Question 1: What are the three types of anesthesia?

There are three different types of anesthesia:1

  • Local – involves the administration of local anesthetic to a small area being operated on. Via injection, topical or spray.
  • Regional – provides analgesia over a specific body area, like the legs or an arm. This includes epidural, spinal or nerve infiltrations.
  • General – produces unconsciousness, body relaxation and loss of sensation. Medication is administered via inhalation or IV. Airway and breathing need to be supported.

Question 2: What’s the difference between sedation and anesthesia?

Sedation is a continuum that ranges from a state of minimal sedation to a deeper state. As the continuum progresses, patient responsiveness, airway, ventilation and cardiovascular function become increasingly compromised.2 At the end of this continuum, it’s general anesthesia where the patient has lost consciousness, does not respond to painful stimulation, airway and breathing must be supported and cardiovascular function may be impaired.2

Because sedation is a continuum, it is not always possible to predict how an individual patient will respond.2 Therefore, practitioners intending to produce a given level of sedation, should be able to rescue patients whose level of sedation becomes deeper than initially intended.2

Question 3: What medication is used in sedation practice?

Different medications are used in sedation practice. Benzodiazepines, like midazolam are used for its anxiolytic effect, allowing patients to be relaxed and comfortable during procedures.3 

Opioids, like fentanyl are used to manage interventional pain, making sure the patient is pain free throughout the procedure.3

When administering opioids and benzodiazepines, we need to account for synergistic effects and be mindful that a reduced dose of each medication will be necessary to reach the desired sedation level.3 For this reason, we always administer opioids first and always titrate drugs to effect.*

During sedation, the patient will be able to respond purposefully and will be aware but may not recall periods of the intervention due to the effects of medication.2

Question 4: What complications can occur in sedation and anesthesia? 

Airway obstruction and inadequate ventilation are two common complications that may occur as a result of the sedative drugs.4 It’s important to keep monitoring the patient’s clinical status, make sure the airway is patent, that ventilation depth and frequency are adequate, and intervene as soon as possible when required.4

Over sedation can happen, even if professionals are careful with administration and titrate-to-effect.5 This is because there is always a certain degree of patient variability in sedation. 5  When the patient becomes over-sedated, the airway and breathing may be compromised. 5

To accurately administer the right dose of opioids that is solely based on the pain intensity, we recommend using the NOL® Monitor.* It’s been proven that the NOL® guided opioid administration is associated with a 30% reduction in intraoperative opioid usage (remifentanil).6

Paradoxical agitation can also occur, particularly with the administration of midazolam.7 The patient will become very agitated, try to climb off the table, but will not be aware. It’s important to stop the procedure, reassure and calm the patient.

Regurgitation and aspiration are also possible but rare risks which can occur.4,8

Patients need to be pre-assessed so we can identify possible risks and minimize these complications.4

Question 5: How do you make sure the patient is safe during sedation?

Practicing sedation is an advanced role. Keeping the patient safe starts way before the patient is on the operating table.

  1. Nurses need to have specific training to make sure we have the right knowledge and skills.4 
  2. Patients need to be pre-assessed, so we identify possible risks.4
  3. The environment needs to be prepared, including staff, equipment and medication.
  4. Monitor the level of consciousness and nociceptive (pain) state to guide your administration of medication, and carefully observe the patient’s response to the medication.3
  5. Using adequate equipment to monitor the clinical status. Capnography is a very important tool which gives us insight into the patients’ breathing.9 It’s the quickest equipment to inform us of respiratory compromise.10 We also use pulse oximetry, ECG and blood pressure monitoring. We interpret the information provided by the equipment, observe the patient and make clinical decisions.

About the author

My name is Andreia Trigo RN BSc MSc, I am a nurse consultant with over a decade of experience in anaesthesia, sedation and pain management.

This involves patient care, as well as lecturing at post grad level on these topics, presenting at conferences and co-developing a very successful sedation course at SedateUK. My passion for creating safer environments for patients and professionals led me to collaborate with Medtronic and share my knowledge and expertise with our professional community.


 * The content of this article is meant for general educational purposes only. Unless cited, the contents and conclusions of the presentation are solely those of the presenter and do not necessarily represent the views of Medtronic

  • 1. Australian Society of Anaesthesists. 2022. Types of anaesthesia. Available at:

  • 2. American Society of Anaesthesiologists. 2019. Depth of Anasthesia. Available at:

  • 3. Urman R & Kaye AD. 2012. Moderate and deep sedation in clinical practice. Cambridge University Press. doi : 10.1017/cbo9781139084000.005

  • 4. Becker DE, Haas DA. 2011. Recognition and management of complications during moderate and deep sedation part 1: respiratory considerations. Anesth Prog. 58(2):82-92. doi: 10.2344/0003-3006-58.2.82.

  • 5. Garrett J, Vanston A, Ogola G, da Graca B, Cassity C, Kouznetsova MA, Hall LR, Qiu T. 2021. Predicting opioid-induced oversedation in hospitalised patients: a multicentre observational study. BMJ Open. 2021 Nov 24;11(11):e051663. doi: 10.1136/bmjopen-2021-051663.

  • 6. Meijer FS, Martini CH, Broens S, Boon M, Niesters M, Aarts L, Olofsen E, van Velzen M, Dahan A. Nociception-guided versus Standard Care during Remifentanil-Propofol Anesthesia: A Randomized Controlled Trial. Anesthesiology. 2019 May;130(5):745-755. doi: 10.1097/ALN.0000000000002634

  • 7. Cabrera LS, Santana AS, Robaina PE, Palacios MS. 2010. Paradoxical reaction to midazolam reversed with flumazenil. J Emerg Trauma Shock. 3(3):307. doi: 10.4103/0974-2700.66551.

  • 8. Hårdemark Cedborg AI, Sundman E, … Eriksson LI. 2015. Effects of Morphine and Midazolam on Pharyngeal Function, Airway Protection, and Coordination of Breathing and Swallowing in Healthy Adults. Anesthesiology. 122:1253–1267 doi:

  • 9. Krauss B, Hess DR. 2007. Capnography for procedural sedation and analgesia in the emergency department. Ann Emerg Med. 50(2):172-81. doi: 10.1016/j.annemergmed.2006.10.016.

  • 10. Burton JH, Harrah JD, Germann CA, Dillon DC. 2006. Does end-tidal carbon dioxide monitoring detect respiratory events prior to current sedation monitoring practices? Acad Emerg Med. (5):500-4. doi: 10.1197/j.aem.2005.12.017.