Anesthesia
Overview
Anesthesia (Korean: 마취; Hanja: 痲醉) is a medical practice that uses drugs to temporarily and reversibly block pain sensation, consciousness, and motor function, enabling patients to undergo surgery or invasive procedures without pain. Beyond simply eliminating pain, it is a comprehensive clinical management process that includes suppression of autonomic reflexes, muscle relaxation, and monitoring of vital functions. Today, anesthesia is a foundational technology in nearly every field, including surgery, obstetrics and gynecology, orthopedics, and internal medicine procedures, and specialists in anesthesiology and pain medicine oversee its administration and overall patient management.
Main Content
Etymology and History
The word "anesthesia" derives from the Greek "an-" (without) and "aisthesis" (sensation). Modern anesthesiology began with the so-called "Ether Day" of 1846, when the American dentist William Morton successfully performed a public operation using ether. Subsequently, through chloroform and cyclopropane, then halothane in the mid-20th century, and with the development of current inhaled anesthetics such as desflurane and sevoflurane and intravenous anesthetics of the propofol and fentanyl classes, safety and recovery speed have greatly improved.
Types of Anesthesia
1. General anesthesia: Loss of consciousness and blockade of pain throughout the entire body. Securing the airway via endotracheal intubation or laryngeal mask is typical, and it is used for major surgery such as cardiac, abdominal, and neurosurgery.
2. Regional anesthesia: Includes spinal anesthesia, epidural anesthesia, and peripheral nerve blocks, and is widely used for lower-limb, obstetric, and orthopedic surgery. Recently, ultrasound-guided nerve blocks have become standardized, improving accuracy and safety.
3. Local anesthesia: A method of directly applying or injecting local anesthetics such as lidocaine onto the skin or mucous membranes, used for small sutures, dental treatment, and the like.
4. Sedation (Monitored Anesthesia Care, MAC): A method of maintaining consciousness while relieving anxiety and pain, used for endoscopy, cataract surgery, and so on.
Anesthetic Drugs
- Inhaled anesthetics: sevoflurane, desflurane, isoflurane
- Intravenous anesthetics: propofol, etomidate, ketamine
- Analgesics: fentanyl, remifentanil, morphine, lidocaine
- Muscle relaxants: rocuronium, cisatracurium, succinylcholine
- Local anesthetics: lidocaine, bupivacaine, ropivacaine
These are usually administered in combination, and the dosage is adjusted according to the patient's age, weight, hepatic and renal function, and comorbidities.
Anesthesia Process
Anesthesia proceeds through the stages of ① preoperative evaluation (checking medical history, airway assessment, cardiopulmonary function, and fasting status), ② induction of anesthesia, ③ maintenance of anesthesia, ④ emergence and recovery, and ⑤ postoperative pain management. In particular, during the preoperative evaluation, identifying a difficult airway, a history of malignant hyperthermia, drug allergies, etc., is critical for safety. During surgery, the electrocardiogram, blood pressure, pulse oximetry, end-tidal carbon dioxide, body temperature, and degree of muscle relaxation are continuously monitored.
Risks and Complications
Common side effects include nausea and vomiting, chills, sore throat, and dizziness, while rare but serious complications include hypoxia, aspiration pneumonia, malignant hyperthermia, anaphylaxis, delayed emergence, intraoperative awareness, and nerve injury. Elderly and obese patients and those with cardiopulmonary disease or sleep apnea have a relatively higher risk, requiring individualized management.
Recent Trends
The key changes in the field of anesthesia in 2024–2025 are digitalization, precision, and improvement in the quality of recovery. First, as electroencephalogram-based depth-of-anesthesia monitoring and target-controlled infusion (TCI) have become widespread, drug administration has become more precisely personalized. Second, artificial intelligence-based hypotension prediction and automated drug infusion systems are moving beyond clinical research and being piloted in some hospitals. Third, with the spread of ultrasound-guided nerve blocks and continuous peripheral nerve block catheters, "opioid-sparing" strategies that reduce opioid use and postoperative complications are being emphasized. Fourth, as Enhanced Recovery After Surgery (ERAS) protocols become standardized, the role of the anesthesiologist is expanding to managing the entire perioperative pathway. Fifth, as the environmental impact of inhaled anesthetics with high global warming potential comes to the fore, the use of desflurane, low-flow anesthesia, and the introduction of anesthetic gas recovery systems are being discussed mainly in Europe. In addition, anesthesia management for high-risk elderly patients, obese patients, and chronic pain patients amid population aging is emerging as a major challenge, and research on safety management using wearable sensors and remote monitoring is also active. In Korea, the shortage of anesthesiologists and the disparity in access to labor analgesia (painless childbirth) are being addressed as policy issues.
Related Topics
- [[Anesthesiology and Pain Medicine]]
- [[General anesthesia]]
- [[Local anesthesia]]
- [[Propofol]]
- [[Postoperative pain management]]
- [[Airway management]]
- [[Malignant hyperthermia]]