1. Chapter 15 General Anesthesia
Elsevier items and derived items © 2006 by Saunders, an imprint of Elsevier Inc.

2. Objective 1 Define terminology related to anesthesia. Amnestic
Agent that causes memory impairment
Depolarization
Reversal of charges at a cell membrane, caused by a rapid inflow of sodium ions

3. Objective 1. Terms Emulsion Endotracheal (ET) tube Extubation
A mixture of two liquids not mutually soluble
Endotracheal (ET) tube
An airway catheter inserted in the trachea to assure patency of the upper airway and provide ventilation
Extubation
Process of removing a previously inserted endotracheal tube

4. Objective 1. Terms Intubation LMA Opioid Repolarization
Insertion of an endotracheal tube
LMA
Laryngeal masked airway; an airway that is placed over the larynx
Opioid
Any synthetic narcotic not derived from opium
Repolarization
Restoration of the polarized state at the cell membrane

5. Review basics of anesthesia
Review pain impulses
Nerve endings
Nerves
Sensory and motor
Spinal cord
Brain

6. Review of process of pain
Nerve endings stimulated
Transmit via sensory nerve
To spinal cord (motor loop)
To brain for interpretation and response

7. Objective 2
Discuss indications for general anesthesia.

8. Objective 2. Indications
The surgical procedure to be performed
Multiple sites
Need for motionless field
Long duration

9. Objective 2. Indications
The individual patient
Age (all pediatrics)
Cognitive ability
Mental/emotional state
Preference

10. Objective 3
Identify anesthesia equipment.

11. Objective 3. Equipment Anesthesia machine
Manual and automatic ventilation systems
Oxygen and nitrous oxide (N2O) central pipeline hoses and back up tanks

12. Objective 3. Equipment Vaporizers Flowmeters Breathing circuits
For volatile gases
Flowmeters
Breathing circuits
Gas scavenging systems

13. Objective 4
Explain the basic components of a general anesthetic.

14. Objective 4. Basic components
Patient is:
Unconscious
Pain-free
No memory of the event
Immobile
Maintains normal cardiovascular function

15. Objective 4. Basic components
Explain each:
Unconscious
Unaware, does not respond to stimuli
Pain-free (analgesia)
Does not experience pain

16. Objective 4. Basic components
Explain:
Retains no memory of the event (amnesia)
No explicit recall
No awareness under anesthesia

17. Objective 4. Basic components
Immobile
Muscles relaxed
Old term: “paralyzed”
Cardiovascular function
Goal: stable throughout

18. Objective 5
List methods of inducing general anesthesia.

19. Objective 5. Methods of general
Most common are:
Intravenous (IV)
Inhalation
Balanced
Combination of inhalation and intravenous

20. Objective 5. Methods of general
Rare, but possible:
Regional block used as an adjunct to a light general
High-risk patients

21. Objective 6
Define the phases of general anesthesia.

22. Objective 6. Phases Pre-induction Induction Maintenance Emergence
Recovery

23. Objective 6. Define phases
Pre-induction
Preoperative area
Assessment
Patient preparation
Up to admit to OR

24. Objective 6. Define phases
Induction
Preoxygenation
Administration of agents
Through airway management

25. INDUCTION ALERT!
Patients are highly reactive to noise during this phase. Pay attention to this when setting up your instruments.

26. Objective 6. Define phases
Maintenance
Starts when airway is secured/stable
Continues until end of procedure
Agents given PRN

27. Objective 6. Define phases
Emergence
Begins at end of procedure
Agents discontinued or allowed to wear off
Patient begins to awaken
Airway removed (PRN)

28. EMERGENCE ALERT!
Patients are highly reactive to noise in this phase. Be quiet and attentive to the patient when cleaning up.

29. Objective 6. Define phases
Recovery
Leave OR – go to PACU
Patient fully awakens
Vital signs must be stable before discharge

30. Objective 7
Discuss options for airway management.

31. Objective 7. Airway options
Mask
Placed over patient’s nose and mouth
Oxygen and inhalation agents given
Very short procedures
e.g., Myringotomy and tubes

32. Objective 7. Airway options
LMA
Laryngeal masked airway

33. Objective 7. Airway options
LMA
Sits on top of larynx
Administer oxygen and inhalation agents
Contraindications
Oral procedures, obesity, hiatal hernia, GERD, and low pulmonary compliance

34. Objective 7. Airway options
Endotracheal (ET) tube

35. Objective 7. Airway options
Endotracheal (ET) tube
Maximum airway control
Administer gases and inhalation agents
Longer procedures

36. Objective 7. Airway options
Endotracheal (ET) tube
When deep muscle relaxation is needed
Prone or lateral position

37. Objective 7. Airway options
Endotracheal (ET) tube
Variations:
RSI (rapid sequence)
Nasal
Patient awake

38. Objective 8
Describe the process of endotracheal intubation.

39. Objective 8. Intubation Patient’s muscles relaxed
Laryngoscope inserted
View vocal cords

40. Objective 8. Intubation Intubate (insert ET tube)
Inflate cuff PRN
Ventilate (O2 & agents)

41. Objective 9
Discuss the concept of awareness under anesthesia.

42. Objective 9. Awareness Rare Idiosyncratic 0.1-0.2% of all patients
Unpredictable
Unknown cause

43. Objective 9. Awareness
Some patients do NOT demonstrate characteristic physiologic responses to pain and/or inadequate depth of consciousness during surgery.

44. Objective 9. Awareness
Result: the patient may have direct recall of events during surgery.
Also called explicit memory
See Insight 15-4 in book

45. Objective 9. Awareness
Risk is  when it is necessary to use the lowest possible dose of anesthesia medications to avoid undesirable side effects.

46. Objective 9. Awareness Risk is  for: Trauma patients Cardiac patients
Obstetric patients

47. Objective 9. Awareness Highly variable, but
About 1/2 report auditory recall
About 1/2 report sensation of being unable to breathe
About 1/3 recall pain

48. Objective 9. Awareness How does this affect the surgical technologist?
We can no longer assume that the patient is unaware and unaffected by our conversations and comments during surgery.

49. Objective 9. Awareness How does this affect the surgical technologist?
Set a good example
Be an agent for positive change

50. Objective 10
List agents used to accomplish general anesthesia.

51. Objective 10. Agents by category
Sedatives/hypnotic agents
Analgesics
Inhalation agents
Neuromuscular blockers
Reversal agents

52. Objective 10. Agents by category

53. Objective 10. Agents Sedatives: Hypnotics: Benzodiazepines
Valium, Versed, Ativan
Hypnotics:
Barbiturates
Pentothal, Brevital

54. Objective 10. Agents
Other hypnotics
Ketamine
Etomidate
Propofol

55. Objective 10. Agents Analgesics Natural opioid: Synthetic opioids:
Morphine
Synthetic opioids:
Fentanyl
Alfentanil
Sufentanil
Remifentanil

56. Objective 10. Agents Inhalation agents Nitrous oxide
Isoflurane (Forane)
Desflurane (Suprane)
Sevoflurane (Ultane)

57. Objective 10. Agents Neuromuscular blockers Depolarizing
Succinylcholine
Non-depolarizing
Tracrium, Mivacron, Pavulon, Zemuron, Curare, Norcuron

58. Objective 10. Agents Reversal agents For opioids For benzodiazepines
Naloxone (Narcan)
Nalmefene (Revex)
Naltrexone (ReVia, Trexan)
For benzodiazepines
Flumazenil (Mazicon)

59. Objective 10. Agents Reversal agents
For non-depolarizing muscle relaxants:
Neostigmine (Prostigmine)
Edrophonium (Tensilon)

60. Objective 10. Agents

61. Objective 11
Identify the purposes and categories of agents used in general anesthesia.

62. Objective 11. Category/purpose
Sedatives/hypnotic agents
Produce unconsciousness
Analgesics
Prevent perception of pain
Inhalation agents
Prevent motor response to painful stimuli

63. Objective 11. Category/purpose
Neuromuscular blockers
Relax muscles for intubation and surgical procedure
Reversal agents
Counteract the action of various agents

64. Objective 12
Identify generic and trade names of common agents used in anesthesia.
Make drug cards
Generic name on one side
Trade name on other side

65. Objective 13
State the phase of anesthesia in which various agents are administered.
Make drug cards
Agent on one side
Phase on other side

66. Objective 13. Phase/agents
Induction
Benzodiazepines
Versed, Valium, Ativan
Barbiturates
Thiopental, methohexital
Ketamine
Etomidate
Propofol

67. Objective 13. Phase/agents
Induction and maintenance
Analgesics (PRN only)
Morphine
Sublimaze
Alfenta
Sufenta
Ultiva

68. Objective 13. Phase/agents
Induction and maintenance
Inhalation agents
Nitrous oxide
Forane
Suprane
Ultane

69. Objective 13. Phase/agents
Induction and maintenance
Inhalation agents

70. Objective 13. Phase/agents
Induction and maintenance
Depolarizing muscle relaxant
Succinylcholine
Non-depolarizers
Tracrium, Mivacron
Pavulon, Zemuron
Curare, Norcuron

71. Objective 13. Phase/agents
Emergence
Reversal agents:
Narcan, Revex, ReVia, Trexan
Mazicon
Prostigmine, Tensilon

72. Objective 14
Compare and contrast depolarizing and non-depolarizing muscle relaxants.
How are they alike?
How are they different?

73. Objective 14. C/C muscle relaxants
Basics – review physiology of muscle contraction - anatomy
Brain to motor nerve
Neuromuscular junction
Muscle fiber

74. Objective 14. C/C muscle relaxants
Basics – review physiology of muscle contraction – chemical level
Neurotransmitter
Acetylcholine (ACh)
Binds to receptor
Release Ca+

75. Objective 14. C/C muscle relaxants
Basics – review physiology of muscle contraction – chemical level
Depolarize (contract)
Acetylcholine (ACh) unhooks
Acetylcholinesterase removes ACh
Repolarize (resting)

76. Objective 14. C/C muscle relaxants
Depolarizers
Cause contractions (sustained)
Non-depolarizers
Prevent contractions

77. Objective 14. C/C muscle relaxants

79. Objective 14. C/C muscle relaxants
Similarities between depolarizing and non-depolarizing muscle relaxants
Both types paralyze muscles to allow intubation and surgical exposure
Both types are given IV

80. Objective 14. C/C muscle relaxants
How are they different?
Only 1 depolarizer
Many non-depolarizers
Depolarizer causes sustained contraction
Non-depolarizer prevents contraction

81. Objective 14. C/C muscle relaxants
How are they different?
Depolarizer
Rapid onset
Short duration
Not reversible

82. Objective 14. C/C muscle relaxants
How are they different?
Non-depolarizers
Vary in onset and duration
Reversible

83. Objective 14. C/C muscle relaxants
How are they different?
Depolarizer
Trigger for Malignant Hyperthermia (see Chapter 16)
Non-depolarizers
Not implicated in MH