Understanding Anesthesia Flashcards
4 A’s of Anesthesia
- Autonomic Stability
- Amnesia
- Akinesia
- Analgesia
Awareness
Unconsciousness; lack of memory
Amnesia
lack of memory of the event (procedure)
Analgesia
inability to feel pain
Akinesia
lack of movement (muscle relaxation)
Propofol
drug administered to cause relaxation and sleepiness before and during surgery or other medical procedures
Common muscle relaxant used in anesthesia
Succinylcholine
RSI
Rapid Sequence Induction: technique used to minimied the time between inducing anesthesia and securing an airway with a cuffed ET tube for patients with increased risk of aspiration
3 Phases of General Anesthesia
- Induction
- Maintenance
- Emergence
Induction
Phase of GA whereby the goal is to induce
unconsciousness in a fashion which is safe,
rapid and maintains hemodynamic stability.
Maintenance
phase of anesthesia involves the use of inhaled agents and intravenous medications to keep the patient asleep and stable during the procedure, achieving the 4 A’s and remaining hemodynamically stable throughout
Emergence
phase of anesthesia when the patient is waking up from anesthesia
Extubation
removal of a tube previously inserted into the trachea; or removal of an LMA
3 Criteria for Successful Extubation
- Patient can breathe on their own
- Patient has normal muscle strength (i.e. tongue doesn’t fall back)
- Patient is awake enough to obey commands
Intubation
process when an healthcare provider inserts a tube through a person’s mouth or nose, then into their trachea. The tube keeps the trachea open so that air can get through to ventilate the lungs; also, insertion of a supraglottic airway can be considered an intubation.
3 Commonly used inhaled agents during maintenance phase
- desflurane
- isoflurane
- sevoflurane
General Anesthesia
Anesthesia that acts on a patient so they are completely UNAWARE of any sensations throughout their body by making them unconscious
3 Anesthetic Techniques
- Regional
- Monitored Anesthetic Care
- General Anesthesia
Triad of Anesthesia
- Sleep hypnoses (Amnesia)
- Muscle relaxation (akinesia)
- Pain analgesia
ASA Classification Scale
degree of sickness of a patient, scale of 1-6
Monitored Anesthesia Care (MAC)
patients are not completely asleep; administration of various levels of sedations for minor procedures; typically there is no ET tube or LMA utilized; an oral/nasal airway could be used
Pulse Oximetry
measuring of the level of oxygen saturation of arterial blood
Anesthesia
a loss of feeling or awareness caused by drugs or other substances; keeps patients from feeling pain during surgery or other procedures
Positive Pressure Ventilation
pressure needed to inflate the lungs when under anesthesia
Difficult Airway
clinical situation in which a trained healthcare provider experiences difficulty with face mask ventilation of the upper airway, difficulty with tracheal intubation, or both
Frequency of Can’t intubate/Can’t Ventilate
1/10,000 cases
Indicators of a Difficult Airway (13)
- length of upper incisors
- Cormack-Lehane grades
- Overbite
- Small chin
- Interincisor distance less than 3 cm
- Mallampatti View
- Shape of palate
- TMJ
- Thyromental distance < 3 fingers length
- Length of neck
- Neck thickness
- Limited range of motion (head)
- Airway history
3 Key Points in 2022 ASA Difficult Airway Algorithm
- Optimize oxygenation
- Limit # attempts per device
- Be aware of the passage of time
Vagus Nerve
the nerve responsible for tasks such as heart rate, sweating, and muscle movements in the mouth, including speech
Factors that determine the type of airway device used
- ASA Classification
- Spontaneous breathing or controlled breathing
- Duration of the procedure
- Patient weight
- Reflux
- Patient Positioning
- Type of procedure
- Anesthesia provider experience
- Difficult airway
ASA 1
normal, healthy patient
ASA II
patient with mild systemic disease (i.e. smoker, social drinker, obesity)
ASA III
patient with severe systemic disease (i.e. poorly controlled diabetes, COPD, morbid obesity, etc)
ASA IV
patient with severe systemic disease that is a constant threat to life (i.e. MI, cardiac ischemia, sepsis, etc)
ASA V
moribund patient who is not expected to survive without the operation (i.e. abdominal aneurysm, massive trauma, etc)
ASA VI
declared brain-dead patient whose organs are being removed for donor purposes
GERD
chronic condition where acid regurgitates from the stomach into the esophagus.
Spontaneous Respiration (negative pressure)
movement of gas in and out of the lungs that is produced in response to an individual’s respiratory muscles. (natural breathing)
Controlled ventilation (positive pressure)
used to inflate the lungs of a patient when spontaneous breathing is inadequate or ceases entirely (apenea); pressure that is needed to blow up or inflate the lungs; the pressure needed to inflate the lungs is dependent on the elasticity of the lung
Most common cause of airway obstruction
tongue
Difficult airway
the clinical situation in which a conventionally trained anesthesiologist experiences difficulty with face mask ventilation of the upper airway, difficulty with tracheal intubation, or both
Mallampatti Views Class 1-4
