Korean J Anesthesiol.  2012 Nov;63(5):425-430. 10.4097/kjae.2012.63.5.425.

The effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing total knee replacement surgery

• Song I
• Kim DY
• Kim YJ

• KMID: 1767210
• DOI: http://doi.org/10.4097/kjae.2012.63.5.425

Abstract

BACKGROUND
Inflation and deflation of a pneumatic tourniquet used in total knee replacement surgery induces various changes in patient's hemodynamic and metabolic status, which may result in serious complications, especially in aged patients. Near-infrared spectroscopy (NIRS) is a monitoring device designed to estimate the regional cerebral oxygen saturation. We evaluated the effect of tourniquet deflation on hemodynamics and regional cerebral oxygen saturation in aged patients undergoing total knee replacement surgery, using NIRS.
METHODS
Twenty-eight American Society of Anesthesiologists physical status I or II patients, over the age of sixty-five years undergoing total knee replacement surgery, were included. Under general anesthesia, the mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), stroke volume (SV), and regional cerebral oxygen saturation (rSO2) were recorded before induction of anesthesia and every 2 min after tourniquet deflation for 20 min. Arterial blood gas analysis was performed 5 min before, in addition to 0, and 10 min after tourniquet deflation.
RESULTS
The decrease of rSO2 was not significant during 20-min deflation period. MAP, CO and SV showed significant decrease during 2 to 12, 4 to 6 and 2 to 6-min period after tourniquet deflation, respectively (P < 0.05). There was no relationship between a maximal decrease of MAP and rSO2.
CONCLUSIONS
In aged patients undergoing total knee replacement surgery under general anesthesia, tourniquet deflation caused significant changes in hemodynamic and metabolic status, but not in regional cerebral oxygen saturation. It is recommended to monitor neurologic status, as well as hemodynamic and metabolic status to avoid serious complications, especially in aged patients.

Keyword

Aged; Hemodynamics; Near-Infrared spectroscopy; Tourniquet

MeSH Terms

Aged
Anesthesia
Anesthesia, General
Arterial Pressure
Arthroplasty, Replacement, Knee
Blood Gas Analysis
Cardiac Output
Equipment Design
Heart Rate
Hemodynamics
Humans
Inflation, Economic
Organothiophosphorus Compounds
Oxygen
Spectroscopy, Near-Infrared
Stroke Volume
Tourniquets
Organothiophosphorus Compounds
Oxygen