What is minimal alveolar concentration?
Minimal alveolar concentration (MAC) is a test for determining the strength of the anesthetic compound during surgery. Specifically, it relies on how a given substance keeps at least half of the patients tested immobile. Created in the 1960s, the test can be carried out while people are awake, asking questions or searching for answers to stimuli. MAC can also be determined whether someone is responding to a surgical cut. The trend of lower values towards anesthetic drugs that have higher efficiency, and minimal alveolar concentration tends to reduce the elderly person you get, which means that less anesthetic is necessary to stop muscle movement and pain.
The typical measurement process takes 15 minutes. Once anesthetic gases are mixed evenly in the lungs, blood and brain, surgeons can convince that minimal alveolar concentrations have been determined. Mac substance is higher, the less soluble. The more soluble types of anesthesia have lower efficiency because they are vseven more and easier decaying. This discovery was carried out at the beginning of the 20th century and is called Meyer -overton hypothesis.
other than age has few physical factors affect Mac. Whether the subject is male or woman, it does not matter, although pregnant women have lower tolerance to anesthesia. Height and weight are not factors. It has also been observed that conditions such as hypothermia, hypothyroidism and low blood pressure may strengthen the effects of anesthetic substances, so less.
The aim of minimal alveolar concentration is to determine the basic line of effect of different types of anesthesia. Depending on the drug used, different parts of the nervous system are affected. Most anesthetics work in the spinal cord, so the numbness of the connection to the brain does not stop reflexive movements. Surgical patients sometimes say they were aware of what was happening during surgery, but consciousness is affected by different processes than greateron types of inspection of anesthesia.
patients can unknowingly create memories while they are under anesthesia. Such drugs block memories when someone wakes up, so sounds are not usually remembered, even if they are heard during the operation. People sometimes remember what things feel, but once a minimal alveolar concentration has been achieved, the pain is not processed. It is difficult to determine exactly how much information is maintained in memory during an anesthetic state, so surgeons must always remember MAC for each individual patient.