Anesthesia: The invisible force that protects life safety

Author: Wu Ping, Jingmen Central Hospital, Hubei Province

Reviewer: Yang Changming, Chief Physician of Jingmen Central Hospital, Hubei Province, Member of the Standing Committee of the Grassroots Committee of the Chinese Society of Cardiothoracic and Vascular Anesthesiology

In the silent operating room, every breath and heartbeat carries the weight of life. Anesthesia, as a key part of surgical operations, is not only a guardian of life, but also an important bridge connecting patients and surgical safety.

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1. Application fields of anesthesia

1. Surgery: Almost all surgical operations require anesthesia, from simple removal of local masses to complex cranial and cardiac surgeries.

2. Pain treatment: Pain is a common symptom of many diseases and traumas, which seriously affects the quality of life of patients. Anesthesiologists use various anesthetic drugs and techniques, such as nerve blocks and epidural anesthesia, to reduce or eliminate the patient's pain and improve the patient's comfort.

3. Special examinations and treatments: When conducting more delicate medical operations such as endoscopic examinations, invasive radiological examinations, and radiotherapy positioning, awake patients will experience greater psychological burden and physical discomfort. At this time, anesthesia can be used to help patients complete these diagnostic and treatment operations in a relaxed state.

4. Childbirth: The pain during childbirth is widely acknowledged to be severe and unbearable for most women. With the advancement of modern anesthesia technology, the pain during childbirth can be alleviated by using safe and effective anesthetic drugs and techniques, while keeping the woman conscious and not affecting her cooperation during childbirth and the health of the fetus.

5. Sedation assistance in pediatric diagnosis and treatment: For young children who are unable to cooperate well with examinations and treatments, anesthesia can help them complete medical procedures such as CT, MRI and other examinations and dental treatments that require them to complete independently in a safe and painless state.

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2. Surgery has “big or small”, but anesthesia has no “big or small”

Although surgeries vary in size, the risk management of anesthesia must be strictly carried out. Different patients' physical constitutions, medical histories, and surgical conditions may affect the effect and safety of anesthesia. Therefore, it is crucial to fully evaluate and avoid potential risks in anesthesia before surgery. Understanding common high-risk factors and their countermeasures is the key to ensuring the safety of surgical anesthesia.

1. History of allergies: Patients who have been allergic to anesthetic drugs or other drugs and items used during surgery (such as iodine, alcohol, and rubber products) should avoid using drugs and items that may cause allergic reactions.

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2. Respiratory diseases: Patients with severe asthma, chronic obstructive pulmonary disease or other serious respiratory diseases must strictly abstain from smoking and expectoration before surgery, and receive targeted drug treatment to reduce the risk of respiratory spasm caused by hypersensitive airways during the perioperative period.

3. Cardiovascular diseases: Patients with unstable angina, recent myocardial infarction, severe arrhythmias or heart failure who require non-emergency surgery should undergo relevant examinations, careful evaluation, adjustment of cardiovascular medications, and relevant measures for arrhythmias before surgery. Surgery should be scheduled after the patient's cardiac function improves.

4. Digestive system diseases: Patients with gastrointestinal obstruction, gastrointestinal bleeding, or recent gastrointestinal surgery need to make adequate preoperative preparations and develop a strict anesthesia plan before anesthesia to avoid risks such as aspiration.

5. Neurological diseases: Certain neurological diseases, such as spinal cord injury and intracranial hypertension, may aggravate the patient's adverse reactions to anesthetic drugs, leading to malignant hypotension and bradycardia during anesthesia. Therefore, such patients need to be treated in advance, and the surgical process should be closely monitored and intervened in time.

6. Obesity: Clinically, a body mass index (BMI) ≥ 28 kg/m² is defined as obesity. Regardless of the type of surgery, obese patients face a higher risk of perioperative complications, such as dyspnea and cardiovascular complications. Therefore, they need to pay special attention to perioperative anesthesia management. Good airway protection and a detailed anesthesia management plan are the key to ensuring a smooth perioperative period.

7. Pregnancy: Especially in the early and late stages of pregnancy, the choice of anesthetic drugs and methods and perioperative anesthesia management must be particularly cautious to ensure the health and safety of the mother and fetus.

8. Drug dependence or abuse: For patients who use opioids, alcohol or other substances for a long time, anesthesiologists need to pay attention to adjusting the dosage of anesthetic drugs and carry out relevant monitoring.

9. Metabolic and endocrine diseases: Diseases such as diabetes, hyperthyroidism or hypothyroidism, and adrenal insufficiency may affect the metabolism and effects of anesthetic drugs and increase the risk of complications. Therefore, such patients should be monitored more closely during the perioperative period and actively treated symptomatically.

3. Fasting time before anesthesia

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1. Solid food: Adults and children aged 6 years and above usually need to fast for at least 6 to 8 hours before anesthesia. Children under 6 years old need to fast for 4 to 6 hours.

2. Clear water or transparent liquid: You can drink it in moderation 2 to 4 hours before anesthesia.

3. Infants who are breastfeeding: usually need to fast for 4 hours before anesthesia.

4. Infants fed with formula or solid food: It is recommended to fast for 6 hours before anesthesia.

5. Some necessary medicines: such as those for the treatment of hypertension, diabetes, etc., can be taken with a small amount of water before anesthesia or discontinued. Specific instructions should be strictly followed by the doctor.

6. Fried, fatty and meaty foods: It is recommended to fast for 8 hours before anesthesia.

4. Choice of anesthesia method

1. General anesthesia: referred to as "general anesthesia", most surgeries require general anesthesia, such as laparoscopic surgery, cranial surgery, heart surgery, etc. During general anesthesia, the patient is in a deep sleep state and will not feel pain. The anesthesiologist will monitor the vital signs throughout the whole process. After general anesthesia surgery, the patient needs to lie flat, and the patient can get out of bed and move around according to the doctor's advice after the patient's limbs have recovered their ability to move and there are no adverse reactions such as drowsiness and dizziness.

2. Local anesthesia: This is called "local anesthesia" for short. It is suitable for minor surgeries, such as tooth extraction, local lipoma removal, etc. This type of anesthesia is used to numb the surgical site to ensure painless surgery. During local anesthesia surgery, the patient is always awake.

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3. Regional anesthesia: Similar to local anesthesia, regional anesthesia covers a wider range, usually referring to spinal anesthesia and nerve block anesthesia. By blocking the conduction of nerve impulses in a certain surgical area, the patient loses the sensation in the surgical area. It is often used in cesarean sections, artificial hip replacements, limb replantation and other surgeries.

5. Why do some general anesthesia surgeries require endotracheal intubation?

For some general anesthesia surgeries that require a long operation time, have a potential risk of aspiration, and may affect gas exchange, inserting a tracheal tube after anesthesia induction is a key step to ensure that the patient's airway remains open during the operation. The anesthesiologist will monitor the patient's breathing and anesthesia status throughout the process and make adjustments as appropriate. Inserting a tracheal tube into a patient under general anesthesia has the following main functions.

1. Respiratory tract protection: Tracheal intubation can effectively prevent vomitus, blood, secretions, etc. from entering the airway, avoid aspiration, respiratory tract obstruction, and reduce the occurrence of lung infections.

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2. Ventilation control: Mechanical ventilation can be used through the endotracheal tube to ensure adequate oxygenation and carbon dioxide removal of the patient under anesthesia and maintain the stability of vital signs.

3. Anesthetic drug delivery: After endotracheal intubation, anesthetic gas can be delivered through the respiratory system to deepen the anesthesia effect.

6. Why do patients need to undergo nebulization treatment after general anesthesia surgery?

First, during general anesthesia surgery, the humidity of the gas inhaled by the patient is low, causing the throat and airway to become dry, often resulting in dry cough, sore throat and other discomfort symptoms. Nebulizer therapy can humidify the patient's respiratory tract, reduce the dryness of the throat and airway, protect the respiratory mucosal barrier, and make every breath of the patient comfortable.

Secondly, adding drugs such as ambroxol hydrochloride and dexamethasone to the nebulizer can relieve airway hypersensitivity, promote sputum discharge, and ensure the patient's postoperative breathing safety.

Finally, some patients may reduce their activity and stay in bed for a long time due to pain after surgery, which may cause lung infection and atelectasis. Nebulizer therapy can promote the recovery of patients' lung function after surgery and reduce the incidence of complications such as lung infection and atelectasis.