The rapid administration of vancomycin is associated with flushing and
hypotension, a consequence of histamine release. The manufacturer dis
courages administering vancomycin to anesthetized patients, stating th
at vancomycin aggravates the hypotensive effects of anesthetics. To te
st this, we randomly assigned 36 adults (ASA classes I through III) to
one of two groups: preinduction (Preind, n = 19) and postinduction (P
ostind, n = 17). Both groups received two different infusions: vancomy
cin (1 g/250 mL normal saline) and saline (250 mL normal saline) over
30-60 min. The Preind group received vancomycin before anesthesia was
induced and saline was administered immediately after anesthesia was i
nduced; for the Postind group, this order was reversed. This was done
in a double-blind fashion. The anesthetic induction was standardized b
y the intravenous administration of thiopental and vecuronium and anes
thetic maintenance by inhalation of nitrous oxide and enflurane. End-t
idal enflurane, heart rate (HR), and blood pressure (BP) were measured
every 3 min. Independent (unpaired) t-test was used in data analysis.
The groups did not differ significantly. We conclude that vancomycin
infusion may be given under anesthesia without significant adverse hem
odynamic consequences if administered over a 30-60 min period of time.