Possible Interaction: Enflurane and Calcium Supplement

“In glycerinated muscle fiber, enflurane shifted the pCa-tension relation to the left in low calcium and suppressed maximally activated tension at high calcium concentration.”

“Because these results eliminate most alternative explanations for this phenomenon, the authors conclude that halothane, and probably also enflurane , increases the fraction of calcium released from the sarcoplasmic reticulum with each heart beat.”

“Halothane and enflurane mainly decrease intracellular calcium availability by a direct effect on sarcoplasmic reticulum, while isoflurane only decreases the transsarcolemnal calcium entry.”

“Of the volatile anesthetics, isoflurane (2.6 vol% or 0.57 mM) and enflurane (4.3 vol% or 1.25 mM) inhibited initial net Ca influx during K depolarization significantly more than halothane (1.7 vol% or 0.50 mM), which had no apparent effect.”

“ Enflurane depressed the Ca2+i transient amplitude more than isoflurane.”

“RESULTS Enflurane and isoflurane reduced electrically stimulated Ca2+i transients in a dose-dependent manner.”

“The reduction in the Ca2+i transient because of SR Ca2+ release was greater in enflurane than in equal concentrations of isoflurane.”

“These observations are consistent with the hypothesis that enflurane may impair calcium handling by the sarcoplasmic reticulum whereas propofol has little, if any, effect at this site.”

“Both halothane and enflurane decreased the calcium content of sarcoplasmic reticulum (SR) as measured by caffeine-induced calcium release.”

“Caffeine, halothane, enflurane , and isoflurane all decreased the total calcium content of myocytes by 10-70%.”