Modificaciones de la respuesta cardiovascular con la inserción de la mascarilla laríngea y tubo endotraqueal / Cardiovascular responses to laringeal mask versus endotracheal intubation

Se estudiaron 20 pacientes entre 15 - 65 años de edad, asignados aleatoriamente en dos grupos con el objeto de determinar los cambios hemodinámicos a la inserción de mascarilla laríngea versus tubo endotraqueal, bajo anestesia general con Sevoflurano/fentanyl/O2. El grupo I (n= 10) fue el grupo de estudio al que se colocó la mascarilla laríngea y se compararon todas las variables hemodinámicas contra el grupo II (tubo endotraqueal) como grupo control. Se evaluó asi mismo los requerimientos anestésicos del sevoflurano en lo que respecta a la CAM. La respuesta cardiovascular producida con la inserción de la mascarilla laríngea fue mucho menor que la provocada por la colocación de tubo endotraqueal. Los requerimientos anestésicos del sevoflurano y el CAM fueron definitivamente menores para el grupo de mascarilla laríngea que para el grupo control

Avaliaçåo do risco de complicaçöes em duas técnicas de hipotensåo controlada em cirurgia ortognática / Risk evaluation of two techniques of controlled hypotension in ortognathic surgery

Background and Objectives - Some surgical procedures require a reduction of bleeding in order to obtain a better exposure of the surgical field. Controlled hypotension is the most used technique for this purpose, but the risk-benefit of such technique should always be considered for each patient, This study was propesed in order to analyse the complications associated with two anesthetic techniques of controlled hypotension used for ortognathic surgery. Methods - Thirty-two patients aged 14 to 53 years, submitted to ortognathic surgery, were studied. Patients were randomised into two-groups in which the variable was the halogenated agent used (halothane or isoflurane). The studied parameters were: BP, HR, CVP, ECG, diuresis, temperature and pulse oxymetry. Measurements were obtained at the following moments: pre-induction, 2 and 4 hours intraoperativelly. Results - Complications were more frequent with halothane, which determined a higher incidence of arrythmias, hypotension and vasopressor consumption. In this group, 60 per cent of the patients received vasopressors and 20 per cent developed junctional rhythm. Conclusion - The technique which used isoflurane determined less complications and proved to be safer than the one in which halothane was used.

Efeitos do sulfato de magnésio na hemodinâmica cardiovascular de cåes anestesiados com pentobarbital sódico / Effects of magnesium sulphate on the cardiovascular hemodynamics of dogs anesthetized pentobarbitone

Background and Objectives - A controversy exists in the literature regarding the effects of the acute administration of magnesium on the cardiovascular system of animals and humans. The purpose of this study was to evaluate the effects of hypermagnesemia on the cardiovascular hemodynamics of dogs. Methods - Sixteen mongrel dogs were anesthtized with pentobarbitone 30mg.kg-1 and submitted to volume expansion with Ringer's solution (0.4ml.kg-1.min-1) and mechanical ventilation with room air. In this model, the hemodynamic repercussions of the following drugs and doses were studied: pentobarbitone 5mg,kg-1 - Group 1, control - and the association of pentobarbitone and magnesium sulphate (MS), at the dose of 140 mg.kg-1, injected in 15 minutes, followed by an infusion of 80 mg.kg-1.h-1 - Group 2. The parameters studied were: heart rate, blood pressure, inferior vena cava pressure, cardiac index, systolic index and peripheral resistance index, evaluated at 5 different moments: 15(M1), 30(M2), 60(M3) and 75(M4) minutes after the first supplementary dose of pentobarbitone and 15 minutes (M5) after the second supplementary dose. In group 2, the moments M3, M4, M5 corresponded to 15, 30 and 60 minutes after the priming dose of magnesium sulphate. Results - Group 1 animals exhibited tachycardia since the beginning of the experiment. There was a decrease in the cardiac index, in the systolic index and an increase in the inferior vena cava pressure. group 2 animals also exhibited tachycardia, but heart rate decreased after MS infusion. The blood pressure and the peripheralresitance index decreased. The systolic index increased and the cardiac index decresead only at he end of the experiment. Conclusions - The antiadrenergic effects of Ms could have been responsible for the decrease in heart rate. The vasodilating effects of the magnesium induced the decrease in the peripheral resistance index. The vasodilating effects of the magnesium induced the decrease in the peripheral resistance index. The systolic index increased, showing that myocardial depression did not occur.

Traumatismos de los grandes vasos: su incidencia y significación en la patología cardiovascular traumática / Great vessels injuries

Desde enero de 1985 a enero de 1990 se atendieron un total de 89 pacientes con lesiones vasculares y 25 con heridas cardíacas. De ellos, 12 presentaban lesiones de los grandes vasos intratorácicos. Estos corresponden principalmente a pacientes de sexo masculino, destacando dos grupos bien diferenciados dependiendo si la lesión es arterial o venosa. En las lesiones arteriales la principal es producto de accidentes de tránsito en pacientes jóvenes y corresponde a ruptura traumática de la aorta torácica. En las lesiones venosas, destacan en importancia las yatrogenias por procedimientos invasivos. Los procedimientos de apoyo diagnóstico más utilizados fueron la TAC en 8 casos y angiografía en 2. La TAC demostró ser el procedimiento de elección para la determinación topográfica de la ruptura aórtica. A pesar de cumplir con el principio de abordar de forma inmediata al paciente hemodinámicamente inestable con equipo quirúrgico idóneo, cuatro de los cinco pacientes fallecen en quirófano, coincidiendo con su condición de politraumatizados