Anaesthesia was one of the most important medical developments of the nineteenth century, making complex surgery possible. More than 150 years on, anaesthesia is its own clinical specialty with high safety standards and very low risk — when done properly. This article explains the types of anaesthesia and the standards of care patients should know.
Anaesthesia is its own specialty
Anaesthesiology and critical care is a post-graduate medical specialty. Training covers the pharmacology of anaesthetic agents, respiratory and cardiovascular physiology under anaesthesia, intra- and post-operative emergency management, and pain management. In Vietnam this specialty requires post-MD training (Specialty I: 2 years, Specialty II: a further 2 years).
This means: the surgeon is NOT the anaesthetist. For general-anaesthesia cases, a separate board-certified anaesthesiologist must be present — this is a non-negotiable standard in safe surgery.
Types of anaesthesia
Local anaesthesia
Anaesthetic (lidocaine, bupivacaine) is injected at the operative site, numbing the area. The patient is fully awake. Suited to short, small operations: filler / toxin injection, some small eyelid procedures, some small scar revisions.
Monitored anaesthesia care (MAC) — local with sedation
Local anaesthesia plus IV sedation so the patient is relaxed and sometimes lightly asleep. The patient breathes spontaneously without an endotracheal tube. Suited to mid-range procedures: small-volume liposuction, some eyelid surgery, some smaller nasal procedures. Requires a continuous anaesthesia provider.
General anaesthesia
The patient is fully unconscious throughout. An endotracheal tube or supraglottic airway is used to support ventilation. This is the anaesthesia for most major plastic-surgery procedures: breast augmentation, abdominoplasty, structural rhinoplasty, facelift. Requires a board-certified anaesthesiologist present continuously.
Regional anaesthesia
A whole body region is anaesthetised (for example a brachial plexus block for arm surgery). Less common in major plastic surgery, but may be added for post-operative pain control.
Monitoring equipment
An internationally compliant operating theatre uses continuous monitoring:
- ECG — continuous cardiac monitoring.
- Blood pressure — measured every few minutes.
- SpO2 — pulse oximetry for blood oxygen.
- EtCO2 — end-tidal CO2, a sensitive measure of ventilation.
- Temperature — to prevent hypothermia.
- BIS (Bispectral Index) — depth of anaesthesia, helping avoid intra-operative awareness and over-anaesthesia.
An operating theatre missing any of these — particularly for general anaesthesia — does not meet the safety standard. Ask the facility about specific equipment.
Meeting the anaesthesiologist before surgery
The pre-operative anaesthesia visit is an important safety standard. In this visit:
- The anaesthesiologist conducts a general health assessment focusing on cardiac and respiratory status.
- Airway is assessed to anticipate intubation conditions.
- Medical history, current medications, and allergies are reviewed.
- Previous anaesthesia history (including any events) is discussed.
- The anaesthesia plan and post-operative pain plan are formulated.
- The patient signs anaesthesia consent — a separate document from surgical consent.
The pre-anaesthesia visit typically occurs before the day of surgery — not on the morning of surgery. It is an opportunity for the patient to ask questions and build trust with the anaesthesiologist.
Risks of anaesthesia
Modern anaesthesia is safe but not risk-free:
- Post-operative nausea and vomiting: common (20–30%), usually mild and controllable with medication.
- Sore throat from intubation: mild, resolves in 1–2 days.
- Allergic reaction to anaesthetic agents: rare.
- Drowsiness and fatigue: normal, resolves in 1–3 days.
- Intra-operative awareness: very rare with modern anaesthesia and BIS monitoring.
- Major cardiovascular events: very rare in healthy patients, higher in patients with uncontrolled comorbidity.
- Death: very rare — international literature reports roughly 1 in 200,000 for healthy patients.
Individual factors that affect anaesthesia
Several factors need careful assessment:
- Age: > 65 raises cardiovascular risk and slows recovery.
- BMI: obesity (BMI > 35) raises airway and respiratory risk.
- Cardiac disease: cardiac assessment is needed pre-operatively.
- Asthma and COPD: should be stably controlled before surgery.
- Obstructive sleep apnea: raises post-operative respiratory risk.
- Smoking: raises respiratory and wound-healing risk.
- Prior anaesthetic events: must be disclosed and evaluated in detail.
In consultation, patients tend to ask many questions about surgery and few about anaesthesia. This is a misjudgement. In many cases the most serious adverse events occur in the anaesthetic phase — not the surgical phase. A good anaesthesiologist and a properly equipped operating theatre are most of your safety insurance.
Frequently asked questions
I am afraid of waking up during surgery — can this happen?
Intra-operative awareness is very rare in modern anaesthesia with BIS monitoring. The literature reports roughly 1–2 per 1,000 without BIS and much lower with BIS. Facilities that use BIS for prolonged general anaesthesia substantially reduce this risk.
Will I have long-term "memory loss" after anaesthesia?
No. Modern anaesthesia does not cause long-term memory loss in most patients. Some older patients can experience temporary post-operative cognitive dysfunction (POCD) — lasting weeks to months — particularly after major surgery. This has been studied extensively and most patients recover fully.
Do I need pre-operative tests?
Yes, depending on health status and procedure. Most cases: complete blood count, coagulation, blood sugar, liver and kidney function, ECG. Older patients or those with comorbidities may need additional tests. The anaesthesiologist orders these at the pre-operative visit.
Can I take my usual medications on the morning of surgery?
It depends on the medication. Cardiac and antihypertensive medications are usually continued (taken with a small sip of water). Diabetes medications and anticoagulants need specific adjustment — the anaesthesiologist will guide you in detail at the pre-operative visit. Never decide to hold or continue medications without discussion.
I have had an anaesthetic event before — can I still have surgery?
It depends on the event. A severe allergic reaction (anaphylaxis) to a specific agent means avoiding that agent — alternatives exist. Malignant hyperthermia is a rare genetic condition that needs specific precautions but is not a contraindication. Each history requires individual evaluation — share the detail at the pre-anaesthesia visit.