Doppler Ultrasound can Reduce Hospital Stays
DALLAS, TX -- When used during major surgery to continually monitor and guide the administration of fluids during procedures, Doppler ultrasound can shorten hospital stays and allow patients to begin eating solid food sooner, researchers at Duke University Medical Center have found.
Careful monitoring of cardiac output and volume status during surgery is important, Duke anesthesiologist Dr. T.J. Gan says, because wide fluctuations up or down can lead to serious side effects, such as organ failure, shock or even death.
The new technology, esophageal Doppler ultrasound, provides anesthesiologists with more and better information about the patient's status during surgery and is far less invasive than the commonly used methods.
Gan prepared the results of his study for presentation Monday (Oct. 11) at the annual scientific meeting of the American Society of Anesthesiologists.
Much like the technology that allows physicians to visualize a baby within a pregnant mother or helps meteorologists follow weather patterns, the Doppler ultrasound provides detailed information on how well the heart is pumping and how much blood is circulating through the system.
To see is if this new technology could help physicians monitor patients during surgery, Gan tested 100 consecutive patients over a nine-month period who were undergoing surgeries that typically result in major blood loss. The fluid levels of half of the patients were maintained using information gained from the Doppler ultrasound, while the other 50 patients were monitored conventionally.
"By optimizing the administration of fluids to our patients, we can reduce the rate of post-operative complications," Gan said. "The reduction in complications translates into shorter hospital stays and quicker return to everyday life. The Doppler technology is less invasive and gives us more complete information about how the patient is doing intraoperatively."
Specifically, those patients whose treatment was guided by Doppler ultrasound left the hospital in five days, compared to seven days for conventionally treated patients. These patients also started eating solid food - a key indicator of recovery - in three days, compared to five days.
Once patients were under the influence of general anesthesia, researchers threaded a pencil-thin flexible probe down the esophagus to a location behind the heart. From this location, the probe relays a beat-by-beat analysis of the amount of blood being pumped by the heart to a monitor that is observed by anesthesiologists taking care of the patient.
Traditional methods for obtaining similar information during surgery involve inserting a catheter through the skin to a position in a major artery near the heart. This is invasive and technically demanding and is associated with a higher complication rate, the researchers say.
"The Doppler ultrasound is fairly simple to use and doesn't take long for doctors to learn how to interpret the results," Gan said. "The equipment appears to be cost effective, and it should be applicable in any hospital that performs major surgeries."
The device, which has FDA approval, is manufactured by Deltex Medical Inc., Irving, Texas, who, along with the Duke department of anesthesiology, funded the current study.