Desflurane controls the hemodynamic response to surgical stimulation more rapidly than isoflurane.
OBJECTIVE
To compare the control of hemodynamic response to surgical stimulus of desflurane to that of isoflurane.


METHODS
Prospective randomized study.


METHODS
Operating room of a major U.S. teaching hospital.


METHODS
59 ASA status I, II, and III patients 18 to 80 years of age and were undergoing orthopedic or intra-abdominal surgical procedures of 1 or more hours in duration.


METHODS
Group 1 (n = 29) received desflurane in oxygen (O2) for their surgical procedure. Group 2 (n = 30) received isoflurane in O2 for their surgical procedure. Thiopental sodium 4 mg/kg and fentanyl 3 micrograms/kg provided induction; vecuronium 0.1 mg/kg facilitated intubation. Prior to incision the volatile anesthesia drug was titrated to maintain systolic blood pressure (SBP) within 20% of preinduction (baseline) values. Any time after incision, an SBP increase greater than 20% of baseline was treated with a 30% increase in inspired anesthetic concentration for 3 minutes, or until SBP was within 10% of baseline. Another three 30% increases were allowed at 3 minute intervals to return SBP to 10% of baseline. If four 30% increases did not return SBP to 10% of baseline, additional fentanyl up to 5 micrograms/kg or labetalol in 5 mg increments was given.


RESULTS
Measurement of hemodynamics and anesthetic concentration occurred every 2 minutes prior to skin incision and every 5 minutes thereafter. Measurement of hemodynamics and anesthetic concentration occurred every minute during treatment of blood pressure (BP) response to surgical stimulus. Desflurane allowed for more rapid control of BP response to surgical stimulus median 2 minutes (range 1 to 12 minutes) for desflurane versus 6 minutes (range 1 to 12 minutes, p = 0.011). The desflurane group required fewer 30% incremental anesthetic increases than the isoflurane group (1.8 versus 2.5, p = 0.016) to control increased SBP. End tidal/inspired drug concentration ratios were closer to unity in the desflurane patients both before (0.94 versus 0.80) and after (0.86 versus 0.70) changes in drug concentration to treat increased SBP.


CONCLUSIONS
Anesthetic depth can be more rapidly titrated with desflurane compared to isoflurane. Alveolar/inspired concentration ratio approaches unity more rapidly with desflurane anesthesia.
Bennett
J A
JA
Department of Anesthesiology, Medical College of Pennsylvania, Philadelphia, USA.
Mahadeviah
A
A
Stewart
J
J
Lingaraju
N
N
Keykhah
M M
MM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000769:Anesthesia, Inhalation; D018685:Anesthetics, Inhalation; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D000077335:Desflurane; D005260:Female; D006439:Hemodynamics / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D007432:Intraoperative Period; D007530:Isoflurane / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013514:Surgical Procedures, Operative / Q000009:adverse effects*
D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane