Knowledge Navs Exam 2 Flashcards
(377 cards)
1
Q
Rhabdomyolysis has been reported after succinylcholine in children with ____________
A
Duchenne and Becker muscular dystrophy.
2
Q
The dose response of rocuronium in children with Duchenne muscular dystrophy shows ____________
A
marked prolongation of both the onset and recovery times (two to three times normal).
3
Q
NMBDs in children with severe pre-existing respiratory dysfunction
A
caution
even a small dose of a NMBD may cause profound muscle weakness and the need for ventilatory support.
4
Q
Children with syndromes are relatively sensitive to NMBDs because ____________
A
Most are relatively sensitive to the NMBDs, particularly those with muscular dystrophy, because of muscle wasting.
5
Q
NMBDs in children with burns
A
may require two to three times the usual IV dose of nondepolarizing relaxants.
6
Q
what is the blood volume of a preterm infant
A
90-100 mL/kg
7
Q
blood volume of a term neonae
A
80-90 mL/kg
8
Q
blood volume of infant 3 months to 1 year
A
70-80 mL/kg
9
Q
blood volume of older child
A
70 mL/kg
10
Q
A healthy child readily tolerates a hematocrit well below ____________
A
30%
11
Q
It is our practice not to transfuse otherwise healthy infants up to about 3 months old until their hematocrits have decreased to ____________ and hematocrits of older children have decreased to ____________ if there is little potential for postoperative bleeding.
A
25%; 20%
12
Q
A unit of whole blood can provide …
A
- 1 unit of PRBCs
- 1 unit of whole blood–derived platelets
- 1 unit of fresh frozen plasma (FFP)
13
Q
Succinylcholine-induced muscle fasciculation is associated with (3)
A
- mild hyperkalemia
- increased intragastric and intraocular pressures
- skeletal muscle pains
14
Q
what effects of succinylcholine may occur in patients with neuromuscular disorders?
A
rhabdomyolysis and myoglobinemia
15
Q
The serum potassium concentration increases ____________ after IV succinylcholine in normal children; this increase does not cause arrhythmias
A
1 mEq/L or less
16
Q
Succinylcholine in children with burns
A
Succinylcholine can cause hyperkalemia in children with burns, which may cause a cardiac arrest.
17
Q
smallest burn that has been associated with hyperkalemia
A
8%
18
Q
the first 24 hours after a burn and succinylcholine
A
hyperkalemia after succinylcholine has not been reported in the first 24 hours after a burn
19
Q
Hyperkalemia is thought to result from ____________ along the surface of the muscle membrane in the postburn phase.
A
the upregulation of acetylcholine receptors
20
Q
succinylcholine IV dose for < 1 yr
A
2-3 mg/kg
21
Q
succinylcholine IM dose for > 1 yr
A
4-5 mg/kg
22
Q
For brief cases in which children are anesthetized with 8% inspired sevoflurane, 0.3 mg/kg rocuronium yields satisfactory intubating conditions within ____________
A
2 to 3 minutes.
23
Q
0.3 mg/kg of Rocuronium can be antagonized within approximately ____________ of administration
A
20 minutes
24
Q
PONV relation to age in children
A
PONV is inversely related to age in children
25
PONV ↑ or ↓ throughout childhood
↑
26
The incidence of PONV in children is greatest after what kind of surgeries?
tonsillectomy, strabismus repair, hernia repair, orchiopexy, microtia, and middle ear procedures
27
after puberty who experiences more PONV
girls experience much more than boys
28
The medical complications of PONV include...
pulmonary aspiration, dehydration, electrolyte imbalance, fatigue, wound disruption, and esophageal tears.
29
PONV can produce what kinds of effects in children
psychological effects that may produce anxiety in the children and parents and lead them to avoid further surgery.
30
The most effective prophylaxis strategy in children at moderate or high risk for PONV is to use combination therapy that includes ...
- hydration
- a 5- HT3-receptor antagonist
- a second drug such as dexamethasone
31
A dose of ____________ at the end of surgery effectively reduces emesis after strabismus surgery and tonsillectomy, although the magnitude of its effectiveness may be limited
0.15 mg/kg of metoclopramide
32
metoclopramide mechanism of action
- The antiemetic properties result from its direct effects on the chemoreceptor trigger zone.
- Gastric emptying is a result of the antagonism of the neurotransmitter dopamine, which stimulates gastric smooth muscle activity
33
Some studies report that ____________ is superior to metoclopramide (0.15 mg/kg) for the prophylactic control of postoperative vomiting in children undergoing tonsillectomy.
ondansetron (0.1 mg/kg)
34
Most pediatric anesthesiologists limit their routine of 5-HT3 antagonist use to ...
children undergoing procedures known to have a substantial incidence of PONV, such as:
- strabismus repair
- tonsillectomy
- middle ear surgery
- to children with a known history of motion sickness or previous nausea and vomiting after surgery
*The usual recommended dose is 100 to 150 μg/kg every 6 hours.*
35
The usual recommended dose of ondansetron is ____________
100 to 150 μg/kg every 6 hours
36
A number of studies in children demonstrated that the antiemetic effect of drugs from this class can be improved if they are combined with ____________ or other anesthetic techniques known to reduce vomiting.
dexamethasone
37
Rapid administration of FFP is more likely to be associated with ____________ than the transfusion of components with smaller volumes of plasma (e.g., PRBCs).
citrate toxicity
38
what is initial dose of FFP in peds
10-15 mL/kg
39
T/F FFP contains functional platelets
false, no functional platelets, leukocytes, RBCs
40
midazolam IV dose in peds
0.05-0.15 mg/kg
41
____________ is the only benzodiazepine approved by the FDA for use in neonates, including preterms
midazolam
42
how is midazolam metabolized
hepatic hydroxylation (CYP3A4) ➔ excreted in urine
43
midazolam clearance in neonates
reduced
44
The suggested infusion rate of midazolam is ____________ for preterm infants younger than 32 weeks gestational age
0.5 μg/kg/min
45
The suggested infusion rate of midazolam is ____________ for infants infants greater than 32 weeks gestational age
1 μg/kg/min
46
prolonged admin of midazolam
tolerance, dependency, and benzodiazepine withdrawal
47
Accordingly, one must wait sufficient time between doses of midazolam ____________ to achieve the peak CNS effects before considering supplemental doses or other medications
(3–5 minutes)
48
diazepam dose
0.2-0.3 mg/kg
49
half life of diazepam
20-80 hours
50
metabolism of diazepam
demethylation by CYP 2C19
51
which benzodiazepine is painful when given IV or IM and what can you do to treat it?
diazepam, use lido!
52
diazepam in infants and neonates
Avoided in infants and neonates because of prolonged t ½ and metabolites
53
hypothermia in infants and coagulation
- may worsen major blood loss and replacement
- compromises platelet function & impairs coagulation cascade
54
hypothermia and oxygen consumption
may ↓ O2 consumption and demand ORRRRR increase consumption through shivering
55
hypothermia shift of oxygen-hemoglobin dissociation curve
left shift
56
in the presence of severe hypothermia (about 32°C) what may occur to cardiac rhythm
refractory ventricular tachycardia
57
only allowable method to give warmed blood
Blood warmer device
58
what happens to RBCs if they are overheated > 42º C
RBCs hemolyze
59
Ways to maintain thermal neutrality:
- Warming blood and all other IV infusions with a high-capacity blood warmer
- hot air warming blankets and - radiant warmers
- plastic wrap around extremities
- heated humidifier in the anesthesia circuit
- covering the head
- maintaining a warm to hot operating room
60
what does hypothermia do to most nondepolarizing muscle relaxants
potentiates them and delays elimination
61
How can shivering affect NMB?
Shivering increases oxygen consumption. If respiratory muscles cannot match this → hypoxemia and CO2 retention →acidosis → potentiates NMB.
62
the infant should be warmed if temperature is
< 35º C
63
mild to moderate hypothermia in infants
may cause apnea in infants, alter the pharmacokinetics of medications, decrease blood clotting and increase surgical site infections
64
how does MAC change with temperature
decreases MAC; in children 4 to 10 years, the MAC of isoflurane decreases 5% per degree Celsius
65
most common route of heat loss in infants
radiation (39%)
66
the transfer of energy through the generation of electromagnetic waves to solid surfaces such as cold walls
radiation
67
the transfer of energy from the child by the gas or liquid surrounding it. It can be passive, as in still air, or active when air flows past the infant
convection
68
the loss of heat as liquid is converted to gas. This is typically seen through perspiration but can also occur with major open wounds, and dissipation of cleansing preparation solutions
evaporation
69
the transfer of energy directly from one body to another and can occur in solids, liquids, and gases. Based on their material, objects are conductors (metals) or insulators (gases)
conduction
70
minimum acceptable Hct varies according to ____________
individual need
71
which populations often require a greater hematocrit
severe pulmonary disease or cyanotic congenital heart disease often require a greater hematocrit
72
preterm infant hematocrit requirement is higher bc…
prevent apnea, reduce cardiac and respiratory work, and possibly improve neurologic outcomes
73
healthy infant 3 months old transfusion threshold
Do not transfuse healthy infants up to about 3 months old until their hematocrits have decreased to 25%
74
MABL in Children
75
what medication is directly related to PONV in peds
the morphine dose
>0.1 mg/kg correlates with a 50% or more incidence in vomiting
76
Latino children and morphine
Latino children 4x more pruritus and 7x more vomiting with similar morphine and morphine metabolite values.
77
ondansetron dose in children
100 to 150 µg/kg every 6 hours
78
risks of ondansetron
ventricular tachyarrhthmias (Torsades) if long QT syndrome, esp when using inhalationals (sevoflurane)
79
which agents are better for chemo induced N/V
Granisteron and tropisteron
80
metoclopramide effects
Gastric emptying: dopamine antagonism, which stimulates gastric smooth muscle activity
81
dose of metoclopramide
0.15 mg/kg at the end of strabismus and tonsillectomy surgery
82
Neurokinin 1 Antagonists mechanism of action
- in the brainstem (area postrema and nucleus tractus solitarius)
- receptor for substance P
83
procedures with high risk of PONV
strabismus repair, tonsillectomy, or middle ear surgery
84
upper airway obstruction not included
85
longitudinal stretch during inspiration
laryngospasm
86
Incidence of laryngospasm after maintenance of anesthesia with ____________ is significantly less than with ____________ .
propofol, sevoflurane
87
The effects of spraying the vocal cords with lidocaine on the incidence of laryngospasm and bronchospasm
effects are unclear
88
Prophylactic treatment with glycopyrrolate, ipratropium, or albuterol (does/ does not) affect the incidence of URI-related adverse events.
does not
89
Prophylactic ____________ reduced perioperative airway sequelae in children with URIs.
salbutamol
90
laryngospasm is accompanied by
an inspiratory effort, which longitudinally separates the vocal from the vestibular folds.
91
what is physiologically similar to involuntary laryngeal closure
Glottic closure during forced expiration (forced glottic closure or Valsalva maneuver)
92
hallmark high-pitched inspiratory stridor is caused by
the upper portion of the larynx to be partially open during mild laryngospasm
93
how to relieve laryngospasm
Anterior and upward displacement of the mandible (jaw thrust applied at the condyle of the ascending ramus of the mandible)
94
how does jaw thrust work
Longitudinally separates the base of the tongue, the epiglottis, and the aryepiglottic folds from the vocal cords.
95
predominantly inspiratory stridor suggests
- an upper airway (extrathoracic) lesion: epiglottitis, croup, extrathoracic foreign body
96
both expiratory and inspiratory stridor suggests what kind of lesion
an intrathoracic lesion
- aspirated foreign body, vascular ring or large esophageal foreign body
97
expiratory stridor or prolonged expiratory phase can suggest
lower airway disease
98
RDS can cause (3)
- Reduced lung volumes and lung compliance
- Increased intrapulmonary shunting
- Ventilation-perfusion mismatch
99
clinical manifestations of RDS
- Grunting respirations
- Nasal flaring
- Chest retractions that develop shortly after birth
100
infant normal RR
30-53
101
1-3 y/o normal RR
22-37
102
4-5 y/o normal RR
20-28
103
6-12 y/o normal RR
18-25
104
13-18 y/o normal RR
12-20
105
The upper airway compromises...
the nasal cavities, oral cavity, pharynx, and larynx.
106
The mucosa that lines the upper airway is loose-fitting ____________
pseudostratified columnar epithelium
107
pressure on the mucosa may cause ____________
reactive edema that encroaches on the diameter of the lumen.
108
Because the subglottic region in the infant is smaller in the adult, the same degree of airway edema results in ____________
greater resistance in the infant.
109
Upper airway patency is maintained by
connective tissue and by sustained and cyclic contractions of the pharyngeal dilator muscles.
110
tongue in neonate
large in proportion to the rest of the oral cavity and more easily obstructs the airway, especially in the neonate.
111
larynx in infants
more cephalad at C3-4 (adults C4-5)
112
how many cartilages and bones in larynx
1 bone, 11 cartilages
113
The vocal cords are covered with ____________
stratified epithelium
114
branches of superior laryngeal nerve
- internal branch → sensory innervation to the supraglottic region
- external branch → motor innervation to the cricothyroid muscle
115
recurrent laryngeal nerve function
sensory innervation to the subglottic larynx and motor to all other laryngeal muscles.
116
____________ is the only laryngeal function that alters the cricothyroid angle.
phonation
117
Despite significant airway obstruction during inspiration, it may still be possible to ____________
phonate.
118
____________ is functionally the narrowest portion of the upper airway.
the cricoid cartilage
119
Growth of the subglottic airway occurs rapidly during
the first 2 years of life
120
Cricoid and thyroid cartilages reach adult proportions by ____________
10-12 years of age
121
The____________ is the only complete ring of cartilage in the laryngo tracheobronchial tree - nondistensible.
cricoid
122
how are vocal cords angled
Angled such that the anterior insertion is more caudad than the posterior insertion
123
where might the tip of the ETT be held up
at the anterior commissure of the vocal folds
124
infant epiglottis
shape & angle
narrow, omega shaped, and angled away from the axis of the trachea
125
why is the peds epiglottis shaped like that?
Shape allows the epiglottis to approach the uvula during infant breastfeeding - separating breath from fluid and allowing respiration at the same time as swallowing.
126
upper lip bite
127
focused airway exam
128
defibrillation pads placement for infants < 25 kg
pads placed on chest and back
129
defibrillation pads for kids > 25 kg
pads placed on R. and L. lateral chest
130
joules/kg of pediatric defibrillation
2 joules/kg
131
For V fib/Vtach defibrillation:
2 joules/kg ASYNCHRONOUS;
repeat up to 4 joules/kg
132
For SVT/Vtach cardioversion:
0.5 joules/kg SYNCHRONOUS;
repeat up to 2 joules/kg
133
crystalloid boluses
10-20 ml/kg (up to 3 boluses)
134
colloid bolus amount
20 mL/kg
135
RBC or FFP bolus amount
10-20 mL/kg
136
what is the apnea-hypopnea index (AHI)
Summation of the number of obstructive apnea and hypopnea events
137
obstructive sleep apnea syndrome
periodic cessation of air exchange with apnea episodes lasting longer than 10 sec and AHI indicating the total number of obstructive sleep episodes per hour of sleep is greater than 1
138
AHI 1-5
mild OSA
139
AHI 6-10
moderate OSA
140
AHI > 10
severe OSA
141
what is commonly given as a topical cream for transdermal local anesthetic
lidocaine and prilocaine
142
what might Eutectic Mixture of Local Anesthetics (EMLA) cause
may cause vasoconstriction and blanching, making placement of IV difficult
143
there is a high risk of ____________ with EMLA
methemoglobinemia
144
what is methemoglobinemia
hemoglobin is converted into methemoglobin; decreases available O2 carrying capacity and increases affinity of unaltered hemoglobin for O2, which further impairs O2 delivery
145
neonates have ↑ or ↓ methemoglobin reductase activity compared to older children and adults
reduced activity
146
atropine dose
0.02 mg/kg
younger than 6 months require larger doses to increase heart rate
147
what might atropine and scopolamine cause
decreased ability to sweat ➔ increase in temperature
148
Central sedative effects of both atropine and scopolamine are antagonized with ____________
physostigmine
149
atropine admin in T21 patients
may have narrow-angled glaucoma- caution with administration can worsen
150
scopolamine dose
0.01 mg/kg
151
uses of anticholinergics
diminish secretions preoperatively
**block laryngeal and vagal reflexes**
treat or prevent the bradycardia from succinylcholine,
treat the bradycardia of anesthetic-induced myocardial depression
muscarinic effects of neostigmine
oculocardiac reflex
152
red vs infrared light
red- 660 nm
infrared- 930 nm
153
do SCD and fetal hemoglobin impact pulse oximetry?
no
154
If otherwise safe for the neonate; the oxygen saturation measured by pulse oximetry (SpO2) is between ____________ to minimize the risk of oxygen toxicity without increasing perioperative mortality.
91% and 95%
155
when is a low FiO2 desirable
(1) congenital heart disease to reduce the oxygen saturation to balance the pulmonary and systemic blood flows
(2) airway surgery to reduce the risk of airway fires
(3) in infants and neonates to reduce the risk of retinopathy of prematurity
156
inspiration ____________ venous return to the heart
increases
157
exhalation ____________ venous return to the heart
decreases
158
when is pulsus paradoxus more pronounced?
when there is a decrease in the central venous filling pressure (hypovolemia) or if there is a significant increase in the inspiratory force (upper airway obstruction)
159
____________ is an algorithm used to predict patients whose cardiac output might benefit from fluid bolus
Pleth Variability Index (PVI)
160
when is an uncuffed ETT used
patient less than 8
161
when is cuffed ETT used
patient older than 8
162
uncuffed ETT size
age/4 + 4
163
cuffed ETT size
age/4 + 3 (or 3.5)
164
children with down syndrome require a ____________ ETT
smaller diameter
165
children with cardiac disease often require a ____________ ETT
larger size
166
A sustained inflation pressure of ____________ should be applied to detect an audible or auscultated air leak over the glottis
20 to 25 cm H2O
167
If no leak is detected, the ETT size is ...
excessive and it should be exchanged for one with an ID 0.5 mm smaller
168
distance for ETT insertion
size x 3
169
1000 g ETT size
2.5
170
1000-2500 g ETT size
3.0
171
neonate to 6 month ETT size
3.0 - 3.5
172
6 months - 1 year ETT size
3.5 to 4.0
173
1 to 2 years ETT size
4.0 - 5.0
174
who acts as the decision maker for children and legally can give conset
the parents
175
age group consent vs permission
- <6 years no decision-making capacity - best interest standards
- 6-12 years developing- informed permission informed assent
- 13-18 years mostly developed- informed permissions informed assent
- Mature minors developed- informed consent
- Emancipated minor developed- informed consent
176
recommendations for risk communication to patients
177
If an adolescent has a positive pregnancy test before anesthesia. Given the principles of confidentiality, it is ethically appropriate to inform ____________
only the adolescent.
178
Necessary emergent care for minors who do not have a parent available to give legal consent should be ____________
provided regardless
179
greatest risk age group for preop anxiety
ages 1-5
180
____________ % of children develop fear and anxiety before surgery
40-60%
181
signs of pre-op anxiety
- scared or agitated, breathe deeply, tremble, stop talking or playing, and start to cry.
- some may wet or soil themselves, display increased motor tone, and actively attempt to escape from medical personnel
182
Children who are 6 years or older benefit from ____________ before the surgery
a prep program 5 days
183
prep program had a negative impact for what age group
children less than 3
184
ADVANCE Prep program
185
Children with dynamic obstruction to the left or right ventricular outflow tracts often benefit from sedative premedication because ____________
crying and struggling during induction may worsen obstruction
186
Premedication for infants younger than 6 months of age
is usually unnecessary
187
onset of midazolam
188
the only premedication approved for neonates
Midazolam
189
midazolam provides ____ amnesia
**antero**grade
190
Midazolam can cause respiratory depression and hypotension if given with
fentanyl
191
Midazolam dosing
* 0.1mg/kg IV
* 0.5 -1.0 mg/kg PO Most commonly used
* 0.2 mg/kg nasal
192
T/F:
Versed causes pain on injection in pediatric patients.
False
water soluble
193
Ketamine dosing
(mg/kg)
* oral
* rectal
* nasal
* IM
194
BZD dosing (mg/kg)
195
Clonidine dose
0.004 mg/kg PO
196
You can give morphine IM at what dose
0.1-0.2 mg/kg
197
Give demerol IM at what dose
1-2 mg/kg
198
Fentanyl Oral and nasal dosing
199
Barbiturates dosing (thiopental and methohexital in mg/kg)
200
Basic vs acidic drugs and which plasma protein they bind to
* Basic drugs (lidocaine or alfentanil) bind to plasma a1 acid glycoprotein (AAG)
* Acidic drugs (diazepam, barbiturates) bind to albumin
## Footnote
"Basic girls like the Alpha guys"
201
Neonates have (decreased/increased) protein binding, which means...
decreased
greater unbound drug ready for passive diffusion
202
Neonates have factors that both decrease and increase medication levels bc...
* reduced clearance = increased medication levels
* increased Vd = decreased medication levels
203
kernicterus from medications
* Medications that compete with bilirubin to bind to albumin cause hyperbilirubinemia
* Phenytoin, salicylate, caffeine, ceftriaxone, hypaque
204
Likely to cause methemoglobinemia
EMLA
2.5% lidocaine and 2.5% prilocaine
205
T/F:
Iodine antiseptics likely to cause hyperthyroidism
False
HYPOthyroidism
205
T/F:
Neonates and infants have the same MAC requirements.
False
less in neonates than in infants
206
The difference in the potency (or MAC) of inhalational anesthetics varies inversely with ____
lipid solubility
207
What begins at approximately 0.6 MAC?
decrease in vascular resistance causes a reciprocal increase in CBF
208
The speed of induction dependent on
(4)
* potency/MAC of the agent
* rate of increase of the inspired concentration
* maximum inspired concentration
* respiration
209
Prop
pediatric maintenance infusion rate
200-250 mcg/kg/min
210
An approrpiate way to warn about injection pain from propofol
“warmth” or “sunshine on your arm”
211
Propofol induction dose
3-4 mg/kg
212
Prop
distibution and Cl
Rapid re-distribution, hepatic and extrahepatic clearance (lung, kidney)
213
Prop allergy is due to the
egg white protein
214
T/F:
Prop has less emergence delirium than inhalations and less PONV
True
215
To eliminate pain with propofol injection, pretreat with
* IV lidocaine (0.5 mg/kg),
* meperidine,
* nitrous oxide,
* metoprolol,
* dexmedetomidine,
* low dose ketamine or tramadol
216
PRIS risk, infusion at rates greater than
5 mg/kg per hour
217
The Propofol ED50 for loss of eyelash reflex
* 1–6 months: 3 ± 0.2 mg/kg
* 1–12: 1.3 - 1.6 mg/kg
* 10–16: 2.4 ± 0.1 mg/kg
* ED90-95 LOER for all ages is 50% to 75% > ED50.
* no premedication: propofol (per kg) required for loss of the eyelash reflex is *generally* inversely r/t age
218
Methohexital (brevital)
is a (short/long)-acting barbiturate
short
219
Methohexital (brevital)
IV induction dose
1-2.5 mg/kg
220
T/F:
Expect airway obstruction but not desaturation with Methohexital
False
Oxygen desaturation 4% of cases and can cause airway obstruction (reposition head)
221
Methohexital (brevital)
SEs
Pain on injection
Hiccups
Seizure-like activity
222
T/F
Methohexital can be given rectally as a premedication
True
223
Methohexital Clearance
0.76 L/minute per 70 kg
224
Thiopental
moA
Binds GABAA receptors to prolong chloride channel opening
225
Thiopental CL
0.24 L/minute per 70 kg
(less than Brevital)
226
Thiopental
IV induction dose
3-4 mg/kg
227
Duration of effect depends primarily on redistribution rather than metabolism (10% per hour)
Thiopental
228
Thiopental
effects on myocardium vs vasculature
Myocardial depressant & weak vasodilator (little direct effect on vascular smooth muscle tone)
229
T/F:
Prop causes a greater hypotensive response than thiopental in neonates.
True
The hypotensive response in neonates given thiopental appears not as dramatic as propofol
230
Ketamine
moA
NMDA receptor antagonist
231
Ketamine induction doses
1 - 3 mg/kg IV
5-10 mg/kg IM
232
Ketamine peak concentrations are reached within
10 minutes after 4 mg/kg
IM??
233
Ketamine
desirable effects
Analgesic & amnestic, dissociative amnesia
Bronchodilator
234
Ketamine
UNdesirable effects
* Direct cardiac depressant
* May precipitate seizures in susceptible children
Side effects: nystagmus, increased secretions, 30% increase in intraocular pressure, increased intracranial pressure (cerebral vasodilation) & CMRO2
235
Do adults or peds get higher doses of Ketamine? Why?
Doses are typically larger in children due to greater clearance than in adults
236
Ketamine CV effects and how to lessen them
* increased HR & BP, little effect on pulmonary artery pressure
* fewer cardiovascular effects with the dextro isomer
237
Ketamine Cl
- neonates is reduced (26 L/hour per 70 kg)
- matures to reach adult rates
(80 L/hour per 70 kg; that is, liver blood flow) within the first 6 months of life
238
Why use ketamine IM?
combative larger children
239
Etomidate
moA
Steroid-based hypnotic induction agent
240
Etomidate
is metabolized by
hepatic esterases
241
Etomidate
suppresses adrenal function for up to…
24 hours
242
Etomidate dosing
0.2 - 0.3 mg/kg IV, typically 30% increase in dose in children due to increased volume of distribution
243
T/F:
Etomidate is appropriate for head injuries
True
and CV unstable
244
T/F:
Etomidate has no effect on hemodynamics
True
245
Etomidate side effects
- Emesis
- Adrenal suppression
- Pain on injection
246
Neonates need (less/more) NMB.
less
increased sensitivity
247
Why do neonates need less NMB?
* Neuromuscular transmission is immature until 2 months old
* Reduction in acetylcholine released
* Reduced muscle mass
* Reduced clearance
248
The neonate's diaphragm function may recover earlier than peripheral muscles bc...
Type 1 (slow twitch) diaphragm muscle fibers are most sensitive to NMBDs
BUT
preterm neonate has only ~10% type 1 fibers
249
T/F:
Neonates and infants need lower doses of NMB than adults.
False
Neonates have increased sensitivity
Infants require larger doses than adults
250
Why do infants need higher NMB dose than adults?
Larger volume of distribution due to greater total body water & extracellular fluid
251
T/F:
Neonates have faster NMB onset due to greater cardiac output
True
252
T/F:
Infants are more resistant to Suxx than adults
True
253
How to dose atropine when giving Suxx
10-20 mcg/kg
every 5-10 minutes
254
Suxx has rapid redistribution in
extracellular fluid volume
255
Succinylcholine dose
infants: 3 mg/kg IV or 5 mg/kg IM
children 1.5- 2mg/kg IV or 4 mg/kg IM
## Footnote
Infants more resistant than adults
256
T/F:
You will not see defasiculations from suxx in a toddler
False
1-3 years old can see fasciculations but don’t see them in infant
257
Succinylcholine side effects
* increased masseter muscle tone when given with halothane - masseter spasm potential sign of malignant hyperthermia
* Arrhythmia - bradycardia due to choline metabolites; more likely with 2nd dose
* Hyperkalemia - normal increase K+ ~1 mEq/L; higher in burns, motor neuron lesions & neuromuscular disease
* Increased intraocular pressure
258
How much does Suxx increase K?
What worsens this?
1 mEq/L
higher in burns, motor neuron lesions & neuromuscular disease
259
What is plasma cholinesterase (pseudocholinesterase)
circulating glycoprotein that metabolizes succinylcholine into succinylmonocholine
260
260
Which conditions decrease and increase plasma cholinesterase activity
*Decreases:* severe liver disease, malnutrition, organophosphate poisoning, severe burns, renal failure, plasmapheresis, cyclophosphamide, echothiophate iodide, oral contraceptives
*Increases:* thyroid disease, obesity, nephrotic syndrome, cognitively challenged children
261
Fastest onset of non-depolarizing relaxants
Roc
262
Roc dose may need to be increased if
doing TIVA
263
Which NMB?
Spontaneous degradation not dependent on plasma cholinesterase
Cisatracurium
264
T/F:
Children recovery slower from cisatracurium than adults
False
Faster recovery in children due to greater volume of distribution & total body clearance
265
T/F:
Vecuronium is metabolized by liver and excreted in urine
False
excreted in bile
this is correct for Roc
266
Who is more sensitive to Vec?
infants or children?
infants <1
are more sensitive to vec compared to children
267
T/F:
Vec has no CV effects
True
268
Which NMB is not used in peds?
Pancuronium
Long-acting
> 50% excreted in urine unchanged, 10% in bile
Side effect: tachycardia - blocks presynaptic noradrenaline uptake
269
NMBs by dose
infants and children
270
MAC for neonates
271
What determines Wash In of inhalation agents
272
how does CO affect FA/FI
lower CO = more rapid increase FA/FI
273
T/F:
The slower the FI of nitrous oxide the more rapid the increase FA/FI
False
faster
274
T/F:
Neonates have more bradycardia and hypotension with increasing volatile anesthetics compared to adults
True
Immature sarcoplasmic reticulum in cardiac cells = poor Ca retention and release
275
Premeds can be given for:
(6)
* anxiety,
* block vagal responses/reflexes,
* reduce airway secretions,
* amnesia,
* GI prophylaxis,
* facilitate induction and analgesia
276
Premedicant drugs include:
* Tranquilizers: Versed, diazepam, Lorazepam
* BARBs
* Nonbarbiturate sedatives:
* Chloral hydrate and triclofos
* morphine, fentanyl, sufenta, tramadol, butorphanol, codeine
* Ketamine
* A2 agonists (clonidine, precedex)
* AntiACh
* Topicals (EMLA, ELA Max, S-caine patch
* Tylenol (2+Y)
* corticosteroids
277
major effect of tranquilizers is to allay anxiety but they also have the potential to
produce sedation
278
Tranquilizers
This group of drugs includes:
Benzodiazepines (widely used in children)
Phenothiazines + Butyrophenones (infrequently used)
279
T/F:
Benzodiazepines cause minimal drowsiness and cardiovascular or respiratory depression at low doses.
True
280
most widely used premedication for children
Midaz
281
major advantage of midazolam over other drugs in its class
rapid uptake and elimination
282
Midazolam duration and half life
- short-acting, water-soluble
- elimination half-life of approximately 2 hour
283
Versed routes
IV, IM, nasally, PO, rectally with min irritation
Bitter taste when given PO + nasally
284
Versed dose
Most children are adequately sedated with:
* 0.025 to 0.1 mg/kg IV
* 0.1 to 0.2 mg/kg IM
* 0.25 to 0.75 mg/kg orally
* 0.2 mg/kg nasally
* 0.1 mg/kg rectally
285
T/F:
required dose of midazolam increases as age decreases in children
true
286
CYP 450 Inducers
(↓ DOA Versed)
* anticonvulsants (phenytoin and carbamazepine)
* rifampin
* St. John's wort
* glucocorticoids
* barbiturates
287
T/F:
PO Versed is effective in sedation but increases residual volume
False
effective and does NOT increase gastric pH or residual volume
288
CYP 450 Inhibitors
(prolonged sedation w/ Versed)
* grapefruit juice
* erythromycin
* protease inhibitors
* calcium-channel blockers
289
Increased postoperative sedation may be attributed to synergism between
propofol and midazolam on GABA receptors
290
children can become agitated after giving midazolam by which route?
wyd?
oral
IV Ketamine (0.5 mg/kg) may reverse the agitation
291
Nasal versed
- onset
- effectiveness
- onset: anxiolysis + sedation within 10 mins
- not well accepted because it causes irritation, discomfort + burning aftertaste
292
T/F:
IV Versed can cause neurotixicity.
False
Nasal
Potential to cause neurotoxicity via the cribriform plate (use preservative free only)
293
Diazepam should only be used for premedication of older children bc...
infants + premies immature hepatic function causes markedly prolonged elimination half life
294
Diazepam
Active metabolite:
- desmethyldiazepam
- pharmacologic activity equal to diazepam with half life > 9 days
295
Most effective routes for diazepam
IV
(followed by PO then rectal)
296
T/F:
Like Versed, Diazepam can be given IM.
False
do not give Diazepam IM
pain + erratic absorption
297
Lorazepam
dose
(0.05 mg/kg): PO, IV, or IM
298
These BZDs are reserved primarily for older children
Diazepam
Lorazepam
299
Why use Lorazepam instead of Diazepam?
Causes less tissue irritation + more reliable amnesia than diazepam
Inactive metabolites
300
IV form of this BZD is avoided in neonates because it may be neurotoxic
Lorazepam
301
Diazepam vs Lorazepam
onset
doA
Lorazepam is slower and longer
302
advantages of barbiturates
minimal respiratory or cardiovascular depression, anticonvulsant effects, and a very low incidence of nausea and vomiting
303
relatively short-acting barbiturates thiopental and methohexital may be given rectally as a
10% solution
304
T/F:
Barbiturates are infrequently used for premedication
True
305
How to give rectal thiopental or methohexital
30 mg/kg via a shortened suction catheter, which produces sleep in about two-thirds of the children within 15 minutes
## Footnote
10% solution
306
What to monitor for when giving rectal thiopental or methohexital
sedation may be profound, resulting in airway obstruction and laryngospasm
always have: source of oxygen, suction, and a means for providing ventilatory support
307
disadvantages of rectal methohexital
- unpredictable systemic absorption
- defecation
- hiccups
308
Children chronically treated with _____ are more resistant to the effects of rectally administered methohexital
phenobarbital or phenytoin
309
Contraindications to methohexital
- hypersensitivity
- temporal lobe epilepsy
- latent or overt porphyria
**do NOT give rectal if rectal mucosal tears or hemorrhoids**
310
Nonbarbiturate sedatives
- Chloral hydrate and triclofos
- orally administered nonbarbiturate drugs used to sedate children
- both are slow onset and relatively long acting
311
Chloral hydrate
is rarely used bc...
- unreliable
- has a prolonged DOA
- unpleasant taste
- irritating to skin mucosa & GI tract
312
Chloral hydrate use in ____ is not recommended because of impaired metabolism
neonates
313
Opioids:
SEs
N/V, respiratory depression, sedation, + dysphoria
314
All children that receive opioid premedication should be...
continuously observed + monitored with pulse ox
315
Morphine IV dose
0.05 to 0.1 mg/kg
316
Other than IV, what routes can we give Morphine?
Pros and cons
IM
Also effective when given PO
rectally not recommended because erratic absorption
317
____ are more sensitive to the respiratory depressant effects of morphine (rarely used)
Neonates
318
Fentanyl:
was introduced in a “lollipop” delivery system known as
oral transmucosal fentanyl citrate (OTFC)
no longer used for this
319
T/F:
Fentanyl has a moderate incidence of PONV
False
HIGH
319
Which opioid is Currently used to treat breakthrough cancer pain
Fentanyl
320
How to utilize Fentanyl
administered nasally (1 to 2 µg/kg)
primarily after induction to provide analgesia in children without IV access
321
Sufentanil is ___ times more potent than fentanyl
10
322
Sufenta
administered nasally in a dose of
1.5 to 3 µg/kg
323
Sufenta isnt a popular choice for premedication bc....
the adverse effects
more PONV and reduced chest wall compliance and prolonged hospital stay
324
After giving this drug for premideication, children are usually calm and cooperative, and most separate from their parents with minimal distress
Sufenta
325
Tramadol
moA
weak µ-opioid receptor agonist
analgesic effect is mediated via inhibition of norepinephrine reuptake and stimulation of serotonin release
326
How does Tramadol affect breathing and bleeding?
devoid of action on platelets and does not depress respirations in the clinical dose range
327
Tramadol
peak
doA
metab
* Serum concentrations peak by 2 hours after oral dosing
* analgesia for 6 to 9 hours.
* metabolized by CYP2D6
328
Butorphanol
moA
synthetic opioid agonist-antagonist with properties similar to those of morphine that can be administered nasally
329
Butorphanol:
most frequent adverse effect
sedation that resolves approximately 1 hour after administration
330
Tramadol
how much and when to give
dose of 0.025 mg/kg administered nasally immediately after the induction
331
Opioids + Midazolam
more respiratory depression than opioids or midazolam alone
decrease dose of both
332
Codeine is a prodrug that must undergo _____ in the liver to produce morphine to provide effective analgesia
O-demethylation
333
oral codeine dose
0.5 to 1.5 mg/kg
334
Codeine
onset
duration
* onset within 20 minutes
* peak effect between 1 and 2 hours
* elimination half-life 2.5 to 3 hours.
335
combination of codeine with acetaminophen is effective in relieving
mild to moderate pain
336
Some children do not get analgesia from codeine. Why?
5% and 10% of children lack the cytochrome isoenzyme (CYP2D6) required for conversion
337
A normal codeine dose in these children can be an overdose
obstructive sleep apnea
altered mu receptors and increased analgesia
338
Ketamine
moA
Dissociates cortex from limbic system, producing sedation and analgesia
but preserves airway reflexes and respiratory drive
bronchodilation
339
Ketamine uses
pre-med, opioid-sparing adjunct, in asthmatics
340
Ketamine preserves airway reflexes and respiratory drive but what are the cons?
* hallucinations, nightmares,
* nystagmus,
* sialorrhea,
* increased PONV
* high doses IM = more psychological effects
341
You're giving Versed to mitigate the negative psych effects on Ketamine. What should you consider?
versed mitigates this but prolongs recovery from anesthesia
342
“Ketamine Dart”
high concentration Ketamine,
+/- versed,
+/- antisialagogue
343
Ketamine with the addition of _____ is recommended to decrease sialorrhea
atropine or glycopyrrolate
344
IM ketamine is an effective means of sedating which pts?
combative, apprehensive, or developmentally delayed children who are otherwise uncooperative and refuse oral medication
345
Ketamine IM dose
IM: 2-5mg/kg, EA 3-5min
* 2mg/kg, +/- 0.1-0.2mg/kg versed, for mask induction
* 4-5mg/kg for induction dose if BP stability needed (CHD)
* Up to 10mg/kg for up to 25 min need- most SE (good for burn pts)
346
Ketamine PO dose
PO: 5-6mg/kg, EA 12 min
3mg/kg + 0.5mg/kg versed works better and did not prolong recovery in cases longer than 30min
347
T/F:
Oral ketamine alone or in combination with oral midazolam is an effective premedication to alleviate the distress of invasive procedures
True
348
Nasal ketamine dose, usage, onset
6 mg/kg
effective premedication
sedation developing by 20 to 40 minutes
349
Rectal ketamine dose, absorption, & uses
* 5 mg/kg
* good anxiolysis and sedation within 30 minutes
* but unreliable absorption
350
Clonidine
moA
α2-agonist
dose-related sedation by its effect in the locus coeruleus
351
T/F:
Clonidine attenuates the hemodynamic response to intubation
True
acts both centrally and peripherally to reduce blood pressure
352
T/F:
Clonidine is devoid of respiratory depressant properties, even when administered in an overdose
True
353
T/F:
Clonidine decreases MAC requirements but may prolong emergence.
False
does not prolong emergence
354
T/F:
Oral clonidine 4 µg/kg reduces the incidence of vomiting after strabismus surgery
True!
355
Oral clonidine offers sedation and analgesia but must be given _____ before induction
60 mins
impractical in busy outpatient setting
356
Dexmedetomidine
moA
## Footnote
(not as common as clonidine)
* Great affinity for alpha-2 receptors
* produces sedation
* reduces postop opioid requirements
* useful as opioid sparing adjunct
* improves separation anxiety
357
T/F:
In contrast to clonidine, Precedex in higher doses can prolong emergence and recovery
True!
esp in combination with other sedating drugs
358
Precedex
Beware of _____ with rapid dosing
bradycardia
359
Precedex dosing
* PO: 2-4mcg/kg, effective in 20-30min
* IN: 2-3mcg/kg, effective in 30-45min
* IV: up to 1-1.5mcg/kg over 10min, effective in ~15min
360
Anticholinergics:
Uses
* prevent bradycardia from agents (sux, halothane)
* Block vagal reflexes from surgical stimulation (laryngoscopy, insufflation, strabismus repair)
* Decrease secretions
361
AntiACh SEs
tachycardia, dry mouth, impaired sweating
Scopolamine and atropine cross BBB- may cause agitation, confusion, restlessness, memory loss
362
AntiACh
Safety in pediatrics
with neonates, have atropine ready
kids are HR dependent
0.01-0.02mg/kg
Glyco- consider thoughtfully d/t uncomfortable s/e of dry mouth
0.01mg/kg
363
Atropine vs Glyco strength
Glyco is twice as potent at blocking secretions and lasts 3x longer
careful consideration when giving glyco
364
Topical Anesthetics:
EMLA
Lidocaine & Prilocaine
Occlusive dressing for one hour
Can cause vasoconstriction and blanching- increased difficult IV
365
ELA-Max
4% lido
Requires only 30min
Less vasoconstriction than EMLA
366
S-caine patch
lido and tetracaine
Heat controlled patch for accelerated delivery- only 20min
Theoretically should dilate
367
Acetaminophen
FDA approved for children....
2 years and older
368
Tylenol dosing
* PO: 10-15mg/kg
IV:
*2-12yrs: 15mg/kg q6hrs
* 1month- 2yrs: 12.5mg/kg q6hr or 10mg/kg q4h (max 50-60mg/kg/day)
* FT neonates up to 28days: 7.5mg/kg q6hr (max 30mg/kg/day
369
Who should get Corticosteroids as premedication?
currently taking or who have discontinued chronic corticosteroid treatment in the last 6 mons
370
Corticosteroids
usual recommended dose
hydrocortisone IM or IV: 1-2 mg/kg
or
equivalent of dexamethasone (0.05 to 0.1 mg/kg)
1 hour before induction or as soon as IV access is established
371
How long do we wait between corticosteroid doses?
dose may be repeated every 6 hours for up to 72 hours
372
GI drugs
dosing chart
373
Only a single dose of ____ is recommended due to metabolites that can cause seizures
meperidine
374
TABLE 4.4
Surgical Antibiotic Prophylaxis (Weight-Normalized)
