"Anesthesia involves the total loss of feeling or sensation," explained Anesthesiologist James Bachmeier, M.D. "It is primarily associated with the loss of painful sensations, which allows surgery or procedures to be performed without causing pain.
"There are different types of anesthesia. Local anesthesia is rendering a local area or part of the body insensitive to pain or sensation. General anesthesia involves causing complete unconsciousness and relaxation of the entire body, as well as a loss of painful sensations.
"The role of an anesthesiologist is to provide comprehensive anesthesia care to a patient who is undergoing a surgical or diagnostic procedure," Dr. Bachmeier added. "Sometimes anesthesiologists manage the anesthesia directly and sometimes they oversee the administration of anesthesia by specially trained professionals like nurse anesthetists. However, the anesthesiologist is responsible for the overall care of the patient throughout the entire time the anesthetic is given and during the recovery period."
Patients play an important role as partners in their anesthesia experience. "Before surgery, an anesthesiologist will evaluate the patient's medical history and perform a physical examination to determine the appropriate anesthesia plan," Dr. Bachmeier advised. "It is helpful if patients can describe any problems that they may have experienced with the use of previous anesthetics, along with current prescription medications or over-the-counter medications being taken. This information is very important so that the anesthesiologist can identify any medical risk factors that must be taken into account, such as allergies, chronic lung disease or heart disease, diabetes, or thyroid disease.
"In addition, patients need to provide an accurate report of past hospitalizations, surgical procedures, family-related problems with anesthesia, diagnostic tests, medications being taken and any concerns that may have been raised regarding the use of previous anesthetics. This conversation is known as 'informed consent,' and provides the opportunity to discuss what to expect, along with reviewing the risks and benefits of available anesthesia treatment options."
After the pre-surgery evaluation is complete, the patient is taken to the operating room. The anesthesia professional then attaches several devices to monitor the patient's physical well being, including an electrocardiogram or EKG, a blood pressure cuff, and blood oxygen saturation probe.
"During your surgery, your anesthesia professional will carefully monitor your vital signs, such as your heart rate, breathing rate, and blood pressure, to help gauge the depth of anesthesia," Dr. Bachmeier continued. "Multiple tools will be used to determine if you are getting a sufficient amount of anesthetic medication to keep you unconscious during your procedure.
"For example, special brain wave monitoring devices are available to help determine that a patient does not become awake during a procedure. The brain creates electrical waves as it works, and we know that the use of anesthetics changes the pattern of these brain waves. Specially designed brain wave monitors detect this brain wave activity and use a complex mathematical calculation to help tell the anesthesiologist if the patient is considered to be asleep or not."
At Salem Community Hospital, the BIS monitor is used to help measure the effects of anesthesia drugs on the brain during surgery. "Prior to starting surgery, a specially designed sensor is placed on the person's forehead, using simple stick-on patches attached to the skin," continued Dr. Bachmeier. "These sensors help conduct the electrical signals produced by the brain into a special monitoring device, much like EKG patches do for the heart. Together the sensors and monitor measure the person's brain activity and then compute a number between 0 and 100, which corresponds to the person's level of consciousness, known as the BIS value.
"Information from your brain waves indicates how you are responding to the anesthesia, so that the amount of medication can be adjusted if needed, in order to prevent you from getting too much or too little anesthesia."
Although it is serious, anesthesia awareness is very uncommon and is estimated to occur in some degree at a frequency of about 1 to 2 people out of 1,000. "Awareness under general anesthesia means becoming conscious or awake during some part of your operation," he said. "Different people respond to anesthesia in different ways, just like different people respond to prescription medications, alcohol, or over-the-counter drugs in different ways.
"A variety of factors can contribute to anesthesia awareness, such as unforeseen drug interactions or the person's metabolism rate. However, your anesthesia professional is present throughout the entire operation and continuously monitors your condition. He or she uses clinical judgment and experience to ensure that you are receiving enough anesthetic to keep you unconscious, but not too much so that you do not suffer serious side effects.
"No technology exists that can completely guarantee that a person will not experience anesthesia awareness, but anesthesia use today is safer than ever before due to advances in technology and adherence to patient safety standards," Dr. Bachmeier concluded. "Your anesthesia professional will help guide you through your surgery by relying on his or her clinical experience, training and judgment, combined with the use of advanced technology and patient safety practices."
James Bachmeier, M.D., is a board certified anesthesiologist, affiliated with Salem Community Hospital's active medical staff and associates in anesthesia, 3622 Belmont Avenue in Youngstown, 330- 759-9350.