[Comparison of hemodynamic changes in acute intoxication with intravenous bupivacaine and ropivacaine in swine].
OBJECTIVE
Pure levorotatory ropivacaine was introduced to provide a safer alternative to bupivacaine in regional blocks. The objective of this study was to compare the hemodynamic repercussions after the intravenous administration of both agents in swine, simulating the intoxication that can be seen during regional blocks in humans.


METHODS
Large-White swine were anesthetized with thiopental, followed by endotracheal intubation and controlled mechanical ventilation. Hemodynamic parameters included non-invasive blood pressure and catheterization of the pulmonary artery. After 30 minutes, animals were randomly divided into two groups, and 4 mg.kg-1 of one of the agents was administered intravenously without the knowledge of the investigator. Hemodynamic parameters were evaluated at rest and 1, 5, 10, 15, 20, and 30 minutes after intoxication.


RESULTS
The hemodynamic repercussions of acute bupivacaine intoxication were more important and prolonged than in ropivacaine intoxication. With bupivacaine, the cardiac index showed greater and more prolonged reduction, mean arterial pressure and heart rate had more prolonged reduction, central venous pressure showed a more prolonged increase, and pulmonary wedge pressure increased more for more prolonged time. The impact on the systemic vascular resistance index showed that vasomotricity was partially maintained, increased in both groups, and, paradoxically, was greater and longer-lasting with bupivacaine.


CONCLUSIONS
In swine, ropivacaine caused less hemodynamic repercussions than bupivacaine when the same doses were administered intravenously.
Departamento de Cirurgia, FCM, UNICAMP.
Marcos De Simone
Mde S
Melo
William Adalberto
WA
Silva
Ana Cristina de
AC
Moraes
Artur
A
Udelsmann
D000577:Amides / Q000008:administration & dosage / Q000633:toxicity*; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D002045:Bupivacaine / Q000008:administration & dosage / Q000633:toxicity*; D006439:Hemodynamics / Q000187:drug effects*; D007275:Injections, Intravenous; D000077212:Ropivacaine; D013552:Swine
D000577:Amides; D000779:Anesthetics, Local; D000077212:Ropivacaine; D002045:Bupivacaine