Types of anesthesia and sedation, for clinicians

This is the clinician view. It keeps every sentence of the plain guide and adds, for each section, the study design and citations of its sources, exact figures, and label wording quoted whole, marked For clinicians. Every added sentence is cited and checked like the rest. Back to plain language.

In short

Sedation is a continuum: from minimal sedation, where people respond normally, to general anesthesia, where they cannot be woken even by pain.E2Good¹
Under deep sedation and general anesthesia, breathing can be impaired and may need support.E2Good¹
Serious complications of spinal and epidural anesthesia are rare.E2Good²
In older adults having hip fracture surgery, spinal anesthesia was not better than general anesthesia for survival and walking at 60 days.E1Strong³

How sure each claim is:E1Strong E2Good Official text Review What the grades meanUnderlined words open a definition

The levels of sedation

The American Society of Anesthesiologists describes sedation and anesthesia as a continuum. Each level is defined by how a person responds and how well they breathe on their own.E2Good¹

The ASA continuum, in plain words
Level	What the ASA definition says
Minimal sedation	People respond normally to spoken commands. Thinking and coordination may be impaired, but airway reflexes, breathing and circulation are unaffected.E2Good¹
Moderate sedation (conscious sedation)	People respond purposefully to spoken commands, alone or with a light touch. No help is needed to keep the airway open, breathing is adequate, and circulation is usually maintained.E2Good⁴
Deep sedation	People cannot be easily woken but respond purposefully to repeated or painful stimulation. Breathing on their own may be impaired, and they may need help keeping the airway open.E2Good¹
General anesthesia	A drug-induced loss of consciousness in which people cannot be woken, even by painful stimulation. The ability to breathe independently is often impaired.E2Good¹

Sedation can become deeper than intended. For this reason, the ASA says whoever gives moderate sedation should be able to rescue a person who slips into deep sedation. Likewise, whoever gives deep sedation should be able to rescue a person who slips into general anesthesia.E2Good⁴

For clinicians

The ASA definitions, quoted as written, from minimal sedation to general anesthesia:

Minimal Sedation (Anxiolysis) is a drug-induced state during which patients respond normally to verbal commands. Although cognitive function and physical coordination may be impaired, airway reflexes, and ventilatory and cardiovascular functions are unaffected.
Moderate Sedation/Analgesia (“Conscious Sedation”) is a drug-induced depression of consciousness during which patients respond purposefully** to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained.
Deep Sedation/Analgesia is a drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully** following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate.
General Anesthesia is a drug-induced loss of consciousness during which patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired.
Quoted word for word from Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia E2Good^1,4

The ASA's rescue standard, quoted as written:

Individuals administering Moderate Sedation/Analgesia (“Conscious Sedation”) should be able to rescue*** patients who enter a state of Deep Sedation/Analgesia, while those administering Deep Sedation/Analgesia should be able to rescue*** patients who enter a state of General Anesthesia.
Quoted word for word from Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia E2Good⁴

The evidence in this section (2 sources)

Source	Design	Grade	Citations (NIH iCite)
1 American Society of Anesthesiologists, 2024	Guideline	E2Good	Not tracked
4 American Society of Anesthesiologists, 2024	Guideline	E2Good	Not tracked

What is monitored anesthesia care (MAC)?

The ASA explains that monitored anesthesia care is not a level on the continuum. It is a specific anesthesia service performed by a qualified anesthesia provider for a diagnostic or therapeutic procedure.E2Good⁴

The propofol label lists starting and maintaining MAC sedation in adults among its uses. It says that for general anesthesia or MAC sedation it should be given only by people trained in general anesthesia who are not doing the procedure.Official text⁵

A study of malpractice claims found that oversedation leading to slowed breathing was an important cause of injury during MAC. It also found that monitoring, vigilance and early resuscitation could have prevented many of these injuries.E2Good⁶

More than 40% of the MAC claims involved death or permanent brain damage, similar to claims for general anesthesia.E2Good⁶

For clinicians

The ASA's distinction, quoted as written:

Monitored Anesthesia Care (“MAC”) does not describe the continuum of depth of sedation, rather it describes “a specific anesthesia service performed by a qualified anesthesia provider, for a diagnostic or therapeutic procedure.”
Quoted word for word from Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia E2Good⁴

The propofol label on who administers it, quoted as written:

For general anesthesia or monitored anesthesia care (MAC) sedation, DIPRIVAN should be administered only by persons trained in the administration of general anesthesia and not involved in the conduct of the surgical/diagnostic procedure.
Quoted word for word from DIPRIVAN (propofol) injectable emulsion, Prescribing Information Official text⁵

The evidence in this section (3 sources)

Source	Design	Grade	Citations (NIH iCite)
4 American Society of Anesthesiologists, 2024	Guideline	E2Good	Not tracked
5 Fresenius Kabi USA, LLC, 2025	FDA label	Official text	Not tracked
6 Bhananker SM, Anesthesiology, 2006	Observational study	E2Good	237 (RCR 10.21)

Spinal, epidural and nerve block anesthesia

An epidural is a central nerve block: local anesthetic is injected close to the nerves that carry pain.E1Strong⁷

Spinal and epidural anesthesia together are called neuraxial blockade. An overview of randomized trials found overall deaths about a third lower in patients assigned to neuraxial blockade.E1Strong⁸

The authors said the size of some of these benefits is uncertain. They said more research is needed to know whether they come from the block itself or partly from avoiding general anesthesia.E1Strong⁸

In the REGAIN trial of older adults having hip fracture surgery, spinal anesthesia was not superior to general anesthesia for survival and walking at 60 days. Delirium rates were similar.E1Strong³

A UK national audit found serious complications of spinal and epidural anesthesia rare. Permanent injury was estimated at 2.0 to 4.2 per 100,000 cases, and two thirds of initially disabling injuries resolved fully.E2Good²

A review estimated neurological complications after spinal or epidural blocks at under 0.04%. It estimated nerve symptoms after peripheral nerve blocks at under 3%, with permanent injury rare.Review⁹

For clinicians

Rodgers' overview of randomized trials recorded 103 deaths among 4871 patients allocated to neuraxial blockade against 144 among 4688 (odds ratio 0.70, 95% CI 0.54 to 0.90, P=0.006).E1Strong⁸

NAP3 expressed the incidence of permanent injury from central neuraxial block per 100,000 cases as 4.2 (95% CI 2.9 to 6.1) on a pessimistic reading and 2.0 (1.1 to 3.3) on an optimistic one. Many major complications resolved within 6 months.E2Good²

Brull's review put neurological complications after central neuraxial blockade below 4 per 10,000 (0.04%) and neuropathy after peripheral nerve block below 3 per 100 (3%).Review⁹

In the Cochrane review of labor epidurals, women with an epidural had more hypotension, motor blockade, fever and urinary retention.E1Strong⁷

Low-quality evidence in that review showed epidurals may give better pain relief and maternal satisfaction than non-epidural methods. Epidurals had no impact on cesarean section or long-term backache, and no apparent immediate effect on Apgar scores or neonatal intensive care admission.E1Strong⁷

The evidence in this section (5 sources)

Source	Design	Grade	Citations (NIH iCite)
7 Anim-Somuah M, Cochrane Database Syst Rev, 2018	Systematic review	E1Strong	Not tracked
8 Rodgers A, BMJ, 2000	Meta-analysis	E1Strong	1,332 (RCR 50.1)
3 Neuman MD, N Engl J Med, 2021	Randomized trial	E1Strong	372 (RCR 34.2)
2 Cook TM, Br J Anaesth, 2009	Observational study	E2Good	550 (RCR 23.92)
9 Brull R, Anesth Analg, 2007	Expert review	Review	413 (RCR 17.54)

Who gives anesthesia?

The propofol label covers who gives it for general anesthesia or MAC sedation. It states it should be given only by people trained in general anesthesia who are not involved in the procedure itself. The sevoflurane label says the same for that gas.Official text^5,10

For clinicians

The sevoflurane label, quoted as written:

ULTANE is indicated for induction and maintenance of general anesthesia in adult and pediatric patients for inpatient and outpatient surgery. ULTANE should be administered only by persons trained in the administration of general anesthesia.
Quoted word for word from ULTANE (sevoflurane) volatile liquid for inhalation, Prescribing Information Official text¹⁰

The evidence in this section (2 sources)

Source	Design	Grade	Citations (NIH iCite)
5 Fresenius Kabi USA, LLC, 2025	FDA label	Official text	Not tracked
10 AbbVie Inc., 2025	FDA label	Official text	Not tracked

What is not known yet

Whether the benefits seen with neuraxial anesthesia come from the block itself or partly from avoiding general anesthesia is still uncertain.E1Strong⁸

Questions you might bring to your anesthesia team

What type and depth of anesthesia is planned, and why?
Who will give the anesthesia, and who will watch my breathing throughout?
Is a spinal, epidural or nerve block an option for this procedure?
What are the common side effects and the rare serious risks of the plan?

Every claim in this guide was written from its sources and checked against them word for word. Its clinical review by Dr. Recio, a practicing nurse anesthesiologist (CRNA), is pending. This line changes when the review is done.

Sources

Each source opens on PubMed, DailyMed or the publisher's page. Under each one are the exact words from it that this page relies on, copied word for word and checked against the original.

Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia. American Society of Anesthesiologists, 2024. E2Good Guideline
The words this page rests on
Minimal Sedation (Anxiolysis) is a drug-induced state during which patients respond normally to verbal commands. Although cognitive function and physical coordination may be impaired, airway reflexes, and ventilatory and cardiovascular functions are unaffected.
General Anesthesia is a drug-induced loss of consciousness during which patients are not arousable, even by painful stimulation. The ability to independently maintain ventilatory function is often impaired.
Deep Sedation/Analgesia is a drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully** following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate.
Major complications of central neuraxial block: report on the Third National Audit Project of the Royal College of Anaesthetists. Cook TM, Br J Anaesth, 2009. E2Good Observational studyPMID 19139027; DOI 10.1093/bja/aen360; cited 550 times, relative citation ratio 23.92 (NIH iCite, 2026-10-18)
The words this page rests on
Serious complications of central neuraxial block (CNB) are rare.
The incidence of permanent injury due to CNB (expressed per 100,000 cases) was 'pessimistically' 4.2 (95% confidence interval 2.9-6.1) and 'optimistically' 2.0 (1.1-3.3).
Two-thirds of initially disabling injuries resolved fully. The data are reassuring and suggest that CNB has a low incidence of major complications, many of which resolve within 6 months.
Spinal Anesthesia or General Anesthesia for Hip Surgery in Older Adults. Neuman MD, N Engl J Med, 2021. E1Strong Randomized trialPMID 34623788; DOI 10.1056/NEJMoa2113514; cited 372 times, relative citation ratio 34.2 (NIH iCite, 2026-10-18)
The words this page rests on
Spinal anesthesia for hip-fracture surgery in older adults was not superior to general anesthesia with respect to survival and recovery of ambulation at 60 days. The incidence of postoperative delirium was similar with the two types of anesthesia.
Statement on Continuum of Depth of Sedation: Definition of General Anesthesia and Levels of Sedation/Analgesia. American Society of Anesthesiologists, 2024. E2Good Guideline
The words this page rests on
Moderate Sedation/Analgesia (“Conscious Sedation”) is a drug-induced depression of consciousness during which patients respond purposefully** to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained.
Individuals administering Moderate Sedation/Analgesia (“Conscious Sedation”) should be able to rescue*** patients who enter a state of Deep Sedation/Analgesia, while those administering Deep Sedation/Analgesia should be able to rescue*** patients who enter a state of General Anesthesia.
Monitored Anesthesia Care (“MAC”) does not describe the continuum of depth of sedation, rather it describes “a specific anesthesia service performed by a qualified anesthesia provider, for a diagnostic or therapeutic procedure.”
DIPRIVAN (propofol) injectable emulsion, Prescribing Information. Fresenius Kabi USA, LLC, 2025. Official text FDA label
The words this page rests on
DIPRIVAN is an intravenous general anesthetic and sedation drug indicated for: (1) • Induction of General Anesthesia for Patients Greater than or Equal to 3 Years of Age • Maintenance of General Anesthesia for Patients Greater than or Equal to 2 Months of Age • Initiation and Maintenance of Monitored Anesthesia Care (MAC) Sedation in Adult Patients • Sedation for Adult Patients in Combination with Regional Anesthesia • Intensive Care Unit (ICU) Sedation of Intubated, Mechanically Ventilated Adult Patients
For general anesthesia or monitored anesthesia care (MAC) sedation, DIPRIVAN should be administered only by persons trained in the administration of general anesthesia and not involved in the conduct of the surgical/diagnostic procedure.
Injury and liability associated with monitored anesthesia care: a closed claims analysis. Bhananker SM, Anesthesiology, 2006. E2Good Observational studyPMID 16436839; DOI 10.1097/00000542-200602000-00005; cited 237 times, relative citation ratio 10.21 (NIH iCite, 2026-10-18)
The words this page rests on
Oversedation leading to respiratory depression was an important mechanism of patient injuries during MAC. Appropriate use of monitoring, vigilance, and early resuscitation could have prevented many of these injuries.
More than 40% of claims associated with MAC involved death or permanent brain damage, similar to general anesthesia claims.
Epidural versus non-epidural or no analgesia for pain management in labour. Anim-Somuah M, Cochrane Database Syst Rev, 2018. E1Strong Systematic reviewPMID 29781504
The words this page rests on
Epidural analgesia is a central nerve block technique achieved by injection of a local anaesthetic close to the nerves that transmit pain, and is widely used as a form of pain relief in labour.
Women with epidural experienced more hypotension, motor blockade, fever, and urinary retention.
Low-quality evidence shows that epidural analgesia may be more effective in reducing pain during labour and increasing maternal satisfaction with pain relief than non-epidural methods.
Epidural analgesia had no impact on the risk of caesarean section or long-term backache, and did not appear to have an immediate effect on neonatal status as determined by Apgar scores or in admissions to neonatal intensive care.
Reduction of postoperative mortality and morbidity with epidural or spinal anaesthesia: results from overview of randomised trials. Rodgers A, BMJ, 2000. E1Strong Meta-analysisPMID 11118174; DOI 10.1136/bmj.321.7275.1493; cited 1,332 times, relative citation ratio 50.1 (NIH iCite, 2026-10-18)
The words this page rests on
Overall mortality was reduced by about a third in patients allocated to neuraxial blockade (103 deaths/4871 patients versus 144/4688 patients, odds ratio=0.70, 95% confidence interval 0.54 to 0.90, P=0. 006).
Neuraxial blockade reduces postoperative mortality and other serious complications. The size of some of these benefits remains uncertain, and further research is required to determine whether these effects are due solely to benefits of neuraxial blockade or partly to avoidance of general anaesthesia.
Neurological complications after regional anesthesia: contemporary estimates of risk. Brull R, Anesth Analg, 2007. Review Expert reviewPMID 17377115; DOI 10.1213/01.ane.0000258740.17193.ec; cited 413 times, relative citation ratio 17.54 (NIH iCite, 2026-10-18)
The words this page rests on
Our review suggests that the rate of neurological complications after central nerve blockade is <4:10,000, or 0.04%. The rate of neuropathy after PNB is <3:100, or 3%. However, permanent neurological injury after RA is rare in contemporary anesthetic practice.
ULTANE (sevoflurane) volatile liquid for inhalation, Prescribing Information. AbbVie Inc., 2025. Official text FDA label
The words this page rests on
ULTANE is indicated for induction and maintenance of general anesthesia in adult and pediatric patients for inpatient and outpatient surgery. ULTANE should be administered only by persons trained in the administration of general anesthesia.

NextTIVA or inhaled anesthesia RelatedTIVA or inhaled anesthesia Before the visitPrint the questions for your anesthesia team

With general anesthesia, you will be unconscious and unaware of anything that happens during your procedure.
While the anesthesia is working and you are unconscious, many of your body’s functions will slow down or need help to work effectively. A tube may be placed in your throat to help you breathe.

Minimal Sedation (Anxiolysis) is a drug-induced state during which patients respond normally to verbal commands. Although cognitive function and physical coordination may be impaired, airway reflexes, and ventilatory and cardiovascular functions are unaffected.

Depending on the procedure, the level of sedation may range from minimal (you’ll feel drowsy but able to talk) to deep (you probably won’t remember the procedure). Moderate or deep sedation may slow your breathing, and in some cases, you may be given oxygen.
But even with deep sedation, you won’t be unconscious, as you would be with general anesthesia.

Deep Sedation/Analgesia is a drug-induced depression of consciousness during which patients cannot be easily aroused but respond purposefully** following repeated or painful stimulation. The ability to independently maintain ventilatory function may be impaired. Patients may require assistance in maintaining a patent airway, and spontaneous ventilation may be inadequate.

If you choose to have an epidural, an anesthesiologist will insert a needle and a tiny tube, called a catheter, in the lower part of your back. The needle is removed and the catheter left in place for delivery of the medication through the tube as needed.
An epidural provides anesthesia that creates a band of numbness from your bellybutton to your upper legs. It allows you to be awake and alert throughout labor, as well as to feel pressure.

A spinal block, like an epidural, involves an injection in the lower back. While you sit or lie on your side in bed, a small amount of medication is injected into the spinal fluid to numb the lower half of the body. It brings good relief from pain and starts working quickly, but it lasts only an hour or two and is usually given only once during labor.
Spinal analgesia is stronger and is used during procedures such as cesarean deliveries, also known as C-sections, and knee and hip replacements.

Moderate Sedation/Analgesia (“Conscious Sedation”) is a drug-induced depression of consciousness during which patients respond purposefully** to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate. Cardiovascular function is usually maintained.

Monitored Anesthesia Care (“MAC”) does not describe the continuum of depth of sedation, rather it describes “a specific anesthesia service performed by a qualified anesthesia provider, for a diagnostic or therapeutic procedure.”

DIPRIVAN is an intravenous general anesthetic and sedation drug indicated for: (1) • Induction of General Anesthesia for Patients Greater than or Equal to 3 Years of Age • Maintenance of General Anesthesia for Patients Greater than or Equal to 2 Months of Age • Initiation and Maintenance of Monitored Anesthesia Care (MAC) Sedation in Adult Patients • Sedation for Adult Patients in Combination with Regional Anesthesia • Intensive Care Unit (ICU) Sedation of Intubated, Mechanically Ventilated Adult Patients

Local anesthesia, also called local anesthetic, is usually a one-time injection of medicine that numbs a small area of the body. It is used for procedures such as performing a skin biopsy or breast biopsy, repairing a broken bone, or stitching a deep cut. You will be awake and alert, and you may feel some pressure, but you won’t feel pain in the area being treated.

Other types of nerve blocks are used to help control pain after certain orthopedic procedures, such as shoulder, knee, and ankle surgeries. Nerve blocks can also be used to help manage chronic pain. Anesthetic medication is injected near a nerve or group of nerves to numb them for hours, and sometimes days, to reduce pain.