Lecture 4 (Part 2)-Pediatric Pharmacology

Question 1

Premature infant = an infant that was born at < ___ weeks post conception (gestational age)

Answer 1

< 37 weeks

Question 2

Neonate/newborn = ___-___ weeks of age

Answer 2

0-4 weeks of age

Question 3

Infant = ___ weeks to ___ months of age

Answer 3

4 weeks to 12 months of age

Question 4

Pharmacological maturation occurs between ___-___ months of age

Answer 4

3-6 months of age

Question 5

Drug absorption—there is no structural difference between infants, children, and adults that affect ___ absorption of drugs

Answer 5

GI

Question 6

Drug absorption—there are differences in the neonate related to pH—___ (more/less) acidic; gastric ___; and gastric ___ time—markedly ___ (slower/faster)

Answer 6

pH—less acidic; gastric emptying; and gastric transit time—markedly slower

Question 7

The amount of drug that reaches specific body compartments or tissues (the concentration of drug at the receptor site) is regulated by the ___ process

Answer 7

Distribution

Question 8

Drug distribution—IV drugs are influenced by ___ binding, ___ binding, tissue ___, tissue ___ coefficients, tissue ___ flow

Answer 8

Protein binding, RBC binding, tissue volumes, tissue solubility coefficients, tissue blood flow

Question 9

The neonate has a qualitative and quantitative ___ (increase/decrease) in protein binding

Answer 9

Decrease

Question 10

There is a ___ (increase/decrease) in the number of plasma proteins, and a ___ (increase/decrease) in the affinity of proteins for drugs in the neonate

Answer 10

Decrease in the number of plasma proteins, and a decrease in the affinity of proteins for drugs in the neonate

Question 11

The reduction in protein binding in neonates contributes to the apparent ___ (smaller/larger) volume of distribution in comparison to adult proportions

Answer 11

Larger volume of distribution

Question 12

Neonates/infants have ___ (increased/decreased) total body water and extracellular fluid compared to adults

Answer 12

Increased

Question 13

Neonates/infants have ___ (increased/decreased) blood volume, intracellular water, muscle mass, and fat compared to adults

Answer 13

Decreased

Question 14

Full-term infants have greater ___ compared to adults

Answer 14

Blood volume

Question 15

Infants go through a period of ___ following birth (3-6 months) with the destruction of fetal ___ and the concurrent but slow production of ___—this is referred to as the physiologic ___ of hemoglobin

Answer 15

A period of anemia following birth (3-6 months) with the destruction of fetal hemoglobin and the concurrent but slow production of RBCs—this is referred to as the physiologic nadir of hemoglobin

Question 16

Total body ___, ___cellular fluid, and ___ volume are relatively larger when comparing the neonate with the child or adult on a per kg scale; this initial larger volume of distribution may explain why the neonate requires ___ (lower/higher) per kg doses of drugs to reach the desired effect

Answer 16

Total body water, extracellular fluid, and blood volume are relatively larger when comparing the neonate with the child or adult on a per kg scale; this initial larger volume of distribution may explain why the neonate requires higher per kg doses of drugs to reach the desired effect

Question 17

The blood brain barrier is ___ (mature/immature)

Answer 17

Immature

Question 18

Lipid soluble drugs diffuse ___

Answer 18

Easily

Question 19

Rate of entry of drugs is based on blood ___

Answer 19

Flow

Question 20

The infant’s brain receives a ___ (small/large) proportion of cardiac output in comparison to the adult, and the resultant brain concentration of many drugs is ___ (higher/lower) in the infant than in the adult

Answer 20

Large proportion of cardiac output, resultant brain concentration of many drugs is higher in the infant than in the adult

Question 21

A high proportion of cardiac output is distributed to the vessel ___ (poor/rich) group, particularly the ___

Answer 21

Vessel rich group, particularly the brain

Question 22

Smaller ___ mass and ___ stores (in relation to adults on a per kg basis) provide ___ (more/less) uptake to inactive sites and tend to keep plasma volumes ___ (lower/higher)

Answer 22

Smaller muscle mass and fat stores provide less uptake to inactive sites and tend to keep plasma volumes higher

Question 23

The ability to metabolize drugs develops to the same degree in the same time period after birth in the premature infant and the full term infant—T/F?

Answer 23

True

Question 24

___ age, not gestational age, is more important in determining the maturity of drug metabolism

Answer 24

Postnatal age

Question 25

Hepatic enzyme systems are ___ developed or ___ at birth

Answer 25

Incompletely developed or absent at birth

Question 26

Phase I and II processes are limited but develop within ___ after birth

Answer 26

Develop within a few days after birth

Question 27

Conjugation reactions are developed by ___ months

Answer 27

3

Question 28

The ultimate elimination of most drugs or their metabolites is by ___ excretion

Answer 28

Renal

Question 29

Drug clearance may be ___ (reduced/enhanced) in the neonate

Answer 29

Reduced

Question 30

Clearance of most drugs reaches adult values by ___ months of age

Answer 30

3 months of age

Question 31

The uptake of inhaled anesthetics is more ___ (slow/rapid) in infants and small children than in adults

Answer 31

Rapid

Question 32

Tidal volume is relatively constant throughout life—___ml/kg

Answer 32

7 ml/kg

Question 33

Infants have a ___ (lower/higher) alveolar ventilation in relation to FRC

Answer 33

Higher alveolar ventilation in relation to FRC

Question 34

Va/FRC = ___:___ in infants; ___:___:___ in adults

Answer 34

5: 1 in infants
1: 4:1 in adults

Question 35

Uptake and distribution—the infant has ___ (more/less) muscle mass on a per kg scale in relation to adults and a ___ (increase/decrease) in the proportion of cardiac output perfusing muscle in relation to adults

Answer 35

The infant has less muscle mass on a per kg scale in relation to adults and a decrease in the proportion of cardiac output perfusing muscle in relation to adults

Question 36

Uptake and distribution—distribution of cardiac output is higher to the vessel ___ group (the ___) vs. adults

Answer 36

Higher to the vessel rich group (the brain) vs. adults

Question 37

Shunting is more pronounced with insoluble agents such as ___ and ___

Answer 37

N2O and sevoflurane

Question 38

Effects of shunting—___ to ___ shunt (as seen in patients with tetralogy of fallot, transposition of the great arteries, tricuspid atresia, and total anamolous pulmonary venous return) ___ (slows/speeds) uptake of agent; partial pressure of agent increases more ___ly; over-pressuring can be dangerous; ___ on means ___ off

Answer 38

R to L shunt slows uptake of agent; partial pressure of agent increases more slowly; over-pressuring can be dangerous; slow on means slow off

R to L shunt—deoxygenated blood on the right side of the heart shunts to the left side of the heart; slows uptake of agent because the blood on the right side of the heart isn’t going to the lungs to pick up agent

Over-pressuring can be dangerous because it takes a long time for the agent to come off, so the myocardial depressant effects will be long lasting

Question 39

Effects of shunting—___ to ___ shunt (as seen in patients with ASD, VSD, PDA, BT shunt) uptake of agent is ___ (slower/faster); increase in uptake depends on ___ of shunt; large shunt (>80%) results in a ___ increase in agent partial pressure; small shunt (<50%) the change is ___

Answer 39

L to R shunt uptake of agent is faster; increase in uptake depends on size of shunt; large shunt results in a rapid increase in agent partial pressure; small shunt the change is negligible

L to R shunt—oxygenated blood from the left side of the heart is going to the right side of the heart (so body is not receiving the oxygen that it needs)

Question 40

MAC—there is an ___ (direct/indirect) relationship between MAC of inhalation agents and age

Answer 40

Indirect relationship—the younger the child, the more agent needed (and vice versa)

Question 41

Studies show that MAC of fetal lamb is ___ (lower/higher) than that of newborn lamb

Answer 41

Lower

Question 42

MAC ___ (increases/decreases) during the first month of life

Answer 42

Increases

Question 43

MAC starts to ___ (increase/decrease) after 6 months of life

Answer 43

Decrease

Question 44

In the first week of life, the neonate’s response to pain is ___; the sensitivity and response to pain mature rapidly in the first few months of life

Answer 44

Diminished

Question 45

Age-dependent differences in inhaled anesthetic requirements may be attributed to changes in ___ solubility, as well as the high ___ content of the neonatal brain

Answer 45

Changes in blood-gas solubility, as well as the high water content of the neonatal brain

Question 46

Incidence of bradycardia, hypotension, and cardiac arrest during induction is ___ (lower/higher) in infants than in adults; this is due to the ___ (increased/decreased) amount of agent administered and ___ (increased/decreased) sensitivity of the cardiovascular system

Answer 46

Higher; this is d/t the increased amount of agent administered and increased sensitivity of the cardiovascular system

Question 47

The baroreceptor reflexes of the neonate and premature infant are limited; anesthetic agents further blunt these reflexes and put the infant at a disadvantage during anesthesia with potent inhaled agents—T/F?

Answer 47

True

Question 48

Halothane ___ the myocardium in direct proportion to the depth of anesthesia

Answer 48

Depresses

Question 49

Halothane acts as a ___ blocker

Answer 49

Calcium channel blocker

Question 50

Halothane causes a decrease in ___, ___ vascular resistance, and cardiac ___

Answer 50

Decrease in contractility, pulmonary vascular resistance, and cardiac slowing

Question 51

___ heart tones, ___cardia, and ___tension are initial signs of halothane overdose

Answer 51

Muffled heart tones, bradycardia, and hypotension are initial signs of halothane overdose

Question 52

Isoflurane has a direct negative ___tropic effect; causes a marked decrease in ___; has less depressant and fewer cardiovascular effects than ___

Answer 52

Direct negative inotropic effect; causes a marked decrease in PVR; has less depressant and fewer cardiovascular effects than halothane

Question 53

Isoflurane is not used for inhalation induction d/t ___ smell and airway ___

Answer 53

Pungent smell and airway irritation

Question 54

Sevoflurane is ___ (less/more) soluble than halothane or isoflurane and has a more ___ wash in

Answer 54

Less soluble and has a more rapid wash in

Question 55

This agent maintains cardiovascular homeostasis and produces fewer dysrhythmias than halothane or isoflurane

Answer 55

Sevoflurane

Question 56

The addition of ___ decreases the MAC of sevoflurane proportionately in adults

Answer 56

N2O

Question 57

The addition of 60% N2O decreases the MAC of sevoflurane in children 1-3 years old by only ___%

Answer 57

25%

Question 58

This inhalation agent has a strong pungent smell and is irritating to the airways

Answer 58

Desflurane

Question 59

Desflurane is not used as an induction agent because of the high incidence of severe ___ in infants and children

Answer 59

Laryngospasm

Question 60

Cardiac stability is maintained with desflurane, but ___ is decreased

Answer 60

SVR

Question 61

Desflurane—high incidence of emergence ___ in pediatric population

Answer 61

Emergence delirium

Question 62

MAC values in the neonate vs. adult—halo ___

Answer 62

Neonate halo = 0.87%

Adult halo = 0.75%

Question 63

MAC values in the neonate vs. adult—iso ___

Answer 63

Neonate iso = 1.6%

Adult iso = 1.2%

Question 64

MAC values in the neonate vs. adult—sevo ___

Answer 64

Neonate sevo = 3.3%

Adult sevo = 2.05%

Question 65

MAC values in the neonate vs. adult—des ___

Answer 65

Neonate des = 9.2%

Adult des = 7%

Question 66

Inhalation induction is often done in infants and children because they are usually uncooperative with ___ starts

Answer 66

IV

Question 67

Inhalation induction—___ (increased/decreased) minute ventilation and ___ (small/large) body mass makes inhalation inductions safer and faster in children

Answer 67

Increased minute ventilation and small body mass

Question 68

Inhalation induction—stage ___ is limited, therefore decreasing the chances of ___ during induction

Answer 68

Stage II is limited, therefore decreasing the changes of laryngospasm during induction

Question 69

Inhalation induction—current method with sevoflurane—O2/N2O at ___L/___L; sevoflurane at ___% until patient is deep enough for IV start; this produces rapid stun effect for an anxious or uncooperative child but must be followed with continued administration of ___ agent or ___ anesthetic

Answer 69

O2/N2O at 2L/4L; sevoflurane at 8%; continued administration of IV agent or inhalation anesthetic

Question 70

Inhalation induction—old method with halothane—O2/N2O at ___L/___L; introduce halothane at ___% increments every 2-3 breaths until ___-___%; allow patient to deepen enough for IV to be started and decrease agent dose; decrease agent dose to prevent ___tension and ___cardia

Answer 70

O2/N2O at 2L/4L; introduce halothane at 0.5% increments every 2-3 breaths until 3-5%; allow patient to deepen enough for IV to be started and decrease agent dose; decrease agent dose to prevent hypotension and bradycardia

Question 71

Induction with sevo—decrease agent as soon as the maximal point in ___ is reached; come down to ___-___%

Answer 71

Decrease agent as soon as the maximal point in heart rate is reached; come down to 3-5%

Question 72

Midazolam—used as pre-operative ___lytic for kids ~___ months or older (when separation anxiety begins)

Answer 72

Pre-operative anxiolytic for kids ~9 months or older

Question 73

Midazolam oral dose ___-___ mg/kg, onset ___-___ minutes

Answer 73

0.5-1.0 mg/kg, onset 15-30 minutes

Question 74

Midazolam intranasal dose ___-___ mg/kg, onset ___ minute with peak in ___ minutes

Answer 74

0.2-0.3 mg/kg, onset 1 minute with peak in 10 minutes

Question 75

Midazolam IV dose ___-___ mg/kg

Answer 75

0.1 mg/kg

Question 76

Propofol—infants ___ mg/kg

Answer 76

3 mg/kg

Question 77

Propofol—older children ___ mg/kg

Answer 77

2.4 mg/kg

Question 78

Propofol induction dose is typically ___-___ mg/kg

Answer 78

2-5 mg/kg

Question 79

Propofol—rapid redistribution and metabolism result in a ___ (long/short) duration of action

Answer 79

Short

Question 80

Propofol can be used for ___ of general anesthesia and may be used as an ___ for maintenance of general anesthesia; propofol doses in pediatric patients are much ___ (lower/higher) than in adults

Answer 80

Can be used for induction of GA and may be used as an infusion for maintenance of GA; much higher

Question 81

Ketamine—IV ___ mg/kg

Answer 81

2 mg/kg

Question 82

Ketamine—IM ___ mg/kg

Answer 82

3-6 mg/kg

Question 83

Ketamine can be given in intermittent ___ for sedation, as an ___, or as an IM ___ for uncooperative patient (usually given this way for autistic patients)

Answer 83

Intermittent blouses for sedation, as an infusion, or as an IM dart for uncooperative patient

Question 84

Ketamine has potent analgesic properties for skin, muscle, and bone, but not for ___

Answer 84

Viscera

Question 85

Ketamine causes increased ___, so give with an anti___

Answer 85

Increased salivation, so give with an antisialogogue

Question 86

Ketamine causes ___ as well and should be co-administered with a ___

Answer 86

Hallucinations; administer with a benzo (i.e.: versed)

Question 87

Neonates have an increased sensitivity to ___

Answer 87

Narcotics

Question 88

Morphine IV dose ___-___ mg/kg

Answer 88

0.05-0.1 mg/kg

Question 89

Morphine—there is a longer ___ time and ___ in the neonate; elimination half-life in neonates can be up to ___ hours

Answer 89

Longer elimination time and half-life in the neonate; elimination half-life in neonates can be up to 14 hours

Question 90

Fentanyl IV dose—___-___ mcg/kg

Answer 90

1-5 mcg/kg

Question 91

Clearance of fentanyl in neonates is similar to that of older children and adults—T/F?

Answer 91

True

Question 92

Clearance of fentanyl in premature infants is markedly ___; half-life is ___-___ hours

Answer 92

Reduced; half-life is 6-32 hours

Question 93

Remifentanil infusion rate = ___-___ mcg/kg/min

Answer 93

0.02-2 mcg/kg/min

Question 94

Remifentanil onset = ___ minute

Answer 94

1

Question 95

Half-life of remifentanil = ~ ___ minutes

Answer 95

~ 9 minutes

Question 96

Remifentanil is metabolized by ___

Answer 96

Plasma esterases

Question 97

Metabolism of remifentanil is relatively unchanged throughout life; initial studies in children show that clearance, volume of distribution, and half-life of remifentanil are similar to adult values—T/F?

Answer 97

True

Question 98

Bolus IV dose of remifentanil can cause profound ___cardia and possibly ___

Answer 98

Profound bradycardia and possibly asystole

Question 99

Primary purpose of anticholinergic agents in pediatrics is to protect against ___ challenge (prevent ___cardia)

Answer 99

Protect against cholinergic challenge (prevent bradycardia)

Question 100

Neonates are born with a fully developed ___ nervous system

Answer 100

Parasympathetic

Question 101

Sympathetic nervous system does not fully develop until ___-___ months of age

Answer 101

3-6 months of age

Question 102

Another purpose of anticholinergic agents is to inhibit ___

Answer 102

Secretions

Question 103

Anticholinergic agents are also used in combination with anticholinesterase drugs to prevent associated undesirable ___ effects

Answer 103

Muscarinic

Question 104

Atropine IV dose ___-___ mcg/kg; onset ___ minute; duration ___-___ minutes; ___ (does/does not) cross BBB; has more profound ___ effects; is less effective as an anti___

Answer 104

10-20 mcg/kg; onset 1 minute; duration 30-60 minutes; does cross BBB; has more profound cardiac effects; is less effective as an antisialogogue

Question 105

Glycopyrrolate IV dose ___-___ mcg/kg; onset ~___-___ minutes; duration ___-___ minutes; has moderate ___ effects; is better anti___ than atropine

Answer 105

10-20 mcg/kg; onset ~2-3 minutes; duration 30-60 minutes; has moderate cardiac effects; is better antisialogogue than atropine

Question 106

Depolarizing NMB—succs—metabolized by plasma ___; dose infant ___ mg/kg (this is the ED95 dose required to give 95% blockade); may produce profound and sustained ___cardia in the infant and small child; doses are usually preceded by ___

Answer 106

Metabolized by plasma cholinesterase; dose infant 2.2 mg/kg; may produce profound and sustained bradycardia in the infant and small child; doses are usually preceded by atropine

Question 107

Age related differences in succs dose requirements may be related to: cholinesterase activity—___ in infants up to 3 months of age; receptor sensitivity—the ACH receptor ___ with age; volume of distribution—small molecular size and ___ distributed to ECF

Answer 107

Cholinesterase activity—reduced in infants up to 3 months of age; receptor sensitivity—the ACH receptor matures with age; volume of distribution—small molecular size and rapidly distributed to ECF

Question 108

Due to it’s large K+ release, succs is contraindicated in: ___ conditions (i.e.: paraplegia, stroke); ___ dystrophies (Duchenne’s); ___tonia; ___; ___ ___thermia

Answer 108

Neurologic conditions; muscular dystrophies; myotonia; burns; malignant hyperthermia

Question 109

Because of the potential for life threatening side effects, succs use is usually restricted to ___ in the pediatric population (i.e.: ___ induction or ___spasm

Answer 109

Restricted to emergencies (i.e.: RSI or laryngospasm

Question 110

Laryngospasm succs dose ___ mg/kg

Answer 110

0.4 mg/kg

Question 111

Succs can be given ___ or ___ if no PIV is obtained

Answer 111

Sublingual or IM

Question 112

Succs IM dose = ___ mg/kg

Answer 112

4 mg/kg

Question 113

___ muscle relaxants are more commonly used in pediatrics; cardiovascular effects of these drugs are related to the degree of ___ release, ganglionic ___, and ___lysis

Answer 113

Non-depolarizing; degree of histamine release, ganglionic blockade, and vagolysis

Question 114

Rocuronium ___ mg/kg; onset ___ minutes; duration—infants < 10 months = ~ ___ minutes; duration—children 1-5 years = ___ minutes; may be used as an alternative to succinylcholine in ___

Answer 114

0.6 mg/kg; onset 1.5 minutes; duration—infants < 10 months = ~ 45 minutes; duration—children 1-5 years = 26 minutes; may be used as an alternative to succinylcholine in RSI

Question 115

Cisatracurium dose ___-___ mg/kg; onset ___-___ minutes (dose dependent); duration ___-___ minutes; metabolism = ___ elimination

Answer 115

0.1-0.2 mg/kg; onset 2-3 minutes; duration 30-45 minutes; metabolism = Hoffman elimination

Question 116

Pancuronium dose ___ mg/kg; onset ___-___ minutes; duration ___-___ minutes; side effects = ___ effect resulting in ___ (increased/decreased) heart rate

Answer 116

0.1 mg/kg; onset 3-5 minutes; duration 60-100 minutes; side effects = vagolytic effect resulting in increased heart rate

Question 117

Reversal agents—neostigmine and edrophonium—inhibit ___, increasing ___ which competes with the non-depolarizing agent

Answer 117

Inhibit acetylcholinesterase, increasing ACH which competes with the non-depolarizing agent

Question 118

___ (neostigmine or edrophonium) has a stronger bond with true cholinesterase

Answer 118

Neostigmine

Question 119

Neostigmine and edrophonium will work effectively with a high dose of NDNMB on board—T/F?

Answer 119

False—will NOT work effectively…patient must have 2/4 twitches

Question 120

Neostigmine dose ___-___ mcg/kg; atropine ___-___ mcg/kg; glycopyrrolate ___-___ mcg/kg; neostigmine is more ___ as an anticholinesterase than edrophonium but has a ___ onset of action

Answer 120

35-70 mcg/kg; atropine 15-30 mcg/kg; glycopyrrolate 10-20 mcg/kg; neostigmine is more potent as an anticholinesterase than edrophonium but has a slower onset of action

Question 121

Edrophonium dose ___ mg/kg; atropine ___-___ mcg/kg; has more ___ onset of action than neostigmine; must have minimum ___ out of 4 twitches, more appropriately ___ out of ___ twitches with little fade, to be able to use this as a reversal agent

Answer 121

0.5-1.0 mg/kg; atropine 10-20 mcg/kg; has more rapid onset of action than neostigmine; must have minimum 3 out of 4 twitches, more appropriately 4 out of 4 twitches with little fade, to be able to use this as a reversal agent

Question 122

Sugammadex—efficacy and safety has been demonstrated for infants, children, and adolescents as a method for eliminating rocuronium—T/F?

Answer 122

True

Question 123

Sugammadex adult dosing—___ mg/kg for shallow blockade (after appearance of T2); ___ mg/kg for deep blockade (1-2 post-tetanic counts but prior to appearance of T2); ___ mg/kg for rescue dose after administration of intubating dose

Answer 123

2 mg/kg for shallow blockade (3/4 twitches)

4 mg/kg for deep blockade (1/4 or 2/4 twitches)

16 mg/kg for rescue dose after administration of intubating dose

Question 124

Local anesthetics—what (3) are usually used in children?

Answer 124

• Lidocaine
• Bupivacaine
• Ropivacaine

Question 125

Local anesthetics are used for local and intra-___ infiltration, and in ___ blocks

Answer 125

Local and intra-tracheal infiltration, and in caudal blocks

Question 126

Children are more resistant to LA toxicity than adults—T/F?

Answer 126

False! They are NOT more resistant to LA toxicity

Question 127

The first signs of LA toxicity in infants and children may be ___ or ___ collapse

Answer 127

Dysrhythmias or CV collapse

Question 128

Max local doses—lidocaine plain ___ mg/kg; with epi ___ mg/kg

Answer 128

Plain 5 mg/kg; with epi 7 mg/kg

Question 129

Max local doses—bupivacaine plain ___ mg/kg

Answer 129

2.5 mg/kg

Question 130

Max local doses—ropivacaine ___ ml/kg

Answer 130

0.5-1 ml/kg

Question 131

The addition of epi to bupivacaine significantly increases the duration of action—T/F?

Answer 131

False—does NOT significantly increase the duration of action

Question 132

Epi max dose ___-___ mcg/kg/dose, with re-injection of Epi possible after ___ minutes

Answer 132

2-3 mcg/kg/dose, with re-injection of epi possible after 30 minutes

Question 133

Dexmedetomidine is an alpha-___ ___ similar to Clonidine

Answer 133

Alpha-2 agonist

Question 134

Dexmedetomidine has a higher affinity for the ___ receptor

Answer 134

Alpha-2 receptor

Question 135

Dexmedetomidine has ___, ___, and ___lytic effects

Answer 135

Sedative, analgesic, and sympatholytic effects

Question 136

Dexmedetomidine ___ (increases/decreases) IV and inhalation anesthetic requirements

Answer 136

Decreases

Question 137

Dexmedetomidine ___ (increases/decreases) post-operative analgesic requirements

Answer 137

Decreases

Question 138

Dexmedetomidine ___ (does/does not) significantly depress respirations

Answer 138

Does not

Question 139

Dexmedetomidine—initial ___ (increase/decrease) in BP with rapid administration; ___tension and ___cardia occur

Answer 139

Initial increase in BP; hypotension and bradycardia occur

Question 140

Dexmedetomidine dose—bolus ___-___ mcg/kg; infusion ___-___ mcg/kg/hr

Answer 140

Bolus 0.25-1 mcg/kg; infusion 0.2-1 mcg/kg/hr

Question 141

Tranexamic acid (TXA) is an anti___—reversibly blocks the ___ binding site on plasminogen, preventing binding of plasminogen to ___ and conversion to active ___; also improves hemostasis by preventing plasmin-induced ___ activation; anti-___ properties

Answer 141

Antifibrinolytic—reversibly blocks the lysine binding site on plasminogen, preventing the binding of plasminogen to fibrin and conversion to active plasmin; also improves hemostasis by preventing plasmin-induced platelet activation; anti-inflammatory properties

Question 142

TXA is ___ times more potent as an inhibitor of fibrinolysis than aminocaproic acid

Answer 142

10 times

Question 143

TXA loading dose—___ mg/kg; infusion dose—___ mg/kg/hr

Answer 143

Loading dose—30 mg/kg; infusion dose 10 mg/kg/hr