Minimum alveolar concentrations and hemodynamic effects of two different preparations of sevoflurane in pigs.
BACKGROUND
Original sevoflurane (Sevo A) is made with water, while a generic sevoflurane (Sevocris) is produced with propylene glycol as a stabilizing additive. We investigated whether the original and generic sevoflurane preparations differed in terms of their minimum alveolar concentration (MAC) values and hemodynamic effects.


METHODS
Sixteen pigs weighing 31.6+/-1.8 kg were randomly assigned to the Sevo A or Sevocris groups. After anesthesia induction via mask with the appropriate sevoflurane preparation (6% in 100% oxygen), the MAC was determined for each animal. Hemodynamic and oxygenation parameters were measured at 0.5 MAC, 1 MAC and 1.5 MAC. Histopathological analyses of lung parenchyma were performed.


RESULTS
The MAC in the Sevo A group was 4.4+/-0.5%, and the MAC in the Sevocris group was 4.1+/-0.7%. Hemodynamic and metabolic parameters presented significant differences in a dose-dependent pattern as expected, but they did not differ between groups. Cardiac indices and arterial pressures decreased in both groups when the sevoflurane concentration increased from 0.5 to 1 and 1.5 MAC. The oxygen delivery index (DO(2)I) decreased significantly at 1.5 MAC.


CONCLUSIONS
Propylene glycol as an additive for sevoflurane seems to be as safe as a water additive, at least in terms of hemodynamic and pulmonary effects.
Laboratory of Medical Investigation, LIM/08 Anesthesiology, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Denise A
DA
Otsuki
Denise T
DT
Fantoni
Carla
C
Holms
Jose Otavio C
JO
Auler
D018685:Anesthetics, Inhalation / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D008738:Methyl Ethers / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D010100:Oxygen / Q000378:metabolism; D019946:Propylene Glycol / Q000494:pharmacology*; D011650:Pulmonary Alveoli / Q000378:metabolism; D011897:Random Allocation; D012119:Respiration / Q000187:drug effects; D000077149:Sevoflurane; D013552:Swine; D013997:Time Factors
D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D019946:Propylene Glycol; D010100:Oxygen