Korean J Anesthesiol.  2009 May;56(5):543-551. 10.4097/kjae.2009.56.5.543.

Response of cerebral oximetry to increase in alveolar concentration of desflurane: effect of remifentanil and cerebrovascular CO2 reactivity

• Lee JH
• Lee Y
• In J
• Chung SH
• Shin HI
• Lee K
• Kim KO
• Cho H

• KMID: 1782593
• DOI: http://doi.org/10.4097/kjae.2009.56.5.543

Abstract

BACKGROUND: It is known that sympathetic stimulation and increase in cerebral blood flow velocity can be induced by desflurane. Cerebral oxygen balance could be disturbed during desflurane induction. Aim of this study was to elucidate that cerebral oxygen imbalance induced by desflurane mask induction can be reduced by combination of remifentanil and hypocapnia.
METHODS
Twenty ASA 1-2 subjects were allocated randomly into 5 groups divided by concentration of remifentanil (0.0, 0.5, 1.0, 1.5, and 2.0 ng/ml). After confirmation of attaining proposed concentration of remifentanil, propofol and vecuronium were administered and mechanical ventilation was done with 8% desflurane with facial mask. Subsequently, changes in regional cerebral oxygen saturation (DeltarSO2), arterial blood pressure, heart rate, cardiac index, estimated alveolar concentration of desflurane (PDESF), and end-tidal concentration of carbon dioxide (PETCO2) were recorded for the following 10 minutes. According to concentration of desflurane and remifentanil, DeltarSO2 and hemodynamic factors were checked.
RESULTS
During desflurane induction, changes in cerebral oximetry reached up to +10% (6 [first quartile], 13 [third quartile]). Arterial blood pressure, heart rate, and cardiac index were changed within clinical ranges. The DeltarSO2 showed S-shaped increasing pattern according to increasing PDESF. Hypocapnia and concentration of remifentanil reduced the maximum DeltarSO2 (P = 0.0046, P = 0.0060). Hypocapnia also shifted the curve to left (P = 0.0001).
CONCLUSIONS
During 8% desflurane induction, regional cerebral oxygen saturation (rSO2) increases maximum +25%. Hypocapnia and use of remifentanil can reduce the increase in regional cerebral oxygen saturation.

Keyword

Cerebral blood flow; Cerebral oximetry; Desflurane; Hypocapnia; Nonlinear mixed model; Remifentanil

MeSH Terms

Arterial Pressure
Blood Flow Velocity
Carbon Dioxide
Heart Rate
Hemodynamics
Hypocapnia
Isoflurane
Masks
Oximetry
Oxygen
Piperidines
Propofol
Respiration, Artificial
Vecuronium Bromide
Carbon Dioxide
Isoflurane
Oxygen
Piperidines
Propofol
Vecuronium Bromide