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1

Important to give to pregnant mom before epidural is placed?

Antacid (reduce risk of aspiration pneumonitis)

During pregnancy, there is decreased gastric emptying (increased progesterone) and displacement of the pylorus from the distended uterus

A risk of epidural is total spinal anesthesia --> may need to be intubated and always a risk of aspiration pneumonitis w/ intubation.

2

Inhaled halogenated gas effect on uterus?

Relaxes uterus

3

During carotid endarterectomy, dissection of the carotid body results in stimulation of carotid body and reflex bradycardia. What 2 options can help treat this reflex?

Injecting 1% Lidocaine into carotid body
OR
IV Atropine (reverse the bradycardia)

4

What is malignant hyperthermia?

How long until it presents?

What is treatment?

Hyper metabolic response to inhaled halogenated anesthetics (e.g halothane) or depolarizing agents (succinylcholine) --> massive uncontrolled intracellular Ca release from sarcoplasmic reticulum

Presents w/in 30 minutes of starting anesthesia

Tx:
1) D/C offending agent
2) DANTROLENE

5

What gene is red flag for possible malignant hyperthermia?

RVR1 gene (ryanodine receptor gene)

6

Signs of malignant hyperthermia?

1) Hyperthermia (climbs 1-2 degrees every 5 minutes)
2) Muscle Rigidity (sustained muscle contractions, especially masseter)
3) Tachycardia
4) Cyanosis & skin mottling

Presents w/in 30 minutes of starting anesthesia

7

Why are crystalloids NOT an adequate source to improve BP over long term?

Only 1/3 of volume infused remains in intravascular space --> if you need to raise BP after persistent hypotension (shock), then use PRBC

8

During operation, a man's HR is 145 while his pressure and urine output are stable. Post-op, he is profoundly hypotensive (

Likely cardiac event (intra-op) causing increased myocardial demand but low cardiac output = ischemic event --> now has cardiogenic shock (low cardiac output & vasoconstriction from increased peripheral resistance)

Mgmt: inotropic agent (dobutamine)

9

Maximum dose of lidocaine for numbing agent?

300mg ; 500mg if used w/ epinephrine

For 1% solution --> 1g/100mL (10mg/mL)
300mg/(10mg/mL) = **30mL max**

For 2% solution --> 2g/100mL (20mg/mL)
300mg/(20mg/mL) = **15mL max**

10

What 2 drugs are in Vicodin? What are their concentrations and dosages?

hydrocodone & acetaminophen --> 5mg/300-325mg
1-2 tab PO q 4-6 hrs PRN

11

Patient has jugular distention w/ B/L rales over both lung bases. What should most likely be done prior to elective surgery?

Treat patient for CHF (ACEi, B-blocker, diuretics, dig)

CHF (JVD, rales B/L @ bases) very risky for elective surgery

12

What local anesthetic, if it gains systemic access, can cause cardiac arrest? What is antidote?

Liposomal bupivicaine

Tx: Intra-lipid rescue

13

Shortly after spinal anesthesia is placed, patient's blood pressure drops to 75/20. He looks warm and flushed but central venous pressure is near 0. What are you thinking? What should be included in his therapy?

Neurogenic shock --> high spinal anesthetic can produce vasomotor shock by inducing widespread vasodilation caused by sympathetic blockage

Tx: a-adrenergic peripheral vasoconstrictor

14

Why are hypotonic solutions not often administered?

Cause cellular swelling

15

Why can't LR be given with PRBC's?

Potential for initiating clotting cascade due to presence of Ca in LR

16

What are the 4 components for fluid requirements?

1) Maintenance (4-2-1 or wt + 40) for hourly isotonic fluids
2) Insensible losses: sweat, airway, etc
3) Urine output, NG tube
4) "3rd space" losses: due to surgical trauma - replaced w/ b/w 4-10mL/kg/hr

17

Of the new fluid replacement strategy, what are 2 changes to the protocol?

1) Ignore pre-op NPO deficits when calculating replacement

2) fluid admin begins w/ colloid (6% Hespan) to replace blood loss at 1:1 ratio. If blood loss exceeds 1.5L, then crystalloid is added

18

How much volume of water comprises 1 kg of body weight?

1 liter water in 1 kg body wt

19

Muscle relaxant w/ increased risk/incidence of pulmonary complications?

Pancuronium (long half-life & risk of residual muscle weakness including diaphragm)

20

Most important predictor for risk of pulmonary complications during surgery?

Location of surgical excision to diaphragm (thoracic & upper abdominal have highest risk)

21

In a patient w/ chronic kidney failure, what opioid must NOT be used?

Meperidine (renal clearance)

22

Important drugs for consideration before surgery?

1) B-blockers (decrease peri-op morbidity) --> use this to get HR 70 & Systemic BP 110
2) Anti-HTN's: D/C ACEi/ARBS!! but continue other anti-HTN meds
3) D/C MAOIs
4) D/C herbals

23

What anti-HTN must be continued during surgery or risk refractory HTN crisis during operation?

Clonidine & B-blockers --> their receptors are unregulated and d/c-ing them results in hypersensitivity of the receptors

24

Most common drugs used during anesthesia to cause anaphylaxis?

Paralytic muscle relaxants, NOT Abx

25

What 2 conditions cause laxity in transverse ligament that secures the dens of C2 and are contraindications for direct laryngoscopy?

Rheumatoid arthritis
Down syndrome

26

In emergency situations, what blood type is generally used, except in childbearing-age women and why?

O+ most commonly given

NOT given in childbearing-age women b/c the (+) Rhesus factor can cause Ab formation in mom and cause future erythroblastosis fetalis in subsequent pregnancies!!

27

What is "Type and Screen" mean?

Type: the ABO and Rhesus factors are identified in patient's blood

Screen: patient's blood screened for presence of various Ab's via indirect Coombs test

This take only minutes

28

What is "Type and Crossmatch"?

Type: patient's blood tested for ABOU & Rhesus factor identification

Crossmatch: donor's RBCs exposed to patient's serum - looking for any reactions

More time consuming and expensive

29

What physical sign can tell you if a person is in Stage 2 of anesthesia (moderate sedation)?

What common mistake is made during this stage?

Divergent eye gaze: not looking at me when I open their eyelids

Patient starts to cough and gag against ET tube, especially if they are a smoker. Tendency is to want to pull out the ET tube --> DO NOT PULL IT OUT! They could laryngospams and lose the airway!

30

Where is the epidural space located?

It's a potential space located b/w the ligamentum flavum and dura

31

Where is the intrathecal/subarachnoid space located?

Beneath the arachnoid mater

32

Layers of the back?

Skin, sub-Q, muscle, supraspinous ligament, interspinous ligament, ligamentum flavum, dura/arachnoid mater

33

What neural structures does an epidural act on? Intrathecal?

Epidural --> BOTH spinal cord & spinal roots

Intrathecal --> ONLY spinal cord

34

What drug tends to inhibit sensory neurons before motor neurons?

Bupivicaine (& derivatives)

35

DOC for labor anesthesia? Why?

Bupivicaine --> only eliminates sensory perception but still allows mom to have motor control (pushing the baby out!)

36

What is "baricity?"

Density of drug relative to CSF

Hyperbaric = "sinks" once administered into CSF
Hypobaric = "floats" once administered into CSF

*Patient positioning very important for drug distribution

37

During regional anesthesia, what nerves are easiest to inhibit first? What effect does this have?

Sympathetic nerves!

Basal sympathetic tone = vasoconstriction
*If sympathetic tone (-) by regional block --> you often get vasodilation --> hypotension from decreased preload --> proportionate to spinal level of injection (higher in spine = more vascular affected)

38

Feared complication of neuraxial blockade?

Epidural hematoma

39

Why are finger/toe blocks done W/O epinephrine?

Vasoconstriction from Epinephrine causes distal necrosis of digits

40

In small children, when peripheral access is not accessible via IV, what is the preferred route of access?

Intraosseous (IO) cannulation

41

3 important potential side effects of Protamine Sulfate infusion during surgery?

1) Induce histamine release causing vasodilation --> hypotension

2) Anaphylactoid-like reaction (hypotension, bronchospasm, urticaria) --> tx w/ epinephrine + fluids

3) Increases pulmonary artery pressures

42

What is correlation b/w vasectomies & protamine sulfate?

Increased chance of allergic-like reaction to protamine

43

What can be given before propofol infusion to reduce burning sensation?

Lidocaine

44

Name 2 important effects of lidocaine prior to induction?

1) Mild sedating effect
2) Blunts response from stimulation of laryngoscopy

45

If child becomes bradycardic during laryngospasm, what is drug to use?

Succinylcholine --> give you several minutes to secure airway b/w laryngospasms

Initially during laryngospasm, the child will be tachycardic --> over time, if the laryngospasm doesn't break, they will become bradycardic

46

What is another option to try prior to succ that breaks laryngospasm 50% of the time?

PPV

47

What is important to do prior to extubation to help prevent laryngospasm?

Suction secretions from throat/oropharynx

Stay midline, especially w/ throat surgery, to prevent bleeding

48

For acute pain control, how long until IV opioids take effect?

Less than 8 minutes --> if no response, increase dose by 50% (for morphine)

49

Which opioid has the highest amount of histamine release?

Morphine

50

Very short acting opioid w/ NO histamine release?

Fentanyl (vs. morphine w/ high histamine release)

51

What is treatment for N/V secondary to opioids?

Anti-cholinergics --> they block muscarinic receptors & inhibit cholinergic transmission from vestibular nuclei to vomiting center

52

If 1 dose of Zofran doesn't work for nausea?

MOVE ON to another drug --> no effect on nausea; only vomiting!

53

Anti-dopaminergic antiemetics?

Phenergan & compazine

54

Pro-kinetic agent used for reducing N/V?

Used a lot in what anesthetic situation?

Metoclopramide

OBGYN (deliveries)

55

Situations to NOT give succinylcholine?

Burns, muscular dystrophies, children under certain ages (undiagnosed muscular dystrophies), hyperkalemia

56

If you give succinylcholine and person suddenly becomes asystolic/dysrrhythmia , what is going on?

Hyperkalmia

57

If person is acidotic or alkalotic (etCO2), what are 2 ways you can handle this problem?

Change:
1) RATE of ventilations
2) VOLUME of ventilations

58

Which drug used for reflux disease can inhibit volatile anesthetic metabolism, leading to high drug concentrations?

Cimetidine

59

Which drug used for reflux disease can inhibit volatile anesthetic metabolism, leading to high drug concentrations?

Cimetidine (H2 blocker)

60

What duration and dosage of steroids must you consider giving a higher stress dose of short-acting glucocorticoids prior to surgery?

Higher stress dose w/ >3wk duration of >20mg

Pt's on

61

What IV anesthetic INHIBITS steroid synthesis & can cause acute adrenal crisis?

Etomidate

Avoid during surgery in patients w/ suspected HPA suppression

62

What is most potent regulator of cerebral blood flow (CBF)?

How does this work?

PaCO2

As cerebral PaCO2 levels rise = blood flow rises (vasodilation)
*Hypoventilation

As cerebral PaCO2 decreases = blood flow decreases (vasoconstriction)
*Hyperventilation

63

What is it bad for person to bite down on ET tube and take big inhalation breath?

What other condition can this occur?

Negative pressure pulmonary edema --> closed upper airway results in very large negative intrathoracic pressure (near -100 cmH2O) generated by patient's increased effort to breath. This causes increase in LV preload & afterload. It also causes a decrease in extramural hydrostatic pressure. The hypoxia changes pulmonary vascular resistance (vasoconstriction) --> RV dilation, intraventricular septum deviates to L & LV diastolic dysfunction occurs. This causes flash pulmonary edema

Laryngospasm another cause!

64

What is a cause for the SpO2 to suddenly drop while HR, BP, etCO2 are all normal?

Inflated BP cuff on same arm as pulse ox monitor

65

First step in person with post-op disorientation? Why?

Start supplemental O2 --> most lethal cause of post-op disorientation is hypoxia

**Transient hypoxia is not uncommon after surgery --> often breathe shallowly due to incisional pain and narcotic use

66

What are parameters for extubation?

Rapid shallow breathing index --> ratio of resp rate to tidal volume
*Lower the # the better --> low resp rate w/ high tidal volume
*Cutoff is

67

Ventilator tidal lung volumes used during intubation:
Asthma?
COPD?
ARDS?

Asthma =

68

Preferred method to establish an airway in person with cervical spine injury and apneic?

Orotracheal intubation with rapid-sequence intubation

69

Man had a MVA and is severely hypotensive. He requires several units of PRBC for transfusion. Once he is stabilized, he complains of paresthesias in his fingers and toes. His blood Ca2+ is low. Why?

Citrate is stored with packed/whole RBC to prevent anticoagulation.

The citrate will chelate serum Ca2+ = hypocalcemia

70

What are contraindications for succinylcholine use?

Hyperkalemia
- Depolarizing agent causing massive K release from cells

*Crush/burn injuries >8hrs old
*Demyelinating syndromes (Guillan-Barre)
*Tumor lysis syndrome

71

What is MOA of non-de polarizing NM agents?

How to reverse their effects?

Competitive blockers of ACh at 1 of 2 alpha subunits on ACh receptor on motor end plate

ACh-esterase blocker --> neostigmine, pyridostigmine, physostigmine, edriphonium

72

What Hb levels should you give PRBCs?

Stable patients --> if Hb if Hb

73

What should always be done to confirm placement of CV catheter?

CXR --> proximal to cardiac silhouette or angle b/w trachea and R mainstem bronchus

74

What induction agent will people maintain their respiratory drive and not become apneic?

Etomidate

75

What effect does methylene blue have with MAOIs?

Can cause serotonin syndrome --> inhibits MAOI action

76

What is the Curarie Cleft?

On etCO2 waveform, if the patient is trying to initiate spontaneous breaths while the ventilator is rest, there will be a downward deflection of the waveform (slight inspiration effort) during mid-exhalation on the vent

Indicates patient is coming out of anesthesia

77

Common side effect of Zofran?

Headache