Two or three things you should know about anesthesia

This is the 4861st article of Da Yi Xiao Hu

With the development of science and technology and society, more and more people choose more comfortable ways in medical diagnosis and treatment, which makes "anesthesia" a medical method more widely used in ordinary people's lives. In the past, the public's impression of anesthesia only existed in the operating room, shrouded in a mysterious coat. Although anesthesiologists have popularized science in recent years, there are still confusions and misunderstandings. Today, we will solve several common problems for you.

What issues should be paid attention to during anesthesia endoscopy?

Painless gastroenteroscopy usually uses general anesthesia to reduce or eliminate the pain and anxiety during endoscopic diagnosis and treatment, and improve the safety and comfort of the examination.

1. Preparations before anesthesia

Anesthesia assessment : The doctor at the anesthesia assessment clinic needs to understand the patient's medical history (surgical history, allergy history, medication use), recent illness (such as upper respiratory tract infection), current physical condition, check the results of preoperative examinations (such as electrocardiogram, blood routine, liver function, etc.), and assess the patient's physical condition.

Anesthesia preparation : In addition to the necessary dietary preparation and fasting for gastrointestinal endoscopy, in order to avoid reflux of liquid in the digestive tract during anesthesia and cause aspiration, patients undergoing anesthesia are also required to stop drinking water three hours before anesthesia.

2. Precautions after anesthesia

After waking up from anesthesia, the examinee may feel mild dizziness, fatigue and other discomforts, which is normal and can be relieved after a short rest. Drinking water and eating can be allowed 2 hours after waking up from anesthesia, starting with a small amount of water and liquids, and gradually transitioning to a normal diet. If you feel any discomfort, you need to postpone eating.

3. Are there any risks with endoscopic anesthesia?

Endoscopic anesthesia techniques are generally considered safe and effective, but there are still some potential risks, such as

Drug allergy : Some patients may be allergic to certain anesthetic drugs and may experience rash, shortness of breath, increased heart rate, etc. Therefore, it is important to understand the allergy history during the preoperative evaluation.

Respiratory depression : General anesthesia will weaken the subject's respiratory movements, which may lead to hypoxia or carbon dioxide retention and respiratory depression, but the duration is very short. With oxygen inhalation and the monitoring and assistance of an anesthesiologist, it can be quickly corrected, so there is no need to worry too much.

Risk of suffocation : Under general anesthesia, the patient's throat reflex will be weakened, which may cause vomitus to enter the respiratory tract and cause aspiration, leading to the risk of suffocation. In addition, operations such as endotracheal intubation may also increase the risk of suffocation. If it occurs, the anesthesiologist will correct it in time and provide help to aspirate the aspirated material.

Others : such as cardiovascular and cerebrovascular accidents, delayed postoperative recovery, drug interactions, etc.

4. Patients who are not suitable for endoscopic general anesthesia

(1) History of allergy to anesthetic drugs

(2) Severe cardiovascular and respiratory diseases, and recent upper respiratory tract infection

(3) Poor basic condition, such as advanced age, physical weakness, or multiple diseases

(4) Presence of sleep apnea syndrome

(5) For obese patients, excessive weight will affect breathing and increase the risk of anesthesia.

2. Can breastfeeding mothers undergo anesthesia?

Many new mothers and fathers are worried about the impact of anesthesia on breastfeeding. On the one hand, they are afraid of the pain of medical examinations and treatments without anesthesia, and on the other hand, they are worried that breast milk will have a negative impact on the baby after anesthesia. Should they endure the pain for the safety of the baby? Will anesthesia affect breastfeeding?

The drugs involved in the anesthesia method determine whether it will affect breast milk. Currently, anesthesia methods can be roughly divided into two types: local anesthesia and general anesthesia.

Local anesthesia includes spinal anesthesia, nerve block, local infiltration anesthesia and surface anesthesia, etc. Local anesthetic drugs are injected into the corresponding parts to block the conduction of nerve signals, so that a certain area of ​​the body temporarily loses sensation. The anesthesia range is limited to a part of the body, and the drugs used are easily absorbed into breast milk. However, because they are mostly used locally, the drug dosage itself is small, and the amount that can enter breast milk and be absorbed by the baby is negligible, and will not have any effect.

There are many drugs involved in general anesthesia, and the drugs will diffuse from the mother's plasma into breast milk. However, the intravenous anesthetics commonly used for gastrointestinal endoscopy are quick to take effect and metabolized quickly. They are not easy to enter breast milk, and the amount absorbed by the baby orally is very low, causing almost no harm. Another type of anesthetic, inhaled anesthetics, are also metabolized quickly and cleared from the body very quickly, and are almost not absorbed by the baby. Analgesics are also needed in anesthesia. The most common are opioids. Among them, sufentanil and remifentanil are the most commonly used for intraoperative and postoperative analgesia. Long-term studies have shown that they can be used for breastfeeding women; but other analgesics, such as pethidine, tramadol and codeine, are considered not recommended for use by breastfeeding mothers because they may be absorbed by the baby through breast milk and cause respiratory depression.

All anesthesiologists have received relevant training, so breastfeeding mothers need to communicate with their anesthesiologists before anesthesia and tell them that they are feeding their babies. The anesthesiologists will make corresponding adjustments to protect the baby and the mother.

3. Can I take medicine before anesthesia?

For patients who have undergone surgical anesthesia, the most common reminder they hear from nurses the night before surgery is "Remember not to eat or drink!" But some patients are taking long-term medications and will ask, "Doctor, should I still take this medicine?"

This needs to be determined based on the patient's specific circumstances.

1. Drugs that require a longer discontinuation period

1. Noradrenergic nerve blockers - reserpine (including compound reserpine such as Beijing Antihypertensive No. 0) can easily cause severe hypotension and slow heart rate, which is particularly obvious during spinal anesthesia. If hypotension or heavy bleeding occurs during surgery, even if pressor drugs are injected intravenously, the pressor effect is not obvious.

2 Monoamine oxidase inhibitors - phenelzine, bromofaromine, toloxatone, isocarboxazid, phenylcypromine

2. Drugs that should be discontinued on the morning of surgery

1 Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB) - valsartan (Diovan), irbesartan (Ambroxol), captopril (Captopril), benazepril (Lotensin). Hypertensive patients are prone to hypotension during surgery, which may aggravate surgery-related fluid loss and increase the risk of hypotension during surgery.

2 Diuretics - hydrochlorothiazide (Dixam), furosemide (Lasix), spironolactone (Spironolactone), may cause electrolyte imbalance and insufficient effective circulating blood volume. Stop taking them on the morning of surgery (except for patients with chronic heart failure)

3 Oral hypoglycemic drugs - metformin, pioglitazone, glibenclamide, rosiglitazone, etc.

3. Drugs that do not need to be discontinued

1 Calcium channel blockers (CCB) - nifedipine (Nifedipine), amlodipine (Amlodipine), verapamil (Isopamine)

1 β-blockers - metoprolol (Betaloc), bisoprolol (Conxin)

1 Nitrates - nitroglycerin, isosorbide (isosorbide)

2 Antiarrhythmic drugs - amiodarone (Cordarone), digoxin (Clari), quinidine, and beta-blockers.

3 Statins – Atorvastatin (Lipitor), Simvastatin (Zocor), Pravastatin

4 Antipsychotics – Haloperidol, Risperidone, Olanzapine

5 Anti-Parkinson's drugs - Levodopa, etc.

(IV) Drugs taken during surgery but with adjusted dosage on the same day

1 Anti-epileptic drugs - phenytoin sodium, carbamazepine

(V) Whether to stop medication and how long to stop medication should be determined based on the type of surgery and the patient's condition

1. Antiplatelet drugs: aspirin (Bay Aspirin), clopidogrel (Plavix), ticagrelor (Brilinda)

2 Anticoagulants - warfarin (warfarin sodium tablets), rivaroxaban (Xarelto), dabigatran (Prabiquinol), unfractionated heparin and low molecular weight heparin

The above are answers to some common questions about anesthesia. I hope today’s introduction can help everyone live a healthy life.

Author: Minhang Hospital Affiliated to Fudan University

Department of Anesthesiology