A computerized anesthesia monitoring system in each of LDS Hospital's 19 surgery suites is letting patients breath a little easier.
Known as SARA (System for Anesthetic and Respiratory Analysis), the computerized equipment allows anesthesiologists to precisely monitor and report the levels of oxygen, nitrogen, nitrous oxide, carbon dioxide and the anesthesia gases - halothane, enflurane or isoflurane - that a patient inhales and exhales during surgery."With SARA, we're able to know exactly what concentrations of anesthetics a patient is receiving at any time during surgery," said Dr. Paul R. Seager, chairman of the hospital's Department of Anesthesia. "Without SARA, the administration of anesthesia is more of an art than a science. Anesthesiologists rely upon their professional experience, blood pressure measurements, pulse rates and other parameters and monitors.
"These traditional methods are still important, of course, but with SARA, we have a much broader data base to aid us in our decision making."
Seager reports that every patient reacts differently to anesthesia.
"Some people require more, others less. Traditionally, we give an anesthetic that takes into account the patient's age, weight, physical status and special medical problems, then tailor the anesthetic to the patient's responses," he said. "SARA provides exact measurements of inhaled anesthetics; every anesthetic can now be more accurately individualized to the patient, and the data received from SARA correlated to the patient's responses."
SARA monitors patients through a device within the anesthesia breathing circuit which delivers oxygen and anesthetic gases during an operation. This device is connected via a thin vacuum tube to a combination mass spectrophotometer and computer. The exhaled gases produced by a patient's respiration are analyzed, and the information is fed back to the display monitor in the operating room.
SARA even monitors itself. Every three hours, the system automatically runs its own internal calibration audit. If something doesn't check out perfectly, SARA notifies the anesthesiologist of the problem and turns itself off rather than risk returning inaccurate data to the display terminal. Such an event - which is rare - causes no disruption in patient care because the anesthesiologist is also using traditional monitoring devices as a backup.
Seager said that besides being more effective, SARA is more efficient because it reduces the amount of anesthetic agents being used - and that benefits the patient during and after surgery.
"All anesthetic agents can produce undesirable side effects on all organ systems," he noted. "The anesthesiologist's intent is to give the patient the minimum concentration necessary to maintain the required depth of unconsciousness."
Seager stressed that with SARA, specialists can deliver the optimum anesthetic dose and maintain it throughout the surgical procedure.
"The anesthesiologist wins because the delivery and monitoring equipment is more accurate; the surgeon wins because there are fewer disruptions resulting from anesthetic complications, and the patient wins because they recover consciousness quicker with fewer side effects," he said.