Anesthesia plays a crucial role in enabling surgical and interventional procedures by swiftly and safely providing pain control, alleviating anxiety, and ensuring muscle relaxation. An anesthesia provider also maintains physiological stability during the perioperative period, including stable blood pressure, adequate oxygen levels, proper ventilation, and maintaining body temperature, which is essential for patient safety and successful surgery. Prior to scheduled anesthesia, patients undergo evaluation by an anesthesia provider to assess their medical condition, readiness for the procedure, and to devise strategies to mitigate risks, and create a personalized anesthesia plan.
The American Society of Anesthesiologists (ASA) physical status classification system is a valuable tool in assessing the overall perioperative risk for patients based on their medical conditions. Patients are categorized based on the extent to which their medical issues affect their physiological condition. Higher ASA physical status correlates with increased risks of complications, longer hospital stays, higher costs, and even mortality.
Over the years, advancements in anesthesia equipment, monitoring, techniques, and safety culture have significantly reduced anesthesia-related mortality rates. Factors influencing the choice of anesthesia technique include the nature of the surgery, expected duration, patient’s medical history and preferences, plans for postoperative pain management, and the expertise of the anesthesia team. There are four major types of anesthesia. General anesthesia (GA) is used for major surgeries such as knee-replacement and open-heart surgery. Intravenous (IV) sedation is used for minor procedures such as colonoscopies. Regional anesthesia is used to number a certain part of the body, such as for surgeries of the arm, leg, or abdomen. Local anesthesia is used for minor procedures such as mole removal; a small area is numbed, but patients remain alert and oriented.
What kind of anesthesia is administered depends on each individual case, considering patient factors as well as provider preferences. However, ongoing research continuously improves knowledge and practices. For instance, neuraxial anesthesia shows promise in enhancing outcomes for hip and knee arthroplasty. GA remains the primary choice for major or prolonged surgeries, especially when deep sedation or limited airway access is required. However, for minor procedures, other options like neuraxial anesthesia or local anesthesia may be more suitable.
Each type of anesthesia carries its own set of advantages and risks, which must be carefully considered. Combining techniques, such as GA with epidural or peripheral nerve blocks, can offer optimal intraoperative conditions and effective postoperative pain management.
IV and inhalation agents are commonly used for induction and maintenance of GA, often in combination to minimize the dose of any single agent. Peripheral nerve blocks are frequently employed for surgical anesthesia, particularly in extremity surgeries. Intravenous regional anesthesia (IVRA) serves as an alternative for short procedures on the hand and forearm, although its usage is less common for foot or ankle surgeries due to tourniquet pain and duration limitations.
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