QT interval, the complete in vivo hemodynamic and electrophysiologic profile of these drugs has not been fully established. We evaluated the effects of BRL 38227, the active enantiomer of cromakalim, on the electrophysiologic and hemodynamic parameters in anesthetized dogs. Four intravenous (i.v.) doses (0.01, 0.03, 0.1, and 0.3 mg/kg) of BRL 38227 (lemakalim) were given to four different groups of 6 anesthetized and mechanically ventilated dogs. Electrophysiologic and hemodynamic parameters were measured with bipolar catheters positioned in the right atria and the right ventricle and double micromanometers placed in the left ventricle and the aorta. Nine dogs died of ventricular fibrillation (VF; 6 of 6 after 0.3 mg/kg, 2 of 8 dogs after 0.1 mg/kg, and 1 of 7 dogs after 0.03 mg/kg BRL 38227). Three dogs had atrial tachycardia (1 had atrial flutter and 1 had atrial fibrillation after 0.03 mg/kg, and 1 had atrial fibrillation after 0.01 mg/kg BRL 38227). BRL 38227 did not modify heart rate (HR), corrected sinus recovery time (CSRT), and atrial or atrio-ventricular (A-V) conduction times. In contrast, PR interval, Luciani-Wenckebach cycle length (LW), HV interval, QRS duration, ventricular effective refractory period (VERP), QT interval, and monophasic action potential (AP) were significantly shortened in a dose-dependent manner. Left ventricular end-diastolic pressure (LVEDP) was not modified, whereas LVdP/dtmax decreased significantly at 0.1 mg/kg BRL 38227. Finally, there was a significant dose-dependent decrease in systolic, diastolic, and mean aortic blood pressure (SBP, DBP, MAP). We conclude that BRL 38227 shortens the ventricular parameters of conduction velocity and of repolarization and decreases BP, both in a dose-dependent manner. All doses were arrhythmogenic, suggesting that BRL 38227 has a low safety margin.
Asunto(s)
Antihipertensivos/efectos adversos , Arritmias Cardíacas/inducido químicamente , Benzopiranos/efectos adversos , Corazón/efectos de los fármacos , Pentobarbital , Pirroles/efectos adversos , Vasodilatadores/efectos adversos , Anestesia , Animales , Antihipertensivos/administración & dosificación , Benzopiranos/administración & dosificación , Cromakalim , Perros , Relación Dosis-Respuesta a Droga , Electrofisiología , Femenino , Corazón/fisiología , Hemodinámica/efectos de los fármacos , Inyecciones Intravenosas , Masculino , Canales de Potasio/efectos de los fármacos , Pirroles/administración & dosificación , Vasodilatadores/administración & dosificaciónRESUMEN
We have examined the ability of lemakalim to correct bupivacaine-induced cardiac electrophysiological impairment in an experimental electrophysiological model in closed-chest dogs. Two groups (n = 6) of pentobarbitone-anaesthetized dogs were given atropine 0.2 mg kg-1 i.v., and bupivacine 4 mg kg-1 i.v. over 10 s. Group 2 received also lemakalim 0.03 mg kg-1 i.v. Bupivacaine induced bradycardia, prolonged PR and His-ventricle (HV) intervals, QRS duration, QTc and JTc intervals, decreased left ventricular (LV) dP/dt max and increased LV end-diastolic pressure. Lemakalim reversed bupivacaine-induced PR, HV, QRS, QTc and JTc prolongation, and did not worsen bupivacaine-induced bradycardia and haemodynamic depression. We conclude that lemakalim can antagonize the main deleterious electrophysiological effects induced by a large dose of bupivacaine in anaesthetized dogs.
Asunto(s)
Benzopiranos/farmacología , Bupivacaína/antagonistas & inhibidores , Corazón/efectos de los fármacos , Pirroles/farmacología , Anestesia General , Animales , Atropina/farmacología , Cromakalim , Perros , Electrocardiografía/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Canales de Potasio/efectos de los fármacos , Factores de TiempoRESUMEN
Surgical rehabilitation of the upper limb in quadriplegia aims to restore prehension function. Surgical restoration always involves active extension of both elbow and wrist. Anesthesia, which first aim is to allow adequate surgical conditions, must adapt to the patient's disability. In this particular setting, regional anesthesia and especially brachial plexus block techniques represents our priority choice.
Asunto(s)
Anestesia de Conducción , Plexo Braquial , Codo/cirugía , Bloqueo Nervioso , Cuadriplejía/cirugía , Muñeca/cirugía , HumanosRESUMEN
Bupivacaine is more cardiodepressant than lidocaine. Nevertheless, the marked depression of contractility induced by bupivacaine cannot be completely explained by its electrophysiologic properties alone. Biophysical differences such as the greater lipid solubility of bupivacaine versus lidocaine must be taken into consideration. Perhaps more bupivacaine enters the cardiac cells and interacts with contractile processes. To test this hypothesis, the entry of lidocaine into the cells was facilitated by a membrane-permeant lipophilic anion, tetraphenylboron. We compared the spontaneous atrial rate and the contractile force of rabbit right atria bathing in solutions containing either 0.5 microgram/mL lidocaine or bupivacaine. Group 1 (n = 8) served to test the stability of the preparation. In group 2 (n = 6), tetraphenylboron (17 micrograms/mL) was added to Tyrode's solution; atrial rate was decreased by 8% and contractile force by 1.7%. In group 3 (n = 6), bupivacaine (0.5 microgram/mL) was added; bupivacaine decreased atrial rate by 11.3% and markedly depressed contractile force by 68.3%. In group 4 (n = 6), lidocaine (0.5 microgram/mL) was added; lidocaine did not change atrial rate but decreased contractile force by 6.0%. In group 5 (n = 6), both lidocaine and tetraphenylboron were added; atrial rate was decreased by 15.5% and contractile force was markedly depressed by 81.1%. In group 6 (n = 6), 0.2 mM adenosine triphosphate, tetraphenylboron, and then lidocaine were added; the addition of adenosine triphosphate partially counteracted the cardiodepressant effects of the combination of lidocaine and tetraphenylboron. Atrial rate was decreased by 10.4% and contractile force was depressed by 13.6%.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Bupivacaína/farmacología , Corazón/efectos de los fármacos , Contracción Miocárdica/efectos de los fármacos , Animales , Depresión Química , Interacciones Farmacológicas , Lidocaína/farmacología , Conejos , Tetrafenilborato/farmacologíaRESUMEN
The ability of clonidine and dobutamine to correct bupivacaine-induced cardiac electrophysiologic and hemodynamic impairment was evaluated in an experimental electrophysiologic model on closed-chest dogs. Five groups (n = 6) of pentobarbital-anesthetized dogs were given atropine (0.2 mg/kg IV). Group 1 was given a saline solution; all other dogs were given bupivacaine (4 mg/kg IV) over a 10-s period. Group 2 was given only bupivacaine. Group 3 was given clonidine (0.01 mg/kg IV) over a 1-min period. Group 4 was given a dobutamine infusion at 5 micrograms.kg-1.min-1. Group 5 was given the combination of clonidine and dobutamine. Bupivacaine induced bradycardia, prolonged atrioventricular conduction time (PR interval), atrioventricular node conduction time (AH interval), His-Purkinje conduction time (HV interval), and QRS duration. Bupivacaine decreased left ventricular (LV) dP/dt max and increased LV end-diastolic pressure (LVEDP). Clonidine improved QRS duration and HV interval but enhanced AH interval, bradycardia, and hemodynamic depression induced by bupivacaine. Dobutamine infusion improved LV dP/dt max but did not modify bupivacaine-induced ventricular electrophysiologic impairment. The combination of clonidine and dobutamine corrected not only the electrophysiologic impairment induced by bupivacaine but also the hemodynamic depression. As the HV interval and the QRS duration could be correlated with ventricular conduction velocities, we conclude that (a) clonidine reversed the slowing of ventricular conduction velocities induced by bupivacaine, and (b) the combination of clonidine and dobutamine was able to correct the cardiac disturbances induced by bupivacaine in anesthetized dogs.
Asunto(s)
Bupivacaína/antagonistas & inhibidores , Clonidina/farmacología , Dobutamina/farmacología , Sistema de Conducción Cardíaco/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Animales , Bupivacaína/sangre , Depresión Química , Perros , Combinación de Medicamentos , Electrocardiografía/efectos de los fármacos , Sistema de Conducción Cardíaco/fisiología , Concentración de Iones de HidrógenoRESUMEN
The intravascular injection of a large dose of bupivacaine induces electrophysiological cardiac impairment, mainly by slowing ventricular conduction velocity, and haemodynamic depression, by a decrease in myocardial contractility. When cardiotoxicity occurs, succinylcholine rapidly stops convulsions. However, the possible interactions between bupivacaine and succinylcholine on cardiac electrophysiology and haemodynamic status have never been investigated. Thus, we used an experimental electrophysiological model involving closed-chest dogs. Three groups (n = 6) of pentobarbital-anaesthetized dogs were given 0.2 mg.kg-1 atropine iv. Dogs in Group 1 were given saline. The others received 4 mg.kg-1 bupivacaine iv over ten seconds. Dogs in Group 2 were then given saline and those in Group 3 were then given 2 mg.kg-1 succinylcholine iv from one to two minutes after the administration of bupivacaine. The following electrophysiological variables were measured: heart rate represented by RR interval (RR), PR, atria-His (AH), and His-ventricle (HV) intervals, QRS duration, and QT interval corrected for heart rate (QTc). The following haemodynamic variables were measured: mean aortic pressure (MAoP), the peak of the first derivative of left ventricular pressure (LV dP/dt max), and LV end diastolic pressure (LVEDP). Comparison between Groups 1 and 2 showed that bupivacaine induced more than 100% HV interval lengthening and QRS widening (P less than 0.01), prolonged QTc interval by more than 25% (P less than 0.01), and decreased LV dP/dt max by more than 50% (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Anestesia Intravenosa , Bupivacaína/efectos adversos , Corazón/efectos de los fármacos , Pentobarbital/farmacología , Succinilcolina/farmacología , Animales , Aorta/fisiología , Presión Sanguínea/efectos de los fármacos , Bradicardia/inducido químicamente , Fascículo Atrioventricular/efectos de los fármacos , Perros , Interacciones Farmacológicas , Electrocardiografía/efectos de los fármacos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Masculino , Contracción Miocárdica/efectos de los fármacos , Factores de Tiempo , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
A common property of all Class I antiarrhythmic agents is the inhibition of the fast inward current INa. Consequently, ventricular conduction velocities are impaired and reentrant phenomena are counteracted. Unfortunately, these conductive pathway disturbances may also induce proarrhythmic effects and reduce cardiac contractility. Recent evidence indicates that a cholinergic agonist, carbachol, is able to correct in vitro both the duration of the action potential and the partial depolarization induced by lidocaine and quinidine in rabbit atria. In the present study, we demonstrated that i.v. carbachol is also a powerful agent in vivo for correcting conductive disturbances previously induced by four different Class I antiarrhythmic agents. The electrophysiological and hemodynamic parameters of ten groups of atropinized-anesthetized dogs, including six animals per group, were investigated. QRS duration, HV and V-St intervals were selected as in vivo indexes of ventricular conduction. Quinidine, procainamide, cibenzoline and flecainide were selected as representative agents of Class Ia and Ic antiarrhythmic drugs. In all treated groups, carbachol (1 mg/kg) was able to correct the indexes of ventricular conduction previously impaired by the antiarrhythmic drug used.
Asunto(s)
Anestesia , Antiarrítmicos/farmacología , Carbacol/farmacología , Sistema de Conducción Cardíaco/efectos de los fármacos , Animales , Circulación Coronaria/efectos de los fármacos , Perros , Electrocardiografía/efectos de los fármacos , Electrofisiología , Femenino , Ventrículos Cardíacos/efectos de los fármacos , MasculinoRESUMEN
The aim of the regional administration of opioids is to provide an efficient and prolonged analgesia. Then, opiates can be useful for postoperative analgesia and for the treatment of chronic pain of malignant origin. Analgesia is correlated with several adverse effects of which the most frequent are nausea and itching and the most severe is respiratory depression. Beside the adverse effects, other properties of opiates could be responsible of favourable effects which can be taken in advantage in specific indications. In the postoperative period, epidurally administered opioid can attenuate the neuroendocrine and metabolic responses to surgery and pain. This effect is responsible of a reduction of the resistance to insulin and of a better nutritional balance, especially after major abdominal surgical procedures. Opioids also act by a reduction of the motor functions of the bowel, which perhaps could reduce the incidence of anastomotic breakdowns. Finally, other effects have been reported, as anecdotes, such as the treatment of spasm after bilateral replantation of the ureters, neurologic bladder dysfunctions and enuresis. Spinal administration of opioids has also been used as a treatment of premature ejaculation.