Different Types of Anaesthesia: Anaesthetist Nurse Guide

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.

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

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

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.

 * 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