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Flashcards in Chapter 8: Anesthesia Deck (78):
1

- Blunt hypoxic drive
- Caused unconsciousness, amnesia, some analgesia
- Most have myocardial depression, increase CBF, decrease RBF

Inhalational agent

2

Smallest concentration of inhalation agent at which 50% of patients will not move with incision

MAC (minimum alveolar concentration)

3

Fast, minimal myocardial depression; tremors at induction

Nitrous oxide (NO2)

4

- Slow onset / offset, highest degree of cardiac depression and arrhythmias
- Least pungent, which is good for children

Halothane

5

Manifestations of halothane hepatitis

Fever, eosinophilia, jaundice, increased LFTs

6

Fast, less laryngospasm and less pungent; good for mask induction

Sevoflurane

7

Good for neurosurgery (lowers brain oxygen consumption; no increase in ICP)

Isoflurane

8

Can cause seizures

Enflurane

9

- (Barbiturate) fast acting
- Side effects: decrease CBF and metabolic rate, decrease blood pressure

Sodium thiopental

10

- Very rapid distribution and on/off; amnesia; sedative
- Not an analgesic
- Metabolized in liver and by plasma cholinesterase's
- Side effects: hypotension, respiratory depression

Propofol

11

Dissociation of thalamic / limbic systems; places patient in a cataleptic state (amnesia, analgesia).
- No respiratory depression
- Contraindicated in patients with head injury
- Good for children

Ketamine

12

Side effects: hallucinations, cathetcholamine release (increase CO2, tachycardia), increased airway secretions and increased cerebral blood flow

Ketamine

13

- Fewer hemodynamic changes; fast acting
- Continuous infusions can lead to adrenocortical suppression

Etomidate

14

When is RSI indicated?

- Recent oral intake
- GERD
- Delayed gastric emptying
- Pregnancy
- Bowel obstruction

15

Last muscle to go down and first muscle to recover from paralytics

Diaphragm

16

First to go down and last to recover from paralytics

Neck muscles and face

17

Only one is succinylcholine; depolarizes neuromuscular junction

Depolarizing agents

18

- Caused by a defect in calcium metabolism
- Calcium released from sarcoplasmic reticulum causes muscle excitation: contraction syndrome

Malignant hyperthermia

19

First sign of malignant hyperthermia

Increased end-tidal CO2

20

Side effects: first sign is increased end-tidal CO2, then fever, tachycardia, rigidity, acidosis, hyperkalemia

Malignant hyperthermia

21

Tx: dantrolene (10mg/kg) inhibits calcium release and decouples excitation; cooling blankets, HCO3, glucose, supportive care

Malignant hyperthermia

22

When do you NOT use succinylcholine?

Severe burns.
Neurologic injury.
Neuromuscular disorders.
Spinal cord injury.
Massive trauma.
Acute renal failure.

23

Complications of succinylcholine

- Malignant hyperthermia
- Hyperkalemia
- Open-angle glaucoma
- Atypical pseudocholinesterases

24

- Inhibits neuromuscular junction by competing with acetylcholine
- Can get prolongation of these agents with myasthenia gravis

Nondepolarizing agents

25

Non-depolarizer
- Undergoes Hoffman degradation
- Can be used in liver and renal failure
- Histamine release

Cis-atracurium

26

Non-depolarizer: Fast, intermediate duration; hepatic metabolism

Rocuronium

27

Non-depolarizer:
- Slow acting, long-lasting; renal metabolism
- Most common side effect: tachycardia

Pancuronium

28

Blocks acetylcholinesterase, increasing acetylcholine

Neostigmine
Edrophonium

29

Should be with neostigmine or edrophonium to counteract effects of generalized acetylcholine overdose

Atropine or glycopyrrolate

30

Work by increasing action potential threshold, preventing Na influx.
- Can use 0.5 cc/kg of 1% lidocaine.

Local anesthestics

31

Why are infected tissues difficult to anesthetize with local anesthetics?

Secondary to acidosis.

32

Length of action of local anesthetics: greatest to least

Bupivacaine > lidocaine > procaine

33

Side effects of local anesthetics

Tremors
Seizures
Tinnitus
Arrhythmias (CNS symptoms occur before cardiac)

34

What does addition of epinephrine to local anesthetics allow?

Allows higher doses to be used, stays locally

35

When do you not use epinephrine with local anesthetics?

No epi with:
Arrhythmias, unstable angina, uncontrolled hypertension, poor collaterals (penis and ear), uteroplacental insufficiency

36

Two different genres of local anesthetics

Amides (all have "i" in first part of their name)
Esters

37

Allergic reactions: amides vs esters

Esters: increased allergic reactions due to PABA analogue

38

Metabolism: opioids

Metabolized by the liver and excreted via kidney

39

What can narcotics cause precipitate in patients on MAOIS?

Hyperpyrexic coma

40

Analgesia, euphoria, respiratory depression, miosis, constipation, histamine release (causes hypotension), decreased cough

Morphine

41

Analgesia, euphoria, respiratory depression, miosis, tremors, fasciculations, convulsions

Demerol

42

Does demerol cause histamine release?

NO.

43

Why avoid demerol in patients with renal failure?

Can cause seizures (buildup of normeperidine analogues)

44

simulates morphine, less euphoria

Methadone

45

Fast acting; 80x strength of morphine (does not cross-react in patients with morphine allergy); no histamine release

Fentanyl

46

Very fast acting narcotics with short half lives

Sufentanil and remifentanil

47

Most potent narcotic

Sufentanil

48

Anticonvulsant.
Amnesic.
Anxiolytic.
Respiratory depression.

Benzodiazepines

49

Do benzodiazepines have pain relief?

No.

50

Metabolism: benzos

Liver

51

Benzo:
- Short acting
- Contraindicated in pregnancy
- Crosses placenta

Versed (midazolam)

52

Benzo:
- Intermediate acting

Valium (Diazepam)

53

Benzo:
- Long acting

Ativan (lorazepam)

54

- Benzo OD
- Competitive inhibitor
- May cause seizures and arrhythmias
- Contraindicated in patients with elevated ICP or status epilepticus

Flumazenil

55

MC side effect flumazenil

Nausea

56

Allows analgesia by sympathetic denervation.
Vasodilation.

Epidural anesthesia

57

Epidural with morphine

Can cause respiratory depression

58

Lidocaine in epidural

Decreased heart rate and blood pressure

59

How can motor function be spared with epidural?

Dilute concentrations

60

Tx: acute hypotension / bradycardia with epidural

Turn epidural flows down.
Fluids.
Phenylephrine.
Atropine

61

Epidural level: affect cardiac accelerator nerves

T1-5

62

Contraindications: epidural

Hypertrophic cardiomyopathy.
Cyanotic heart disease.

63

Why h-cmp and cyanotic heart disease contraindications to epidural anesthesia?

Sympathetic denervation causes decreased after load, which worsens these conditions

64

Injection into subarachnoid space, spread determined by baricity and patient position

Spinal anesthesia

65

Contraindications: spinal

Hypertrophic cardiomyopathy.
Cyanotic heart disease.

66

Caused by CSF leak after spinal / epidural.
Headache gets worse sitting up.

Spinal headache

67

Tx: Spinal headache

Rest. Fluids. Caffeine. Analgesics. Blood patch to site if it persists > 24 hours.

68

Associated with most postop hospital mortality

1. Pre-op renal failure
2. CHF

69

May have no pain or EKG changes. Can have hypotension, arrhythmias, increased filling pressures, oliguria, bradycardia.

Postop MI

70

Patients who need cardiology workup pre-op (x13)

Angina. Previous MI. SOB. CHF. METs 5min. High grade heart block. Age >70. DM. Renal insufficiency. Patients undergoing major vascular surgery.

71

Considered high risk surgery

Most aortic, major vascular, peripheral vascular surgery

72

Risk: carotid endarterectomy (CEA)

Considered moderate risk surgery

73

Biggest risk factors for post MI

Age > 70.
DM.
Previous MI.
CHF.
Unstable angina.

74

Best determinate of esophageal vs tracheal intubation

End-tidal CO2

75

Intubated patient undergoing surgery with sudden transient rise in ETCO2
Dx? Tx?

Dx: most likely hypoventilation.
Tx: increased tidal volume or increased respiratory rate.

76

Goal endotracheal tube placement

2cm above the carina

77

Associated with lower mortality for abdominal aortic aneurysm repair and for pancreatic resection

Higher volume hospitals

78

MC PACU complication

nausea and vomiting.