C. Newson et al., COMPARISON OF PROPOFOL ADMINISTRATION TECHNIQUES FOR SEDATION DURING MONITORED ANESTHESIA CARE, Anesthesia and analgesia, 81(3), 1995, pp. 486-491
Sixty-three outpatients undergoing breast biopsy procedures with local
anesthesia were randomly assigned to receive propofol by intermittent
bolus injections (n = 21), a conventional syringe infusion pump (n =
21), or a target-controlled infusion (TCl) device (n = 21) for intraop
erative sedation. In the first two groups, an initial intravenous (IV)
bolus of propofol (0.3 mg/kg) was administered and an attempt was mad
e to maintain the sedation level at an Observer's Assessment of Alertn
ess/Sedation (OAA/S) score of 3 or 4 with either intermittent bolus in
jections of propofol (10 mg) or a variable-rate infusion (25-100 mu g
. kg(-1). min(-1)). In the TCl group, the initial target concentration
of propofol was set at 2 mu g/mL and the target concentration was adj
usted between 1 and 4 mu g/mL in an attempt to maintain an OAA/S score
of 3 or 4. Recovery was assessed using clinical criteria, visual anal
og scales (VAS), and the digit-symbol substitution test (DSST). The ov
erall quality of sedation, operating conditions, and clinical recovery
profiles were similar in all three treatment groups. The anesthesiolo
gist had to intervene more frequently in the intermittent bolus inject
ion group than in the two infusion groups. We conclude that the use of
an infusion technique may allow the anesthesiologist more time for mo
nitoring the patient by decreasing the number of interventions necessa
ry to administer supplemental doses of the sedative medication during
the operation. However, the cost of the IV drug delivery system may be
come an increasingly important factor in the future.